{"id":591,"date":"2015-12-11T10:42:17","date_gmt":"2015-12-11T19:42:17","guid":{"rendered":"\/blog\/?p=591"},"modified":"2023-09-21T09:38:07","modified_gmt":"2023-09-21T00:38:07","slug":"ardupilot-changelog","status":"publish","type":"post","link":"https:\/\/hasu0707.duckdns.org\/blog\/?p=591","title":{"rendered":"Ardupilot ChangeLog"},"content":{"rendered":"\n
APM:Copter Release Notes:<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3.2 01-Dec-2015 \/ 3.3.2-rc2 18-Nov-2015<\/span><\/font><\/div>
Changes from 3.3.2-rc1<\/span><\/font><\/div>
1) Bug fix for desired climb rate initialisation that could lead to drop when entering AltHold, Loiter, PosHold<\/span><\/font><\/div>
2) Fix to hard landings when WPNAV_SPEED_DN set high in RTL, Auto (resolved by using non-feedforward alt hold)<\/span><\/font><\/div>
3) Reduce Bad AHRS by filtering innovations<\/span><\/font><\/div>
4) Allow arming without GPS if using Optical Flow<\/span><\/font><\/div>
5) Smoother throttle output in Guided mode's velocity control (z-axis now 400hz)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3.2-rc1 4-Nov-2015<\/span><\/font><\/div>
Changes from 3.3.1<\/span><\/font><\/div>
1) Helicopter Improvements:<\/span><\/font><\/div>
    a) Fix Arming race condition<\/span><\/font><\/div>
    b) Fix servos to move after arming in Stabilize and Acro<\/span><\/font><\/div>
    c) Implement Pirouette Compensation<\/span><\/font><\/div>
    d) Add Rate I-Leak-Min functionality<\/span><\/font><\/div>
    e) Add new Stab Collective and Acro Expo Col functions<\/span><\/font><\/div>
    f) Add circular swashplate limits (Cyclic Ring)<\/span><\/font><\/div>
    g) Add new H_SV_Man functions<\/span><\/font><\/div>
    h) Add Hover Roll Trim function<\/span><\/font><\/div>
    i) Add Engine Run Enable Aux Channel function<\/span><\/font><\/div>
    j) Add servo boot test function<\/span><\/font><\/div>
    h) Add Disarm Delay parameter<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3.1 26-Oct-2015 \/ 3.3.1-rc1 20-Oct-2015<\/span><\/font><\/div>
Changes from 3.3<\/span><\/font><\/div>
1) Bug fix to prevent potential crash if Follow-Me is used after an aborted takeoff<\/span><\/font><\/div>
2) compiler upgraded to 4.9.3 (runs slightly faster than 4.7.2 which was used previously)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3 29-Sep-2015 \/ 3.3-rc12 22-Sep-2015<\/span><\/font><\/div>
Changes from 3.3-rc11<\/span><\/font><\/div>
1) EKF recovers from pre-arm \"Compass variance\" failure if compasses are consistent<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc11 10-Sep-2015<\/span><\/font><\/div>
Changes from 3.3-rc10<\/span><\/font><\/div>
1) PreArm \"Need 3D Fix\" message replaced with detailed reason from EKF<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc10 28-Aug-2015<\/span><\/font><\/div>
Changes from 3.3-rc9<\/span><\/font><\/div>
1) EKF improvements:<\/span><\/font><\/div>
    a) simpler optical flow takeoff check<\/span><\/font><\/div>
2) Bug Fixes\/Minor enhancements:<\/span><\/font><\/div>
    a) fix INS3_USE parameter eeprom location<\/span><\/font><\/div>
    b) fix SToRM32 serial protocol driver to work with recent versions<\/span><\/font><\/div>
    c) increase motor pwm->thrust conversion (aka MOT_THST_EXPO) to 0.65 (was 0.50)<\/span><\/font><\/div>
    d) Firmware version sent to GCS in AUTOPILOT_VERSION message<\/span><\/font><\/div>
3) Safety:<\/span><\/font><\/div>
    a) pre-arm check of compass variance if arming in Loiter, PosHold, Guided<\/span><\/font><\/div>
    b) always check GPS before arming in Loiter (previously could be disabled if ARMING_CHECK=0)<\/span><\/font><\/div>
    c) sanity check locations received from GCS for follow-me, do-set-home, do-set-ROI<\/span><\/font><\/div>
    d) fix optical flow failsafe (was not always triggering LAND when optical flow failed)<\/span><\/font><\/div>
    e) failsafe RTL vs LAND decision based on hardcoded 5m from home check (previously used WPNAV_RADIUS parameter)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc9 19-Aug-2015<\/span><\/font><\/div>
Changes from 3.3-rc8<\/span><\/font><\/div>
1) EKF improvements:<\/span><\/font><\/div>
    a) IMU weighting based on vibration levels (previously used accel clipping)<\/span><\/font><\/div>
    b) fix blended acceleration (used for altitude control) in cases where first IMU fails<\/span><\/font><\/div>
    c) ensure unhealthy barometer values are never consumed<\/span><\/font><\/div>
2) TradHeli: remove acceleration feed forward<\/span><\/font><\/div>
3) Safety:<\/span><\/font><\/div>
    a) check accel, gyro and baro are healthy when arming (previously was only checked pre-arm)<\/span><\/font><\/div>
    b) Guided mode velocity controller timeout (vehicle stops) after 3 seconds with no update from GCS<\/span><\/font><\/div>
4) Minor enhancements:<\/span><\/font><\/div>
    a) fix for AUAV board's usb-connected detection<\/span><\/font><\/div>
    b) add Lidar-Lite-V2 support<\/span><\/font><\/div>
    c) MOT_THR_MIN_MAX param added to control prioritisation of throttle vs attitude during dynamic flight<\/span><\/font><\/div>
    d) RALLY_INCL_HOME param allows always including home when using rally points<\/span><\/font><\/div>
    e) DO_FLIGHT_TERMINATION message from GCS acts as kill switch<\/span><\/font><\/div>
5) Bug Fixes:<\/span><\/font><\/div>
    a) fix to ensure motors start slowly on 2nd spin-up<\/span><\/font><\/div>
    b) fix RTL_CLIMB_MIN feature (vehicle climbed too high above home)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc8 25-Jul-2015<\/span><\/font><\/div>
Changes from 3.3-rc7<\/span><\/font><\/div>
1) EKF improvements:<\/span><\/font><\/div>
    a) de-weight accelerometers that are clipping to improve resistance to high vibration<\/span><\/font><\/div>
    b) fix EKF to use primary compass instead of first compass (normally the same)<\/span><\/font><\/div>
2) UBlox \"HDOP\" corrected to actually be hdop (was pdop) which leads to 40% lower value reported<\/span><\/font><\/div>
3) TradHeli:<\/span><\/font><\/div>
    a) Motors library split into \"Multicopter\" and \"TradHeli\" so TradHeli does not see multicopter parameters<\/span><\/font><\/div>
    b) Heading target reset during landing to reduce vehicle fighting to rotate while on the ground<\/span><\/font><\/div>
4) Minor enhancements:<\/span><\/font><\/div>
    a) SToRM32 gimbal can be connected to any serial port<\/span><\/font><\/div>
    b) log when baro, compass become unhealthy<\/span><\/font><\/div>
    c) ESC_CALIBRATION parameter can be set to \"9\" to disable esc calibration startup check<\/span><\/font><\/div>
    d) Circle rate adjustment with ch6 takes effect immediately<\/span><\/font><\/div>
    e) log home and origin<\/span><\/font><\/div>
    f) pre-arm check of battery voltage and fence<\/span><\/font><\/div>
    g) RTL_CLIMB_MIN parameter forces vehicle to climb at least this many cm when RTL is engaged (default is zero)<\/span><\/font><\/div>
5) Bug fixes:<\/span><\/font><\/div>
    a) fix THR_MIN being incorrectly scaled as pwm value during low-throttle check<\/span><\/font><\/div>
    b) fence distance calculated from home (was incorrectly calculated from ekf-origin)<\/span><\/font><\/div>
    c) When flying with joystick and joystick is disconnected, control returns immediately to regular TX<\/span><\/font><\/div>
    d) dataflash's ATT yaw fixed to report heading as 0 ~ 360<\/span><\/font><\/div>
    e) fix to mission's first command being run multiple times during mission if it was a do-command<\/span><\/font><\/div>
    f) ekf-check is enabled only after ekf-origin is set (stops red-yellow flashing led when flying without GPS lock)<\/span><\/font><\/div>
    g) fix initialisation of mount's mode<\/span><\/font><\/div>
    h) start-up logging so parameters only logged once, mission always written<\/span><\/font><\/div>
6) Linux:<\/span><\/font><\/div>
    a) bebop support<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc7 28-Jun-2015<\/span><\/font><\/div>
Changes from 3.3-rc6<\/span><\/font><\/div>
1) reduce EKF gyro bias uncertainty that caused attitude estimate errors<\/span><\/font><\/div>
2) force 400hz IMU logging on (temporary for release candidate testing)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc6 25-Jun-2015<\/span><\/font><\/div>
Changes from 3.3-rc5<\/span><\/font><\/div>
1) EKF related changes:<\/span><\/font><\/div>
    a) reset altitude even when arming without GPS lock<\/span><\/font><\/div>
    b) fix yaw twitch caused by EKF heading estimate reset<\/span><\/font><\/div>
    c) fix IMU time scaling bug that caused height estimate to deviate from the baro<\/span><\/font><\/div>
2) AutoTune improvements:<\/span><\/font><\/div>
    a) improved yaw tuning by increasing yaw step magnitude<\/span><\/font><\/div>
    b) added logging of accelerations<\/span><\/font><\/div>
    c) improvements to step tests<\/span><\/font><\/div>
3) Improved crash check:<\/span><\/font><\/div>
    a) allow triggering even if pilot doesn't move throttle to zero<\/span><\/font><\/div>
