Hand: open-source Robot Hand

Post by stefanka » Thu, Jul 17, 2025, 7:46 PM UTC

amelius wrote: post #19

imtringued wrote: post #11

Earlier quoted context omitted.

I think you're misunderstanding the essence of the problem. If you use tendons, you'll need a neural network in your control loop that can learn continuously so that it compensates rope stretch and changes in friction through wear and tear. A lot of problems in robotics reduce down to continual learning. Essentially all system identification tasks become obsolete the moment you have a self learning system and yet we…

You could add encoder patterns to the tendons, like stripes. And then use something like a mouse-sensor to track them. This is still much lighter than servos. Another idea is to use an external camera or two and to track the fingers with a deep learning model. But this can become messy if other objects are in view. And it might also introduce more control delay in the feedback loop than a simple sensor.

Post by eichin » Thu, Jul 17, 2025, 8:07 PM UTC

beAbU wrote: post #48

mft_ wrote: post #7

This looks like a nice, approachable robotic model of a human hand that can be printed and experimented with. But... is a human hand the best design for a robot to grip things with? Or could we surmise that the human hand evolved as a pretty good hand given the materials and senses that were available to evolve humans from , while in theory a totally different design might be optimal for gripping when constructed fro…

The human hand is arguably the best general purpose gripper of human-scale objects. Only took evolution a couple of hundred million years to figure it out. If you can limit the scope of things to be gripped, e.g. a sheet of paper, a baby chicken or a 100x100mm square steel girder then no doubt there is a better design out there.

Post by stefanka » Thu, Jul 17, 2025, 8:10 PM UTC

radlad wrote: post #61

0_____0 wrote: post #56

Earlier quoted context omitted.

People have been making end effectors using hobby servos for ages. These servomotors are designed for use in an RC aircraft, they're light, cheap, and expendable. Industrial needs care not about weight, care less about cost, and care a great deal about capability, repeatability, and reliability. This is a cool project for a hobbyist but it's not meant to be a serious industrial machine. Edit: what is with this thread…

I think the confusion stems from the fact that you're responding to a joke innuendo thread.

Post by stefanka » Thu, Jul 17, 2025, 8:18 PM UTC

Symmetry wrote: post #66

stefanka wrote: post #4

Earlier quoted context omitted.

Most tendons materials are elastic. That lead to create calibration problems and require proprioceptive sensors in the hand

In practice force sensing is more useful than proprioception in most cases, at least for grasping. Generally you won't the dimensions of an object you're attempting to grasp anywhere near as well as you would know the shape of the hand you're using so a certain amount of underactuated compliance makes the job a lot easier.

Post by bredren » Thu, Jul 17, 2025, 8:21 PM UTC

Brajeshwar wrote: post #32

Here is what I’m more keen on, rather than the human-like robots that we are all expecting. For instance, I would like a wall-mounted or floor-standing multi-arm robot that serves as a kitchen assistant. One can add or reduce arms as needed/desired. It is custom-equipped with a fire extinguisher, thermometer, and the usual must-haves for a kitchen. It will hold the cutlery, plates, and other items as needed. It will…