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CARA – High precision robot dog using rope

aaedmusa.com

181–188 of 188 posts

Re: CARA – High precision robot dog using rope

#181

What is the power consumption of these robots? I often wonder how limited and viable autonomous robots really are. When I look at Tesla's Optimus or Boston Dynamics' spectacular robots, how quickly do they need to be recharged?

> Cheetah robot can run 10.3 km with a 3 kg (465 Whrs) LiPo Battery

> the 33kg robot runs at 22 km/h (6 m/s). The total power consumption from the battery pack was 973 watts and resulted in a total cost of transport of 0.5, which rivals running animals’ at the same scale. The 76% of total energy consumption is attributed to heat loss from the motor, and the 24% is used in mechanical work

Cheetah was the robot built by Ben Katz, which then went on to electrify Boston Dynamics' dog.

Given we've had no major energy density or motor efficiency breakthroughs since 2015, I bet the above still holds. That's a 30 min run at full throttle BTW. So to escape the current killer bots, try to run above a 2h marathon pace for 30 minutes.

Source: https://dspace.mit.edu/bitstream/handle/1721.1/108096/Effici...

Re: CARA – High precision robot dog using rope

#182
post #156

Earlier quoted context omitted.

It could though. I don’t think the thought has occurred to him yet. He could make the stack twice as high and go around twice as far. If you moved the worm gear you could go farther, but I don’t know how he would do that with his drive. He could also go with narrower rope, and spread the load over more windings, which would give him more throw.

What are the loads on a drive in this use case? 35lbs robot bouncing on one foot would be 350lbs-ish of dynamic load? That can be handled with 2mm Dyneema.

At 2:02 he shows a working model with a smaller diameter cord than his earlier ones. Looked like he’s already using 1/8 or smaller.

Notice that the fastener bearing the weight of the cord is wrapped around two bends. If I recall my physics properly, each of those direction changes behaves like a pulley, halving the strain on the bight (dyneema is difficult to fasten though. Slippery bugger.)

No wait, he is already using 2mm: https://www.aaedmusa.com/projects/cara but it’s 2 ropes per leg, so maybe he could use 1/16” rope (1.6mm).

Re: CARA – High precision robot dog using rope

#183
This is great!

The video is the epitome of applying solid engineering principles. Where most stop at a minimal viable working example, it sails past that and gets real work done solving foundational problems, using a waterfall approach that expands leverage at each level of abstraction. Complete with outside-the-box thinking and insights which help save the viewer from repeating unnecessary steps, so that the end goal is reachable using modest tools and readily available materials.

I would gladly work with Aaed, and I must admit that I am jealous that he and his friends are living out the dreams that my friends and I had in the 1990s.

-

The Boomers didn't quite understand what we were trying to accomplish, as they had already done the important work of manifesting the equality that had previously been a dream in the US, so these sorts of innovations were gravy. But Gen X was raised on Star Wars, so will not be withholding mental energy from future generations. Unfortunately we are also victims of trickle-down economics, so have little to pass forward except for wisdom gleaned from the school of hard knocks.

We had everything we needed to build these exact types of projects except for the time and resources that were hoarded by our elders. So the vast majority of us worked our lives away, barely making rent by prospecting the internet as miners for people with money, without ever striking gold in the vast majority of cases. Then watched as the fruits of our labors were used to build McMansions, expand monopolistic enterprises like private equity firms, or be simply wasted on frivilous expenses instead of reinvested in automations to create residual incomes. This led to us developing mental health issues like addiction due to the misalignment between the lives we had to live vs what might have been.

Then we lost our heroes, like when Y Combinator went from an indie startup funder to a vetting VC like all the rest. And when Elon Musk pulled up the ladder behind him after accomplishing so much, then used his wealth to dismantle the social safety nets which make indie work possible. I don't believe that these statements are political, as they objectively describe the unwritten history of how some became so wealthy while most struggled, and the irony that I write this as I stand on the shoulders of those fallen is not lost on me.

Now we have everything we need to build R2D2 and C3P0 right now, today.

So I'm hopeful that the next step will be to create a meta economy within the status quo that distributes resources outside of the artificial scarcity created by the previous dominant systems of capitalism, socialism and communism. I believe that a gift economy loosely resembling solarpunk has the potential to liberate humanity from forced labor so that every individual has the opportunity to self-actualize in a reasonable time frame and still experience the joys of leisure time and youth.

