- Mark Rybert, a roboticist and CEO of Boston Dynamics, discusses the development of legged robots and his early inspiration for robotics.
- He was inspired by a conference on legged locomotion and saw the need for robots to move more dynamically and aggressively, leading to the development of hopping robots.
- He emphasizes the importance of natural movement and the need to break out of the cautious and safe approach to robot manipulation.
- His early interest in building and robotics was influenced by his father's passion for engineering and his exposure to tools and electronics at a young age.

- Mark Waber discusses the development of the first hopping robot at the Leg Lab at MIT and Carnegie Mellon
- The project was initially funded by Ivan Sutherland, and later received funding from DARPA
- The technical challenges of creating a hopping robot included actuation, balancing, and controlling the robot in 3D
- The robot's balancing was achieved through energy management, foot placement, and maintaining an upright attitude
- The development of the robot did not initially foresee practical applications, but focused on fundamental research in legged locomotion

- The speaker discusses the early days of Boston Dynamics and the development of legged robots
- They talk about the doubts and challenges faced in creating humanoid robots
- The speaker also mentions the transition from being a simulation company to a robotics company
- They reflect on the development of surgical simulators and the decision to pivot back to building robots
- The first robot built under Boston Dynamics was the AIBO runner, created in collaboration with Sony

- Boston Dynamics transitioned from a simulation company to a robotics company
- They built a fast-moving quadruped robot called Big Dog
- Big Dog led to the development of LS3, a robot that could carry 400 pounds
- LS3 eventually evolved into Spot, a smaller, all-electric robot
- The transition from hydraulic to electric power presented technical challenges
- Boston Dynamics focused on creating natural and beautiful movement in their robots
- They used a dynamic approach and prediction for motion control
- The number of seconds to look ahead for Spot's motion is only a couple

- The speaker discusses the limited horizon approach for calculating movements and obstacles in robotics
- They mention the challenges of sticking a landing and the need for momentum and coordination
- The development of robots capable of somersaults and the importance of understanding human movement through robotics
- The discussion also includes the study of animal locomotion, particularly cheetahs and pronghorns
- The importance of knees in legged robots and the concept of passive dynamics in mechanical systems

- The concept of passive dynamics allows mechanical systems to move without the use of computers or actuators
- Tad McGeer developed a legged system in the 80s that walked down an inclined plane without a computer, using dampers and springs for mechanical action
- The Boston Dynamics AI Institute aims to combine physical and cognitive intelligence in robots
- The institute is working on projects to enable robots to watch, understand, and perform tasks, such as bicycle repair, without explicit models
- The goal is to achieve incremental progress through "stepping stones to moonshots" and improve the reliability and cost of robots
- Success is measured by tangible progress in understanding and translating human actions into robot skills, such as in bicycle repair and navigation.

- The speaker discusses the navigation skills of robots and the potential for machine learning to improve their performance.
- He emphasizes the importance of technical fearlessness, diligence, and fun in building a successful robotics team.
- The speaker also highlights the need for robots to be able to diagnose and fix physical problems in the world.
- He discusses the importance of testing robots in various conditions to ensure their robustness and reliability.
- The speaker also emphasizes the value of simplicity in showcasing robot capabilities through videos.

- Mark Rybert, CEO of Boston Dynamics, discusses the development of legged robots and his early inspiration for robotics
- He emphasizes the importance of natural movement and the need to break out of the cautious and safe approach to robot manipulation
- The development of the first hopping robot at the Leg Lab at MIT and Carnegie Mellon, funded by Ivan Sutherland and DARPA
- The technical challenges of creating a hopping robot included actuation, balancing, and controlling the robot in 3D
- The early days of Boston Dynamics and the development of legged robots, including the transition from being a simulation company to a robotics company
- The development of various robots, such as AIBO runner, Big Dog, LS3, and Spot, with a focus on natural and beautiful movement
- The study of animal locomotion and the importance of knees in legged robots
- The concept of passive dynamics in mechanical systems and the aim of the Boston Dynamics AI Institute to combine physical and cognitive intelligence in robots
- The goal of achieving incremental progress and improving the reliability and cost of robots
- The importance of technical fearlessness, diligence, and fun in building a successful robotics team
- The need for robots to be able to diagnose and fix physical problems in the world, and the value of simplicity in showcasing robot capabilities through videos.

