I've watched and re-watched Aaed's videos on the capstan drive, it's great stuff. High speed, high torque, compliance, effectively no backlash. It's fascinating to watch a legit engineering mind at work.
So, Aaed was our intern last summer - and he’s the real deal. I got to work with him on some really cool bespoke robotic end-effectors and the guy has great design instincts. Picked up mechatronics skills like a sponge, grokked hamming codes in like 30sec from a whiteboard doodle. Super hard worker too, he would stay late in the electronics lab to work on the motor design for what turned out to be CARA - we had fun testing the backlash one evening and ever since I’ve been trying to shoehorn one of those actuators into a project.
Potential and active founders here should consider reaching out (i think a startup setting would suit him better than corporate research), though he’s obviously got his own stuff going on and a degree to finish!
I recently found his videos also. It's one of those things that gets my mind bubbling with ideas for things I want to make, never enough time to do them all though (and this breadboard beside me is asking for attention)
It does make me wonder about the algorithm, Quite a lot of things I find on Youtube turn up on HN a week or two later. I'm not sure if this is an indicator of the effectiveness or failure of the algorithm. It is definitely succeeding in finding videos popular with some people and showing it to more who might share that interest. The question is, are the things I (and consequently many others of similar interests) see the best of all there is, or a subset of the excellent videos out there that happen to get noticed.
I sometimes find channels that are years old with a goldmine of good information. That suggests that there is more good stuff out there than what I see. Were they just unlucky that I didn't see them before? Am I lucky to be seeing them now? It also might be that it is not luck but the algorithm has arbitrarily decided that the video has some special factor that requires promotion or that I have passed some arbitrary threshold of perceived character development that makes me supposedly now interested in such things.
He's easily one of my favorite content creators. Ofc, there are much better engineers, domain experts or more entertaining people on youtube, but he strikes a very enjoyable balance.
I wanted to start writing a list of other tech related, pop-sci and industrial-design Youtubers I kinda enjoy, but noticed just how many channels I'm subscribed to... If there's any interest, I'll drop it, just tell me. Meanwhile I have some filtering and sorting to do.
I haven't watched the one about the dog, but the one with the initial explication of capstan drives [0] was excellent. I've been dreaming about it for the last year, especially since about the same time another person started working with the da Vinci robot actuators which use cables to generate find motion.
"back in the day", we used capstans to drive film (movie) rolls around the scanning aparatus. Both high speed and precise without backlash. Great stuff. Somehow I always thought maybe lack of high torque is the issue more people aren't using them or wear and tear.. but, apparently not?
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.
I watched this last week and my jaw was on the floor. He's both a great technician, and he has the personality to make it interesting. He walked through his testing strategy far enough that you could understand his methodology and the thought process behind it, but didn't belabor it by making us watch it all. Banger!
I'm going to tell my 12 year old that when he leaves education he wants something like this on his personal web site:
"CARA (Capstans Are Really Awesome) is my latest quadrupedal robot, following ZEUS, ARES, and TOPS. Built over the course of a year, CARA is easily my most dynamic and well-designed quadruped yet."
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.
My understanding is that those motors he uses are pretty special. And I would expect “efficient” to be part of that special. You’re optimizing for torque and accuracy per unit of mass and energy in this sort of space. I know he talked about them in earlier videos but I no longer recall the details.
Well, it probably wasn't that much effort. When you're 3D printing you're going to end up printing everything 2-3 times anyway, so why not dial in the ratio while you're at it?
And you can't really declare your design is "high precision" and present yourself as someone others should take transmission design advice from if you aimed for a gear ratio of 8 and achieved "somewhere around 7.9 to 8.2"
> Also, I wonder how resistant this mechanism is to wear and fatigue.
He actually discussed this in an earlier video for his initial tests on the capstan drive. He ended up testing the rope he used for around 358 hours (two weeks) on continuous use in the drive itself with very low backlash
Because when a real engineer puts 2 and 2 in and gets 3.8 out, it vexes them and they want to at least know why they can’t get 4. He’s trying to make a machine that does what he told it to do, so that he understands what is actually happening.
I think it's about kinematics, the more precise your gears the better the model fits the real world.
That's why pro crews don't use gears and ropes. At high impulses deformations and elasticity throw the kinematics off what's actually happening. Modeling the deformations and the elasticity is a computational no no. Instead what you see is the motors right on the joints.
