I met two great guys at project night at sprout last night. Brandon (who makes this cool Arduino-compatible web-enabled Linux board) and Mitchell. I told them about the Exoskeleton project and they had some great thoughts:
- Mitchell suggested the idea of perhaps applying a spring-loading system for the joint actuation. That way force could be built up in the Spring by a motor while the leg was locked and could “spring” the leg forward in ambulation when needed. He mentioned that this is how some insects (e.g. fleas) store energy in their legs that allow them to generate large forces. That reminded me of the work that Yobotics had been doing with series elastic actuators.
- Mitchell also thought of the idea of an assisted gait perhaps relying on shuffling the foot some and in that regard to think of low-tech/no-tech ways of smoothing that process. His thought was the idea of perhaps having a slippery “sock” or material on the shoe for sliding and a tackier heal with treads for planting.
- Brandon thought of the idea of using a rope or pulley type mechanism that attaches to the ankle to provide actuation of the joints. We had fun trying this one out.
- Brandon also thought of the idea of a pin and hole system that would provide locking the joints in place to support the leg and body when standing. He extended that thought with the idea of a ratcheting sprocket system that would also have a pin drop in to lock the joint when desired. With the sprocket setup the pin could lock at different intervals for locking the leg at slightly different positions. I think that could definitely work with an electromagnetically-controller pin system. The idea of this would be as a replacement/aid for the PID motor locking system. It would be more surefire and would also use less energy than locking with PID servo control.
It was nice to fleshout these thoughts and to externalize some other challenges I’ve been having. It’s always a helpful thing when working on a project to get out of your own head or “vacuum” as my Dad calls it by talking things out with other people.