Triode
Well-Known Member
I'm trying to figure out the best way to offer controlled variable resistance to human muscular motion. I know that in exercise machines this is done with a motor, but that might not have the range of resistance I need, ranging from about 150 lbs, to almost none and it must switch quickly. This is for a medical device to diagnose muscular/nerve disorders.
Ideally, it should let them move as freely as if they are moving through air and in a moment switch to resist. The resistance could vary from a hard stop like a wall to a slight resistance, like they hit a movable object.
I can think of several ways:
-An air shock with a very large fast servo valve; expensive but very effective with almost no resistance when on and a high maximum
-A rack and pinion attached to a motor which can actively resist, or use coil shorting; cheap, but minimum resistance is probably not that low, and maximum is probably not that high, will resist fast movement more even in low resistance mode
-Electro magnetic clutch - very fast, medium expense, very low off resistance, poor precision in resistance when on
Since there are so many devices out there I thought I'd see what people know of, anything could work even if it's very expensive (if it works well enough) or low quality (if its cheap enough) so let me know what you've seen.
(as usual I will explain why I need to ask questions if I am qualified to be doing something this advanced, I make systems for researchers, so I make mechatronic tools but I don't always know all about whatever I'm doing)
Ideally, it should let them move as freely as if they are moving through air and in a moment switch to resist. The resistance could vary from a hard stop like a wall to a slight resistance, like they hit a movable object.
I can think of several ways:
-An air shock with a very large fast servo valve; expensive but very effective with almost no resistance when on and a high maximum
-A rack and pinion attached to a motor which can actively resist, or use coil shorting; cheap, but minimum resistance is probably not that low, and maximum is probably not that high, will resist fast movement more even in low resistance mode
-Electro magnetic clutch - very fast, medium expense, very low off resistance, poor precision in resistance when on
Since there are so many devices out there I thought I'd see what people know of, anything could work even if it's very expensive (if it works well enough) or low quality (if its cheap enough) so let me know what you've seen.
(as usual I will explain why I need to ask questions if I am qualified to be doing something this advanced, I make systems for researchers, so I make mechatronic tools but I don't always know all about whatever I'm doing)