The biped uses a custom MC68HC11A1FN based board. In addition are two "Mini SSC" Serial Servo Controller modules to do the servo PWM.

I used to use two single chip HC11's to control the Model Airplane Servos as slaves of the main HC11. Available here are the HC11 Assembly routines for controlling servos and the explaination.

Here's the report on this Biped thing. In PostScript (56k) and text (14k) and html (14k).

The Back

The In

It never quite worked, and was superseeded by other projects (See Computer Vision).

In the CMU Robotics club, I've started working on a new biped. A few benefits it will have that I learned from this robot are:

• The hip is key. My old hip had so much slack that it could be moved about 15 degrees before it gave any opposition. The new hip will be directly driven by the servos. The hip servos will also be 4 times stonger.
• The new skeleton will be lighter. We're making the robot out of plastic because it's light, easy to work and fairly cheap.