Load cell instead of potentiometers?
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What do you think about using strain sensors instead of potentiometers? I think in such case stewart platform may work similar to IBM eraser mouse (aka trackpoint) only with 6 DOF.
Interesting concept! I toyed with several ideas, and the trouble with most of them was either price or construction.
Where would you obtain suitable strain gauges and how would you construct the device?
I think base and top, with necessary cutouts, could be made by PCBway or JLCPCB. To measure force, stick-on strain gauges, two per leg, in Half-bridge configuration II (based on https://www.transducertechniques.com/wheatstone-bridge.aspx) connected to 3 HX711 (2ch each, 80sps max) amplifiers. Both can be purchased from Ali or Amazon although I do not know how well they would work in this configuration. Aluminum standoffs from Aliexpress (https://www.aliexpress.us/item/3256803251548057.html) can be used for legs.
$12 for PCB (set of 10), $5 HX711,$5 legs, $10 strain gauges so much more than potentiometers. I suppose the advantages could be reaction time, longevity, precision (maybe) and smaller size.
EDIT: perhaps a better way would be to 3D print whole 6DOF rigid structure and affix strain gauges to it. Few such structures are mentioned in this old paper: https://www.collectionscanada.gc.ca/obj/s4/f2/dsk2/tape17/PQDD_0020/MQ37577.pdf
Yes the potential of being able to make such a device out of a single 3D print and some Sparkfun load cell amplifiers would make it very accessible. Indeed a challenge is not to make it more expensive than an actual 3dconexxion device.
I agree. I like the simplicity and low cost of potentiometers.