    b) easier triggering by removing baro check and using angle error instead of absolute tilt angle<\/span><\/font><\/div>
4) TradHeli:<\/span><\/font><\/div>
    a) swash moves while landed in AltHold mode<\/span><\/font><\/div>
    b) improvements to land detector<\/span><\/font><\/div>
    c) fixed RSC Runup Time calculation<\/span><\/font><\/div>
    d) Rate FF Low-pass Filter changed from 5Hz to 10Hz, more responsive<\/span><\/font><\/div>
5) support Linux builds for NAVIO+ and Erle-Brain (http:\/\/firmware.diydrones.com\/Copter\/beta\/)<\/span><\/font><\/div>
6) Other improvements \/ Bug Fixes:<\/span><\/font><\/div>
    a) sonar pre-arm checks only enforced if using optical flow<\/span><\/font><\/div>
    b) fix EKF failsafe bug that would not allow recovery<\/span><\/font><\/div>
    c) full rate IMU logging for improved vibration analysis (set LOG_BITMASK to All+FullIMU)<\/span><\/font><\/div>
    d) new VIBE dataflash message records vibration levels<\/span><\/font><\/div>
    e) default MNT_TYPE to \"1\" if servo gimbal rc outputs were defined<\/span><\/font><\/div>
    f) RC_FEEL defaults to medium<\/span><\/font><\/div>
    g) addition of SToRM32 serial support (supports mount angle feedback to GCS)<\/span><\/font><\/div>
    h) new tricopter's tail servo parameters (MOT_YAW_SV_MIN, MAX, TRIM, REV)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc5 23-May-2015<\/span><\/font><\/div>
Changes from 3.3-rc4<\/span><\/font><\/div>
1) Fix AHRS bad gyro health message caused by timing jitter and log IMU health<\/span><\/font><\/div>
2) TradHeli:<\/span><\/font><\/div>
    a) better default rate PIDs<\/span><\/font><\/div>
    b) Collective pitch output now operates even when disarmed<\/span><\/font><\/div>
3) Small changes\/fixes:<\/span><\/font><\/div>
    a) GCS can use MAV_CMD_MISSION_START to start mission in AUTO even without pilot raising throttle<\/span><\/font><\/div>
    b) GCS can force disarming even in flight by setting param2 to \"21196\"<\/span><\/font><\/div>
    c) rc-override timeout reduced from 2 seconds to 1 (applies when using GCS joysticks to control vehicle)<\/span><\/font><\/div>
    d) do-set-speed fix so it takes effect immediately during missions<\/span><\/font><\/div>
    e) GCS failsafe disarms vehicle if already landed (previously it could RTL)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc4 17-May-2015<\/span><\/font><\/div>
Changes from 3.3-rc3<\/span><\/font><\/div>
1) AutoTune:<\/span><\/font><\/div>
    a) save roll, pitch, yaw rate acceleration limits along with gains<\/span><\/font><\/div>
    b) more conservative gains<\/span><\/font><\/div>
2) Roll, pitch rate control feed-forward now on by default (set ATC_RATE_FF_ENAB to \"0\" to disable)<\/span><\/font><\/div>
3) Serial ports increased to maximum of 4 (set SERIALX_PROTOCOL to 1)<\/span><\/font><\/div>
4) MOT_THR_MIX_MIN param to control minimum throttle vs attitude during landing (higher = more attitude control but bumpier landing)<\/span><\/font><\/div>
5) EKF fixes\/improvements<\/span><\/font><\/div>
    a) prevent yaw errors during fast spins<\/span><\/font><\/div>
    b) bug fix preventing external selection of optical flow mode<\/span><\/font><\/div>
6) Parachute:<\/span><\/font><\/div>
    a) servo\/relay held open for 2sec when deploying (was 1sec)<\/span><\/font><\/div>
    b) fix altitude check to be alt-above-home (was alt-above ekf origin which could be slightly different)<\/span><\/font><\/div>
7) TradHeli:<\/span><\/font><\/div>
    a) parameters moved to stop possibility of corruption if board is switched between tradheli and multicopter firmware.  Heli users may need to re-setup some heli-specific params.<\/span><\/font><\/div>
    b) H_COLYAW param can be float<\/span><\/font><\/div>
8) Small Improvements \/ Bug Fixes:<\/span><\/font><\/div>
    a) reduced spline overshoot after very long track followed by very short track<\/span><\/font><\/div>
    b) log entire mission to dataflash whenver it's uploaded<\/span><\/font><\/div>
    c) altitude reported if vehicle takes off before GPS lock<\/span><\/font><\/div>
    d) high speed logging of IMU<\/span><\/font><\/div>
    e) STOP flight mode renamed to BRAKE and aux switch option added<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc2\/rc3 02-May-2015<\/span><\/font><\/div>
Changes from 3.3-rc1<\/span><\/font><\/div>
1) AutoTune reliability fixes (improved filtering to reduce noise interference)<\/span><\/font><\/div>
2) Optical flow improvements:<\/span><\/font><\/div>
    a) Range Finder pre-arm check - lift vehicle between 50cm ~ 2m before arming.  Can be disabled by setting ARMING_CHECK to \"Skip Params\/Sonar\"<\/span><\/font><\/div>
    b) Vehicle altitude limited to range finder altitude when optical flow is enabled<\/span><\/font><\/div>
3) AltHold & Take-off changes:<\/span><\/font><\/div>
    a) feed-forward controller and jerk limiting should result in slightly snappier performance and smoother take-offs<\/span><\/font><\/div>
    b) vehicle climbs automatically to PILOT_TKOFF_ALT alt when taking off in Loiter, AltHold, PosHold, Sport (disabled by default, pilot's throttle input overrides takeoff)<\/span><\/font><\/div>
    c) PILOT_THR_FILT allows enforcing smoother throttle response in manual flight modes (defaults to 0 = off)<\/span><\/font><\/div>
    d) TX with sprung throttle can set PILOT_THR_BHV to \"1\" so motor feedback when landed starts from mid-stick instead of bottom of stick<\/span><\/font><\/div>
    e) GCS can initiate takeoff even in Loiter, AltHold, PosHold and sport by issuing NAV_TAKEOFF mavlink command<\/span><\/font><\/div>
4) Stop flight mode - causes vehicle to stop quickly, and does not respond to user input or waypoint movement via MAVLink.  Requires GPS, will be renamed to Brake mode.<\/span><\/font><\/div>
5) Aux channel features:<\/span><\/font><\/div>
    a) Emergency Stop - stops all motors immediately and disarms in 5 seconds<\/span><\/font><\/div>
    b) Motor Interlock - opposite of Emergency Stop, must be on to allow motors to spin motors, must be off to arm<\/span><\/font><\/div>
6) Air pressure gain scaling (of roll, pitch, yaw) should mostly remove need to re-tune when flying at very different altitudes<\/span><\/font><\/div>
7) landing detector simplified to only check vehicle is not accelerating & motors have hit their lower limit<\/span><\/font><\/div>
8) Loiter tuning params to remove \"freight train\" stops:<\/span><\/font><\/div>
       raising WPNAV_LOIT_MAXA makes vehicle start and stop faster<\/span><\/font><\/div>
       raising WPNAV_LOIT_MINA makes vehicle stop more quickly when sticks centered<\/span><\/font><\/div>
9) Other items:<\/span><\/font><\/div>
    a) faster EKF startup<\/span><\/font><\/div>
    b) Camera control messages sent via MAVLink to smart cameras.  Allow control of camera zoom for upcoming IntelEdison\/Sony QX1 camera control board<\/span><\/font><\/div>
    c) Lost Copter Alarm can be triggered by holding throttle down, roll right, pitch back<\/span><\/font><\/div>
10) Bug fixes:<\/span><\/font><\/div>
    a) Home position set to latest arm position (it was being set to previous disarm location or first GPS lock position)<\/span><\/font><\/div>
    b) bug fix to mission Jump to command zero<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
Copter 3.3-rc1 11-Apr-2015<\/span><\/font><\/div>
Changes from 3.2.1<\/span><\/font><\/div>
1) Only support fast CPUs boards (Pixhawk, VRBrain, etc) and drop support for APM1, APM2 (sorry!)<\/span><\/font><\/div>
2) AutoTune for yaw<\/span><\/font><\/div>
3) Smooth throttle curve which should reduce wobbles during fast climbs and descents<\/span><\/font><\/div>
4) ch7\/ch8 aux switches expanded to ch9 ~ ch12 (see CH9_OPT ~ CH12_OPT params)<\/span><\/font><\/div>
5) PX4Flow support in Loiter mode (still somewhat experimental)<\/span><\/font><\/div>
6) Safety features:<\/span><\/font><\/div>
    a) EKF on by default replacing DCM\/InertialNav which should improve robustness<\/span><\/font><\/div>
    b) increased accelerometer range from 8G to 16G to reduce chance of climb due to high vibrations (requires accel calibration)<\/span><\/font><\/div>
7) Landing features:<\/span><\/font><\/div>
    a) improved landing on slopes<\/span><\/font><\/div>
    b) retractable landing gear (see LGR_ parameters)<\/span><\/font><\/div>
8) Camera Gimbal features:<\/span><\/font><\/div>
    a) SToRM32 gimbal support (using MAVLink)<\/span><\/font><\/div>
    b) AlexMos gimbal support (using AlexMos serial interface)<\/span><\/font><\/div>
    c) do-mount-control commands supported in missions (allows controlling gimbal angle in missions)<\/span><\/font><\/div>
9) Battery related features:<\/span><\/font><\/div>
    a) PID scaling for battery voltage (disabled by default, see MOT_THST_BAT_ parameters)<\/span><\/font><\/div>
    b) smart battery support<\/span><\/font><\/div>
10) Other:<\/span><\/font><\/div>
    a) support do-set-home command (allows return-to-me and locked home position once GCS enhancements are completed)<\/span><\/font><\/div>
