Let's Make Robots!


Navigate around via ultrasound















Recycle those hard drives!

The videos were taken with just a small handheld camera. No mic, no audio. Sorry. On the bench video, just checking out the basic mechanics. Even with the bolts, it still holds within its own space surprisingly well. For a short demo, set up a small playpen for junior with boxes and some very quick and ugly code. On my to-do list, definitely is some ramping and more sensors than just the one tunnel-vision sonar.

This crazy little diversion started while watching Dino Hackaweek tearing into some hard drives for an actuator to use in his Laser Oscillograph. It reminded me of just how much cool and useful parts that are in a hard drive. Googling hard drive robot returns only some very nice but static sculpture. So this is my small attempt at building something out of those parts.

While posting the draft, I did find RobotFreak's HD-Bot, using the case as a base. My apologies on the unintentional coincidence of naming. : )

My first victim is one of a pair of Maxtors that ran as a RAID0 until writes got too slow, and there's still plenty of spare parts left over.

For you Propellerheads, since the platters are only 3.75" in diameter, the standard 3x4" BOE and Proto boards are a bit too big. What's on the platters are Demo and Gadget Gangster boards. Sadly, GG has discontinued these little puppies.

Since I was after a circular base, the casing will be tossed. Unfortunately, the motor's coils were part of the casing and not a pop-out complete assembly like older drives. So much for progress, oh well. The platter's spindle cutout works nicely as a large central pass-thru. Some holes could be drilled out concentrically to lighten the platters, but they're already light enough for I need. The platter dumpers/collectors and Torx screws hold the training bolts, switch, sensor. Haven't found a use for the spindle, actuator or the magnets yet. Additional metal pieces not from the drive are the standoffs, bolts and flat plate cut for the ping sensor. Since most of the metal used here is aluminum, it's actually very light yet strong enough to take the occasional full-speed hit while running into table legs.

As the Pololu motors/case/encoders all natively use 2-56 hardware and 4-40 standoffs were the only viable option, the toughest part of the build was in squeezing 4-40 hardware thru them while still keeping everything solid and straight.

I'd like to both add an XBee and LCD to it and free up some pins. So also on the to-do list is build up with another deck and another Uno. I've never networked a master/slave AVR before, so we'll see how far I get there. : )

For scale, in front of the Stingray.





Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Hi are really a beginner at robotics and I have a question?

Do you have to have both Adafruit motor shield and gvs shield??

For the DC motors, yes, they do need a motor controller, but it doesn't need to be Adafruit's. For motors that small, there are plenty of others out there to choose from:


If you wanted to save yourself the money of a motor controller, you could use CR servos. They're not as fast as the DC motors, but easier to use.

The GVS shield just breaks out the pins from the micro making the connections easier and more secure. You don't need it, but it's still better than having loose wires flopping all over the place. You could also substitute any other prototyping shield and solder in your own headers:


There a lot of places that will explain the basics, take the time to check them all out. LMR has some Start Here bots. Some of the better shops like Adafruit/Parallax have tutorials on how to use whatever products/sensors you decide to use. There are robot clubs like DPRG and SRS with an enormous amount of information. And finally, a book I highly recommend you pick up is Gordon McComb's, Robot Builder's Bonanza (4th ed). It starts you at the beginning and goes all the way thru a lot more concepts you'll run into. Definitely worth the money.

Hope that helps.