In practice, this will expand wealth redistribution models like Patreon and the WiX Toolset maintenance fee under an umbrella similar to the Humble Bundle, to level out long-tail effects and socialize gains while privatizing losses. Note that this works exactly the opposite of how most major economies work in the world, with the exception of nations like Norway which uses its sovereign wealth fund from nationalizing its oil companies to pay its citizens a pension that may someday become UBI.

I realize that these points are mostly excuses and platitudes. But they are in no way meant to diminish the efforts of hackers - on the contrary, they are intended to bolster them by adding meaning to the work and convey why it's so important to those that came before.

So I write this out today to record in the annals of history that the nature of the problems we face is no longer technical, but spritual.

Re: CARA – High precision robot dog using rope

#184
post #116

Earlier quoted context omitted.

Who cares if it's weird? Why are you saying "weird" as if that were a bad thing? It's just a derogatory synonym for "unusual". A take would have to be weird to be a contribution to the conversation, because if it's not weird, it's a widely held opinion we all already know, and nobody gains anything by reading it. What matters, given that it meets the minimal bar of weirdness to be potentially worthwhile, is whether i…

I'd call it delusional than weird. US is clearly controlling Ukrainian churn rate so that Russian military and Ukraine as nation burn down at the same rate into disappearance so that the postwar Ukraine can be rebuilt with more Western leaning meatbags from surrounding nations. And some of people here are framing exactly that as utopian bloodless fights of machines. Calling it weird is itself almost weird.

Never attribute to malice something that which is adequately explained by stupidity. It's true that US restrains Ukrainians and the war drags on but US does this out of fear of nuclear war with russia. It's silly, but you have to understand that US for many decades built up the marketing myth of russia as a scary superpower. Only in opposition to this great and strong evil they could see themselves as the great and strong good. To facilitate this they told everyone that russia is strong boogyman so much that they themselves believed it and can't shake off this belief even though russia repeatedly displays how weak and terrible at everything it is.

Re: CARA – High precision robot dog using rope

#185
post #179

Earlier quoted context omitted.

That's why there's never been a war between two nuclear-armed countries: everybody is shitting in their pants because of exactly that logic. Presumably we'll find out when the PRC invades Taiwan. However, if that doesn't end up with a radioactive wasteland, we'll probably find out shortly afterwards what happens when every two-bit drug cartel or extortion mafia can cheaply assassinate anyone, anywhere in the world, w…

> However, if that doesn't end up with a radioactive wasteland, we'll probably find out shortly afterwards what happens when every two-bit drug cartel or extortion mafia can cheaply assassinate anyone, anywhere in the world, with an ambush drone. I wonder what's stopping them right now. They used drones to smuggle drugs already.

Ignorance. More specifically, diffusion of innovations.

Re: CARA – High precision robot dog using rope

#186
post #51

Earlier quoted context omitted.

The point is that those decimal places don't have to be zeros. 7.893 is just as precise as 8.001.

Yet for some reason unknown to me, people get annoyed when you tell them „let us meet at 13:37. that is no more accurate than let us meet at 14:00 hours”

1. It's easier to remember.

2. Do you actually say fourteen-zero-zero or just fourteen? If the latter, that's your answer right there.

Re: CARA – High precision robot dog using rope

#187

this guy's work is pretty amazing I whole heartedly believe that I'll own a gang of (armed) quadrapets for home/property/personal protection within the next 10 years. I'm equally worried that once these become commodities they might be worse than an electric scooters have become to us bipeds on sidewalks but on balance I can't wait

> a gang of (armed) quadrapets for home/property/personal protection

You're assuming you'll be the only one with those capabilities aren't you?

Re: CARA – High precision robot dog using rope

#188

It's amazing what he's done in terms of the robotics, and the presentation of it to the viewer. I'm amazed at the quality of cinematography on the internet these days. The implications of the tools we now make available for use in our own personal workshops are still being discovered, and will be for some time.

As someone who workedon projects, written documentation(even notes) let alone video format is even more time consuming than the work itself. It's extremely beneficial for long projects and continuation, but really tedious. Kudos to all the applied tech youtubers out there.
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