    b) performance improvements for Pixhawk reduce CPU load from 80% to 15%<\/span><\/font><\/div>
    c) firmware string name changed from ArduCopter to APM:Copter<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2.1 11-Feb-2015 \/ 3.2.1-rc2 30-Jan-2015<\/span><\/font><\/div>
Changes from 3.2.1-rc1<\/span><\/font><\/div>
1) Bug Fixes:<\/span><\/font><\/div>
    a) prevent infinite loop with linked jump commands<\/span><\/font><\/div>
    b) Pixhawk memory corruption fix when connecting via USB<\/span><\/font><\/div>
    c) vehicle stops at fence altitude limit in Loiter, AltHold, PosHold<\/span><\/font><\/div>
    d) protect against multiple arming messages from GCS causing silent gyro calibration failure<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2.1-rc1 08-Jan-2015<\/span><\/font><\/div>
Changes from 3.2<\/span><\/font><\/div>
1) Enhancements:<\/span><\/font><\/div>
    a) reduced twitch when passing Spline waypoints<\/span><\/font><\/div>
    b) Faster disarm after landing in Auto, Land, RTL<\/span><\/font><\/div>
    c) Pixhawk LED turns green before arming only after GPS HDOP falls below 2.3 (only in flight modes requiring GPS)<\/span><\/font><\/div>
2) Safety Features:<\/span><\/font><\/div>
    a) Add desired descent rate check to reduce chance of false-positive on landing check<\/span><\/font><\/div>
    b) improved MPU6k health monitoring and re-configuration in case of in-flight failure<\/span><\/font><\/div>
    c) Rally point distance check reduced to 300m (reduces chance of RTL to far away forgotten Rally point)<\/span><\/font><\/div>
    d) auto-disarm if vehicle is landed for 15seconds even in Auto, Guided, RTL, Circle<\/span><\/font><\/div>
    e) fence breach while vehicle is landed causes vehicle to disarm (previously did RTL)<\/span><\/font><\/div>
3) Bug Fixes:<\/span><\/font><\/div>
    a) Check flight mode even when arming from GCS (previously it was possible to arm in RTL mode if arming was initiated from GCS)<\/span><\/font><\/div>
    b) Send vehicle target destination in RTL, Guided (allows GCS to show where vehicle is flying to in these modes)<\/span><\/font><\/div>
    c) PosHold wind compensation fix<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2 07-Nov2014 \/ 3.2-rc14 31-Oct-2014<\/span><\/font><\/div>
Changes from 3.2-rc13<\/span><\/font><\/div>
1) Safety Features:<\/span><\/font><\/div>
    a) fail to arm if second gyro calibration fails (can be disabled with ARMING_CHECK)<\/span><\/font><\/div>
2) Bug fixes:<\/span><\/font><\/div>
    a) DCM-check to require one continuous second of bad heading before triggering LAND<\/span><\/font><\/div>
    b) I2C bug that could lead to Pixhawk freezing up if I2C bus is noisy<\/span><\/font><\/div>
    c) reset DCM and EKF gyro bias estimates after gyro calibration (DCM heading could drift after takeoff due to sudden change in gyro values)<\/span><\/font><\/div>
    d) use primary GPS for LED status (instead of always using first GPS)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc13 23-Oct-2014<\/span><\/font><\/div>
Changes from 3.2-rc12<\/span><\/font><\/div>
1) DCM check triggers LAND if yaw disagrees with GPS by > 60deg (configure with DCM_CHECK_THRESH param) and in Loiter, PosHold, Auto, etc<\/span><\/font><\/div>
2) Safety features:<\/span><\/font><\/div>
    a) landing detector checks baro climbrate between -1.5 ~ +1.5 m\/s<\/span><\/font><\/div>
    b) sanity check AHRS_RP_P and AHRS_YAW_P are never less than 0.05<\/span><\/font><\/div>
    c) check set-mode requests from GCS are for this vehicle<\/span><\/font><\/div>
3) Bug fixes:<\/span><\/font><\/div>
    a) fix ch6 tuning of wp-speed (was getting stuck at zero)<\/span><\/font><\/div>
    b) parachute servo set to off position on startup<\/span><\/font><\/div>
    c) Auto Takeoff timing bug fix that could cause severe lean on takeoff<\/span><\/font><\/div>
    d) timer fix for \"slow start\" of motors on Pixhawk (timer was incorrectly based on 100hz APM2 main loop speed)<\/span><\/font><\/div>
4) reduced number of relays from 4 to 2 (saves memory and flash required on APM boards)<\/span><\/font><\/div>
5) reduced number of range finders from 2 to 1 (saves memory and flash on APM boards)<\/span><\/font><\/div>
6) allow logging from startup when LOG_BITMASK set to \"All+DisarmedLogging\"<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc12 10-Oct-2014<\/span><\/font><\/div>
Changes from 3.2-rc11<\/span><\/font><\/div>
1) disable sonar on APM1 and TradHeli (APM1 & APM2) to allow code to fit<\/span><\/font><\/div>
2) Add pre-arm and health check that gyro calibration succeeded<\/span><\/font><\/div>
3) Bug fix to EKF reporting invalid position and velocity when switched on in flight with Ch7\/Ch8 switch<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc11 06-Oct-2014<\/span><\/font><\/div>
Changes from 3.2-rc10<\/span><\/font><\/div>
1) reduce lean on take-off in Auto by resetting horizontal position targets<\/span><\/font><\/div>
2) TradHeli landing check ignores overall throttle output<\/span><\/font><\/div>
3) reduce AHRS bad messages by delaying 20sec after init to allow EKF to settle (Pixhawk only)<\/span><\/font><\/div>
4) Bug fixes:<\/span><\/font><\/div>
    a) fix THR_MIN scaling issue that could cause landing-detector to fail to detect landing when ch3 min~max > 1000 pwm<\/span><\/font><\/div>
    b) fix Mediatek GPS configuration so update rate is set correctly to 5hz<\/span><\/font><\/div>
    c) fix to Condition-Yaw mission command to support relative angles<\/span><\/font><\/div>
    d) EKF bug fixes when recovering from GPS glitches (affects only Pixhawks using EKF)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc10 24-Sep-2014<\/span><\/font><\/div>
Changes from 3.2-rc9<\/span><\/font><\/div>
1) two-stage land-detector to reduce motor run-up when landing in Loiter, PosHold, RTL, Auto<\/span><\/font><\/div>
2) Allow passthrough from input to output of channels 9 ~ 14 (thanks Emile!)<\/span><\/font><\/div>
3) Add 4hz filter to vertical velocity error during AltHold<\/span><\/font><\/div>
4) Safety Feature:<\/span><\/font><\/div>
    a) increase Alt Disparity pre-arm check threshold to 2m (was 1m)<\/span><\/font><\/div>
    b) reset battery failsafe after disarming\/arming (thanks AndKe!)<\/span><\/font><\/div>
    c) EKF only apply centrifugal corrections when GPS has at least 6 satellites (Pixhawk with EKF enabled only)<\/span><\/font><\/div>
5) Bug fixes:<\/span><\/font><\/div>
    a) to default compass devid to zero when no compass connected<\/span><\/font><\/div>
    b) reduce motor run-up while landing in RTL<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc9 11-Sep-2014<\/span><\/font><\/div>
Changes from 3.2-rc8<\/span><\/font><\/div>
1) FRAM bug fix that could stop Mission or Parameter changes from being saved (Pixhawk, VRBrain only)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc8 11-Sep-2014<\/span><\/font><\/div>
Changes from 3.2-rc7<\/span><\/font><\/div>
1) EKF reduced ripple to resolve copter motor pulsing<\/span><\/font><\/div>
2) Default Param changes:<\/span><\/font><\/div>
    a) AltHold Rate P reduced from 6 to 5<\/span><\/font><\/div>
    b) AltHold Accel P reduced from 0.75 to 0.5, I from 1.5 to 1.0<\/span><\/font><\/div>
    c) EKF check threshold increased from 0.6 to 0.8 to reduce false positives<\/span><\/font><\/div>
3) sensor health flags sent to GCS only after initialisation to remove false alerts<\/span><\/font><\/div>
4) suppress bad terrain data alerts<\/span><\/font><\/div>
5) Bug Fix:<\/span><\/font><\/div>
    a)PX4 dataflash RAM useage reduced to 8k so it works again<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc7 04-Sep-2014<\/span><\/font><\/div>
Changes from 3.2-rc6<\/span><\/font><\/div>
1) Safety Items:<\/span><\/font><\/div>
    a) Landing check made more strict (climb rate requirement reduced to 30cm\/s, overall throttle < 25%, rotation < 20deg\/sec)<\/span><\/font><\/div>
    b) pre-arm check that accels are consistent (Pixhawk only, must be within 1m\/sec\/sec of each other)<\/span><\/font><\/div>
    c) pre-arm check that gyros are consistent (Pixhawk only, must be within 20deg\/sec of each other)<\/span><\/font><\/div>
    d) report health of all accels and gyros (not just primary) to ground station<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc6 31-Aug-2014<\/span><\/font><\/div>
Changes from 3.2-rc5<\/span><\/font><\/div>
1) Spline twitch when passing through a waypoint largely resolved<\/span><\/font><\/div>
2) THR_DZ param added to allow user configuration of throttle deadzone during AltHold, Loiter, PosHold<\/span><\/font><\/div>
3) Landing check made more strict (climb rate must be -40~40cm\/s for 1 full second)<\/span><\/font><\/div>
4) LAND_REPOSITION param default set to 1<\/span><\/font><\/div>
5) TradHeli with flybar passes through pilot inputs directly to swash when in ACRO mode<\/span><\/font><\/div>
6) Safety Items:<\/span><\/font><\/div>
    a) EKF check disabled when using inertial nav (caused too many false positives)<\/span><\/font><\/div>
    b) pre-arm check of internal vs external compass direction (must be within 45deg of each other)<\/span><\/font><\/div>
7) Bug Fixes:<\/span><\/font><\/div>
    a) resolve NaN in angle targets when vehicle hits gimbal lock in ACRO mode<\/span><\/font><\/div>
    b) resolve GPS driver buffer overflow that could lead to missed GPS messages on Pixhawk\/PX4 boards<\/span><\/font><\/div>
    c) resolve false \"compass not calibrated\" warnings on Pixhawk\/PX4 caused by missing device id initialisation<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc5 15-Aug-2014<\/span><\/font><\/div>
Changes from 3.2-rc4<\/span><\/font><\/div>
1) Pixhawk's max num waypoints increased to 718<\/span><\/font><\/div>
2) Smoother take-off in AltHold, Loiter, PosHold (including removing initial 20cm jump when taking off)<\/span><\/font><\/div>
3) ACRO mode roll, pitch, yaw EXPO added for faster rotation when sticks are at extremes (see ACRO_EXPO parameter)<\/span><\/font><\/div>
4) ch7\/ch8 relay option replaces ch6 option (ch6 is reserved for tuning not switching things on\/off)<\/span><\/font><\/div>
5) Safety Items:<\/span><\/font><\/div>
    a) Baro glitch check relaxed to 5m distance, 15m\/s\/s max acceleration<\/span><\/font><\/div>
    b) EKF\/INav check relaxed to 80cm\/s\/s acceleration correct (default remains as 0.6 but this now means 80cm\/s\/s)<\/span><\/font><\/div>
    c) When GPS or Baro glitch clears, the inertial nav velocities are *not* reset reducing chance of sudden vehicle lean<\/span><\/font><\/div>
    d) Baro altitude calculation checked for divide-by-zero and infinity<\/span><\/font><\/div>
6) Bug Fixes:<\/span><\/font><\/div>
    a) AltHold jump bug fixed (altitude target reset when landed)<\/span><\/font><\/div>
    b) Rally point bug fix so it does not climb excessively before flying to rally point<\/span><\/font><\/div>
    c) body-frame rate controller z-axis bug fix (fast rotation in z-axis would cause wobble in roll, pitch)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc4 01-Aug-2014<\/span><\/font><\/div>
Changes from 3.2-rc3<\/span><\/font><\/div>
1) Pre-takeoff throttle feedback in AltHold, Loiter, PosHold<\/span><\/font><\/div>
2) Terrain altitude retrieval from ground station (informational purposes only so far, Pixhawk only)<\/span><\/font><\/div>
3) Safety Items:<\/span><\/font><\/div>
    a) \"EKF check\" will switch to LAND mode if EKF's compass or velocity variance over 0.6 (configurable with EKFCHECK_THRESH param)<\/span><\/font><\/div>
       When EKF is not used inertial nav's accelerometer corrections are used as a substitute<\/span><\/font><\/div>
    b) Barometer glitch protection added.  BAROGLTCH_DIST and BAROGLTCH_ACCEL parameters control sensitivity similar to GPSGLITCH protection<\/span><\/font><\/div>
       When glitching occurs barometer values are temporarily ignored<\/span><\/font><\/div>
    c) Throttle\/radio and battery failsafes now disarm vehicle when landed regardless of pilot's throttle position<\/span><\/font><\/div>
    d) auto-disarm extended to Drift, Sport and OF_Loiter flight modes<\/span><\/font><\/div>
    e) APM2 buzzer notification added for arming failure<\/span><\/font><\/div>
    f) APM2 arming buzz made longer (now matches Pixhawk)<\/span><\/font><\/div>
    g) do-set-servo commands cannot interfere with motor output<\/span><\/font><\/div>
4) Bug Fixes:<\/span><\/font><\/div>
    a) Drift slow yaw response fixed<\/span><\/font><\/div>
    b) AC3.2-rc3 failsafe bug resolved.  In -rc3 the throttle failsafe could be triggered even when disabled or motors armed (although vehicle would not takeoff)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc3 16-Jul-2014<\/span><\/font><\/div>
Changes from 3.2-rc2<\/span><\/font><\/div>
1) Hybrid renamed to PosHold<\/span><\/font><\/div>
2) Sonar (analog, i2c) and PulsedLight Range Finders enabled on Pixhawk (Allyson, Tridge)<\/span><\/font><\/div>
3) Landing changes:<\/span><\/font><\/div>
    a) disable pilot repositioning while landing in RTL, Auto (set LAND_REPOSITION to 1 to re-enable) (JonathanC)<\/span><\/font><\/div>
    b) delay 4 seconds before landing due to failsafe (JonathanC)<\/span><\/font><\/div>
4) Secondary compass calibration enabled, pre-arm check that offsets match current devices (Randy, Tridge, MichaelO)<\/span><\/font><\/div>
5) Control improvements:<\/span><\/font><\/div>
    a) use bias adjusted gyro rates - helps in cases of severe gyro drift (Jonathan)<\/span><\/font><\/div>
    b) bug-fixes when feed-forward turned off (Leonard)<\/span><\/font><\/div>
6) TradHeli improvements (RobL):<\/span><\/font><\/div>
    a) bug fix to use full collective range in stabilize and acro flight modes<\/span><\/font><\/div>
    b) filter added to main rotor input (ch8) to ensure momentary blip doesn't affect main rotor speed<\/span><\/font><\/div>
7) Safety items:<\/span><\/font><\/div>
    a) increased default circular Fence radius to 300m to reduce chance of breach when GPS lock first acquired<\/span><\/font><\/div>
    b) radio failsafe timeout for late frames reduced to 0.5sec for normal receivers or 2.0sec when flying with joystick (Craig)<\/span><\/font><\/div>
    c) accelerometer pre-arm check for all active accelerometers (previously only checked the primary accelerometer)<\/span><\/font><\/div>
8) Other features:<\/span><\/font><\/div>
    a) ch7\/ch8 option to retract mount (svefro)<\/span><\/font><\/div>
    b) Do-Set-ROI supported in Guided, RTL mode<\/span><\/font><\/div>
    c) Condition-Yaw accepted in Guided, RTL modes (MoussSS)<\/span><\/font><\/div>
    d) CAMERA dataflash message includes relative and absolute altitude (Craig)<\/span><\/font><\/div>
9) Red Balloon Popper support (Randy, Leonard):<\/span><\/font><\/div>
    a) Velocity controller added to Guided mode<\/span><\/font><\/div>
    b) NAV_GUIDED mission command added<\/span><\/font><\/div>
10) Bug fixes:<\/span><\/font><\/div>
    a) bug fix to flip on take-off in stabilize mode when landing flag cleared slowly (JonathanC)<\/span><\/font><\/div>
    b) allow disarming in AutoTune (JonathanC)<\/span><\/font><\/div>
    c) bug fix to unpredictable behaviour when two spline points placed directly ontop of each other<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc2 27-May-2014<\/span><\/font><\/div>
Changes from 3.2-rc1<\/span><\/font><\/div>
1) Hybrid mode initialisation bug fix<\/span><\/font><\/div>
2) Throttle pulsing bug fix on Pixhawk<\/span><\/font><\/div>
3) Parachute enabled on Pixhawk<\/span><\/font><\/div>
4) Rally Points enabled on Pixhawk<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.2-rc1 9-May-2014<\/span><\/font><\/div>
Changes from 3.1.4<\/span><\/font><\/div>
1) Hybrid mode - position hold mode but with direct response to pilot input during repositioning (JulienD, SandroT)<\/span><\/font><\/div>
2) Spline waypoints (created by David Dewey, modified and integrated by Leonard, Randy)<\/span><\/font><\/div>
3) Drift mode uses \"throttle assist\" for altitude control (Jason)<\/span><\/font><\/div>
4) Extended Kalman Filter for potentially more reliable attitude and position control (Pixhawk only) (Paul Riseborough).  Set AHRS_EKF_USE to 1 to enable or use Ch7\/8 switch to enable\/disable in flight.<\/span><\/font><\/div>
5) Manual flight smoothness:<\/span><\/font><\/div>
    a) Smoother roll, pitch response using RC_FEEL_RP parameter (100 = crisp, 0 = extremely soft)<\/span><\/font><\/div>
    b) Adjustable max rotation rate (ATC_RATE_RP_MAX, ATC_RATE_Y_MAX) and acceleration (ATC_ACCEL_RP_MAX, ATC_ACCEL_Y_MAX)<\/span><\/font><\/div>
6) Autopilot smoothness:<\/span><\/font><\/div>
    a) Vertical acceleration in AltHold, Loiter, Hybrid modes can be configured with PILOT_ACCEL_Z parameter (higher = faster acceleration)<\/span><\/font><\/div>
    b) Maximum roll and pitch angle acceleration in Loiter mode can be configured with WPNAV_LOIT_JERK (higher = more responsive but potentially jerky)<\/span><\/font><\/div>
    c) Yaw speed can be adjusted with ATC_SLEW_YAW parameter (higher = faster)<\/span><\/font><\/div>
    d) smoother takeoff with configurable acceleration using WPNAV_ACCEL_Z parameter<\/span><\/font><\/div>
    e) Twitches removed during guided mode or when entering Loiter or RTL from high speeds<\/span><\/font><\/div>
7) Mission improvements:<\/span><\/font><\/div>
    a) mission will be resumed from last active command when pilot switches out and then back into Auto mode (prev behaviour can be restored by setting MIS_RESTART param to 1)<\/span><\/font><\/div>
    b) DO_SET_ROI persistent across waypoints.  All-zero DO_SET_ROI command restores default yaw behaviour<\/span><\/font><\/div>
    c) do-jump fixed<\/span><\/font><\/div>
    d) conditional_distance fixed<\/span><\/font><\/div>
    e) conditional_delay fixed<\/span><\/font><\/div>
    f) do-change-speed command takes effect immediately during mission<\/span><\/font><\/div>
    g) vehicle faces directly at next waypoint (previously it could be about 10deg off)<\/span><\/font><\/div>
