I'm delighted to announce the release of ArduPlane 2.50 for your flying pleasure. This release has a lot of advances to some of the core ArduPlane code, and should be a big improvement for many people.
Perhaps the most important change in this release is the new DCM code that does acceleration correction based on the GPS. This improvement is based on work by Bill Premerlani which really advances the state of the art for attitude estimation on small microcontroller based autopilots. The improvement in attitude estimation is very noticable in flight, resulting in significantly more accurate control. Many thanks to Bill for his patience in working with Jon Challinger and myself to bring this improvement to ArduPlane.
Other significant improvements include:
There is one change in this release which may require some re-tuning. We were using the wrong value for time delta when using the PID controller for navigation roll. This has been fixed by making the PID library calculate the delta time internally, but it means that existing HDG2RLL_I and HDG2RLL_D values will be incorrect. I have fixed the defaults, but if you have your own settings for these, you will need to drop HDG2RLL_I by a factor of 5, and raise HDG2RLL_D by a factor of 5 to get the same result as for the previous release.
Thanks to everyone who has contributed to this release!
For the next release the plan is to concentrate on improved stabilisation and navigation controllers, based on the great work being done by Jon Challinger.
I noticed in the new AP_AHRS_DCM.cpp code that independent drift correction was introduced. Does this mean that yaw drift can be corrected without the use of compass or GPS?
I am really interested in finding a way of getting rid of the yaw drift without using the GPS or compass. The aircraft that I am building is unconventional and the yaw does not work as in standard airframes.
Looking forward to your answer.
To get an initial heading (yaw) you do need either a compass or a GPS. The DCM code can get an estimate of the yaw gyro drift without GPS or compass, although it will be quite inaccurate, as it won't take account of centripetal forces. It can't get the initial reference vector though, so the drift correction won't be useful.
How do you repeat a mission in the same flight or is that not possible. Today I was flying and had it do a shout auto mission. Then I flew around for a while and decided to execute the mission again but nothing happened. When I looked at the log it went to AUTO but the target waypoint was not one, it was the last point. Is it not possible to execute an AUTO mission more than once or is that a bug?
I also tried that and had same effect.. plane just came home. so I am anxious to hear the answer.
I do see that in the MP there is a command to "restart mission". so maybe if you have onboard telemetry setup you can just push that button. Maybe I will try that
you need to "restart mission" - else it just resumes, even if it's at the last wp.
Reset Mission? How do I do that from my transmitter?
there's currently no way to do that on transmitter.
That would be a very nice feature for future firmware updates. Most of the time I don’t have a computer at the flying field.
I upgraded to this from a older version (alot older) and I'm finding that on both my APM1 boards with Mediatek GPS, that the GPS gets a lock (solid blue led), but the mission planner is showing no GPS.
I've tried pressing the reset button on the IMU, it did not fix the problem.
I am using Arduplane 2.5 that is installed by Mission Planner, and I didn't compile my own build so I can't see whether MTK 1.6 was selected
Hai: maybe a bad GPS cable? I'd try another one...
Thanks Chris, but I've tried 2 APM 1s, 2 GPS, 2 cables.