The hand uses 15 servo motors to articulate 5 fingers with 3 degrees of freedom each.  Each finger is treated as an open-chain manipulator.  The Product of Exponentials forward kinematics method was used to compute the location of each fingertip.  Finger trajectories and corresponding inverse kinematics were generated for each finger to keep the platform spinning.  A webcam watches the plate and checks if it gets too off-center.  If the plate is looking like it will fall,  trajectories will be planned to return the plate to the center position.

Once the webcam has detected that the plate is off-center by about 15 mm, the LED’s turn blue and the fingers stop moving.  The internal raspberry pi calculates which direction it needs to push the plate back to the middle and generates trajectories for each finger to accomplish this.  First, each finger moves to a neutral position, so the plate stays stable.  Next, all fingers simultaneously travel in the target direction by the amount of offset detected.  Finally, all fingers move back to where they were previously, and the spin cycle starts again.