While I continue to work on my exosuit, I also need a plan b. Enter Butterfingers. Butterfingers is going to my personal robot that will pick things off the floor, hold cameras, and assist with everyday tasks.
I am not Tony Stark so my Butterfingers will just be a remote control arm on top of my old wheelchair. Vaguely in the shape of an excavator but with wheels instead of tracks and a grapple instead of a bucket. So far I have torn apart the wheelchair carcass and harvested it’s electric guts. My old wheelchair seat was fully actuated, it could recline, tilt-in-place, and both leg rests could move up and down. I only needed these actuators for the arm, but the rest of the electronics are for another project where I will connect my joystick to my pc. Here is the damage report:
Excuse the horrible cellphone image but the center contains the wheelchair base we are working with. While it pains me to see my high school chair bleeding on the floor like that, it is for it’s own good. It died on the same hill twice. The first time I welded the right side motor contacts together. The second time I don’t know what happened but it is the motor I have to work with. Taking the chair apart was a real treat seeing how it all worked. Removing the seat saved at least 150 pounds from the frame.
My original plan was to remove the actuators, which are just regular screw drives, and make my own brackets. However the tilt actuator is much stronger than anticipated. I was thinking 1/4 inch steel at most for the brackets. But the tilt actuator was attached with what appears to be 1/2 inch steel. I guess lifting 300 pounds all day is not trivial.
So the new plan is: Keep the original tilt mechanism for the Main Boom, use the recline actuator for Swing Boom, and a leg rest actuator for bucket control. Unfortunately my pc died and my new pc stole my entire project budget. But my pc is the most important tool so it must come first. Once the budget comes back, the first order of business will be powering the actuators and discovering their minimum and maximum lengths so I can model the geometry of the arm in Fusion 360.