Every use case is completely different and is a lot of work. Even when you get something working, accidentally shake the desk or crash the arm into something and all your coordinates are broken and you have to start again.
Not to mention the actual mechanics are really complicated - to have a meaningful payload at 50cm reach you end up with really high torque at the base joints (which also need to have super-high accuracy), which requires expensive gears and motors. None of that is cheap.
Then you get to safety - an arm that has a useful payload is also quite heavy, and having that amount of mass flailing around requires safety systems - which don't come cheap.
It's a bit like hardware no-code - you can't make an easy to use robotic arm because programming it is inherently hard. I think the only thing that will change that is really good AI.
Do you know if anyone has tried building an arm that uses spatial positioning techniques from augmented reality, like structured light or pose tracking[1], to understand the position of the arm in space without resorting to "dead reckoning"?
It seems like that kind of approach would increase the physical tolerance and reduce the programming complexity, since you know both a) where the arm is supposed to be, and b) where it actually is.
[1] https://en.wikipedia.org/wiki/Pose_tracking#Outside-in_track...
The more usual application of multi-camera setups etc. is in path planning and scene understanding, not low level control.
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.
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.
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."
^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.
Look at this BOM: https://docs.google.com/document/d/1_3yhWjodSNNYlpxkRCPIlvIA...
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.
$3 will get you a basic Arduino Nano clone.
I've built a lot of custom arduino-based projects for other people and a substantial fraction of them are the "I bought a bunch of stuff, but I don't have time to learn how to program it" types.
Lots of automation works this way, but it actually limits the applications quite a bit.
A robot that can safely work along side people (i.e., a "cobot") and adjust to environment changes and changing work patterns is a whole different beast.
I think the limiter on smaller arms is quality servos with real location encoders - this one costs a couple hundred bucks for motors.
Not claiming the software is easy! But I think sourcing parts is (or has been) really hard.
Not a robot arm, but I worked on a project where the customer wanted to use a commercial motion platform as part of a simulator-based training system for boats. They thought they could just put it in the corner of their boat shed and get training but were amazed when they realised how dangerous it could be to passers-by, especially if it moved unpredictably when someone was standing nearby without paying attention. It went from 'we just need some crowd control barriers' to a full metal cage that was also integrated with the building fire alarm system so that it would stop cleanly if there was some sort of emergency elsewhere.
Other motion-platform-based hilarity ensued when it was discovered that the commercial software model they were using to drive the sim could in some circumstances capsize the virtual boat.
[1] https://www.youtube.com/watch?v=UerxNyu147g [2] https://mobile-aloha.github.io/
This typically won't be accurate enough for closed loop kinematics, especially at any sort of speed.
Many medium sized arms are quite capable of generating forces that can kill a person.
Which is partly why SCARA is popular with amateur robot arms, the maths is simpler.
I wish there was more visibility here without requiring a PhD.
[1] In the order of 1:100, see e.g. https://www.harmonicdrive.net/
These do exist, it's just that "reasonably cheap" is typically low - mid 5 figures for any sort of reach an payload.
Which of those can/cannot be done and why?
The most common designs of six-axis robot arm don't have the 'rotate forearm sideways' joint needed to arm wrestle.
> - Handwriting notes for small jewelry brand?
Possible: https://en.wikipedia.org/wiki/Autopen
> - Drink mixer?
Possible: https://www.makrshakr.com/ (arguably more of a showy entertainment item than anything else)
> - Handing towel when in the bathroom, then getting a new one?
Manipulating flexible materials is difficult. As is navigating through a house with locked bathroom doors and suchlike.
> - Setting up my morning espresso?
Depends if you're willing to broaden your definition of 'robot' to include bean-to-cup machines.
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 done already with a commercial 2D plotter: https://www.axidraw.com/ . It costs twice as much as this arm, but you don't have to build it and it already has "software for realistic handwriting" and there's a company to get support from.
> "Handing towel when in the bathroom, then getting a new one?"
Is the arm big enough to be useful for that? It appears to be shorter than a typical human arm so it would be cheaper, simpler and quicker to put the pile of clean towels a foot closer to the shower where the robt arm is sitting, and not have the robot arm at all. Plus you wouldn't have to deal with electricity in the bathroom or dripping water on the robotics as you reached for the towel it was handing you. (Are you thinking of a robot arm with cameras for feedback of where it's positioned? Cameras in a bathroom won't be popular with everyone no matter how much you promise they are innocent).
> "Setting up my morning espresso? (grinding the beans and turning on the coffee machine)"
Simpler and cheaper done with a timer mains plug which you can get for under $10. Put the beans in and load up the coffee machine the night before (work you'd have to do anyway) and have the timer start them in the morning. If you expect the robot arm to unseal a bag of coffee beans, measure some out, deposit them in the grinder, close the grinder, and close and seal the bag after, you'll wake up to spilled beans and unsealed bag a lot of days before you get that working reliably. Instead of $250 plus weeks of effort to speed up this 2 minute task(!) you can get a Keurig / Nespresso pod coffee maker for less than $100.
> "Drink mixer?"
How much spilled wasted alcohol, plus time of disassembling and cleaning your robot arm and the surface it sits on, and the floor, or finding the bottles, unscrewing the tops, handing them to the arm, waiting for the arm to slowly pour them which you could have done quicker, then putting the tops back on and putting the bottles away yourself, then putting the drink stirrer into the arm, then waiting for it to mix the drinks which you could have done yourself quicker, before you decide this was not a good use of time or money? (How often do you drink mixed drinks anyway?)
The robot isn't going to learn to do the task better next time like a human could so if you have to get involved in the task at all, you may as well do it yourself. And if it's a 15 second task like "reaching for a towel" what are you doing with your life trying to automate that? Roomba saves a lot of time, a lot of annoyance, it could be worth it even if it does an inferior job - because you can leave it running over and over and over. Same with a robot lawnmower, if you just glance around to make sure there's no pets or children in the way then let it go, it can save you a good chunk of time and if it goes wrong you just get a patchy lawn or dusty floor and it can retry tomorrow. But handing you a towel or mixing you a drink saves you almost no time, but if it goes wrong you get a broken bottle of sticky drink all over or a pile of towels on the floor, which has undone months of 'time saved' in one go.
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.
Do you genuinely think they will improve to the point of having finger style grippers, dexterity and adaptability to grind coffee, mix drinks and pick towels, and be on sale to the public, safe for use in the home, for $250 (or $2500) by Jan 1st 2030? I would be very surprised.
(Can you get a robot arm today, for any price, to help a quadraplegic open their mail, bring a drink with a straw in it to their mouth, lift them into a sitting position, hold a book in front of them and turn the pages, or ... do anything helpful? I'm not aware of any, but haven't been looking specifically).
Yes you could probably build a robot today which hands you a towel from a pile, reliably and swiftly, or selects the bottles of alcohol and opens them and pours and mixes a drink - in a carefully controlled and lit environment where none of the lids or corks are stuck and the glasses are all a similar shape and size and nobody is allowed to be near it - I don't say it's impossible with today's tech, but it would cost a lot more than $250. A hundred or a hundred thousand times more, while being far far more limited than a human.
[1] https://arstechnica.com/gadgets/2022/04/boston-dynamics-stre...
Hardware generations are typically closer to a decade than a year. Robotics is moving fast these days, but not that fast.
Most mechanical things require you to optimize for cost or quality