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Low Cost Robot Arm

github.com

121–130 of 258 posts

Re: Low Cost Robot Arm

#121

The geek in me is drooling, but are there any practical home uses others have found for robotic arms? Hacking is always more fun with a good project

An impractical use would be to have a few of them replace monitor arms in a multi monitor setup. You could then rapidly switch between a few configurations. Also, have one to stir pasta in the kitchen.

At 1.4 Nm torque, the main motors would likely struggle manipulating a 0.5 kg item, they aren't strong enough to hold a monitor.

Re: Low Cost Robot Arm

#122

I'm surprised (or perhaps very unaware) that there doesn't seem to exist a company yet that mass produces cheap, high quality, reasonably standardized robot arms. So many things like 3D printers or CNC machines have entered the consumer/amateur level price realm, but this seems to be something still largely unexplored. Seems to have Arduino/Raspberry Pi scale potential, but I haven't heard of a name/ecosystem that po…

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…

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.

Re: Low Cost Robot Arm

#123

I'm surprised (or perhaps very unaware) that there doesn't seem to exist a company yet that mass produces cheap, high quality, reasonably standardized robot arms. So many things like 3D printers or CNC machines have entered the consumer/amateur level price realm, but this seems to be something still largely unexplored. Seems to have Arduino/Raspberry Pi scale potential, but I haven't heard of a name/ecosystem that po…

There have been a few around, but the limiting factor (as you can see from the BOM in the link) is the cost of the actuators. They get expensive fast.

I was looking at electroactive polymers (EAPs) and I could not find a single company with consumer pricing...

I wish there was more visibility here without requiring a PhD.

Re: Low Cost Robot Arm

#124

Earlier quoted context omitted.

An impractical use would be to have a few of them replace monitor arms in a multi monitor setup. You could then rapidly switch between a few configurations. Also, have one to stir pasta in the kitchen.

At 1.4 Nm torque, the main motors would likely struggle manipulating a 0.5 kg item, they aren't strong enough to hold a monitor.

Sacrifice speed and add a gearbox?

Re: Low Cost Robot Arm

#125

I'm surprised (or perhaps very unaware) that there doesn't seem to exist a company yet that mass produces cheap, high quality, reasonably standardized robot arms. So many things like 3D printers or CNC machines have entered the consumer/amateur level price realm, but this seems to be something still largely unexplored. Seems to have Arduino/Raspberry Pi scale potential, but I haven't heard of a name/ecosystem that po…

There have been a few around, but the limiting factor (as you can see from the BOM in the link) is the cost of the actuators. They get expensive fast.

If they don't have to move fast, could you DIY an actuator with a stepper and a threaded shaft? Steppers are pretty cheap thanks to 3D printers.

Re: Low Cost Robot Arm

#127
post #40

Earlier quoted context omitted.

I’d use it to pick through and sort the massive pile of Lego my children leave behind after an Easter long weekend. Seems trivial to do identification based on the high quality corpus of block databases. Wouldn’t have to be super quick - you could just leave it running overnight. I’m sure someone’s written an interesting paper on the ideal sorting algorithm too (i.e. large things > small things vs. ‘just pick up and…

> Seems trivial Said like someone who's never tried it :) For a start you're going to need a camera. Maybe more than one. You want depth sensing? Even an cheap choice like a RealSense is going to add another $250 to your costs. And you'll need a sturdy mount for it, the robot's going to vibrate the table and you don't want to suffer motion blur. Got the camera in a fixed location, over the area you're picking from? T…

It’s trivial to fork one of the several open source projects focused on this problem.

Re: Low Cost Robot Arm

#128

I'm surprised (or perhaps very unaware) that there doesn't seem to exist a company yet that mass produces cheap, high quality, reasonably standardized robot arms. So many things like 3D printers or CNC machines have entered the consumer/amateur level price realm, but this seems to be something still largely unexplored. Seems to have Arduino/Raspberry Pi scale potential, but I haven't heard of a name/ecosystem that po…

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…

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.

Re: Low Cost Robot Arm

#129
post #99

Earlier quoted context omitted.

> Seems trivial Said like someone who's never tried it :) For a start you're going to need a camera. Maybe more than one. You want depth sensing? Even an cheap choice like a RealSense is going to add another $250 to your costs. And you'll need a sturdy mount for it, the robot's going to vibrate the table and you don't want to suffer motion blur. Got the camera in a fixed location, over the area you're picking from? T…

> Even an cheap choice like a RealSense is going to add another $250 to your costs fyi, Luxonis is selling some for $150, I'm still meant to try them but they look quite good

I happen to use a few of their cameras, and they generally work as advertised (satisfied Kickstarter backer for OAK D and OAK D lite, probably going to buy the OAK D pro at some point). But, while I did indeed pay less than 250 for them individually, their current active depth offerings are $350(and while my oak d is fine for my lit, varied environment, I do often wish it was a little more accurate). I thought the Lite was also around $200 but it's actually $150 as you said. It's a pretty good little platform for the price. Be sure to check out the experimental repo too : https://github.com/luxonis/depthai-experiments/tree/master/

Re: Low Cost Robot Arm

#130
post #89

Earlier quoted context omitted.

Arduinos are for prototyping, which makes the application fairly massive. The company I work for used them to develop one of our machines before we moved to a custom board. So, I'd say they are pretty useful.

Agreed, they certainly can be/are useful (and fun!), in a multitude of ways, but all too often I've also encountered peoples' "complaints" that they bought a bunch and now don't have a use case for it/are searching for one :)

That's because a toy engineering project is still an engineering project and will be way more work than you think it is, no matter how much work you think it is. It's hard to maintain that energy for long when it's not your day job (sometimes even when it is, tbh).
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