At least that was the case last time I had a look at robotics.
I think he'll have success with youtube/vlogging more than getting into the corporate world honestly - especially with some healthy sponsorships and great projects like this.
Thanks for sharing this! What a treat of a video. It's a fun project, and it's presented very well. This guy has a talent for communication - the video was super clear and well explained. I really admire that ability and I want to get better at it.
Also the Spanish words for "face" (no me gusta tu cara, boludo) and "expensive and female" (esa computadora es re cara, boludo). https://en.wiktionary.org/wiki/cara tells us it also has meanings in Aragonese, Asturian, Catalan, Crimean Tatar, French, Galician, Indonesian, Italian, Latvian, and another couple dozen languages.
Breaking Taps on YouTube did a really awesome video on a somewhat similar mechanism (I'm no mechanical engineer haha, it was new to me!), rolling contact joints. I love the idea of using string/ropes. Worth checking out as well if this kind of stuff interests you! https://www.youtube.com/watch?v=TQiLLcumqDw
Fascinating! I want to get into this type of stuff. But I have no idea where to start, I just have just a CS degree and 3 years experience as a developer.
I recommend a Brachiograph build. It will introduce you to some fundamentals of PWM and inverse kinematics. It is well documented but not cookie-cutter. Using a Raspberry Pi will give you more direct access to running the servos than the microcontroller experience. All the parts are infinitely reusable afterward if you don't want to keep it around.
Sample Supply List for $80 budget:
Pi Zero with header $20: https://www.adafruit.com/product/6008
Power supply $9: https://www.adafruit.com/product/1995
SD Card $10: https://www.adafruit.com/product/1294
Three hobby servos $18: https://www.adafruit.com/product/169
Breadboard wires $5: https://www.adafruit.com/product/153
Breadboard $5: https://www.adafruit.com/product/64
Glue, popsicle sticks, pen and paper $10
Arduinos and hobby servos. No, neither of them are "industrial grade" and yeah, you'll reach their limits pretty quickly, but building a physical thing that does stuff is (in my experience) a huge motivator.
Or if you're already all over the basics, figure out what kind of stuff you want to build and then try and build it. :)
I remember a post previously related to him here on HN but I am surprised at how I forgot about him and how cool he is to build all these incredible stuff and also teaches in his videos. I am subscribing so that I never miss anything from him again.
Very cool robot dog and interesting video!
Can the dog climb stairs? Isn't capstan drive temperature sensitive, e.g. the ropes will be shorter in cold and longer in warm wheather?
New here and just stumbled upon this. Seen these "robodogs" live in Vegas mining conference. The usage is picking up, their functionality and range of movement is so much more advanced now, and the list of actions they can complete much more complex. Awesome stuff!
How do we make such robots intelligent? Like you only tell it to learn to jump the rope and then it goes through trial and error(s) to figure out a way to do it, and if it can’t and needs a physical upgrade then it tells you that? (Like a certain gear ratio etc)
What a horrible video is this, with the robotic translated AI voiceover?
Update: Ah, weird, if I watch the non-embedded one on youtube it is the original in English with normal sound. It's the one embedded on his web site which has AI translation to German.
That's not the video's fault, but YouTube's. YouTube has started adding automatic AI voiceover translations to all videos, unless the uploader explicitly disables them for each single video. It's opt-out and the option is well-hidden, so most uploaders will not disable it.
As an end user, there's nothing you can do to prevent from seeing them. But you can change the audio track to the original while the video is playing.
It might be fun to optimize the shape of the rolling contact surface of the capstan drive away from cycloid to make it even better suited for specific application, like a robot dog leg that smoothly runs for miles.
> Programming takes the cake for what is both my most and least favourite part of any build. Nothing quite makes you pull out your hair and ask yourself, 'What the heck have I gotten into?' Like spending weeks programming a robot that just won't work. Eventually though, you fix that one line of code that makes all the difference. And then it's smooth sailing. Well, kind of.
I feel this deeply, also this whole video is quality content.
It's just a gut feeling but I'd trust a feedback based backlash elimination mechanism more than rope based, especially in the long run and/or with a large deployed base.
