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!

erm i have not took any

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?

Generalize your needs.

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… :wink:

Ok thanks!
Ok thanks!

Out of curiosity…

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**
@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?

No worries

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.

WOW 80 amps that is TO much

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

**Requirements and parameters. **

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.

ok thanks every1!

ok thanks every1!

An alternative.

Windshield wiper motors come to mind as a possible alternative. Most likely they will be 12v, and, I doubt they will pull 80A at any time in their useful life. :slight_smile:

Difference of directions?

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 :slight_smile: 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.

Its not the gears

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.

Drill motors/Brushless motors

Drill motors work great for a robot so long as you don’t give it to much voltage/current. If you want your robot to do 80mph give it the full 18v and see what happens you will not be able to catch it. Harbor Freight has a 18v cordless drill for aroun $20 that has a good motor in it and you get a battery pack that can be taken apart an re-used as well as a charger. If you apply about 3.6 volts to the drill motor it will work at a low speed and will last forever. The other motor to consider it the brushless and a controller they are more foregiving and because they are brushless you have fewer items to wear out. Most of your hobby shops carry the brushless motors and have various types of gears you can get to attach to them. If you use two cordless drill motors you will need a controller to count the revolutions to make sure the tracking stays the same. Don’t try to do it without a controller with two motors as they will never track the same and you will be frustrated. You can have to identical DC motors built by the same company the same day and at the same time and they will never track the same. The next thing you can do depending on the weight of the robot is to use two servo motors and hack them for continous drive motors, while you will still need to track them you will get the torque to drive the unti so long as it doesnt weigh too much.

Taking a cordless drill apart is easy and only requires a few simple tools.

There are some great videos out on youtube that will help you if you decide to go this way.

Here ae the basics of taking one apart.

1) Open the chuck up all the way.

2) Down inside the chuck you will see a screw most likely a phillips or straight.

3) Remove screw, it is left handed so turn it clockwise to remove it.

4) Take a allen wrench of good size that will fit in the chuck and put it in the chuck and close it.

5) The chuck removes in the normal fashion.

6) Strike the allen wrench with a hammer and the chuck will spin loose.

7) Next is the clutch, remove the screws that attach the rotation part of the clutch and the spring.

8) to lock the clutch in continious movement put 8mm set screws into the holes where the bearings came out of.

There you have it and drive motor for a robot.

Relays anyone?

I have been meaning to weigh  in on this one for a while. I had the same delema a while ago when I started my all terrain bot, and I found the solution to be automotive 5 pin relays. they are cheap ($12 for 5 on ebay) and have LOTS of current handeling capibility (80 A) you can even get speed control if you reuse the MOSFETS in the drill motors. The only downside is you are going to have to do a bit of work with some driver electronics to get it to play well with an arduino or something like that (in my mind, WELL worth the savings you get) If you are interested, have a look at my build where I give a little more detail on the whole construction process. https://www.robotshop.com/letsmakerobots/node/34827