PIC18F452 RISC controls all. Stepper positions are stored by PC. I assembled this stupid things hardware in my spare time and it took nearly one month. More than 80 pieces screws and nearly 100 nuts are used. Without software it was a metal heap.
Some explanations for beginners :
There are 4 stepper and 2 servos in this gadget. Stepper motors and driver ICs are removed from old printers.
Softwares: 18f452 mcu side software is based on Microchip’s “stepper motor example”. Pc side software is
just a conventional com port terminal program with some extras.
Before doing this I couldnt plan everything, learned while doing,
remembered some math and physics rules. Aluminium panels are used for skeleton. There are 4 step motors:
1st is at the bottom for circular movement, an old floppy disk driver mechanism holds and turns the whole arm.
2nd one used for lifting the arm,
3rd is at the centre and 4th one is for holding the grip mechanism. There are 2 servo motors. One of them is for circular movement (not used in the movie) and the second is for gripping. Grip mechanism is copied from internet. 2 gears are strengthening each stepper motor . This thing is very heavy and bulky but can be improved.
Stepper motors are not being driven simultaneously, this causes some delays. Every motor has to keep its own position while one of the other is rotating. Each step motor takes nearly 1 amp. current. Driving 4 motor at the same time needs 4×1 = 4 amp. current, this means very big power supply.
There must be a different way to perform the mechanical power to each movement point. Because every motor has to carry first its own body weight.
Duration : 0:9:41