Our problem is when the autopilot is activated in any of the modes it just circles. It does not just circle at a GPS location it drifts and looses altitude as well. We use the Easy Star airframes with APM 1.4 and APM 2.0 with the xbees. Currently we are using the Mission Planner software (most current version) to do all mission planning and parameter updates. We have the configuration files from DIYdrones uploaded onto the APMs and we upload the way-point files like I said earlier with the Mission Planner software. The xbees tell us that the GPS is working and is locked, it also tells where the current heading is and the direction to the current way-point(the APM knows where it is at but it just will not go to where it needs to go...) It circles in all of the modes except we have not tested FBW-A&B at this time. Does anyone have an idea what our problem is? We have flown them in stock airframes and modified airframes with modified PID settings and default settings and I have no clue what is wrong.
can you confirm that the mission planner gives you the correct location? I read somewhere (also based on personal experience) that it's a good idea to reset APM once the GPS shows a lock. Otherwise you may falsely assume that it has one. Then are you sure that it actually (re)starts the mission and not just loiters around what it assumes is the home location? What happens when you switch to manual and "fly it away" for a while and then switch back to auto?
Sorry.. nothing but general debugging ideas.
Ok, when mission planner displays our location we use a google maps satellite view and it is exactly where we are standing so I would assume that the positions are lining up.
Yes when the GPS gets a lock for the first time initially I reset the APM. Along with that when the GPS gets a lock sometimes it is several seconds before the APM's blue light quits flashing, so I always make sure that both are solid before we fly and we also confirm that plane is oriented correctly on mission planner as well.
As far as the loiter around the home location, we have changed the loiter radiuses and we have moved the way-points far away(a mile) so they do not interfere with each other. When it circles it does not go anywhere it just circles where you turn the autopilot on. Also I would assume that in a mode such as stabilize that it should have nothing to do with way-points and home locations and it should just fly straight.
When you switch it to manual you regain full control(along with the throttle) and you fly it to a different location and turn it back to any autopilot mode then it circles where you turn it on at the new location. And like I mentioned in the problem statement it does not circle at a GPS location the wind blows it off course and it also looses altitude.
Thanks for the questions, please keep them coming. One thing I would like to mention, Initially when we connect the RC remotes for the first time we have to reverse the remote so that when you pull the stick back it goes up and when you push the stick left it turns left(they are reversed somewhere). This is a stock easy star airframe and I have not read where anyone else has had this problem. What we did to correct this is reverse the controls on the remote/radio and it corrected it. When you turn the autopilot on on the ground it changes the control surfaces correctly... When you point the plane up it tries to level it and when you turn the plane away from the way-point it turns it back towards it. I have no clue why it does not do this in the air though.
Hmm.. strange indeed. About your reversed channels: I had a similar experience with my easystar but I solved it by changing the settings in APM (via the dip switches or software don't remember). But you at that in FBW on ground the control surfaces move correctly so that's probably not the problem.
The next thing would probably be to look at the logs if you have any. At least there you could confirm that it is really in a mode where navigation should be handled by the AP.
Actually, since I'm not using the mission planner I think I can only be of limited help if this is some sort of MP/APM communication problem.
Ah yes, last idea: maybe your PID settings for navigation are too low? Check the wiki for the tuning hints maybe..
Good luck, Andre