The knee fixture,which held a cadaver knee, was made of two parts, the upper or femoral fixture and the lower or tibial fixture. The upper fixture was attached to the Adept robot, it held the femor, and it housed the five pneumatic cylinders. The robot created movement in 1degrees of freedom (DOF), flexion/extension and the five pneumatic cylinders created movement in the other 5 DOF. The tibial fixture held the tibia and fibula to the ground constraining motion in 1 DOF. A mircocontroller was used to control the force of each cylinder. DVRT's (Differential Variable Reluctance Transducers) were used to test the stresses on the ligaments in the knee.
The DVRT's were sutured onto the ACL, PCL, MCL, and LCL to measure ligament forces. The knee was then placed in the fixture and the robot and muscles were run to create the same motion as in the cutting of the ACL Deficiant Knee Research. The knee was run at 10, 25, 50, amd 100 percent loading of experimental values. The data was then compared to the musculoskeletal model for verification.