Custom Cams for Mechanical Laser Show

thingiverse

Custom Cams for Mechanical Laser Show -------------------------------------------------------- ### Background The [Mechanical Laser Show](https://www.thingiverse.com/thing:2383299) by AdditiveTech is a really cool device where you can place a laser pointer on top of two cams and project various patterns across a room or the sky! Accompanying the design is a great video which describes all of the math necessary to make it project any pattern. He also provides source code for a program to generate custom cams. I wanted to play with the math some and along the way I developed some OpenSCAD code which will generate custom cams. **Note: this is a work-in-progress -- I haven't test printed anything yet but hope to soon.** ### Details Click the "Open in Customizer" button beside the preview and you'll be taken to the customizer. From there, you can draw the pattern you would like to generate cams for, adjust a few parameters, and download custom cam plates. I didn't want to keep printing gears for different cams, so I modified the gears to be separate parts with a tab to index the cam faces properly. ### Limitations There are several limitations when using the customizer version, mainly due to the drawing canvas it uses. * The drawing canvas allows multiple detached paths to be drawn on it. Only one of these will be used to calculate the cams. * The drawing canvas does not allow a path to cross itself, even though the script itself does not care. ### Samples The cam plates attached here are samples generated with the script to show the letter M. The coordinates were derived from an SVG path. ### Additional Features If you download the OpenSCAD file, several additional features are available. * You can enter coordinate lists directly into the file for a more accurate representation of patterns. * The file is set up for animation which allows you to step through the rotation of the cam plates and watch the movement of the laser pointer throughout. With some massaging of different components, an animation like this can be produced: