Electro Tennis at the frog SXSWi opening party

For the past 14 years, the company I work for, frog, has been hosting the SXSW Interactive opening party. For the past three of those years I’ve played a role in it: brainstorming installation ideas, and building/coding really cool experiences for our thousands of attendees.

This year the core concept was turning digital experiences into analog ones, and vice versa. Additionally, one of the consistent themes of our party is to play with scale. So one of the experiences we set out to build was “Electro Tennis” (an electro-mechanical version of the classic Pong video game). But we decided to build it on an enormous scale — two 30′ x 25′ playing “courts”, each with a 12″ cube for a ball and 4′ x 3.5′ water tank for a paddle. In other words: giant.

Since I’m no good with welders, drill-presses, or making drive trains, my responsibility was to design the logic and code the software that controlled this experience. The first task was to work out how to make the X and Y carriages determine their bounds in the playing area so I could have the stepper-motors move appropriately. After much pondering of what types of switches were needed, how they would indicate where and when to stop, and so on, I settled on using reed switches and magnets for the core triggers. As long as the carriages were somewhere near their centers when calibration started, I could move in one direction until I hit a pair of magnets, stop, then move to the other end until those magnets were found, thus providing measurable areas to work in. Since we were using stepper-motors, I could simply tell the motors to move to one end numerical position, then the other, all night long.

My good buddy Jared Ficklin is in charge of both the logistics of the party and the making of experiences, and—as a skateboarding aficionado—built the truss to run on cool skateboard wheels riding on angle-iron rails. The design used was totally custom and the space between axle and rail was minimal. If I wanted to get sensors in there I needed something equally as custom to hold them.

And Thing-o-Matic #4967 Steps Up to the Plate

Through various design explorations over the past 8-9 months, I’ve honed my ability to look at a problem, take some measurements, open SketchUp and whip out an object that solves the problem first time. This time was no different.

This “thing” was composed of three sections: one to hold a 1″x1″ proto board, one to zip-tie to the axle, and one to adjust the distance between the two other parts. All three were held together with two small bolts and wing-nuts.

The ability to adjust the pieces both in distance and rotation was key to getting these pieces working as needed. They ended up being not quite parallel to the rail, and sitting just 1/4″ above.

The back of the thing needed space for solder joints to stick out (I’m not the cleanest of solderers) and wires to run out to the Phidgets motor controller board.

As I was printing the fourth and final set of axle holder parts, I looked around our rented workshop and realized that just as the drill-press, chop-saw, metal lathe, and MIG welder were the tools of my associates, my 3D printer was my tool, and it was just as important as all the other traditional ones. It very quickly went co-workers saying “oh neat” to just knowing that it was going to perform the task given to it, reliably, and accurately, and we’d end up with something wonderful.

Though we kept it separated from the other tools just so we wouldn’t get sawdust and metal shavings all over it, my Thing-o-Matic clearly earned a place on the workbench and became an invaluable addition to making the party a success.