I am looking for any and all ideas on how to solve this problem!
I currently have a load application system that can apply forces and torques in all six degrees of freedom that is used to study knee kinematics. I need to apply torques to the knee joint. Currently, the system uses pneumatic rotary actuators that are controlled through a force controlled feedback loop. These actuators have too much friction and cannot apply low torques (~3 Nm) which is what I need. I am looking for any ideas or suggestions on other devices that could be used to produce rotary motion under force control.
Here are my design criteria:
1) Torque producing capability 2 Nm to 100 Nm. I am more focused on the low range but would like the system to be robust. I could settle with an upper range of 50 Nm.
2) Currently, I use force controlled feedback loop controller cards that produce an analog output of +/- 10 volts. I would like to continue using them if possible. Note: The controller cards have small wires (~ 22 gage) so they cannot handle a large current draw
3) If new controller system is required, I need a force control system, but it could function via a feedback loop
4) I have a space requirement of approximately 6 inches by 12 inches (width x length)
5) Only require about 100 degrees of rotation - I don't need 360 degrees.
Does anybody have any suggestions on equipment that can accomplish this? Please be specific.
