Right Stepper motor from Pololu

I have built the small object-avoiding robot at


I want to use stepper motor/larger wheels to gain more control. I have tried several bipolar and unipolar motors that I had laying around and they don’t have enough torque.
Can someone recommend a good, low cost, stepper that Pololu offers, or some other supplier.

Thanks.

Hello.

Thanks for sharing. I think using stepper motors for driver motors is tricky. I don’t have a specific reference design to point you to that shows you what can be done. Without something specific in mind, “enough torque” doesn’t mean much. You have to get some idea of the kind of weight your robot will have and of the kind of acceleration you need, and it’s all interrelated since the motors affect the weight and the minimum wheel radius you can use.

- Jan

You are right…I need to be more specific about what I want.
The basic question relates to the control of the motors. The bot that I built uses the Tamiya’s double gearbox driven by the l293 driver. As the bot roles forward, it will sway off the straight path. I want to be able to control the direction with no sway. DC motors are not as controllable as steppers. But, maybe there are better DC-gearbox motors…
I have not decided on how big or heavy this new bot would be but it will probably weight in around 6-9 lbs, mainly because of battery weight.

Anyway, I am open to suggestions!

Thanks again.

Steve

Unfortunately, I do not know of any stepper motors to recommend for a robot that big. By the way, going straight is generally difficult, and it will be difficult even if you find stepper motors with an appropriate torque/weight ratio.

- Jan

Hello.

Have you considered using DC motors with encoders?

- Ben