Hey there.
I'm working on a project where I have to design the electronics section of a stage threadmill. It should be controlled via DMX512, so it can be tweaked along with the other stage & lightning equipment. Requirments are 500kgs, ~10m length. We've been guestimating the motors around 3kw to cope with everything and still have some headroom. The design has 2 motors, one on each end, with interconnecting elements.
1.One of problems is maintaining them both at constant speed. I am thinking of optical encoders to balance it. Any better method of reading speed?
2. I want some advice on how to design the power stage.
If we go on AC motors (which seems the obvious choice), it will be hell, at minimum. 3kW variable frequency sinewave sounds like a lot of heatsinking.
If we choose DC motors, all that power needs to be rectified (or maybe a SMPS comes handy here, do they make them at that power?), and then it's a matter of simply varying pulse widths.
Any other choice of motors? How would the design of its respective power stage would end up? What about ac/dc motors? Any improvments?
3. DMX - tbh, i never worked with it before. Standard doesn't seem to be open, although I found a few documents detailing various aspects. Does anyone know some software which can turn the parallel port or serial port in a DMX controller? Where can I get some standards?
Thanks a lot!
