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points by nhnifong 4 days ago | 0 comments

Hi there, I'm Nathaniel, the creator of this robot. Thanks for posting it :) If you have any questions feel free to ask.

Can it kill you? no probably not. The tension limit kicks in and lets the line out if you pull too hard.

Will it work in a room with a ceiling fan? usually its fine since you can lower the work area ceiling to exclude the fan.

Will it make my kids learn to not pick up after themselves? They never will anyways.

[–] dingdongditchme 4 days ago

Awesome project! What you've built is a Cable-Driven Parallel Robot, and since you are using gravity to keep the cables in tension it is a suspended cable-driven parallel robot. Using the four cables you are able to move a point in 3D space. I happen to know this because I wrote my phd on the accuracy of these types of robots and their kinematics. At that time Jean-Pierre Merlet was probably the most famous/prolific researcher on this topic (https://www-sop.inria.fr/members/Jean-Pierre.Merlet/merlet_e...). You may also have heard of a company in Germany trying to commercialize this technology on a slightly bigger scale: https://redcablerobots.com/en/. There is also a conference on these types of machines in Europe: https://cablecon2027.sciencesconf.org/ the original being organized by Andreas Pott (another high impact sholar on this).

I have not worked in this field for many years but had a fun time learning about a very wide array of topics.

[–] khriss 4 days ago

This kind of reply is what makes HN the place on the internet for nerds :-)

No matter how niche the topic, if it's in anyway related to technology or science, you will likely find a genuine expert responding to you.

I just hope and pray this continues so that we have at least one place that is reminiscent of the old internet.

[–] dingdongditchme 3 days ago

hard agree! I've read so many insightful comments over the years. Didn't expect for it to be me one day! The project here is really cool and competes with the robots we built fair and square; and we had several engineers building and designing these.

[–] 4star3star 3 days ago

Since my elderly parent has fallen a few times and now must use a walker, I've often daydreamed of an overhead cable system hooked into a harness. Is there anything like this in development?

[–] dingdongditchme 3 days ago

That's actually exactly what J.P Merlet was researching about! But to be honest I am not sure if it ever got out of the university prototype phase. I know of systems in care-homes which are like movable cranes but they require big doors and even flooring like you would find in a hospital. Because handling cables is actually tricky and you have longer setup times than you would expect the only commercially successful cable robot that I am aware so far is the skycam other comments have mentioned.

[–] throwup238 3 days ago

It’s stuck in R&D for some reason [1]

[1] https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.#Death

[–] ajolly 13 hours ago

" death was ruled a suicide by the coroner"

[–] 0xdeadbeefbabe 4 days ago

If I had this I could get a roomba. Does that make sense?

[–] financetechbro 4 days ago

Totally agree. I would love a roomba but I have a dog so clutter in the living room is inevitable even after a clean up. This bot could sync with the roomba (or other robot vacuums) to ensure a space / path is clear before it is vacuumed

[–] ithkuil 4 days ago

can it just carry around a normal vacuum? no need for wheels when you can fly

[–] embedding-shape 4 days ago

Create a little station in one corner, and make the whole arm/pulley system able to switch the attachment/tool, so it can first pick up all the stuff, then change the tool to a vacuum, then once done, change a tool to a mop, and so on :) A N-in-1 system!

[–] ithkuil 3 days ago

you can also program it to turn itself off

[–] sixothree 3 days ago

This is actually what I like about my roomba - it forces me to clean up objects from the floor. So yes, I'm doing manual labor. But I'm not hating myself every day for not vacuuming.

[–] bearfood 4 days ago

If I get this, could it carry my Roomba up stairs so it'll cover my whole house?

[–] Terr_ 4 days ago

From a quick search, most models will be heavier than what this can lift, even at low heights in the center of the room where the stress on any particular cable is minimized.

[–] R1D3R 4 days ago

> Can it kill you? no probably not. The tension limit kicks in and lets the line out if you pull too hard.

Is there a physical safety? The anchors are attached to the wall, do they release with less tension than a human airway can withstand? I have experienced injuries that would prohibit me from exerting a "backpack" of force over my head.

[–] nhnifong 4 days ago

There is a tension limit of 28 newtons on any single line. Beyond that, the motors release with a damped motion. This can be lowered, at the expense of payload capacity.

[–] reacweb 3 days ago

Is there also a speed limit ? A fast moving object of 2kg may be dangerous.

[–] R1D3R 4 days ago

How far will they release? Is that physical or software? If the line is wrapped around my neck and anchored to the wall how does the motor releasing help me? I can see industrial applications but it seems like a dangerous thing to have in a home.

[–] King-Aaron 4 days ago

FYI they said the tension limit is 28 newtons.

It takes about 38 newtons to lift a 4 litre bottle of milk.

It'll be okay.

[–] R1D3R 4 days ago

The lines are anchored to the wall. There's no tension release on that. The gripper in the middle of the room unwinding some line won't prevent you, your child, or a pet from hanging themselves from the anchored end.

[–] thrownanchor 4 days ago

The winch is in the corner at the wall. The fixed end is at the tool. You can't hang yourself.

[–] R1D3R 3 days ago

Ah, that does seem better.

