The application is a heliostat. Initially I would build a tracker and I am confident that I can get the Uno to calculate the sun’s position. Once I have the system tracking I would modify it and add a mirror to make a heliostat. Cost is very important. Lack of electrical and mechanical knowledge and skills are the main obstacles.
There is a small commercial heliostat called a Sunflower that has a 0.5m2mirror and I would be aiming for two axis control of a mirror of at most 0.8m dia. Experiments with a wall mirror show this would be adequate. The mirror size and weight and wind effects will determine the motor size.
Stepper drivers typically have an Enable input to allow you to remove power from the stepper when it doesn’t need to hold position.
was really interesting as I had thought of using DC motors with a worm gear but that would require an encoder. Using a stepper with a worm gear would remove the need for an encoder and the worm gear means the power to the stepper could be turned off once in position? Servos seemed an option but they would need to be powerful enough to directly drive the mirror if I wanted 180o of movement.
Lets say I am going with DC motors or servos. I am still not sure about the wiring.
Is it correct that the power can be supplied directly to the motors and only control signals need to go via a shield ?
Attached is a drawing of how I imagine the power connections at the moment.
For fusing I was thinking of using small vehicle spade fuses but their minimum rating is 1A would this be suitable to protect the Uno? As well as controlling the motors the Uno will have 5 switches for manually driving the unit, say 4LEDs for diagnostics and 4-5 photo resistors to monitor light levels and delay tracking when light levels are not favourable.