Hello, I know absolutely nothing about mechanics, I just bought an Arduino and was able to set it up to get a stepper motor spinning. I want to build a moving camera mount with it, then later a robot. But I'm having some very stupid problems I'm not sure how to best solve.
1) How do I physically connect the motor to other parts? I'm using a 28BYJ-48 5V Stepper Motor, it has this shaft that spins, but I don't know how to screw a plastic platform to the shaft. On every tutorial that I've seen, either it was a complete kit with motor + legs/wheels that already fit in it, or the gears to fit the motor were 3d printed. But I was wondering if maybe these things have a standard format so I can just buy some nuts or something on any hardware store that would let me screw it to something else? Is that how it works? So far I have just duct-taped it to other stuff, but I suppose that are better ways :S If I find an arbitrary motor on ebay, how to I search for some other parts to screw it to the rest of my machine?
2) From what I understand, the stepper motor offers no feedback to the Arduino about its current position, right? How do you guys deal with this? What if I need to know the position of the motor on my code? If I just store an estimate on a variable, that will be off when the system is turned off. I read somewhere people use "endstops" for this, I'm not sure how. Does that mean, that every time the whole thing boots up, you just try to move the stepper in direction of the endstop, when it stops, you now know it's at that position. Is this really the best way? This sounds like waaaay too much trouble for just getting the position of the motor.
3) When looking at datasheets of motors. What is the "speed ratio" and "reduction ratio"? Some robotics tutorials suggests I look for a motor with 120:1 ratio, but I have no idea what does that mean? Is that the same as "reduction ratio" or is it something else?