There is a weird mixture of hope and dread in me as I watch this. I am ridiculously excited over a person like me being able to mess around with something that, until recently, was gated behind, well, a lot of hard problems to overcome ( I am only now slowly getting through old Peter Scott's robotics to get some perspective ). By comparison, it should be so much easier to explore aspects of robotics that may go beyond strict math and engineering.
Gated how? It's all on textbooks, industry standards, Internet, everywhere. You could buy a KHR-3 without even driver's license for $1.5k cash for past ~20 years. I guess CUDA was technically gated behind "I swear I'm not a bad guy" button, but that was it.
I'm surprised that Ukraine isn't DIYing full-on solid motor cluster SAMs and armor piercing ATGMs. I thought those kinds of devices were something just about any sufficiently developed country can do in days to weeks should such national emergency arises and all bets were off, except nations in peacetime has moral obligations to do no evil.
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
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.
I don't think it is fair to downvote this comment. It is a genuine concern and should be addressed. Amusingly, given that the thought has entered mass consciousness by means of question on 'whether all this is a simulation', matrix ( the animated series ) explored this question a little and it is interesting in how the timeline aligns with what the movie presented.
On the flip side, capitalistic / private / special interests both controlling the progress and having the most ability to utilize it to further centralize power and wealth is deeply concerning. We can already see more controversial figures involved in AI using it to spread their personal viewpoints.
It feels really easy to see how our jobs/labor and therefore our capital and therefore our value in the modern system are being directly attacked by these capabilities and deeply concerning to imagine how further centralization of power could be good for the masses.
btbuildem|7 months ago
monuszero|7 months ago
Potential and active founders here should consider reaching out (i think a startup setting would suit him better than corporate research), though he’s obviously got his own stuff going on and a degree to finish!
Lerc|7 months ago
It does make me wonder about the algorithm, Quite a lot of things I find on Youtube turn up on HN a week or two later. I'm not sure if this is an indicator of the effectiveness or failure of the algorithm. It is definitely succeeding in finding videos popular with some people and showing it to more who might share that interest. The question is, are the things I (and consequently many others of similar interests) see the best of all there is, or a subset of the excellent videos out there that happen to get noticed.
I sometimes find channels that are years old with a goldmine of good information. That suggests that there is more good stuff out there than what I see. Were they just unlucky that I didn't see them before? Am I lucky to be seeing them now? It also might be that it is not luck but the algorithm has arbitrarily decided that the video has some special factor that requires promotion or that I have passed some arbitrary threshold of perceived character development that makes me supposedly now interested in such things.
DeepSeaTortoise|7 months ago
I wanted to start writing a list of other tech related, pop-sci and industrial-design Youtubers I kinda enjoy, but noticed just how many channels I'm subscribed to... If there's any interest, I'll drop it, just tell me. Meanwhile I have some filtering and sorting to do.
adolph|7 months ago
0. High Precision Speed Reducer Using Rope: https://www.youtube.com/watch?v=MwIBTbumd1Q
1. Building a DIY Surgical Robot https://www.youtube.com/watch?v=d_8rHKrwr-Q
Keyframe|7 months ago
dyauspitr|7 months ago
foobarian|7 months ago
mikewarot|7 months ago
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.
ErigmolCt|7 months ago
3abiton|7 months ago
aldousd666|7 months ago
AIorNot|7 months ago
https://www.aaedmusa.com/
beachy|7 months ago
"CARA (Capstans Are Really Awesome) is my latest quadrupedal robot, following ZEUS, ARES, and TOPS. Built over the course of a year, CARA is easily my most dynamic and well-designed quadruped yet."
abtinf|7 months ago
Much better for someone to fund a startup run by him.
andrewstuart|7 months ago
dev0p|7 months ago
lhmiles|7 months ago
throwaway2037|7 months ago
It definitely gives off Elysium (film) vibes.
einrealist|7 months ago
ovi256|7 months ago
> 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...
hinkley|7 months ago
mnurzia|7 months ago
fusionadvocate|7 months ago
Also, I wonder how resistant this mechanism is to wear and fatigue.
michaelt|7 months ago
And you can't really declare your design is "high precision" and present yourself as someone others should take transmission design advice from if you aimed for a gear ratio of 8 and achieved "somewhere around 7.9 to 8.2"
jedimastert|7 months ago
He actually discussed this in an earlier video for his initial tests on the capstan drive. He ended up testing the rope he used for around 358 hours (two weeks) on continuous use in the drive itself with very low backlash
https://www.aaedmusa.com/projects/capstandrive
https://youtube.com/watch?v=MwIBTbumd1Q&t=10m
hinkley|7 months ago
throwawayffffas|7 months ago
That's why pro crews don't use gears and ropes. At high impulses deformations and elasticity throw the kinematics off what's actually happening. Modeling the deformations and the elasticity is a computational no no. Instead what you see is the motors right on the joints.
