Driving two or three stepper motors?

i relatively new arduino , planning first real build. want make xy gantry similar 1

using stepper motors off ebay (which have yet order).

the purpose move electromagnet turn on , off (also controlled arduino) move metal pieces  above thin sheet of glass/plastic.

i have never worked stepper motors (or motors) on arduino before, , have done research them. want use bipolar stepper motors on unipolar ones more powerful per amount current.

but don't understand how arduino connects driver connects motors drive them. how driver fit in arduino-motor interface? know motors need lot more voltage arduino supplies (12-36volts depending on motor), driver used for?

i need example , explanation of how driver works arduino , bipolar stepper. want drive 2 stepper motors (and later 3 z axis in there)..

another question how powerul need be. don't have idea of how strong amount of torque don't know how powerful need be. far  currently looking @ some decently priced 71 oz-in holding torque stepper motors. how powerful 71 oz-in? instance if wanted move cart 5 lbs it, able quickly?

lastly, common libraries driving stepper motors? libraries depend on driver use? commonly used libraries , drivers?

thanks!

this pololu web page gives lot of useful information using a4988 stepper driver board. other "proper" stepper motor driver boards work in similar way. don't tempted use l298 stepper driver.

the a4988 can drive bipolar motors have max currents of 1.2 - 1.5 amps. stretching things use full claimed 2 amps.

you need choose stepper motor before choose driver board. stepper needs have enough torque application. stepper driver board needs able handle current required motor.

my guess yours lightweight requirement , these motors might suitable. work a4988. (i have no connection products except customer).

proper stepper drivers (like a4988) have ability limit maximum current in motor coils when supplied high voltage (up 35v a4988 - boards can go above 50v). high voltage enables motor give full torque @ higher speeds.

be aware if choose/need motor current requirement beyond capability of a4988 (or similar) find driver boards rise in price no longer hobby products.

...r

Arduino Forum > Using Arduino > Motors, Mechanics, and Power (Moderator: fabioc84) > Driving two or three stepper motors?

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