Brainwave is a low cost controller for Reprap 3D printers derived from the well

Brainwave is a low cost controller for Reprap 3D printers derived from the well known Sanguinololu. The primary design goal was lower cost, achieved by providing only the minimum required components for a single extruder printer. It can be used to drive a cartesian or delta style printer.

a project headed up by @Matthew_Wilson1

also available @ Metrix

I can get a sanguinololu kit for $50 on ebay, and 4 drivers for $10/ea, for a total of $90. $10 cheaper than this board, and the ability to replace the motor drivers if needed, as well as needed expansion for SD-printing This should really be ordered in a bulk unit to get the prices down. I do love the native-USB atmel chip used on it though. We really need to move away from the usb->serial chips.

I’ve been looking for something like this. 32x microstepping you say?

@Jason_Gullickson , the new pololu stepper driver boards have 1/32 microstepping

Crazy…I still need to learn more about what microstepping is, how it works and what the trade-offs are (right now I’m still at the “more is better” level of understanding :slight_smile:

Microstepping basically just slowly energizes the next coil in the stepper motor slowly, in steps. Generally “more is bettah” is right, but the drawback is that it’s less repeatable the higher that number goes. I think 1/32 microstepping is about as high as I’m willing to go.

So is it pulling the armature of the motor somewhere in-between full-stops, or something along those lines? I thought I had read there might be a decrease in torque when microstepping, or something like that?

Yeah, it’s as if you had a magnetic ball on a track, and 2 electromagnets on each end.

Power electromagnet on one end, the ball moves to the left. Power the other electromagnet and the ball moves to the right. That would be “full step”.

However, power the left magnet by half, and the right magnet by half, and the ball moves to the center. That’s half stepping.

Power the left by 25%, right by 75%, the ball would be about 1/4 the way down the track. That’s 1/4 stepping. And so on.

@ThantiK yes you could do that if you like, but you will in the end run about the same price. I still think my board is better :wink: Also, you can replace these drivers, and at a lower cost. All it requires is an x-acto knife and soldering iron. I intend to do a tutorial on it at some point.

Personally I really don’t like the driver modules for a variety of reasons: easy to install wrong, poor thermal performance and high cost.

I didn’t put an SD card on there because I personally don’t use one. Maybe I should try it. I was focused on lowering the total cost, so that part wasn’t included.

As for microstepping, 32x really is the limit. The use of a chopper drive really limits the resolution. Past 16x it doesn’t really help much other than to make the motion a little smoother and quieter.