For this project, our team wanted to create an engaging and unconventional experience using a laser and phosphorescent material, while also giving each team member an opportunity to do interesting and applicable work towards his learning goals. There is a good amount of research on the effects of interaction between lasers and phosphorescent material, but there hasn’t been a lot of work towards the creation of a user-facing product. Our project is a phosphorescent sphere that displays images projected with a laser, the shape of which are either drawn by a user on a touchscreen or selected from several presets. In accordance with our personal learning goals, there is a heavy focus on the software and electrical subsystems, and we assigned each team member to a subsystem in which he wanted experience, rather than a task he already knew inside and out.
Subsystems and Minimum Viable Product
In a general sense, this project relies on user input from a touchscreen, which is used to direct a pan-tilt mechanism that controls the direction of the laser beam. Mechanically, we designed a geared pan-tilt that directs the beam from a stationary laser diode using a small mirror. Electrically, we integrated the necessary hardware to power and control the mechanical subsystem using the software subsystem. Computationally, we designed a software pipeline that takes user input and outputs motor controls for the pan-tilt mechanism.
The group priority was to project the desired image with only the expected spherical distortion. Accordingly, at the very least, we needed software that produces accurate instructions, a pan-tilt mechanism that operates somewhat smoothly and the ability to input an image directly from a file. Stretch goals included a fail-safe mechanism, a touch screen for live user input, and a more refined base and pan-tilt.
Budget breakdown below.