    h) loiter turns fix to ensure it will circle around lat\/lon point specified in mission command (previously it could be off by CIRCLE_RADIUS)<\/span><\/font><\/div>
8) Safety improvements:<\/span><\/font><\/div>
    a) After a fence breach, if the pilot re-takes control he\/she will be given a minimum of 10 seconds and 20m to recover before the autopilot will invoke RTL or LAND<\/span><\/font><\/div>
    b) Parachute support including automatic deployment during mechanical failures<\/span><\/font><\/div>
9) Other enhancements:<\/span><\/font><\/div>
    a) V-tail quad support<\/span><\/font><\/div>
    b) Dual GPS support (secondary GPS output is simply logged, not actually used yet)<\/span><\/font><\/div>
    c) Electro Permanent Magnet (aka Gripper) support<\/span><\/font><\/div>
    d) Servo pass through for channels 6 ~ 8 (set RC6_FUNCTION to 1)<\/span><\/font><\/div>
    e) Remove 80m limit on RTL's return altitude but never let it be above fence's max altitude<\/span><\/font><\/div>
10) Other bug fixes:<\/span><\/font><\/div>
    a) Bug fix for LAND sometimes getting stuck at 10m<\/span><\/font><\/div>
    b) During missions, vehicle will maintain altitude even if WPNAV_SPEED is set above the vehicle's capabilities<\/span><\/font><\/div>
    c) when autopilot controls throttle (i.e. Loiter, Auto, etc) vehicle will reach speeds specified in PILOT_VELZ_MAX and WPNAV_SPEED_UP, WPNAV_SPEED_DN parameters<\/span><\/font><\/div>
11) CLI removed from APM1\/2 to save flash space, critical functions moved to MAVLink:<\/span><\/font><\/div>
    a) Individual motor tests (see MP's Initial Setup > Optional Hardware > Motor Test)<\/span><\/font><\/div>
    b) compassmot (see MP's Initial Setup > Optional Hardware > Compass\/Motor Calib)<\/span><\/font><\/div>
    c) parameter reset to factory defautls (see MP's Config\/Tuning > Full Parameter List > Reset to Default)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.5 27-May-2014 \/ 3.1.5-rc2 20-May-2014<\/span><\/font><\/div>
Changes from 3.1.5-rc1<\/span><\/font><\/div>
1) Bug Fix to broken loiter (pixhawk only)<\/span><\/font><\/div>
2) Workaround to read from FRAM in 128byte chunks to resolve a few users boot issues (Pixhawk only)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.5-rc1 14-May-2014<\/span><\/font><\/div>
Changes from 3.1.4<\/span><\/font><\/div>
1) Bug Fix to ignore roll and pitch inputs to loiter controller when in radio failsafe<\/span><\/font><\/div>
2) Bug Fix to allow compassmot to work on Pixhawk<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.4 8-May-2014 \/ 3.1.4-rc1 2-May-2014<\/span><\/font><\/div>
Changes from 3.1.3<\/span><\/font><\/div>
1) Bug Fix for Pixhawk\/PX4 NuttX I2C memory corruption when errors are found on I2C bus<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.3 7-Apr-2014<\/span><\/font><\/div>
Changes from 3.1.2<\/span><\/font><\/div>
1) Stability patch fix which could cause motors to go to min at full throttle and with large roll\/pitch inputs<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.2 13-Feb-2014 \/ ArduCopter 3.1.2-rc2 12-Feb-2014<\/span><\/font><\/div>
Changes from 3.1.2-rc1<\/span><\/font><\/div>
1) GPS Glitch detection disabled when connected via USB<\/span><\/font><\/div>
2) RC_FEEL_RP param added for adjusting responsiveness to pilot roll\/pitch input in Stabilize, Drift, AltHold modes<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.2-rc1 30-Jan-2014<\/span><\/font><\/div>
Changes from 3.1.1<\/span><\/font><\/div>
1) Pixhawk baro bug fix to SPI communication which could cause large altitude estimate jumps at high temperatures<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.1 26-Jan-2014 \/ ArduCopter 3.1.1-rc2 21-Jan-2014<\/span><\/font><\/div>
Changes from 3.1.1-rc1<\/span><\/font><\/div>
1) Pixhawk improvements (available for APM2 when AC3.2 is released):<\/span><\/font><\/div>
    a) Faster arming<\/span><\/font><\/div>
    b) AHRS_TRIM fix - reduces movement in loiter when yawing<\/span><\/font><\/div>
    c) AUX Out 5 & 6 turned into general purpose I\/O pins<\/span><\/font><\/div>
    d) Three more relays added (relays are pins that can be set to 0V or 5V)<\/span><\/font><\/div>
    e) do-set-servo fix to allow servos to be controlled from ground station<\/span><\/font><\/div>
    f) Motorsync CLI test<\/span><\/font><\/div>
    g) PX4 parameters moved from SD card to eeprom<\/span><\/font><\/div>
    h) additional pre-arm checks for baro & inertial nav altitude and lean angle<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1.1-rc1 14-Jan-2014<\/span><\/font><\/div>
Changes from 3.1<\/span><\/font><\/div>
1) Pixhawk improvements:<\/span><\/font><\/div>
    a) Telemetry port 2 enabled (for MinimOSD)<\/span><\/font><\/div>
    b) SD card reliability improvements<\/span><\/font><\/div>
    c) parameters moved to FRAM<\/span><\/font><\/div>
    d) faster parameter loading via USB<\/span><\/font><\/div>
    e) Futaba SBUS receiver support<\/span><\/font><\/div>
2) Bug fixes:<\/span><\/font><\/div>
    a) Loiter initialisation fix (Loiter would act like AltHold until flight mode switch changed position)<\/span><\/font><\/div>
    b) ROI commands were not returning Lat, Lon, Alt to mission planner when mission was loaded from APM<\/span><\/font><\/div>
3) TradHeli only fixes:<\/span><\/font><\/div>
    a) Drift now uses same (reduced) collective range as stabilize mode<\/span><\/font><\/div>
    b) AutoTune disabled (for tradheli only)<\/span><\/font><\/div>
    c) Landing collective (smaller than normal collective) used whenever copter is not moving<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1 14-Dec-2013<\/span><\/font><\/div>
Changes from 3.1-rc8<\/span><\/font><\/div>
1) Pixhawk improvements:<\/span><\/font><\/div>
    a) switch to use MPU6k as main accel\/gyro<\/span><\/font><\/div>
    b) auto loading of IO-board firmware on startup<\/span><\/font><\/div>
2) RTL fixes:<\/span><\/font><\/div>
    a) initialise waypoint leash length (first RTL stop would be more aggressive than 2nd)<\/span><\/font><\/div>
    b) reduce projected stopping distance for higher speed stops<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc8 9-Dec-2013<\/span><\/font><\/div>
Changes from 3.1-rc7<\/span><\/font><\/div>
1) add Y6 motor mapping with all top props CW, bottom pros CCW (set FRAME = 10)<\/span><\/font><\/div>
2) Safety Changes:<\/span><\/font><\/div>
    a) ignore yaw input during radio failsafe (previously the copter could return home spinning if yaw was full over at time of failsafe)<\/span><\/font><\/div>
    b) Reduce GPSGLITCH_RADIUS to 2m (was 5m) to catch glitches faster<\/span><\/font><\/div>
3) Bug fixes:<\/span><\/font><\/div>
    a) Optical flow SPI bus rates<\/span><\/font><\/div>
    b) TradHeli main rotor ramp up speed fix<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc7 22-Nov-2013<\/span><\/font><\/div>
Changes from 3.1-rc6<\/span><\/font><\/div>
1) MOT_SPIN_ARMED default to 70<\/span><\/font><\/div>
2) Smoother inertial nav response to missed GPS messages<\/span><\/font><\/div>
3) Safety related changes<\/span><\/font><\/div>
    a) radio and battery failsafe disarm copter if landed in Loiter or AltHold (previously they would RTL)<\/span><\/font><\/div>
    b) Pre-Arm check failure warning output to ground station every 30 seconds until they pass<\/span><\/font><\/div>
    c) INS and inertial nav errors logged to dataflash's PM message<\/span><\/font><\/div>
    d) pre-arm check for ACRO_BAL_ROLL, ACRO_BAL_PITCH<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc6 16-Nov-2013<\/span><\/font><\/div>
Improvements over 3.1-rc5<\/span><\/font><\/div>
1) Heli improvements:<\/span><\/font><\/div>
    a) support for direct drive tails (uses TAIL_TYPE and TAIL_SPEED parameters)<\/span><\/font><\/div>
    b) smooth main rotor ramp-up for those without external govenor (RSC_RAMP_TIME)<\/span><\/font><\/div>
    c) internal estimate of rotor speed configurable with RSC_RUNUP_TIME parameter to ensure rotor at top speed before starting missions<\/span><\/font><\/div>
    d) LAND_COL_MIN collective position used when landed (reduces chance copter will push too hard into the ground when landing or before starting missions)<\/span><\/font><\/div>
    e) reduced collective while in stabilize mode (STAB_COL_MIN, STAB_COL_MAX) for more precise throttle control<\/span><\/font><\/div>
    f) external gyro parameter range changed from 1000~2000 to 0~1000 (more consistent with other parameters)<\/span><\/font><\/div>
    g) dynamic flight detector switches on\/off leaky-i term depending on copter speed<\/span><\/font><\/div>
2) SingleCopter airframe support (contribution from Bill King)<\/span><\/font><\/div>
3) Drift mode replaces TOY<\/span><\/font><\/div>
4) MPU6k SPI bus speed decreased to 500khz after 4 errors<\/span><\/font><\/div>
5) Safety related changes:<\/span><\/font><\/div>
    a) crash detector cuts motors if copter upside down for more than 2 seconds<\/span><\/font><\/div>