At least that was the case last time I had a look at robotics.
skeeter2020|7 months ago
Isn't having more decimal places the exact definition of precision (vs accuracy)?
sabareesh|7 months ago
ErigmolCt|7 months ago
pillars|7 months ago
tgtweak|7 months ago
TheBozzCL|7 months ago
ErigmolCt|7 months ago
amelius|7 months ago
s_dev|7 months ago
Keyframe|7 months ago
kragen|7 months ago
unknown|7 months ago
[deleted]
ZeWaka|7 months ago
syarb|7 months ago
Breaking Taps on YouTube did a really awesome video on a somewhat similar mechanism (I'm no mechanical engineer haha, it was new to me!), rolling contact joints. I love the idea of using string/ropes. Worth checking out as well if this kind of stuff interests you! https://www.youtube.com/watch?v=TQiLLcumqDw
andrewstuart|7 months ago
csours|7 months ago
heap_perms|7 months ago
adolph|7 months ago
https://www.youtube.com/watch?v=u4Jh1daCl60
https://www.brachiograph.art/
https://github.com/evildmp/BrachioGraph
taneq|7 months ago
Or if you're already all over the basics, figure out what kind of stuff you want to build and then try and build it. :)
ErigmolCt|7 months ago
sarthaksoni|7 months ago
Time to raise my own bar.
srameshc|7 months ago
jankovicsandras|7 months ago
ezekiel68|7 months ago
nickdothutton|7 months ago
unicorn_chaser|7 months ago
micromacrofoot|7 months ago
taneq|7 months ago
Edit: And yes of course, in hindsight, you don't build a leg unless you're planning to build a thing with legs.
cryptoegorophy|7 months ago
scotty79|7 months ago
froh42|7 months ago
Update: Ah, weird, if I watch the non-embedded one on youtube it is the original in English with normal sound. It's the one embedded on his web site which has AI translation to German.
indigo945|7 months ago
As an end user, there's nothing you can do to prevent from seeing them. But you can change the audio track to the original while the video is playing.
laughing_snyder|7 months ago
otikik|7 months ago
scotty79|7 months ago
mikestaas|7 months ago
I feel this deeply, also this whole video is quality content.
amelius|7 months ago
heeton|7 months ago
A4ET8a8uTh0_v2|7 months ago
numpad0|7 months ago
I'm surprised that Ukraine isn't DIYing full-on solid motor cluster SAMs and armor piercing ATGMs. I thought those kinds of devices were something just about any sufficiently developed country can do in days to weeks should such national emergency arises and all bets were off, except nations in peacetime has moral obligations to do no evil.
bmau5|7 months ago
joeevans1000|7 months ago
hypertexthero|7 months ago
Geordi LaForge reminds me of Aaed.
yrcyrc|7 months ago
fitsumbelay|7 months ago
Mawr|7 months ago
You're assuming you'll be the only one with those capabilities aren't you?
FugeDaws|7 months ago
kokorikooo|7 months ago
zackmorris|7 months ago
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.
evrennetwork|7 months ago
[deleted]
oc1|7 months ago
[deleted]
A4ET8a8uTh0_v2|7 months ago
nawgz|7 months ago
It's intellectually exciting.
On the flip side, capitalistic / private / special interests both controlling the progress and having the most ability to utilize it to further centralize power and wealth is deeply concerning. We can already see more controversial figures involved in AI using it to spread their personal viewpoints.
It feels really easy to see how our jobs/labor and therefore our capital and therefore our value in the modern system are being directly attacked by these capabilities and deeply concerning to imagine how further centralization of power could be good for the masses.
hakonjdjohnsen|7 months ago
PaulDavisThe1st|7 months ago
roschdal|7 months ago