Unfortunately, my hardware assembly skills are next to zero. Is there any chance to get a pre-assembled prototype? I’d happily pay for the BOM and blog about Adrian’s experience with this.
The downside to a motorized display is the cost. Each motor is roughly $1.50 USD. When you include all the other stuff (electronics, 3D printed parts, etc.), it's at about $2/pin. A relatively small 10x20 display (minimum size for a Tetris board, for example) would cost $400 USD just in raw cost.
At retail, that 10x20 board would likely be around $1000 USD. Arguably this is why no one has mass-produced something like this yet. A larger display would just be too expensive to be practical for most people.
BUT!... Like I said, the feedback would valuable to me so am happy to make one for free. Classic warnings apply: it's still a prototype, so supervised play would definitely be required.
I do hope that research goes into a more cost effective non-mechanical bump map. In a hybrid display, this would be useful for sighted persons too. For example having tactile feedback from the screen on the car's console would let the driver keep eyes on the road. And then of course let's remember that blindness isn't just seeing darkness, plenty of blind persons have enough usable vision that a hybrid display could be quite useful for them too. I know that's all pie in the sky, but the sad fact is the best accessibility technology is built on building blocks that are useful to sighted people. The iPhone's literally life-changing VoiceOver technology is the most striking example that I'm familiar with. It's a shame Apple ditched the haptic technology on their displays.
Linear actuators with DC gearmotors have more fine-grained positional control vs plain solenoids. But that could be fixed if I use a tubular linear actuator design that looks like a solenoid. [1]
But at this point it's more important to get something/anything to a V1 and start getting real world feedback.