How to control this stepper motor?

Hi,

I got couple of these stepper motors but have no idea how to control them. Anyone got an idea what kind of signal am I supposed to send to them? I haven't found any specs about it.

Thanks, Jarkko

Look at the stepper library that comes with the IDE. It has wiring diagrams for both unipolar and bipolar motors. Yours looks to be bipolar.

It claims 20 ohm windings and 3 to 5V, which means only 150mA to 250mA, well within the means of most motor shields (you need 2 H-bridges, one for each winding). Probably the simplest option.

Thanks! I ordered L295D and SN754410NE so that should do it.

I recently acquired some similar motors. These are definitely bipolar 4 wire motors. Stick your ohmeter on the pins and you will quickly identify the 2 coils.

I'm constructing some tiny robots. What is your application?

I ordered L295D and SN754410NE so that should do it.

Perhaps so. But a simple bipolar h-bridge may yield weak stepping torque at low voltage. You may wish to examine true microstepping controllers such as: http://www.pololu.com/catalog/product/1182

I plan to compare both in near future and would be happy to send you results. I do feel slightly absurd using chips or breakout boards bigger that the motors :)

Joe

I'm trying to build a linear actuator matrix display and have ~1000 of these motors moving the pins. Torque is definitely a concern and I have to see how lightweight linear actuator mechanism I can build to put minimum stress on the motors. I built a proto yesterday with 2 different DC motors but another one didn't have enough torque to move the mechanism (reported 2.68g.cm), and while the other was ok it's too expensive for this project. It would be interesting to hear the results from your comparison!

I’m trying to build a linear actuator matrix display and have ~1000 of these motors moving the pins.

Wow! Really 1000?
Is this many little displays or one humongous mother of all displays?

No Way !...I was browsing the site for exactly the same project :astonished:.

I got myself some similar steppers, but with a bit of a lead screw already - http://www.ebay.com/itm/10pcs-With-a-small-screw-2-phase-4-wire-stepper-motor-micro-stepping-motor-6mm-/151065289378?ssPageName=ADME:L:OU:GB:3160

I am currently testing with some L9110 drivers, but I have issues with the size of the ICs and scaling up to a larger matrix. An the control with the arduino once you scale everything up...and that's even before mentioning the cost to go with 1000's of these..

..how big do you want your matrix to be?

All the best !

  • Flybythemoon

Do a search on the project description. It has been discussed before this year (and why such a project is hardly feasible). But building it (or trying) must be a lot of fun.

Thanks MAS3. This makes for interesting reading.

I went through all these trade-off a while back and down-selected the leadscrew approach...we'll see...

I am currently testing with some L9110 drivers

This driver is new to me. How do you drive the stepper with it?

Joe

[quote author=joe mcd link=topic=179053.msg1328286#msg1328286 date=1374699258] Wow! Really 1000? Is this many little displays or one humongous mother of all displays? [/quote] The plan is to have one ~30x40cm display. Regular pin point impression device has ~1000 pins, so that gives an idea of the resolution and what it's capable of representing.

Flybythemoon: No Way !...I was browsing the site for exactly the same project :astonished:.

I got myself some similar steppers, but with a bit of a lead screw already

Hah, that's great! :D It would be nice to hear your experiences as you work on it. Have you been able to implement the leadscrew based a linear actuator with those motors yet, and if so how fast linear motion were you able to achieve with it?

Oh and for inspiration I bumped to this post at Hack a Day the other day, which shows thousands of "pixels" linear actuator display in a bit bigger scale :D

20 of those little motors for $10? How do they make any money at that price?

20 of those little motors for $10? How do they make any money at that price?

They are available as surplus from Chinese vendors on ebay. Presumably leftovers from some large project.

These are Canon motors. Wouldn't surprise me if they were rejected (out of specs) zoom/focus motors for camera lenses. I guess complete batches might get rejected if a too large number of motors from that batch is not within specs. That doesn't mean these motors would be bad.