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Power drill motor controllers


I am making an all terrain robot and I need I strong motor for the caterpillar tracks.

I was thinking of using power drill motors but I can't find a controller for drill motors ANYWERE.

Please help! thanks!

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erm i have not took any drills apart in my life yet so i dont really know but do you have any suggestions on any better dc motors?

I would measure the characteristics that Ossipee has mentioned and find a driver that fit those specs, or research how to make my own, or see if anyone else has made one and study their notes. If I still failed at that point, I would lie, cheat, and steal my way into a couple working motors with drivers.... ;)

Ok thanks!

What did you search for? I mean, what were the actual search terms you used. I think I can help you here, but first, I am curious as to did your searching thus far. How did you go about looking for a robot-style motor driver for your motors?

Also, did you find it easy to find other projects using drill motors? Again, just curious.

Now, on to your drills. I am a bit of an expert on drill motors and robots. I have done just about everything wrong at least once, and I know pretty much all the ins and outs of them. I can say that they are not the easiest thing to deal with and there may be better options out there. --I/we would need some more specifics about your particular project.

One more, have you ever built a robot before? Ever written code? Any electrical knowledge (volts/amps, etc)?


@CtC Yes I have made many but not with drill motors What I am making is an all terrain robot but I need strong motors for tracks so do you know of any good motors, tracks or motor controllers?

Great, you are familiar with this stuff. 

Well, just like folks said above, it simply comes down to figuring out what you will need in terms of what your drill motors draw and then getting a driver that will handle that amount of current.

It should be noted that your motors are going to draw INCREDIBLE amounts of power when stalled (up to 80 amps) and your driver needs to be able to deal with this so it does not fry itself (over-current protection and/or fuses).

In general, when drill motors are running, you can count on 10-20 amps per motor, but this will vary greatly depending on brand and quality of the drill.

Finally, drills run forward a LOT more efficiently than they run in reverse. Encoders will probably be needed to keep your two motors going straight.

Do you know what's the reason for some drillmotors going better forward? All the drillmotors+gears have been planetary gears, and i have seen no significant difference of speeds.

I have know a bot that has two motors from 14.4v drills. I source them from single 11.1 lipo. As my Oddbot H-bridge is under construction i use two basic L298N Motor controllers, one per motor, channels coupled. They get very hot but the bot performs surpsisingly well :) I haven't done very extreme testing yet. I plan forced air cooling with those cheap 12v brushless PC fans.

I know these motors aren't ideal but they have some pros. They are cheap or free (if somebodys drillbattery is dead he gives whole thing to you) They have much torque, actually they are too powerfull. I find the long axle, exposed after  chuck is removed, quite nice to mount the wheels.

It is not the gears that causes the difference in forward/ reverse performance, it the motor itself.

To be honest, you would have to talk to an EE to get specifics, but I have read and been told that it has to do with the direction of the windings, the "timing" of the comutator and brushes, etc. Again, I don't know specific-specifics...

That said, in practice, I can tell you there is a big difference (100 RPM at least and an amp or two difference in current draw). I have noticed this difference and can repeat it by simply swapping the motors from one side to the other, or driving in reverse. Put simply, drills are designed to drill (clockwise) and they do this best when they are indeed going clockwise.

WOW 80 amps that is TO much power erm is there any over strong dc motors that are just a few volts! 9-18v?

You might want to have some fun one afternoon and imagine all of the things your robot needs to be able to accomplish. For example, it sounds like you know you need some good mechanical power to drive all terrain, and drill motors are attractive because they provide lots of that torque. They also seem pretty electrically imprecise and inefficient at times because they aren't made to do all of the things a robot wants to do in order to beat that terrain.  I would wonder where I can pick up a better motor that might cost a bit more, but not require me to have a gigantic driver circuit for my motors. Heck, if you get the right stuff, it'll end up being more inexpensive because through your research, you'll find the right parts, instead of spending money and time on more trial and error than necessary.