[–] solyin 4 days ago

A tension limit 28 Newtons means the average child of age one or up is heavy enough to break the line.

[–] R1D3R 3 days ago

The line doesn't have a 28 newton breaking strength. That's the point at which the motors release. The line itself is presumably much stronger.

[–] King-Aaron 4 days ago

Unless you're using tensioned steel wires, I don't think even a child is going to have problems escaping from some fishing line.

[–] andrewstuart2 4 days ago

So it probably can't kill you with blunt force trauma but it could drop something toxic into your drink while you're in the other room. Which, you know, assumes some sort of hostile intent that a robot can't have on its own lol. So it can kill you but probably not accidentally.

[–] nvme0n1p1 4 days ago

If your adversary wants to murder you that badly, I doubt they're going to give up when they find out you don't have a Stringman wired up in your kitchen.

[–] King-Aaron 4 days ago

"Any machine can be a blender if operated wrongly enough"

[–] WarcrimeActual 4 days ago

I’m going to go out on a limb and say that you should just have better survival instincts than a toddler and not let the line wrap around your neck. And if you do have toddlers, maybe keep them away from the hanging machine.

[–] nextaccountic 4 days ago

If that's the official stance, then this robot will kill people. You can't expect people to never leave a toddler in the same room with the robot, unless they fully realize the implications of having a killer robot at home. Otherwise the consumers are being deceived

Products in the real world need to be better than that

[–] Closi 4 days ago

> If that's the official stance, then this robot will kill people. You can't expect people to never leave a toddler in the same room with the robot, unless they fully realize the implications of having a killer robot at home. Otherwise the consumers are being deceived

There are plenty of things sold that toddlers can kill themselves with, this is why parents have to spend ages 'toddler-proofing' their house. Same with dogs - supermarkets sell lillies but I can't have them in my house as I have a hungry dog that eats anything.

It's OK to have products which are not suitable for people with pets or kids.

[–] doctorpangloss 4 days ago

the discourse in hacker news is turning into a neurodivergent, overdramatized concern trolling competition.

[–] piloto_ciego 4 days ago

I'm getting frustrated with this sort of thing myself. Good lord people, chill.

[–] komali2 4 days ago

"Just let people be responsible for themselves" would work if we hadn't built a society that neutered everyone's ability to take care of themselves by gutting education systems and disconnecting people from political participation and social responsibility.

Tldr have you met people? There's a reason seat belt laws exist. If we're going to let companies sell things to this population we've fostered and not take our own responsibility, we have to put it on the companies.

A quick browse through any of the shock content subreddits will reveal a lot in terms of average people's understanding of risk.

[–] SR2Z 4 days ago

This might kill like three toddlers if one is installed in every home in America.

It sits several feet above the ground and is attached to the ceiling ffs. Unless you have the world's most clueless toddler who waits for this to fall just to sprint full speed at multiple ropes and you just so happened to install the winches with concrete bolts it seems pretty unlikely.

The toddler:robot win ratio is gonna be like 100:1.

[–] meigwilym 3 days ago

Locally, a two year old managed to kill himself by getting tangled in window-blind string. All toddlers are clueless, and no one wants theirs to be the outlier.

[–] TheBicPen 3 days ago

I agree with the rest of your comment but

>The toddler:robot win ratio is gonna be like 100:1

is beyond unacceptable for a consumer product.

[–] R1D3R 4 days ago

Toddlers exist in homes. It is their natural habitat. Keeping them away seems like a reasonable precaution. I'm glad we agree on that.

[–] sandworm101 3 days ago

It has cameras. Just tell it to retreat to above head height when it sees a person, or motion.

My worry is cats. I know cats that will go to war with such a robot. String, jerky movements, vertical retreat... cats are built to war with such things.

[–] mlyle 3 days ago

This is awesome!

I wonder: how much would a 5th actuator in the middle of the room help? Seems like it might add a lot of damping, precision, and reduce the effect of sag a lot having only 50-71% of the original span and always having a line that's close (or much closer) to pointing "down".

[–] neuronexmachina 3 days ago

Tangential: You might want to add some og-tags to your site (or at least a meta-description), so link unfurlers like those in Slack/FB will display a description/image.

[–] dandare 4 days ago

HI, I am sure you considered it, but wouldn't the design be better with a 5th cable going straight up and down from the moving point?

[–] quaffcode 3 days ago

How could it go straight up and down? As the robot moves around the room, the anchor for the vertical cable would no longer be directly above the robot.

[–] philote 3 days ago

I assumed the 5th cable would be directly connected to the robot, to lower and raise it straight up and down. So, cables from four corners of the room to the center point where the 5th cable is, and the robot hangs off that 5th cable and can raise/lower itself.

[–] its-summertime 4 days ago

https://youtu.be/AWig98GVIno?t=155 might be worth looking into with regards to the descending rod, to make its length controllable without taking up much space

[–] joshspankit 4 days ago

How does it handle the change in slack over time as the cables naturally deform?

[–] gf000 3 days ago

I guess via the camera?

[–] crote 4 days ago

What's up with the giant USA flag in the 3D model of the room? Will it hand over the control keys to China if it isn't constantly reminded of its nationality? ;-)