    b) INS (accel and gyro) health check in pre-arm checks<\/span><\/font><\/div>
    c) ARMING_CHECK allows turning on\/off individual checks for baro, GPS, compass, parameters, board voltage, radio<\/span><\/font><\/div>
    d) detect Ublox GPS running at less than 5hz and resend configuration<\/span><\/font><\/div>
    e) GPSGlitch acceptable radius reduced to 5m (stricter detection of glitches)<\/span><\/font><\/div>
    f) range check roll, pitch input to ensure crazy radio values don't get through to stabilize controller<\/span><\/font><\/div>
    g) GPS failsafe options to trigger AltHold instead of LAND or to trigger LAND even if in flight mode that does not require GPS<\/span><\/font><\/div>
    h) Battery failsafe option to trigger RTL instead of LAND<\/span><\/font><\/div>
    i) MOT_SPIN_ARMED set to zero by default<\/span><\/font><\/div>
6) Bug fixes:<\/span><\/font><\/div>
    a) missing throttle controller initialisation would mean Stabilize mode's throttle could be non-tilt-compensated<\/span><\/font><\/div>
    b) inertial nav baro and gps delay compensation fix (contribution from Neurocopter)<\/span><\/font><\/div>
    c) GPS failsafe was invoking LAND mode which still used GPS for horizontal control<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc5 22-Oct-2013<\/span><\/font><\/div>
Improvements over 3.1-rc4<\/span><\/font><\/div>
1) Pixhawk USB reliability improvements<\/span><\/font><\/div>
2) AutoTune changes:<\/span><\/font><\/div>
    a) enabled by default<\/span><\/font><\/div>
    b) status output to GCS<\/span><\/font><\/div>
    c) use 2 pos switch only<\/span><\/font><\/div>
3) ch7\/ch8 LAND<\/span><\/font><\/div>
4) Tricopter stability patch improvements [thanks to texlan]<\/span><\/font><\/div>
5) safety improvements:<\/span><\/font><\/div>
    a) slower speed up of motors after arming<\/span><\/font><\/div>
    b) pre-arm check that copter is moving less than 50cm\/s if arming in Loiter or fence enabled<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc4 13-Oct-2013<\/span><\/font><\/div>
Improvements over 3.1-rc3<\/span><\/font><\/div>
1) Performance improvements to resolve APM alt hold issues for Octacopters:<\/span><\/font><\/div>
     a) SPI bus speed increased from 500khz to 8Mhz<\/span><\/font><\/div>
     b) Telemetry buffer increased to 512bytes<\/span><\/font><\/div>
     c) broke up medium and slow loops into individual scheduled tasks and increased priority of alt hold tasks<\/span><\/font><\/div>
2) Bug fix for Pixhawk USB connection<\/span><\/font><\/div>
3) GPS Glitch improvements:<\/span><\/font><\/div>
       a) added GPS glitch check to arming check<\/span><\/font><\/div>
       b) parameters for vehicle max acceleration (GPSGLITCH_ACCEL) and always-ok radius (GPSGLICH_RADIUS)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc3 09-Oct-2013<\/span><\/font><\/div>
Improvements over 3.1-rc2<\/span><\/font><\/div>
1) GPS Glitch protection - gps positions are compared with the previous gps position.  Position accepted if within 10m or copter could have reached the position with max accel of 10m\/s\/s.<\/span><\/font><\/div>
2) Bug fix for pixhawk SPI bus contention that could lead to corrupted accelerometer values on pixhawk resolved<\/span><\/font><\/div>
3) Auto Tuning (compile time option only add \"#define AUTOTUNE ENABLED\" to APM_Config.h and set CH7_Opt or CH8_Opt parameter to 17)<\/span><\/font><\/div>
4) CPU Performance improvement when reading from MPU6k for APM<\/span><\/font><\/div>
5) SUPER_SIMPLE parameter changed to a bit map to allow some flight modes to use super simpler while others use regular simple (MP release to allow easier selection will go out with AC3.1 official release)<\/span><\/font><\/div>
6) Safety changes:<\/span><\/font><\/div>
    a) safety button must be pushed before arming on pixhawk<\/span><\/font><\/div>
    b) RGB LED (aka toshiba led) changed so that disarmed flashes, armed is either blue (if no gps lock) or green (if gps lock)<\/span><\/font><\/div>
    c) sensor health bitmask sent to groundstations<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc2 18-Sep-2013<\/span><\/font><\/div>
Improvements over 3.1-rc1<\/span><\/font><\/div>
1) bug fix for MOT_SPIN_ARMED to allow it to be higher than 127<\/span><\/font><\/div>
2) PX4\/pixhawk auto-detect internal\/external compass so COMPASS_ORIENT should be set to ORIENTATION_NONE if using GPS+compass module<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.1-rc1 9-Sep-2013<\/span><\/font><\/div>
Improvements over 3.0.1<\/span><\/font><\/div>
1) Support for Pixhawks board<\/span><\/font><\/div>
2) Arm, Disarm, Land and Takeoff in Loiter and AltHold<\/span><\/font><\/div>
3) Improved Acro<\/span><\/font><\/div>
    a) ACRO_RP_P, ACRO_YAW_P parameters added to control speed of rotation<\/span><\/font><\/div>
    b) ACRO_BAL_ROLL, ACRO_BAL_PITCH controls speed at which copter returns to level<\/span><\/font><\/div>
    c) ACRO_TRAINER can be set to 0:disable trainer, 1:auto leveling when sticks released, 2:auto leveling and lean angle limited to ANGLE_MAX<\/span><\/font><\/div>
    d) Ch7 & Ch8 switch to set ACRO_TRAINER options in-flight<\/span><\/font><\/div>
4) SPORT mode - equivalent of earth frame Acro with support for simple mode<\/span><\/font><\/div>
5) Sonar ground tracking improvements and bug fixes that reduce reaction to bad sonar data<\/span><\/font><\/div>
6) Safety improvements<\/span><\/font><\/div>
    a) motors always spin when armed (speed can be controlled with MOT_SPIN_ARMED, set to 0 to disable)<\/span><\/font><\/div>
    b) vehicle's maximum lean angle can be reduced (or increased) with the ANGLE_MAX parameter<\/span><\/font><\/div>
    c) arming check that GPS hdop is > 2.0 (disable by setting GPS_HDOP parameter to 900)<\/span><\/font><\/div>
    d) slow take-off in AUTO, LOITER, ALTHOLD to reduce chance of motor\/esc burn-out on large copters<\/span><\/font><\/div>
7) Bug fixes:<\/span><\/font><\/div>
    a) Optical flow sensor initialisation fix<\/span><\/font><\/div>
    b) altitude control fix for Loiter_turns mission command (i.e. mission version of CIRCLE mode)<\/span><\/font><\/div>
    c) DO_SET_ROI fix (do not use \"ROI\")<\/span><\/font><\/div>
8) Distribute Loiter & Navigation calcs over 4 cycles to reduce impact on a single 100hz loop<\/span><\/font><\/div>
9) RCMAP_ parameters allow remapping input channels 1 ~ 4<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.1-rc2 \/ 3.0.1 11-Jul-2013<\/span><\/font><\/div>
Improvements over 3.0.1-rc1<\/span><\/font><\/div>
1) Rate Roll, Pitch and Yaw I fix when we hit motor limits<\/span><\/font><\/div>
2) pre-arm check changes:<\/span><\/font><\/div>
    a) double flash arming light when pre-arm checks fail<\/span><\/font><\/div>
    b) relax mag field checks to 35% min, 165% max of expected field<\/span><\/font><\/div>
3) loiter and auto changes:<\/span><\/font><\/div>
      a) reduced Loiter speed to 5 m\/s<\/span><\/font><\/div>
      b) reduced WP_ACCEL to 1 m\/s\/s (was 2.5 m\/s\/s)<\/span><\/font><\/div>
      c) rounding error fix in loiter controller<\/span><\/font><\/div>
      d) bug fix to stopping point calculation for RTL and loiter during missions<\/span><\/font><\/div>
4) Stability Patch fix which was freezing Rate Taw I term and allowing uncommanded Yaw<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.1-rc1 26-Jun-2013<\/span><\/font><\/div>
Improvements over 3.0.0<\/span><\/font><\/div>
1) bug fix to Fence checking position after GPS lock was lost<\/span><\/font><\/div>
2) bug fix to LAND so that it does not attempt to maintain horizontal position without GPS lock<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0 \/ 3.0.0-rc6 16-Jun-2013<\/span><\/font><\/div>
Improvements over 3.0.0-rc5<\/span><\/font><\/div>
1) bug fix to Circle mode's start position (was moving to last loiter target)<\/span><\/font><\/div>
2) WP_ACCEL parameter added to allow user to adjust acceleration during missions<\/span><\/font><\/div>
3) loiter acceleration set to half of LOIT_SPEED parameter value (was hard-coded)<\/span><\/font><\/div>
4) reduce AltHold P to 1.0 (was 2.0)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0-rc5 04-Jun-2013<\/span><\/font><\/div>
Improvements over 3.0.0-rc4<\/span><\/font><\/div>
1) bug fix to LAND flight mode in which it could try to fly to mission's next waypoint location<\/span><\/font><\/div>
2) bug fix to Circle mode to allow counter-clockwise rotation<\/span><\/font><\/div>
3) bug fix to heading change in Loiter, RTL, Missions when pilot's throttle is zero<\/span><\/font><\/div>
4) bug fix for mission sticking at take-off command when pilot's throttle is zero<\/span><\/font><\/div>
5) bug fix for parameters not saving when new value is same as default value<\/span><\/font><\/div>
6) reduce pre-arm board min voltage check to 4.3V (was 4.5V)<\/span><\/font><\/div>
7) remove throttle controller's ability to limit lean angle in loiter, rtl, auto<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0-rc4 02-Jun-2013<\/span><\/font><\/div>
