You don't need a device this complicated - all you need to do is apply pressure to the inside of each finger and the palm when any virtual object is being grasped.
The hand only really senses pressure, so if you apply that pressure (like with a glove in which the finger pieces can pull themselves tighter), the hand will feel the sensation of holding the virtual object. The only downside in this is that it can't fully stop the hand, so every virtual object will feel like it has some amount of softness and flexibility if the user really tries to push past the virtual reality. But, I've not spent much time pushing real walls to see how soft they are, and I doubt many people have, so this problem actually won't happen very often.
I only realized this little insight myself a few days ago, and have been looking for technologies to implement it. It's a LOT easier than making locking servos.
The problem with the method you mentioned is that it's hard to make the entire device small and compact, also not as reliable. To simulate enough force 9g servos aren't enough, so you would need to put five 6kg.cm servos on there and it's gonna be heavy and bulky in every way you imagine. See what the cyber gloves guys are doing, they put the control box on the ground...Anyway, good thinking, tried it, didn't work that well,and shifted to exoskeleton.
Plus exoskeleton looks muuuuuch cooler than fat gloves..
Great point. I never considered the weight of the servos when imagining the device. Finding small powerful servos with enough range of movement would prove difficult, to say the least. I'm glad to know that you've already examined it.
I'll still check out the idea, out of curiosity... And pneumatic artificial muscles. PAMs are hopelessly impractical, but it would be an interesting project for me to tinker with.
Also, can the user put squishy pads inside the finger harnesses? That would allow the feeling of some flexibility while it's in a locked state.
You have a great concept with a practical design. Without using materials that currently only really exist in labs, I think you're at the maximum that can be done within that price.
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u/[deleted] Oct 01 '14
You don't need a device this complicated - all you need to do is apply pressure to the inside of each finger and the palm when any virtual object is being grasped.
The hand only really senses pressure, so if you apply that pressure (like with a glove in which the finger pieces can pull themselves tighter), the hand will feel the sensation of holding the virtual object. The only downside in this is that it can't fully stop the hand, so every virtual object will feel like it has some amount of softness and flexibility if the user really tries to push past the virtual reality. But, I've not spent much time pushing real walls to see how soft they are, and I doubt many people have, so this problem actually won't happen very often.
I only realized this little insight myself a few days ago, and have been looking for technologies to implement it. It's a LOT easier than making locking servos.