Hi,
I have a Pololu 3Pi Plus and I’d like to add a caster or wheel to the front (so it doesn’t wobble around when stopping and stuff. Does Pololu sell attachments to add to the 3Pi Plus? Like a caster or wheel for the front of the robot? The robot comes with a caster on the back.
Hello.
We do not have any caster or wheels kits for the front of the 3pi+ like that.
Having a forth point of contact in the front would make the robot more susceptible to getting stuck in a position where the drive wheels are both lifted off the ground. So, to have a forth point of contact like that you would generally want some suspension or spring system (like the larger Romi robot chassis has). The batteries are offset to help keep it stable, and the skirt should prevent the board or sensors from hitting the ground if it stops abruptly enough to make it tilt forward, but you could try adding a little weight to the rear of the robot to see if that helps. For example, replacing the 1/2" plastic ball in the rear ball caster with a metal one might help.
If you’re only going to use the 3pi+ on hard flat surfaces, you might also consider adding something the front of the skirt that sits a little lower and prevents it from rocking quite as far (e.g. 3D print some small clip-on extensions).
Brandon
Yeah you hit the nail on the head. The robot moves around when stopping abruptly because of the lack of the front caster.
A metal caster could be nice. I’d like to increase the weight on the back of my robot. I’ve added a small wooden dowel to the front of the robot to stop it from rocking as much.
I also noticed that the 3Pi plus is very sensitive to weight distribution. I added some electronics to the top of that robot and due to the unbalanced weight distribution, my robot would not go straight anymore. It seems like this is a problem at lower speeds more. The robot won’t go straight if the weight is not distributed evenly.
I’ve build a custom chassis which I’ve 3d printed. Hopefully, this helps me distribute the weight better when adding more electronics to my robot