Improvements over 3.0.0-rc3<\/span><\/font><\/div>
1) loiter improvements:<\/span><\/font><\/div>
     i) repositioning enhanced with feed forward<\/span><\/font><\/div>
     ii) use tan to convert desired accel to lean angle<\/span><\/font><\/div>
2) stability patch improvements for high powered copters or those with roll-pitch rate gains set too high<\/span><\/font><\/div>
3) auto mode vertical speed fix (it was not reaching the desired speeds)<\/span><\/font><\/div>
4) alt hold smoothed by filtering feed forward input<\/span><\/font><\/div>
5) circle mode fix to initial position and smoother initialisation<\/span><\/font><\/div>
6) RTL returns to initial yaw heading before descending<\/span><\/font><\/div>
7) safe features:<\/span><\/font><\/div>
    i) check for gps lock when entering failsafe<\/span><\/font><\/div>
    ii) pre-arm check for mag field lenght<\/span><\/font><\/div>
    iii) pre-arm check for board voltage between 4.5v ~ 5.8V<\/span><\/font><\/div>
    iv) beep twice during arming<\/span><\/font><\/div>
    v) GPS failsafe enabled by default (will LAND if loses GPS in Loiter, AUTO, Guided modes)<\/span><\/font><\/div>
    vi) bug fix for alt-hold mode spinning motors before pilot has raised throttle<\/span><\/font><\/div>
8) bug fixes:<\/span><\/font><\/div>
    i) fixed position mode so it responding to pilot input<\/span><\/font><\/div>
    ii) baro cli test<\/span><\/font><\/div>
    iii) moved cli motor test to test sub menu and minor change to throttle output<\/span><\/font><\/div>
    iv) guided mode yaw control fix<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0-rc3 22-May-2013<\/span><\/font><\/div>
Improvements over 3.0.0-rc2<\/span><\/font><\/div>
1) bug fix for dataflash erasing unnecessarily<\/span><\/font><\/div>
2) smoother transition to waypoints, loiter:<\/span><\/font><\/div>
    intermediate point's speed initialised from copter's current speed<\/span><\/font><\/div>
3) Ch8 auxiliary function switch (same features as Ch7)<\/span><\/font><\/div>
4) safety checks:<\/span><\/font><\/div>
    Warning to GCS of reason for pre-arm check failure<\/span><\/font><\/div>
    ARMING_CHECK parameter added to allow disabling pre-arm checks<\/span><\/font><\/div>
    Added compass health and offset check to pre-arm check<\/span><\/font><\/div>
    compassmot procedure displays interference as percentage of total mag field<\/span><\/font><\/div>
5) WPNAV dataflash message combined into NTUN message<\/span><\/font><\/div>
6) allow TriCopters to use ESC calibration<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0-rc2 13-May-2013<\/span><\/font><\/div>
Improvements over 3.0.0-rc1:<\/span><\/font><\/div>
1) smoother transition to waypoints, loiter:<\/span><\/font><\/div>
    reduced loiter max acceleration to smooth waypoints<\/span><\/font><\/div>
    bug fix to uninitialised roll\/pitch when entering RTL, AUTO, LOITER<\/span><\/font><\/div>
2) fast waypoints - copter does not stop at waypoints unless delay is specified<\/span><\/font><\/div>
3) WPNAV_LOIT_SPEED added to allow faster\/slower loiter repositioning<\/span><\/font><\/div>
4) removed speed limits on auto missions<\/span><\/font><\/div>
5) enhance LAND mission command takes lat\/lon coordinates<\/span><\/font><\/div>
6) bug fix for RTL not pointing home sometimes<\/span><\/font><\/div>
7) centrifugal correction disabled when copter is disarmed to stop HUD moving<\/span><\/font><\/div>
8) centrifugal correction disabled when sat count less than 6 (AHRS_GPS_MINSATS)<\/span><\/font><\/div>
9) compass calibration reliability improvements when run from mission planner<\/span><\/font><\/div>
10) bug fix to allow compassmot to be run from mission planner terminal screen<\/span><\/font><\/div>
11) add support for H-quad frame<\/span><\/font><\/div>
12) add COMPASS_ORIENT parameter to support external compass in any orientation<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 3.0.0-rc1 01-May-2013<\/span><\/font><\/div>
Improvements over 2.9.1b:<\/span><\/font><\/div>
1) Inertial navigation for X & Y axis (Randy\/Leonard\/Jonathan)<\/span><\/font><\/div>
2) 3D waypoint navigation library (Leonard\/Randy)<\/span><\/font><\/div>
    WPNAV_SPEED, WPNAV_SPEED_UP, WPNAV_SPEED_DN control target speeds during missions and RTL<\/span><\/font><\/div>
    WP_YAW_BEHAVIOR to allow disabling yaw during missions and RTL<\/span><\/font><\/div>
3) PX4 support (some features still not available) (Tridge\/Pat\/PX4Dev Team)<\/span><\/font><\/div>
4) Safety improvements:<\/span><\/font><\/div>
    Tin-can shaped fence (set FENCE_ENABLED to 1 and copter will RTL if alt > 150m or horizontal distance from home > 300m) (Randy\/Tridge\/Leonard)<\/span><\/font><\/div>
    GCS failsafe (set FS_GCS_ENABLED to 1 and if you are using a tablet to fly your copter it will RTL and return control to the radio 3 seconds after losing telemetry) (Randy)<\/span><\/font><\/div>
    pre-arm checks to ensure accelerometer and radio calibration has been performed before arming (Randy)<\/span><\/font><\/div>
5) motor interference compensation for compass (Jonathan\/Randy)<\/span><\/font><\/div>
6) Circle mode improvements:<\/span><\/font><\/div>
    set CIRCLE_RADIUS to zero to do panorama shots in circle mode (copter does not move in a circle but instead slowly rotates)<\/span><\/font><\/div>
    CIRCLE_RATE parameter allows controlling direction and speed of rotation in CIRCLE mode and LOITER_TURNS (can also be adjusted in flight from CH6 knob)<\/span><\/font><\/div>
7) SONAR_GAIN parameter add to allow reducing the response to objects sensed by sonar (Randy)<\/span><\/font><\/div>
8) support for trapezoidal quads (aka V shaped or FPV quads) (Leonard\/Craig)<\/span><\/font><\/div>
9) performance improvements to dataflash logging (Tridge)<\/span><\/font><\/div>
10) bug-fix to analog read which could cause bad sonar reads when using voltage or current monitor (Tridge)<\/span><\/font><\/div>
11) bug-fix to motors going to minimum when throttle is low while switching into Loiter, AUTO, RTL, ALT_HOLD (Jason\/Randy)<\/span><\/font><\/div>
12) bug-fix for auto disarm sometimes disarming shortly after arming (Jason\/SirAlex)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9.1b 30-Feb-2013<\/span><\/font><\/div>
Improvements over 2.9.1:<\/span><\/font><\/div>
1) reduce INS_MPU6K_FILTER to 20hz<\/span><\/font><\/div>
2) reduce InertialNav Z-axis time constant to 5 (was 7)<\/span><\/font><\/div>
3) increased max InertialNav accel correction to 3 m\/s (was 1m\/s)<\/span><\/font><\/div>
4) bug fix for alt_hold being passed as int16_t to get_throttle_althold_with_slew<\/span><\/font><\/div>
5) bug fix for throttle after acro flip (was being kept at min throttle if pilot switched out of ACRO mode while inverted)<\/span><\/font><\/div>
6) reduce yaw_rate P default to 0.20 (was 0.25)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9.1 & 2.9.1-rc2 01-Feb-2013<\/span><\/font><\/div>
Improvements over 2.9.1-rc1:<\/span><\/font><\/div>
1) small corretion to use of THR_MID to scale lower end of manual throttle between THR_MIN and 500 instead of 0 and 500<\/span><\/font><\/div>
2) bug fix for longitude scaling being incorrectly calculated using Next Waypoint instead of home which could lead to scaling being 1<\/span><\/font><\/div>
3) ESC calibration change to set update rate to ESCs to 50hz to allow simonk ESC to be calibrated<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9.1-rc1 31-Jan-2013<\/span><\/font><\/div>
Improvements over 2.9:<\/span><\/font><\/div>
1) THR_MID parameter added to allow users to adjust the manual throttle so that vehicle hovers at about mid stick<\/span><\/font><\/div>
2) bug fix for autotrim - roll axis was backwards<\/span><\/font><\/div>
3) bug fix to set sonar_alt_health to zero when sonar is disabled<\/span><\/font><\/div>
4) capture level roll and pitch trims as part of accel calibration<\/span><\/font><\/div>
5) bug fix to ppm encoder false positives<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9 & 2.9-rc5 14-Jan-2013<\/span><\/font><\/div>
Improvements over 2.9-rc4:<\/span><\/font><\/div>
1) add constraint to loiter commanded roll and pitch angles<\/span><\/font><\/div>
2) relax altitude requirement for take-off command to complete<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9-rc4 12-Jan-2013<\/span><\/font><\/div>
Improvements over 2.9-rc3:<\/span><\/font><\/div>
1) Smoother transition between manual and auto flight modes (Leonard)<\/span><\/font><\/div>
2) bug fix for LAND not actually landing when initiated from failsafe (Randy\/Craig)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9-rc3 11-Jan-2013<\/span><\/font><\/div>
Improvements over 2.9-rc2:<\/span><\/font><\/div>
1) alt hold with sonar improvements - now on by default (Leonard\/Randy)<\/span><\/font><\/div>
2) performance and memory useage improvements (Tridge\/Randy)<\/span><\/font><\/div>
3) increase APM1 baro pressure read from 5hz to 8.3hz to improve alt hold (Randy)<\/span><\/font><\/div>
4) bug fix: altitude error reported to GCS (Randy)<\/span><\/font><\/div>
