221–230 of 258 posts
Please stop gluing 3 servos together and claiming you built a robot :D (servos motion is quite jerky, that is why they don't have a video showing off this "robot" operating)
Here are some videos of the robot moving: https://twitter.com/alexkoch_ai . The advantage of this robot arm design is that it's very lightweight. The XL330 motors are just 18g each. This makes it very suitable for teleoperation and robot learning.
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> " Arm wrestling a toddler " Like arm wrestling a brick wall; if you can push it over then you win, if you can't push it over then you lose - either way there's not much fun in it. And if it can beat the toddler it risks injuring them because neither of them really understand what's happening and what the risks are. The arm can't stop if the toddler says 'ow'. > " Handwriting notes for small jewelry brand? " Can be…
I like how this comment is clear, comprehensive, full of common sense, AND very likely to be completely outdated within a few generations (5 years?) of robotics + AI progress. I would also not discount how easy it is to sell people on additional cameras in their homes (including the bathroom) for the sake of convenience.
Hardware generations are typically closer to a decade than a year. Robotics is moving fast these days, but not that fast.
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I think about this regularly just don't have the time to pursue it: Couldn't you build your arm in Nvidia Omniverse by also adding feedback like a cheap hig resolution distance or angle detector and train an ml model to compensate it?
Making and animating a 3D graphics robot arm is trivial compared to building it in real life. So not so much Omniverse, you would want to use a proper simulator like gazebo. But beyond that, the kinematics as well as the force dynamics for controlling a serial manipulator are very well understood. So there aren't too many gains to be made by AI. It is difficult to implement in software due to some tricky situations a…
1 AI model per motor
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Yep. Interestingly, there has been a lot of recent work on models like RT-2 that might be capable of automating this for simple tasks. We might be at the point soon where that startup would have been viable!
AFAIK RT-2 doesn’t quite work outside of Googles micro-kitchen, where they collected about a 1000 hours of data.
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I think even more difficult than making it affordable will be making it reliable . OK-Robot says it has has a 1/3 failure rate, and takes ~20x as long as a human, at which point you might as well do the task yourself. I'd want the error rate and speed improved by an order of magnitude before I'd consider it anything other than a fun novelty.
AI technology is advancing at an exponential rate currently. The inquiry remains whether there's a limit to these technologies' potential.
Any idea how much weight this could hold? I’m wanting to manipulate a fan in my home gym with some eye tracking to get it to blow air on my face when I work out, but the fan is a few pounds. Alternatively: any hardware motor suggestions for such a project?
Most of these robots will use servo motors - that gives you dexterity but means that holding any position requires constant holding torque - which means limited payload and a lot of wasted power. For a heavy fan (don't forget the reaction force from moving air too), you'd be better off mounting it on a some sort of bearing and just using a motor to turn it. That way the motor isn't trying to fight gravity all the tim…
I believe it offers higher torque, better precision and ability to just stick to a position with relatively low/or no power due to gearing-side resistance.
I started working on a similarly sized arm. I've got a use-case, long time friends with a glass blower. I was thinking of using it to make faceted glass pendants. They've got a faceting machine but it is manually operated. The hard part is repeatability. You need tight tolerances and each joint in the arm adds inaccuracy the further you get from the base. If the base has 1mm of wiggle, the 20cm arm has 4mm wiggle at…
> The hard part is repeatability. You need tight tolerances and each joint in the arm adds inaccuracy the further you get from the base. If the base has 1mm of wiggle, the 20cm arm has 4mm wiggle at the end, and the arm beyond it has even more. Could this be solved by software instead of expensive hardware? Some idea I had a while ago was to build an arm out of cheap, "wobbly" components for the large-scale movements…
Yes.
Imagine a human putting a screw in a hole. You don't follow the "optimal" trajectory, you adapt it on the fly, even do several quick trials to do it.
Humans do it with a combination of vision, touch and planning.
Each of these is currently still a huge problem for AI, nowhere near human level.
Does anyone have any suggestions on something that's a little higher quality, i.e. more torque and larger, like the size of a UR5 but cheaper than $30k? There's always seems to be a gap between "robot arm with dynamixels/off the shelf servos" and "research-grade arms".
I’m very happy with the mechanical design for my four axis brushless motor powered robot arm with integrated 3D printed planetary gearboxes. I have some hope of picking the project back up and better documenting it, though the CAD files explain a lot. For the last few years I’ve been working on my own brushless motor controller design and I think this year I will have that stable enough to go back to working on this…
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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…
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."
I started working on a similarly sized arm. I've got a use-case, long time friends with a glass blower. I was thinking of using it to make faceted glass pendants. They've got a faceting machine but it is manually operated. The hard part is repeatability. You need tight tolerances and each joint in the arm adds inaccuracy the further you get from the base. If the base has 1mm of wiggle, the 20cm arm has 4mm wiggle at…
> The hard part is repeatability. You need tight tolerances and each joint in the arm adds inaccuracy the further you get from the base. If the base has 1mm of wiggle, the 20cm arm has 4mm wiggle at the end, and the arm beyond it has even more. Could this be solved by software instead of expensive hardware? Some idea I had a while ago was to build an arm out of cheap, "wobbly" components for the large-scale movements…