maybe something like this?
we do really know what were doing, were not just making it up, if you going to keep asking us all for advice please listen to it
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For now I will stick with something smaller for power supply & make sure everything remains safe for the motors. Already spent allot of money on what I already have so I don’t want to waste any more. I should have gone for the Aion Robotics you mentioned I think I’m close to spending £1,000 now so that would have been much easier, but at the same time starting from scratch has increased my knowledge much more than if I got something that worked right out the box
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Is there any tutorials on setting up a skid steer to work properly on auto missions? In manual mode it’s perfect but I’m having an issue with auto.
Until I get a better suited battery I’d like to understand what I need to do
you need to work back up from manual thru acro before you can get back to auto stuff, same process as you did for the first one
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Hey Pete, I did all the modes for testing like you suggested, acro, steering etc but in auto mode I’m still spinning around, sometimes it goes straight and sometimes it just spins.
Anyone who has the “basic tuning” section for skid steering it would be great to see a screenshot to compare
@dkemxr @David_Boulanger @count74 @ktrussell @TCIII @rmackay9
Edit: I have managed to get it to steer more straight than spinning but the rover wants to turn right or left over the course of getting to the end of a waypoint. It starts straight and then begins to drift out away from following a dead straight waypoint
Tuning is pretty unique for each vehicle type and the way your motors/wheels react to signals from the controller. In other words, someone whose vehicle is very sensitive to output changes will be tuned very differently than one that reacts slowly to outputs. If you can find someone with the exact configuration as you have, their parameters might be close to what you need. I am sure that my parameters would not help you at all. My rover is a full-size zero-turn mower and my actuators are kind of slow.
If it is driving well in steering and acro mode, it should work in auto.
In steering mode, if you keep the steering control straight ahead and just increase and decrease the throttle, does the rover stay straight? And can you gently make a turn and it turns nicely?
These guys have some impressive kits. The sky’s the limit but some of the wheeled units nicely equipped are <$1000
https://www.superdroidrobots.com/shop/category.aspx/robot-kits/195/
Number of sat’s and HDOP? What did you do to get it to stop “spinning around”?
That’s what I thought also when I’m steering and acro the vehicle performs well, it goes straight A’s desired & can turn accordingly to the signals from the transmitter. Not sure where it’s losing control in auto mode it should be spot on.
Maybe some other parameters that are involved with skid steering are not right & may only be coming into play in auto mode? Another member on here said the following to me:
Obviously some people have had no luck with auto when it comes to skid steering but manual, steering & acro seem to work just fine until the switch is flipped.
@David_Boulanger
Number of Sats usually above 30 with HDOP at 0.60 for each of the gps modules with GPS Level 4 for both (3DGPS), so I don’t think that’s the issue with the navigational capability but more of a tuning or parameter conflict via mission planner. One thing I tried was changing the MP servo settings from Skid Steer mode (CH1 Throttle Left & CH3 Throttle Right) to the normal traditional method (CH1 Steering & CH3 Throttle)
Haven’t tested it yet in auto but it worked the same way (tank style) in manual mode. This was something I read written by @TCIII:
When using a mixing ESC like the Sabertooth, you do not use the ArduRover2 skid steering mode. You need to just use the standard steering and throttle outputs and connect them to the Sabertooth corresponding inputs.
If steering and acro are behaving, it sounds like the Navigation L1 Controller is the issue. I had to work on this quite a bit. It is important to have the underlying PID tuning working pretty well first, which you have done if steering and acro modes are working. So, work with this: http://ardupilot.org/rover/docs/rover-tuning-navigation.html.
And it takes a lot of patience.
If you have a skid steer setup, meaning you don’t have Ackerman steering (like a real car), you can’t just change the CH1 and CH3 to traditional mode. If you physically have a skid steer setup, you have to tell ArduRover that is what you have.
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I can keep it as a skid steer setup on MP, this is the setup I had origionally on MP & to be honest it worked. I just thought I’d make a change to see if there are any improvements.
Yes the L1 controller in basic tuning is definitely a big factor in successful movement in auto missions. I will try this and tweak it in small increments & see what happens.
Another thing that I found strange is that in the Basic Tuning Page, Steering Rate box the rover works well as follows;
P 0.0
I 0.0
D 0.0
IMAX 0.0
FF (Feed Forward) 4.0
All the the settings are mostly on 0.0. When I change any to as low as 0.1 the rover starts shaking on the spot. The only setting with a value it FF. doesn’t seem right but it works when I’m in steering or acro mode
Right now in auto mode when I flip the auto switch it sometimes drives straight towards waypoint 1 then begins to drift mostly to the left.
Then sometimes I flip auto and instantly it begins to drift left. Rather odd
I do not understand how your machine can work in anything other than manual with those steering parameters! Wierd, indeed.
Those parameters will not work.
FF is just a portion of the steering input (from the user or the navigation controller)
added to the PID output, so the PID does not have to work the whole control path.
Without P there is no correction on any error introduced into the control loop. You will notice this if you pick up the rover in acro mode and yaw it left and right by hand. The wheels will not move to correct the unwanted yaw movement.
Add a little bit of “P” and you will see the wheels react.
I usually do not use “I” or “D” with my skid steering rovers. Ardurover handles the PID calculation different to Arducopter. With Arducopter, all the PID loops start when the throttle is raised, while Ardurover calculates the PIDs also in a standstill. This causes the I term to calculate on small sensor errors and the rover starts to creep after a while.
If you are not careful with “D”, it can cause higher current consumption, vibrations, or mechanical failure, because of rapid throttle changes.
You can also adjust the PID in steps of 0.01 in the full parameter list. Missionplanners Basic Tuning screen handles the inputs a bit weird. It tries to round your inputs, but the full parameter list shows the actual entry.
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It should work very well in auto. P and I of 0 is most likely your problem. I use skid steering sometimes and it works just fine
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Thank you for both of your replies. I didn’t know you could add the inputs for PID in 0.01 increments so I will start with 0.01 & work my way up. Also completely forgot about picking up the rover & yawing left & right to watch for correction changes by the rover.
I will begin testing when I get a chance & report back with some good news hopefully. Thank you both very much🙏🏼
@ArduNoob- Obviously some people have had no luck with auto when it comes to skid steering but manual, steering & acro seem to work just fine until the switch is flipped.
Come on Mus there is nothing obvious about this. This is simply someone giving up on doing the work to get their vehicle running.There is no merit in that reply.
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Guys, Steering and Acro are still using the PID parameters to control the outputs with the RC inputs being the “command” that the controller should try to achieve, right?
If so, then Mus must not actually have tested in those modes because as we said with parameters set to 0, it would not correct in any way??? Mus, is it possible you are only in manual when you are testing?
You should be able to follow the tutorials on tuning and tune initially in the Steering mode. Only try Auto after you have steering working, at least to some degree. Then you can tweak the final tuning in Auto. That is at least what worked for me.
Hey Kenny, the rover was definitely in steering & acro when I tried it out. Not sure how it worked & when you go into failsafe tab you can see the mode that it’s on when you switch it. Also if it doesn’t switch on the HUD it says “failed to change flight mode” so I know it was working.
I’m going to edit the PID with 0.01 increments and also work with L1 to see what happens. I’m sure it’ll be ok
