One of the most iconic R2 gadgets is his holographic projections, so I set myself the challenge of working out how I could create a similar experience with my build. It's taken a lot of design, iteration and prototyping, but I'm very excited to reveal footage of my R2 projecting holograms!
With the technology available I obviously can't produce three dimensional holograms, but with the use of a small format projector I can do the next best thing. I know there's other options like projecting a mist and projecting in that, but I need it be troop friendly for hospital visits and that doesn't really work so great in that environment. With some modifications and the creation of a custom mounting rig I was able to install it inside the dome. Now wherever there is a wall, R2 will be able to produce ‘holograms’ with the simple press of a button.
Essentially, I found a cheap remote-control projector which would fit inside my dome.
I then measured it with callipers and created a custom enclosure in Autodesk inventor. This enclosure then had a mounting ring modelled onto the front which allowed me to mount it directly to the Bob C Holo projector rings. Only chance I had to make to the ring was getting some longer bolts so that I could pass them through the 3D print and thread them into the rings to anchor it all.
I then CNC'd a Polycarbonate disc that sits inside the Holo projector which acts as a lens to protect from fingers. It also doesn't distort the projections like the semi spherical lens do.
The circular mounting area also has been modelled so it has internal geometry that then nests inside the hole to keep it stationary.
This helps ensure that the projector is all was straight on and doesn't obstruct the projections.
Theses first two photos below show the enclosure and how it connects to the holo mount rings
And this shows the enclosure complete with projector mounted inside the dome:
