The servos are completely rebuilt. The original control system is replaced my own control loop, implemented in Arduino Duemilanove boards. Also the default potentiometer is replaced by "AS 5043" encoders from "Austria Microsystems".
The trajectory is generated by a Pathplanner, which considers the Dynamics of the Structure. Maximum allowable torques in joints and maximum allowable forces in Rods are never exceeded. (The robot moves at maximum possible speed, constrained by max torque and max forces in rods).
This video explains why this type of path planning is superior:
Delta robots are not that difficult, and can be built by inexpensive components..