So, i want to control motors with arduino, but I don't have a clue on how to do it. It seems like by using this motor driver or this one i will be able to power this motor with an Arduino Mega.
If this won't work, let me know, if there is a simpler way of powering a motor with speed step and bidirectional control please let me know. Also, where can one buy more powerful motors than the one that i referenced above?
Thanks so much, if you need more any more info, just let me know.
The motor drivers you've linked to are for stepper motors, while the radioshack motor you've linked is a standard DC hobby motor. Pololu has some motor drivers that will easily handle the motor you've picked, but you will not have precise control of the rotation of the motor which I gather is what you need.
For that, you'll want to google "stepper motor". Steppers are motors with multiple sets of coils that you energize in sequence to step the rotor through a complete revolution, giving you fairly precise control down to the degree of rotation of a single step (or less - check out "microstepping")
These drivers only give you a convenient interface for controlling the motor. You still have to supply the driver with a power source for the motor. For example, you might power the motor driver with regulated 5vdc from your arduino but connect the unregulated 12 vdc from your battery pack straight to the motor power pins on also on the motor driver. The motor driver will then apply that 12 vdc to the appropriate terminals of the motor to cause it to do whatever you're commanding.
Thanks so much, if you need more any more info, just let me know
Yes, there is: What is it you are planning on doing with the motors?
You ask about where to get more powerful motors, but we need to know what you are planning on doing with said motors in order to have an idea of where to point you to get better motors. Realize that, depending on the application, more powerful motors can quickly translate into $$$; plus they tend to need heftier power supplies (which aren't cheap, either).
For instance, if you were planning on building a large CNC router table (say 4 foot by 8 foot), you could easily spend $1000.00 US just on the motors and control system, and not even touch the power supply question. Even a smaller CNC table (say desktop size) could still run quite a bit of money for the motors and controllers (though you should be able to keep things under $500.00 US), unless you are talking about something like the Cupcake CNC or Reprap machines, which use much smaller motors and such (and thus can get away with cheaper motors, controllers, and power supplies).
Then again, maybe you are building a plotter, or a small robot arm, or a 2 wheel desktop research platform, or...?
Two of the motors put together need to be able to power a tread, two treads put together will move a robot around
Alright; no problem - so, it is likely you don't need steppers; so you are probably looking at using DC motors, likely gear motors, unless you are looking at building a much larger robot (in which case you would likely go with 3-phase AC with an on-board controller system, or use an engine).
What size of a robot are you planning; also, why two motors per tread? I only ask this last question because with two motors (two gear motors especially), without any sort of clutching mechanism, can cause problems in the robot (stripped gears, jumped treads, large back EMF as a motor is driven like a generator by a faster motor).
I would stick to one motor per tread; incorporating clutching mechanisms won't be easy (especially if the robot is small) - it can be done, and the parts exist, but it isn't cheap (you could probably adapt some transmission parts used in 4WD R/C trucks).
With that said, a size is still needed; will this be a small desktop/carpet rover, or something larger? Indoor or outdoor (or both)? How long of a runtime, and how fast are you looking to run it?
Ultimately, though, you are going to want to investigate using h-bridges (either a controller or something you make - for your first time out, purchasing one would probably be best, although a simple small transistor and/or relay h-bridge isn't too hard to build). You might also look into converting an R/C tank over to Arduino control (some of the scale model ones, while pricey, can be easily controlled using a servo library).
I agree with zoomcat. You need gear boxes as well as motors and controllers. Continuos rotation servos are compact and easy to use. Great for small robots.
I have talked to my partner, we might switch to using wheels
anyway, it's gonna be small, like the size of an FTC robot at the largest. However, one of the designs we're considering is a robot that can climbt up a telephone pole using wheels. I don't know how much power that would require, but i don't want to invest too much in anything. Our goal right now is to get a motor running of arduino, no high and mighty goals yet. How powerful are continued rotation servos? And how does one go about converting an RC car to arduino control?
Runtime is probs 2/3 minutes tops, I don't know how fast
The two most popular controllers are the L293, and the L298. You can find data sheets online that will give more info, but the 293 is limited to about half an amp per "bridge," and the 298 is 2 amps per bridge.
I'd say get a L293, which can be had for three or four dollars. Follow the data sheet in setting it up, and try a motor on a small toy--my first was an erector set motor. For what you want, just trying to get one running, you don't need much, and the motor should be easy to salvage.
If you want fairly powerful motors, Pololu sell those too
As everyone has said, to get power, at low cost, you'll use a relatively high-speed DC motor, and a gearbox. (model servo's usually are DC motors and gearboxes + motor drive, and feedback)
We use something similar to these types:
What country are you in? We may be able to be a bit more precise if we knew.
The Tamiya gearboxes at Pololu are worth looking at.
Some of them have two motors, and a choice of gearbox ratio, so you can balance power with speed
Most of those use quite high current motors, which would be too much for an L293D (okay for an L298), but Pololu suggest these motors, which are higher voltage, and lower current, which should be okay
(I'm waiting for a dozen, but the ash cloud has delayed my delivery :()
