At the suggestion of Rana and Koji, I have worked out some design parameters for a Stewart platform to be used as a vibration isolation device or as a platform for characterization of suspensions. I have made some initial guesses about the following design requirements:
From these assumptions, I have worked out:
The combination of high force, high speed, and ~micron travel limits seems to point to piezoelectric actuators. PI's model P-225.80 would meet the peak push-pull force requirement, but I have not yet determined if it would meet the bandwidth requirement. Apparently, typical piezoelectric actuators can exert a greater push force than pull force; wonder if one could use an actuator with a smaller force range than the P-225.80 if the actuator is biased by compression. (Is this what is meant by a "preloaded" actuator?)
I have attached a PDF explaining how I worked out the actuator force and platform dimensions. (I'll try to dice up this PDF and put the contents in the Wiki.) I also have a plant model in MATLAB with which I have been playing around with control schemes, but I don't think that this is ready to show yet.
Here are some tasks that still remain to be done for this preliminary case study:
I'd like to ask for input principally on:
Edit: I also added a Mathematica notebook with the inverse kinematics (mapping from platform state to leg lengths) of the platform.
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(* http://www.wolfram.com/nb *)
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