Heavy Duty Sperical Parallel Manipulator

thingiverse

This is still very much a work in progress, with a long way to go towards completion. The goal is to be able to move substantial weight - think DSLR and lens. To that end, the axles are equipped with bearings (20-37-9mm) with M8 bolt/threaded bar through the center to hold it together. The worm gears were chosen because the motors could be switched off and the device would still hold its position. The worms gear is held on the motor shafts with some M3 bolts and nut. Bolts that hold the arms together and platform are M5, with more M3 bolts holding each of the motors in place. You will need supports for the gears, arm hubs, and the base, although the base only needs to support the nut recess on the bottom. Other print settings will depend on what you want it to do. At the moment, everything is printed in black or white with 3 shells and 50% infill. I found that the movement could be a little jerky until I filed the surfaces of the worm gears and cogs smooth. Applying grease helped this even further. The bearings are a tight fit into the recess, but you may need to open the holes out by hand. I also found that the center shaft was a tight fit, so I had to remove material from it, but I'm not sure if that was because my printer was protesting about printing things. At the moment, I am using an Arduino Uno board with a CNC shield and 3x A4988 stepper drivers. I don't need to use GRBL, so here are some pin numbers for you: Enable all motors - pin 8. Direction Z: 7, X: 5, Y: 6. Step Z: 4, X: 2, Y: 3. Where is this going from here? The arms need to be beefed up, and I may well use some small bearings on the joints to help with any friction issues that arise. Possible applications of some sensor to make it level are also being considered. I have added an updated worm gear as well as arms. These arms are designed to accept 5x10x4mm bearings. There is a slide-in bearing retainer and bearing spacer for them. At this time, I have decided to stop any more work on this project due to not being able to alleviate movement in the joints. To get rid of this, all the bearings would have to be press-fitted onto the shafts that fit together. Also, the kinematics of this are a massive headache. As a result, I am going to focus on different mechanisms.