The Cartesian Hand: In-Hand Manipulation with All-Linear Fingers
38 points by AareyBaba 2 days ago | 8 comments
chuckledog 2 hours ago
Reminds me a bit of the TARS robot from Interstellar. It was portrayed as a highly capable robot with limited articulation. (CASE too) https://interstellarfilm.fandom.com/wiki/Robot
replyoctoberfranklin 4 hours ago
One of the challenging parts of imitating human hands is that our hands sense through the same surface which deforms as we bend our fingers. We don't have good robotic devices that can do that.
replyThis sidesteps the problem: the surface that contacts the object is flat and never bends, so you can apply a huge variety of very detailed grid sensors to it.
The "rolling between the fingers" trick is ultimately what eliminates the need for deformation.
Also, where are the motors? Inside the gripper, or at the other end of cables?
I'm very impressed with this.
Re: chopsticks, oh but it can! It can roll one chopstick between one pair of grippers. Do that while holding the tip against a fixed object and you'll tilt the chopstick. Once you get the tips touching, it can use them.
The motors are inside those chonky things just outside the fingertips. I'm guessing hobby servos, which are tiny cheap and strong.
The balancing there comes from the wrist joint, not the fingers. Obviously this device is supposed to be mounted on a wrist joint that can rotate (pitch+yaw). Wrist joints are pretty well-understood these days.
Rounded handle I don't see the problem unless the hole is too small for one of the fingers.
And the bowl has a radius that make orthogonal grip impractical.