This week I made some changes to the Egg Bot and named it version 2 (even though it’s really a version 1.5 probably). I combined the servo and circuit board mounting into a single bracket, printed the new bracket, and installed the new bracket. The bracket seems to have improved stability by lowering the center-of-gravity. I refined the PID controller, reducing oscillations and departures following perturbations. Finally, I added a long-term planner that changes the set-point of the controller along a pre-programmed path. The planner smooths the transitions by a rate of 5 degrees per second to improve stability.
The goal of these roll transitions is to create space for a future, simple (knee-less) leg to swing in a 2-D version of the Egg Robot. I will continue to experiment with increasing the roll angle to find the limits of stability with the version 2 system. Then, further analysis can be done to determine parameters for future egg bots and whether a 2-D design is feasible.
Next steps for Version 3 of the 1-D robot:
- Shoes so I don’t have to use the silicone mat to keep the robot from sliding
- More complex PID controller
- Enclosures for the front and back to add personality to the robot
- Eyes
- Battery power?