How do I achieve this? Grid of dowels powered by piston-like movement

I am completely new to this site and robotics, but I have experience in programming, and programming microcontrollers.

I would like to create a grid of "pixels", where each "pixel" is a metal or wooden dowel that is programmed to push in and out, like a piston.

I'm imagining a lot of pixels, maybe 40x40, where each could be quite small in diameter (1/4"). The Arduino would have control over the linear movement - up and down - of each pixel.

Could anyone point me in the right direction for accomplishing this?

• I'm glad you got an answer to this, but it's not clear from your question what you were struggling with in the first place.
– Ian
Jan 16, 2015 at 17:35
• – Ian
Jan 16, 2015 at 17:47

You may want to consider mastering the art of controlling an LED matrix first. Then, replace the LED's with some sort of actuator (motor, servo, or other mechanism) at each node of the matrix that performs the up and down motion that you seek.

It sounds simple, but there are other details to consider. Particularly, you'll probably need more power to drive the actuators than you would for LED's. This, of course, depends on the actuators that you choose.

There are probably more factors to consider beyond what i've mentioned (e.g. Cost, precision, sensor feedback, etc...), but the first step would best be learning how to control an LED matrix. I may even advise to look into using shift registers rather than multiplexing.

As for achieving vertical motion of the dowels with an actuator, there are a number of ways to do it. The easiest may be using a rack and pinion or a closed loop pulley with an actuator attached at one end.

• Thanks Paul. If I had a 40x40 matrix of dowels, how many actuators would be required? One per dowel seems expensive and unnecessary, but I wouldn't know how to independently control each one otherwise. Also, do you know a good resource for 1) learning more about these different systems, and 2) buying cheap supplies (like a rack and pinion setup that I could power from a DC motor / Arduino) Jan 13, 2015 at 5:28
• Sadly, in the setup i've described, you would need exactly 1,600 actuators :(. This assumes that every dowel must be controlled independently. The only way to reduce the number of actuators is to sacrifice independent control. If large groups of actuators are always activated together, you can create a single mechanism to raise only those dowels.
– Paul
Jan 13, 2015 at 5:36
• Also, just to give you a heads up, "shopping" questions are usually considered off-topic here on the robotics SE.
– Paul
Jan 13, 2015 at 5:41
• consider a linear actuator, pushing a pneumatic valve. 2 of them, one master on/off for the pneumatic fluid and 1,600 tubes, and you have what you want. It might be slow, but for more money, it can go faster. Jan 13, 2015 at 5:45
• @spiked3: how would the 1,600 tubes be controlled individually with only 2 actuators.
– Paul
Jan 13, 2015 at 5:51