- The speaker emphasizes the importance of being intrepid and having fun in robotics
- They discuss the challenges and failures in creating robots like Atlas and S.P.O.D.
- The speaker highlights the satisfaction of being an engineer and the potential for impact on the world
- They discuss the art and creativity involved in engineering and robotics
- The speaker expresses excitement about the possibility of robots dancing with humans and the potential for collaboration between dancers and robots.

- Sidney Skybetter, a dancer and choreographer, collaborated with computer science professor Stephanie Telex to teach a class where computer science and dance students programmed performances together
- They discussed the challenge of teaching robots to communicate through movement and the difficulty of robots performing alongside famous dancers
- They talked about the importance of finding engineers who love their work and the impact of YouTube on showcasing robotics
- They mentioned Elon Musk's work on a humanoid robot and expressed admiration for his achievements
- They discussed the variety of robots at the AI Institute and their lack of focus on competition in the robotics space

- The speaker discusses their involvement in robotics and the challenges of competition in the AI world
- They mention the potential for quadruped and humanoid robots to become cheaper through mass production and innovation
- The speaker talks about the importance of creating realistic use cases for robotics to make money
- They address the fear of super-intelligent systems and emphasize the balance of opportunities and risks in technology
- The speaker shares the story behind their iconic Hawaiian shirt and the importance of being a contrarian
- They advise young people to consider their passions and interests when choosing a career path

- Mark Rybert gives advice to pursue what you want to do without feeling limited by constraints
- He emphasizes the importance of diligence and pursuing a passion for years
- He discusses the challenges of demonstrating cognitive function in robots
- He believes that flaws and incremental improvement in robots can be compelling and inspiring
- Ultimately, he believes that creating humanoid intelligence systems reflects the specialness of humans
- He suggests that the meaning of life is to have fun and enjoy the short ride
- The conversation ends with a quote from Arthur C. Clarke and a thank you to the audience

- Speaker emphasizes importance of intrepidness and fun in robotics
- Discusses challenges and failures in creating robots like Atlas and S.P.O.D.
- Highlights satisfaction of being an engineer and potential impact on the world
- Discusses art and creativity in engineering and robotics
- Expresses excitement about possibility of robots dancing with humans and collaboration between dancers and robots
- Sidney Skybetter and Stephanie Telex collaborate to teach a class where computer science and dance students program performances together
- Discusses challenge of teaching robots to communicate through movement and difficulty of robots performing alongside famous dancers
- Importance of finding engineers who love their work and impact of YouTube on showcasing robotics
- Mention of Elon Musk's work on humanoid robot and admiration for his achievements
- Variety of robots at the AI Institute and lack of focus on competition in robotics space
- Speaker's involvement in robotics and challenges of competition in AI world
- Potential for quadruped and humanoid robots to become cheaper through mass production and innovation
- Importance of creating realistic use cases for robotics to make money
- Addressing fear of super-intelligent systems and emphasizing balance of opportunities and risks in technology
- Story behind iconic Hawaiian shirt and importance of being a contrarian
- Advice to young people to consider passions and interests when choosing career path
- Mark Rybert advises pursuing passions without feeling limited by constraints
- Emphasizes importance of diligence and pursuing passion for years
- Challenges of demonstrating cognitive function in robots
- Belief that flaws and incremental improvement in robots can be compelling and inspiring
- Creating humanoid intelligence systems reflects specialness of humans
- Suggests that the meaning of life is to have fun and enjoy the short ride
- Conversation ends with a quote from Arthur C. Clarke and a thank you to the audience

Marc Raibert is founder and former long-time CEO of Boston Dynamics, and recently Executive Director of the newly-created Boston Dynamics AI Institute. Please support this podcast by checking out our sponsors:
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TRANSCRIPT:
https://lexfridman.com/marc-raibert-transcript

EPISODE LINKS:
Boston Dynamics AI Institute: https://theaiinstitute.com/
Boston Dynamics YouTube: https://youtube.com/@bostondynamics
Boston Dynamics X: https://x.com/BostonDynamics
Boston Dynamics Instagram: https://instagram.com/bostondynamicsofficial
Boston Dynamics Website: https://bostondynamics.com/

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OUTLINE:
0:00 - Introduction
1:43 - Early robots
6:47 - Legged robots
25:27 - Boston Dynamics
28:45 - BigDog
36:52 - Hydraulic actuation
38:44 - Natural movement
44:31 - Leg Lab
51:23 - AI Institute
54:41 - Athletic intelligence
1:02:35 - Building a team
1:05:37 - Videos
1:13:25 - Engineering
1:16:53 - Dancing robots
1:21:40 - Hiring
1:25:32 - Optimus robot
1:34:02 - Future of robotics
1:38:56 - Advice for young people

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So Big Dog became LS3, which is the big load carrying 1.

