There is a reason there is no standard hobbyist-grade robotic arm.
People think they can build their own robotic arms for leas than a "real" robotic arm costs, but the do not account for wobble or repeatability.
With all due respect to the person who posted a design for a robotic arm made with RC servos on HN, I would like measurements of the repeatability. Have it draw the same pattern on a piece of paper every day for a week. Show me how closely the 7 lines overlap. I doubt that it can draw such a thing; it will tear the paper or get jammed without the strength to tear the paper.
Source: I've been building hobbyist robots since the 1980's, researched robots in the 1990's including a masters thesis, and teaching robotics for most of the last decade.
The hobbyist market is pretty forgiving of repeatability issues. The Ender 3 introduced many people (myself included) to the 3D printing world and is known for its problems.
Horses for courses. Nobody's going be trying to weld car chassis with one of these, true, but also a hobbyist wouldn't want some ABB or FANUC or whatever industrial arm in their house where it could kill someone. These small light duty less-rigid robot arms are fine for what IMO is the really exciting stuff like modern machine learning control research, which is exactly what this guy's doing with them.
^Modifying cheap servos so that a robot arm can repeatedly insert a pencil lead. It's a lot of work though.
Most interesting application though fall out of the scope of old-fashioned robotic arms, i.e. when you need to sense the real world in a non controlled context. For instance to develop a robot that can trim wilted flowers, you'll need to measure the real world, and as soon as you do that, you can just sense your robot arm too, no need for fancy, ultra-precise actuators.
Do you really need the $6,129.95 & $3,549.95 robot arms for the kind of application described ? I doubt it. I'm not a robotician, and would love some feeback on this idea.
Is this not something that can be addressed with cameras and (maybe) learnt approaches now? You don't need blind repeatability if you've got good visual monitoring to close the control loop, you just (just!) need good accuracy and low latency from video to motor control.
Why not just throw a SteamVR/Vive laser tracker onto the end of the arm and use that to close the loop? They claim sub-mm precision at room-sized distances, so it should be even better if you had it basically mounted on the base. If you wanted to get fancier you could build it into the end effector w/ one of these?
https://tundra-labs.com/products/tl448k6d-vr-system-in-packa...
Why are you so negative towards this? It's just an Open source project... who cares how good it is. It's a great way to learn, and play, and experiment.
That post is in the category „all knew it was impsossible until some stupid with no idea made it“
That somebody was 4 decades failing, does not mean that at some point it won‘t be possible. In the last 4 decades the prices have lowered and the quality is much better in the RC world, if you know where to buy.
> Why are you so negative towards this? It's just an Open source project... who cares how good it is. It's a great way to learn, and play, and experiment.
I did not mean to criticize a hobbyist project for existing.
I meant to say "There is a reason there is no standard hobbyist-grade robotic arm."
People think they can build their own robotic arms for leas than a "real" robotic arm costs, but the do not account for wobble or repeatability.
With all due respect to the person who posted a design for a robotic arm made with RC servos on HN, I would like measurements of the repeatability. Have it draw the same pattern on a piece of paper every day for a week. Show me how closely the 7 lines overlap. I doubt that it can draw such a thing; it will tear the paper or get jammed without the strength to tear the paper.
Source: I've been building hobbyist robots since the 1980's, researched robots in the 1990's including a masters thesis, and teaching robotics for most of the last decade.