5) limit inertial nav's max accel offset correction to 100cm\/s\/s to speed up recovery after hard impacts (Randy)_<\/span><\/font><\/div>
6) moved rate controllers to run after ins read (Tridge\/Randy)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9-rc2 31-Dec-2012<\/span><\/font><\/div>
Improvements over 2.9-rc1:<\/span><\/font><\/div>
1) increased throttle rate gains from 1.0 to 6.0<\/span><\/font><\/div>
2) APM1 fix so it works with inertial nav (5hz update rate of baro was beyond the tolerance set in the inav library)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.9-rc1 23-Dec-2012<\/span><\/font><\/div>
Improvements over 2.8.1:<\/span><\/font><\/div>
1) altitude hold improvements:<\/span><\/font><\/div>
    a)inertial navigation for vertical axis [Randy\/Jonathan\/Leonard\/Jason]<\/span><\/font><\/div>
    b)accel based throttle controller [Leonard\/Randy]<\/span><\/font><\/div>
    c)accelerometer calibration routine updated to use gauss-newton method [Randy\/Tridge\/Rolfe Schmidt]<\/span><\/font><\/div>
    d)parameters to control climb rate:<\/span><\/font><\/div>
        AUTO_VELZ_MIN, AUTO_VELZ_MAX - allows you to control the maximum climb and descent rates of the autopilot (in cm\/s)<\/span><\/font><\/div>
        PILOT_VELZ_MAX - allows you to control the maximum climb\/descent rate when in alt hold or loiter (in cm\/s)<\/span><\/font><\/div>
2) landing improvements [Leonard\/Randy]<\/span><\/font><\/div>
    LAND_SPEED - allows you to set the landing speed in cm\/s<\/span><\/font><\/div>
3) camera related improvements:<\/span><\/font><\/div>
    a) AP_Relay enabled for APM2 and integrated with AP_Camera [Sandro Benigno]<\/span><\/font><\/div>
    b) camera trigger with channel 7 switch or DO_DIGICAM_CONTROL mission command [Randy]<\/span><\/font><\/div>
    c) allow yaw override by pilot or with CONDITIONAL_YAW command during missions [Randy]<\/span><\/font><\/div>
        YAW_OVR_BEHAVE - Controls when autopilot takes back normal control of yaw after pilot overrides (0=after next wp, 1=never)<\/span><\/font><\/div>
4) trad heli improvements [Rob]<\/span><\/font><\/div>
    a) code tested and brought back into the fold (2.8.1 was never released for trad helis)<\/span><\/font><\/div>
    b) enabled rate controller (previously only used angle controllers)<\/span><\/font><\/div>
    c) fix to rotor speed controllers - now operates by switching off channel 8<\/span><\/font><\/div>
    d) allow wider collective pitch range in acro and alt hold modes vs stabilize mode<\/span><\/font><\/div>
    e) removed angle boost function because it created more problems than it solved<\/span><\/font><\/div>
    f) bug fix to allow collective pitch to use the entire range of servos<\/span><\/font><\/div>
5) mediatek gps driver improvements [Craig]<\/span><\/font><\/div>
    a) added support for 1.9 firmware<\/span><\/font><\/div>
    b) bug fix to start-up routine so sbas can be enabled<\/span><\/font><\/div>
6) failsafe improvements (both throttle and battery) [Randy\/Craig\/John Arne Birkeland]<\/span><\/font><\/div>
    a) RTL will not trigger if your throttle is zero - reduces risk of accidentally invoking RTL if you switch off your receiver before disarming<\/span><\/font><\/div>
    b) failsafe triggered in unlikely case of a PPM encoder failure<\/span><\/font><\/div>
    c) bug fix to resolve motors momentarily reducing to zero after failsafe is triggered<\/span><\/font><\/div>
7) mpu6k filtering made configurable and default changed to 42hz for copters [Leonard\/Tridge]<\/span><\/font><\/div>
8) support ppm sum for transmitters with as few as 5 channels [Randy\/John Arne Birkeland]<\/span><\/font><\/div>
9) acro trainer - copter will return to be generally upright if you release the sticks in acro mode [Leonard]<\/span><\/font><\/div>
    ACRO_BAL_ROLL, ACRO_BAL_PITCH - controls rate at which roll returns to level<\/span><\/font><\/div>
    ACRO_TRAINER - 1 to enable the auto-bring-upright feature<\/span><\/font><\/div>
10) other changes and bug fixes:<\/span><\/font><\/div>
    a) allow >45 degrees when in stabilize mode by adding lines like below to APM_Config (compile time option only) [Jason]<\/span><\/font><\/div>
        #define MAX_INPUT_ROLL_ANGLE 6000     \/\/ 60 degrees<\/span><\/font><\/div>
        #define MAX_INPUT_PITCH_ANGLE 6000    \/\/ 60 degrees<\/span><\/font><\/div>
    b) bug fix to stop RTL from ever climbing to an unreasonable height (i.e. >80m) [Jason]<\/span><\/font><\/div>
    c) event and state logging [Jason]<\/span><\/font><\/div>
    d) allow cli to be used over telemetry link [Tridge]<\/span><\/font><\/div>
    e) bug fix to allow compass accumulate to run when we have spare cpu cycles [Randy]<\/span><\/font><\/div>
    f) bug fix so do_set_servo command works [Randy]<\/span><\/font><\/div>
    g) bug fix to PID controller's so they don't calculate crazy D term on the first call [Tridge]<\/span><\/font><\/div>
    h) bug fix to initialise navigation parameter to resolve twitch when entering some navigation modes [Jason]<\/span><\/font><\/div>
    i) performance improvement to copter leds - use DigitalFastWrite and DigitalFastRead instead of native arduino functions  [Randy]<\/span><\/font><\/div>
    j) removed unused stab_d from roll and pitch controller [Jason]<\/span><\/font><\/div>
    k) bug fix for guided mode not reaching target altitude if it reaches horizontal target first [Randy]<\/span><\/font><\/div>
    l) code clean-up, parameter documentation improvements [Randy\/Jason\/Rob\/others]<\/span><\/font><\/div>

<\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>
ArduCopter 2.8.1 22-Oct-2012<\/span><\/font><\/div>
Improvements over 2.8:<\/span><\/font><\/div>
- 430 bytes of RAM freed up to resolve APM1 level issue and reduce chance of memory corruption on both APM1 and APM2<\/span><\/font><\/div>

<\/font><\/div>
Improvements over 2.7.3:<\/span><\/font><\/div>
- Improved ACRO mode (Leonard Hall)<\/span><\/font><\/div>
- Improved stability patch to reduce \"climb-on-yaw\" problem (Leonard, Rob Lefebvre, Randy)<\/span><\/font><\/div>
- Rate controller targets moved to body frames (yaw control now works properly when copter is inverted) (Leonard\/Randy)<\/span><\/font><\/div>
- Less bouncy Stabilize yaw control (Leonard)<\/span><\/font><\/div>
- OpticalFlow sensor support for APM2.5 (Randy)<\/span><\/font><\/div>
- DMP works again by adding \"#define DMP_ENABLED ENABLED\" to APM_Config.h You can also log DMP vs DCM to the dataflash by adding \"#define SECONDARY_DMP_ENABLED ENABLED\" (Randy)<\/span><\/font><\/div>
- Watch dog added to shutdown motors if main loop feezes for 2 seconds (Randy)<\/span><\/font><\/div>
- Thrust curve added to linearize pwm->thrust. Removes deadzone found above 90% throttle in most ESC\/motors (Randy)<\/span><\/font><\/div>
- More timing improvements (main loop is now tied to MPU6000s interrupt) (Randy)<\/span><\/font><\/div>
- GPS NMEA bug fix (Alexey Kozin)<\/span><\/font><\/div>
- Logging improvements (log I terms, dump all settings at head of dataflash log) (Jason)<\/span><\/font><\/div>

<\/font><\/div>
Bug Fixes \/ Parameter changes:<\/span><\/font><\/div>
- fixed skipping of last waypoint (Jason)<\/span><\/font><\/div>
- resolved twitching when no GPS attached (Tridge)<\/span><\/font><\/div>
- fixed loss of altitude if alt hold is engaged before first GPS lock (Randy\/Jason)<\/span><\/font><\/div>
- moved Roll-Pitch I terms from Stabilize controllers to Rate controllers<\/span><\/font><\/div>
- TILT_COMPENSATION param tuned for TradHeli (Rob)<\/span><\/font><\/div>

<\/font><\/div>
Code Cleanup:<\/span><\/font><\/div>
- HAL changes for platform portability (Pat Hickey)<\/span><\/font><\/div>
- Removed INSTANT_PWM (Randy)<\/span><\/font><\/div>
------------------------------------------------------------------<\/span><\/font><\/div>\n","protected":false},"excerpt":{"rendered":"

APM:Copter Release Notes: —————————————————————— Copter 3.3.2 01-Dec-2015 \/ 3.3.2-rc2 18-Nov-2015 Changes from 3.3.2-rc1 1) Bug fix for desired climb rate initialisation that could lead to drop when entering AltHold, Loiter, PosHold 2) Fix to hard landings when WPNAV_SPEED_DN set high in RTL, Auto (resolved by using non-feedforward alt hold) 3) Reduce Bad AHRS by filtering […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[30],"tags":[],"class_list":["post-591","post","type-post","status-publish","format-standard","hentry","category-multi_copter_fc"],"_links":{"self":[{"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/591","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=591"}],"version-history":[{"count":0,"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=\/wp\/v2\/posts\/591\/revisions"}],"wp:attachment":[{"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=591"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=591"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hasu0707.duckdns.org\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=591"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}