Let me give you guys a little history about my project. We are currently using an AP 2.6 hooked up to a 2x60 sabertooth module on a wheelchair. After some trial and error we have gotten the wheelchair to run in mixed mode similar to the way that it looks like you guys have that machine set up. Elevators and Ailerons on the right stick (I’m a NOOB so…) anyways…. we’ve got it functioning correctly when moving at speed however we are unable to get it to do a zero speed turn in steering mode…the bot is not responding. If we give it a little forward motion it turns fine but is unable to do so from a standstill. Any suggestions? Thanks in advance!
@corpsmanup1982,
Can you get it to zero speed turn when in the Manual Mode. If you cannot, then it won’t do it in the Steering Mode either.
I assume that you have the Sabertooth ESC setup as two independent motor controllers and SKID_STEER_OUT is 0 and SKID_STEER_IN is 1 assuming you are using an R/C transmitter/receiver to control the wheel chair.
Also, what are your SPEED2_THR P, I, and D, your Cruise_Speed, and Cruise_Throttle?
Regards,
TCIII ArduRover2 Developer
Thank you for the reply TCIII; I really appreciate it! We have gotten steering mode working correctly but now we are having problems with auto mode. Our problem is that it just seems to take off in a random direction every time. SOmetimes to the left, sometimes to the right, sometimes to the left. We re-calibrated the compass (not an easy task wince the bot weighs about 80 pounds 3 times and are still getting random actions when we place the bot in auto mode. She functions perfectly well on steering and manual modes. We have the roll set at 180 degrees because we are using the external ublox compass (sat lock averages at about 10 units.) I appreciate anything you can offer and thanks again for your reply; it was very helpful!
@corpsmanup1982,
How far apart are your waypoints?
Also, what is the value of your waypoint radius?
Suggestion:
Put the rover up on blocks so the wheels are free to run.
Program a waypoint that is either to the right or the left of the front of the rover and at least 10 feet away. Point the rover so that it will have to turn either right or left depending on where you placed the waypoint. Go to Auto Mode and see which way the wheels turn.
If you programmed a waypoint to the right of the front of the rover, the left wheel should turn faster than the right wheel indicating it is trying to turn to the right and go towards the waypoint. And vice versa with a waypoint that is to the left of the front of the rover.
If the rover’s wheels turn opposite of where the rover is supposed to go, then check the “reverse” box on the aileron bar in the Radio Calibration screen in the MP.
Regards,
TCIII ArduRover2 Developer
@TCIII Thank you again for your reply. Rather than setting it up on blocks we have a rather large yard to let it run around in…if there is a specific reason for mounting it up on blocks we will be more than happy to do it I just didn’t see the benefit of it. No matter which way we orient the bot it seems to choose a random direction and go that way. We went ahead and reversed the ailerons as you recommended just to try something new and we still had the same problem. We now have the rover working very well in manual and steering mode but autopilot is off by quite a bit. We tried recalibrating the compass a few times…every time we have had very good sat lock. Are there special concessions that need to be made in the PID settings or something like that for a rover that uses differential steering? Thanks in advance; we’re going to plug away at this until we get her working; thanks for all of your help!
@corpsmanup1982,
Save all of your parameters in the Full Parameters List using the save button and then provide them here in another post so that I can review them.
Regards,
TCIII ArduRover2 Developer
3 times and are still getting random actions when we place the bot in auto mode. She functions perfectly well on steering and manual modes. We have the roll set at 180 degrees because we are using the external ublox compass (sat lock averages at about 10 units.) I appreciate anything you can offer and thanks again for your reply; it was very helpful!