Just a quick pause, it can carry 400 pounds.

It was designed to carry 400, but we had it carrying about 1,000 pounds at 1 time.

We had 1 carrying the other 1, we had 2 of them.

So We had 1 carrying the other 1, we had 2 of them.

So 1 of the things that stands out about the robots Boston Dynamics have created is how beautiful the movement is.

How natural the walking is and running is.

So maybe you can talk about what's involved in making it look natural.

Well, I think having good hardware is part of the story and people who think you don't need to innovate hardware anymore are wrong.

The following is a conversation with Mark Rybert, a legendary roboticist, founder, and longtime CEO of Boston Dynamics, and recently the executive director of the newly created Boston Dynamics AI Institute that focuses on research and the cutting edge, on creating future generations of robots that are far better than anything that exists today.

He has been leading the creation of incredible legged robots for over 40 years at CMU, at MIT, the legendary MIT Leg Lab, and then of course Boston Dynamics with amazing robots like Big Dog, Atlas, Spot, and Handle.

This was a big honor and pleasure for me.

To support it, please check out our sponsors in the description.

And now, dear friends, here's Mark Rybert.

When did you first fall in love with robotics?

Well, I was always a builder from a young age.

My father was a frustrated engineer, and by that I mean he wanted to be an aerospace engineer, but his mom from the old country thought that that would be like a grease monkey.

But the result of that was our basement was always full of tools and equipment and electronics.

From a young age I would watch him assembling a kit, an IKO kit or something like that.

I still have a couple of his old IKO kits.

But it was really during graduate school when I followed a professor back from class.

It was Bertolt Horn at MIT, and I was taking an interim class.

And I followed him back to his lab, and on the table was a Vicarm robot arm taken apart in probably a thousand pieces.

And when I saw that, from that day on, I was a roboticist.

1974, so there's just this arm in pieces.

And you saw the pieces and you saw in your vision the arm when it's put back together and the possibilities that holds.

I was in the brain and cognitive sciences department as a graduate student doing neurophysiology.

I'd been an electrical engineer as an undergrad at Northeastern.

And the neurophysiology wasn't really working for me.

I couldn't see really how by looking at single neurons you were going to get to a place where you could understand control systems or thought or anything like that.

And the AI lab was always an appealing – this was before CSAIL, right?

So the AI lab was always an appealing idea, and so when I went back to the AI lab following him, and I saw the arm, I just thought, you know, this is it.

It's so interesting, the tension between the BCS, brain and cognitive science approach to understanding intelligence, and the robotics approach to understanding intelligence.

They have the Center for Brains, Minds, and Machines, which is trying to bridge that gap.

And even when I was there, David Marr was in the AI lab.

David Marr had models of the brain that were appealing both to biologists but also to computer people.

So he was a visitor in the AI lab at the time, and I guess he became full-time there.

So that was the first time a bridge was made between those 2 groups.

Then the bridge kind of went away, and then there was another time in the 80s, and then recently, the last 5 or so years, there's been a stronger connection.

You said you were always kind of a builder.

What stands out to you in memory of a thing you've built?

Maybe a trivial thing that just kind of like inspired you and the possibilities that this direction of

I mean, we were just doing gadgets when we were kids.

I have a friend, we were taking, you know the, I don't know if everybody remembers, but fluorescent lights had this little aluminum cylinder, I can't even remember what it's called now, that you needed a starter, I think it was.

And we would take those apart, fill them with match heads, put a tail on it, and make it into little rockets.

How much was it about function versus just creating something cool?

I think it's still a balance between those 2.

