i have a basic prototype of a base built for my robot but I’ve been having a small issue. the robot won’t drive straight properly. I am using an x drive but when i drive forward it veers to the right and rotates clockwise.
Standard problems:
Do all of your motors have the same internal gearing: torque, speed, or turbo?
Is there excess friction on the right side? With an x-drive it is important to make sure that your bearings line up straight. If one of the 45 degree angle gussets is attached a little crooked it can cause a lot of friction.
Are all of your motors working?
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*]By the way, are bullet lists on the forum broken, or am I doing something wrong?
*]I’ve never tried using them before now, and it doesn’t appear to be working. I don’t think I’ve ever seen anyone else use them, either.
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i tested it with motor encoders free spinning and it came across with less than 5% differential
So the problem gets worse when your motors are under load/robot is moving its own weight.
Best guess is problem with x-drive construction.
that does make a lot of sense and i thought the same. but there is almost no changes that i have made that have worked
This is a pretty standard thing with X-drives. The problem gets worse as your gearing gets faster and faster too. You need to do speed control (PID) on each motor. I believe ROBOTC has settings to simply turn speed control on.
thanks thats awesome! ill try that out.
Just know that programming can only fix this problem by slowing one side down, making your robot slower.
yeah thats a sacrifice i feel is worth it.
Post a photo so we can see what you have built. Don’t cut any corners on build quality otherwise you start off at a disadvantage.
Alright ill do that soon. Hopefully the community will be able to provide some insight
are you using holonomic or a actual x drive?
So you are posting on something from about 2 months ago and I am not sure what your exact question is.
An X drive is holonomic. The name X drive refers to the axles on the wheels or the torques of the motor and not the wheels themselves making the X shape.
Now that someone posted i realized that i had never replied. Thank you guys for your advice. I rebuilt my base to maximize space and made sure to include all of your suggestions. I think there was friction applied to one of the wheels and that was causing issues.