Note: just as the release was going out an issue was found re support for the all Camera Gimbals on the APM1s (it doesn't work) and with 3 axis gimbals on the APM2 (2-axis works ok but not 3). If you're one of these people, please wait for 2.7.3 which will be out shortly.
UPDATE: 2.7.3 is now in the Mission Planner
Functional Improvements over 2.7.1:
- Fast waypoints (Jason) - if the turn angle between two waypoint the copter is less than 60 degrees it does not slow down
- Navigation improvements and logging including switching to filtered location for distance calculations (jason)
- Flip improvements - more aggressive and flexible flip code based on attitude instead of timing (Jason)
- Improved camera control - you can now control any axis (roll, tilt, pan) with any rc channel. it probably makes most sense that you will use 6 but others are possible too. Unfortunately these changes required we change the set-up procedure so the mission planner gimbal set-up screen needs to be modified again. Please refer to the AC_Camera wiki page for how to manually set-up the gimbal (Amilcar)
- Flybar acro mode for TradHeli (Robert)
- "Fast gains" - allows strong correction of attitude using accelerometers while the quad is stationary on the ground but relies more on gyros while flying (Tridge, Jason)
- Baro filtering improvements (Tridge)
- DMP timing fix (Randy) - the MPU6000's dmp unit was inadvertantly turned on and caused timing delays in the main loop- xbee bricking issue (Craig / Tridge)
- Dataflash fixes (Jason)
- Engine ticking - was a combination of roll/pitch rate D term being too high and the dmp timing fix above (Randy, Emile)
- Faster heading correction on start-up - resolves issue with simple mode getting incorrect heading if you took off very soon after start-up (Tridge)
- Increased maximum number parameters (Tridge)
- Formatting changes to code (Pat)
- Replaced "int" with "int16_t" everywhere (Randy)
As per usual PIDs are optimised for the 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props and are seeing bad flight behaviour in stabilize, start by turning down Rate Roll P in 25% steps.
There is still some question on whether the default Roll/Pitch Rate P (0.175) is high enough (it was 0.185 in 2.7.1) and also some people feel the Throttle Rate should be higher (currently 0.300 but some say 0.330 or even much higher would be better).
Please feel free to report issues you find in the discussion below and/or add them to the issues list.
Thanks and enjoy!