I’ve got a career break coming up, and although it is for the purposes of getting back to my software projects, I have a few hardware projects I’d like to make, just for fun. A busman’s holiday, perhaps!
I wonder how people here are designing and creating hardware items based on one-off, low-cost pieces? For example I’ve seen laser-cutting of wood as something that can be done in a maker workshop, and from YouTube videos I’ve seen, these seem to cut with a good degree of accuracy (such that working gearboxes etc can be machined). There’s also 3D printing, though my impression of this is that the results are rather rough-and-ready.
My ideas, to help with answering the question, and for general interest, are as follows. They somewhat stem from my gentle-wake lighting post - I’d like to make a Raspberry Pi-based clock. My first thought is to see if a laser can be moved fast enough, using Persistence of Vision, to create the illusion of digits projected onto a wall. As it turns out, my research indicates that this has already been thought of! Professional light shows use something called a galvonometer, which uses perpendicular coils to move X and Y mirrors separately to deflect a laser beam, and they are capable of making up to 50,000 movements per second.
These devices are, unfortunately, expensive (£100-£200 and much upwards) so people sometimes make home-made versions out of servos or stepper motors. Since these are much slower, sometimes phosphorescent paper is used to lengthen the POV effect.
My other idea is a set of square “pixels” mounted in a frame, each of which rotate about their own (horizontal or vertical) axis. This will allow a robot arm capable of X-Y addressing to move to a pixel and turn it on or off. This could be done from the back of the device, so that the front shows a large 8x16 display. I would expect this would be made out of wood pieces.
(I did ponder a different approach to this, where pixels are loaded and emptied like Connect 4, but I suspect the resulting clatter every minute would not be ideal for a sleeping environment! Maybe there is a way this can be done quietly…)
The first idea would need a platform for the servos. It would be simpler to make, but various online reports suggest that non-galvo builds are susceptible to non-linear responses at the outer edges of the scan. This can produce image deformities, especially when attempting to run at high speeds. The second project is a lot more parts, but does not need as much prototyping, since the mechanics seem (to my untrained eye) pretty straightforward.
I seem to recall the JQ has (or had) maker facilities available for hire. Are they still active, and can anyone here recommend one? What design software is suitable, and is there a standard file format?