There was a time though when I was, I guess I was probably already a professor or maybe late in graduate school when I thought that function was everything and that mobility, dexterity, perception and intelligence, those are sort of the key functionalities for robotics, that That's what mattered and nothing else mattered.

And I even had kind of this platonic ideal that a robot, if you just looked at a robot and it wasn't doing anything, it would look like a pile of junk, which a lot of my robots looked like in those days.

But then when it started moving, you'd get the idea that it had some kind of life or some kind of interest in its movement.

And I think we purposely even designed the machines, not worrying about the aesthetics of the structure itself.

But then it turns out that the aesthetics of the thing itself add and combine with the lifelike things that the robots can do.

But the heart of it is, you know, making them do things that are interesting.

So 1 of the things that underlies a lot of your work is that the robots you create, the systems you have created for over 40 years now, have a kind of, they're not cautious.

So a lot of robots that people know about move about this world very cautiously, carefully, very afraid of the world.

A lot of the robots you built, especially in the early days, were very aggressive, underactuated.

They're hopping, They're wild, moving quickly.

So is there a philosophy underlying that?

Well, let me tell you about how I got started on legs at all.

When I was still a graduate student, I went to a conference.

It was a biological legged locomotion conference, and I think it was in Philadelphia.

So it was all biomechanics people, researchers who would look at muscle and maybe neurons and things like that.

They weren't so much computational people, but they were more biomechanics.

And maybe there were a thousand people there.

And I went to a talk, 1 of the talks, all the talks were about the body of either animals or people and respiration, things like that.

But 1 talk was by a robotics guy, and he showed a six-legged robot that walked very slowly.

It always had at least 3 feet on the ground, so it worked like a table or a chair with tripod stability.

And I just looked at that and said, wow, that's wrong.

You know, That's not anything like how people and animals work.

Because we bounce and fly, you know, we have to predict what's gonna happen in order to keep our balance when we're taking a running step or something like that.

We use the springiness in our legs, you know, our muscles and our tendons and things like that as part of the story.

So I'm not sure I understood all that when I first saw it, but I definitely got inspired to say, you know, let's try the opposite.

And I didn't have a clue as to how to make a hopping robot work, not balance in 3D.

In fact, when I started, it was all just about the energy of bouncing, and I was gonna have a springy thing in the leg and some actuator so that you could get an energy regime going of balancing.

And the idea that balance was an important part of it didn't come until a little later.

And then I made the one-legged, the pogo stick robots.

Now I think that we need to do that in manipulation.

If you look at robot manipulation, we've been working, we, a community, has been working on it for 50 years.

We're nowhere near human levels of manipulation.

I mean, we can, you know, it's come along.

And I think trying to break out of that safety thing of static grasping, you know, if you look at the, a lot of work that goes on, it's about the geometry of the part, and then you figure out how to move your hand so that you can position it with respect to that, and then you grasp it carefully, and then you move it.

Well, that's not anything like how people and animals work, you know?

We juggle in our hands, we hug multiple objects and can sort them.

So now, to be fair, being more aggressive is gonna mean things aren't gonna work very well for a while.

So it's a longer term approach to the problem.

Maybe that won't pay off, but that's sort of how I'm trying to think about it, trying to encourage our group to go at it.

Well, yeah, I mean, we'll talk about what it means to, what is the actual thing we're trying to optimize for a robot.

Sometimes, especially with human-robot interaction, maybe flaws is a good thing.

Perfection is not necessarily the right thing to be chasing.

Just like you said, maybe being good at fumbling an object, being good at fumbling might be the right thing to optimize versus perfect modeling of the object and perfect movement of the arm to grasp that object, maybe perfection is not supposed to exist in the real world.

I don't know if you know my friend Matt Mason, who is the director of the Robotics Institute at Carnegie Mellon, and we go back to graduate school together.

But he analyzed a movie of Julia Childs doing a cooking thing.

And she did, I think he said something like there were 40 different ways that she handled a thing and none of them was grasping.

She would nudge, roll, flatten with her knife, things like that, and none of them was grasping.

So, okay, let's go back to the early days.

First of all, you've created and led the Leg Lab, the legendary Leg Lab at MIT.

But first of all, the Leg Lab actually started at Carnegie Mellon.

So I was a professor there starting in 1980, about 1986.

And so That's where the first hopping machines were built.

