Caster wheel steering off robot.

[JourneyTronics]

Hello! I am currently facing some difficultly in making my robot move straight. I have actually successfully implemented encoder motors and PID settings to make the robot move straight however, the problem lies within the front caster wheel. The caster wheel was intended to act as a balance but now it's steering my robot. The robot is able to move front and back nicely however sometimes, the caster wheel would be angled and thus steering the entire robot off-course.

I have attached a photo of the wheels for you to better visualise my robot.

The robot has to be able to turn thus I cannot permanently straighten the wheel too.

One solution I found was using a compass however I am having a lot of difficulties getting my MPU9250 to work because I think the motors might be interfering with it.

How should I solve the problem? Any help is appreciated thank you!

[alto777]

Change out the caster, it looks way too big.

Lubricate the caster, the idea is it should align itself.

Rebalance the entire arrangement so the caster has the right load on it so it functions properly.

Until then, don’t try to fix it other ways.

HTH

a7

[JourneyTronics]

I see! Thank you for the speedy reply!

[Railroader]

That hard plastic wheel likely has a low friction coefficient regarding the floor. I would like to se a rubber surface That gives more friction and a better caster turning torque..

Do You have some old fashioned door carpet in rather soft material? They usually have a rubber antislip on the back side. (under side).Turn it up side down and test?