In this project, we are looking at balancing a Premium Bot on 1 leg using two approaches:

1.  Using the Foot Pressure sensing kit developed by HUV Robotics

This approach used the FSR sensors as pressure limit switches and thus had no knowledge of the actual orientation of the robot.  Once the bot got into its initial balance position, it read its 4 FSR sensors values and saved them as the goal values, and from then on it used the JOINT OFFSET commands to adjust the servos 11, 12 and 16 for Forward/Backward balancing and the servos 9, 10 and 18 for Right/Left balancing, i.e. trying to stay close to the initial FSR sensors values.  We found that it could accomodate rather steep inclines, however the changes in the angle of the incline had to be slower (see above video clips) than the 2nd approach described next. 

 

2.  Using the AX-S20 from Robotis.  The robot platform used was the Premium Humanoid A, and a similar control approach was used as in the FSR approach, except that we used the acceleration values along the X and Y axes in the control algorithm instead, and the same respective servos were manipulated to maintain balance.