Big Robot Party

As of this writing, there are four free, motile robots (and two robot arms) on Thingiverse, free to download and fabricate, all based on simple, standard technology.  Anyone can download the plans, and with access to either a 3D printer or a laser cutter, build them pretty cheaply.

At the moment, this is something of a curiosity for hobbyists.  Those of us who “know a place that’s got a machine” can get these designs made, but for most people, right now, the cost of any one of these designs is actually higher than a kit, since it would either take time (tracking down a trophy shop that will let them use the laser, for example) or money (it’s the first print on the MakerBot that’s expensive– they get a lot cheaper after that!) to get started.

But digital fabrication is spreading, and fast.  I wasn’t following the development, but I kind of doubt Bre’s statement that “your local trophy shop might have a laser cutter” would have been true even a few years ago.  With open source 3D printers beginning to mature, the hobby shops where one might buy robot kits may increasingly have a 3D printer behind the counter running at prices below fifteen dollars a pound.  (That would be about a 200% markup, incidentally, giving our hobby shop a healthy profit margin without models being anything like prohibitively expensive.)  Even a development as modest as this would mean that 3D printed robots would be cheap, plentiful, and with some friendly competition between robot creators, well-designed.

The additional components will get cheaper, too.  Many robot kits rely on gearmotors or servos for actuation.  These standardized, bundled packages include motors, tiny gears, and in the case of servos, electric control systems to maintain position.  The advantages of this pre-packaged solution are great: the tiny, precision gears provide excellent drive characteristics and exhibit only tiny amounts of “backlash,” and because they have such a broad set of uses, the market supports enough competition to keep the price fairly low.

(As I’ve said before, the primary arena where personal fabrication will defeat factory fabrication is the “long tail” of demand, where very few people need a specific item.)

However, the tradeoff that a 3D printer can bring to the gearbox arena is: low cost and high customization, in exchange for bulkier, heavier, more backlash-prone gears.  As improving technology puts the squeeze on these disadvantages, and as greater availability of 3D printing pushes the cost even lower, I think we’ll see creative commons gearboxes come into the hobby market in a very big way.

The cost break of a 3D printed gearbox is already pretty close to becoming fact.  A gearmotor kit from Tamiya generally costs about $10.  An equivalent 3D printed gearmotor might be put together for as little as $2, given that basic electric motors are so cheap.  Building this into a printable robot would create a very inexpensive machine indeed.  Using off-the-shelf electronics, I compute that a simple printed robot could cost as little as $10, at which point a hobbyist who might have built a single robot from a kit or custom-designed and built one might just download and digitally fabricate a dozen or more for comparable cost and have a robot swarm.  Many of the robotics experiments we see universities performing lately are with swarm robots.  3D printing just might let hobbyists start to do the same thing.

And that would be a very big robot party indeed.