Scanning Surfboards Using a Computer Mouse

I’ve never been on a surfboard myself—that would be like begging to get skewered by a narwhal—so my knowledge on the dynamics of riding is all secondary. Those dynamics are highly dependent on the size, shape, and contours of the surfboard. Some surfboards are designed to be nimble and easy to turn, while others are designed for stability and speed. People who make surfboards experiment with shapes to find the best design. Ryan Schenk fabricates surfboards by hand, and needed a way to reproduce the contours of boards that ride well. To digitize those complex surfaces, Schenk built the inexpensive Scanbot 69420 using a simple computer mouse.

When Schenk creates a new surfboard, he carves and sands the contours by hand. He then takes the board out for a spin to see how it handles. If it feels good, he wants to be able to recreate the design. To do that, he needed a way to measure the contours. Instead of relying on expensive equipment like a 3D scanner, Schenk built his own mechanical curve “digitizer” out of an old computer mouse and a cheap digital dial indicator gauge from Harbor Freight. That gauge isn’t precise enough for conventional machining, but it is more than good enough for shaping surfboards.

That gauge is used to measure the height (Z axis) of the surfboard’s surface at any given point. The computer mouse is used to monitor the X axis position of those points. By moving the mouse, with the gauge attached, across a flat plane, Schenk can get a precise 2D “map” of the board. Scanning multiple lines along the Y axis results in a 3D height map. This did require some modification of the mouse and gauge. All of the mouse’s electronics were replaced with a µduino mini Arduino. The gauge happens to have a serial debug port, which can be used to monitor the height that it is currently measuring. The X and Z values are logged with a Node.js script, and are then rendered as a vector drawing. Now Schenk can easily scan and reproduce his best surfboard designs.