I guess we got the first 1 working in about 1982, something like that.

Then we got a three-dimensional 1 in 1983.

The quadruped that we built at the Leg Lab, the first version, was built in about 1984 or 5 and really only got going about 86 or so.

For people who don't know, I'm talking to Mark Waber, founder of Boston Dynamics, but before that, you were a professor developing some of the most incredible robots for 15 years, and before that, of course, a grad student and all that.

So you've been doing this for a really long time, so you skipped over this, but go to the first hopping robot, there's videos of some of this.

So you talked about the very first step was to get a thing hopping up and down.

And then you realized, well, balancing is a thing you should care about and it's actually a solvable problem.

So can you just go through how to create that robot?

What was involved in creating that robot?

Well, I'm gonna start on the, not the technical side, but the, I guess we could call it the motivational side, or the funding side.

So before Carnegie Mellon, I was actually at JPL, at the Jet Propulsion Lab, for 3 years.

And while I was there, I connected up with Ivan Sutherland, who is sometimes regarded as the father of computer graphics because of work he did both at MIT and then University of Utah and Evans and Sutherland.

Anyway, I got to know him, and at 1 point he said, he encouraged me to do some kind of project at Caltech even though I was at JPL, those are kind of related institutions.

And So I thought about it and I made up a list of 3 possible projects.

And I purposely made the top 1 and the bottom 1 really boring sounding.

And in the middle I put a pogo stick robot.

And when he looked at it, you know, Ivan is a brilliant guy, brilliant engineer, and a real cultivator of people.

He looked at it and knew right away what the thing that was worth doing.

And so he had an endowed chair, So he had about $3,000 that he gave me to build the first model, which I went to the shop and with my own hands kind of made a first model, which didn't work and was just a beginning shot at it.

And in those days, you could just walk into DARPA and walk down the hallway and see who's there.

Ivan, who had been there in his previous life.

And so we walked around and we looked in the offices.

I was basically a kid, but I didn't know this way around.

Craig later became the director of DARPA, but in those days he was the program manager.

And so we went in, I had a little Samsonite suitcase, we opened and it had just the skeleton of this one-legged hopping robot, and we showed it to him.

And you could almost see the drool going down his chin.

I was just about to leave JPL, and I hadn't decided yet where I was going next.

And then when I landed at CMU, he sent $250,000, which in 1980 was a lot of research money.

Did you see the possibility of where this is going?

The balance, I mean, it's legged, it has to do with legged locomotion, I mean, it has to do with all these problems that the human body solves when we're walking, for example.

Yeah, I mean, I think that was the motivation to try and get more at the fundamentals of how animals work.

But the idea that it would result in, you know, machines that were anything like practical, like we're making now.

You know, as an academic, I was mostly just trying to do the next thing, you know, make some progress, impress my colleagues if

So what was, on the technical side, what are some of the challenges of getting up, getting to the point where we saw like in the video, the pogo stick robot that's actually successfully hopping and then eventually doing flips and all this kind of stuff?

Well in the very early days, I needed some better engineering than I had, than I could do myself, and I hired Ben Brown.

We each had our way of contributing to the design, and we came up with a thing that could start to work.

I had some stupid ideas about how the actuation system should work, and we sorted that out.

It wasn't that hard to make it balance once you get the physical machine to be working well enough and have enough control over the degrees of freedom.

And then we very quickly, you know, we started out by having it floating on an inclined air table and then that only gave us like 6 foot of travel.

So once it started working, we switched to a thing that could run around the room on another device.

It's hard to explain these without you seeing them, but you probably know what I'm talking about, a planarizer.

And then the next big step was to make it work in 3D, which that was really the scary part.

With these simple things, you know, people had inverted pendulums at the time for years and they could control them by driving a cart back and forth.

But could you make it work in 3 dimensions while it's bouncing and all that?

But it turned out not to be that hard to do, at least at the level of performance we achieved at the time.

So, okay, you mentioned inverted pendulum, but can you explain how a hopping stick in 3D can control, can balance itself?

You know, The simple story is that there's 3 things going on.

And we had a system that was estimating how high the robot was off the ground.

And using that, there's energy that can be in 3 places in a pogo stick.

1 is in the spring, 1 is in the altitude, and the other is in the velocity.

And so when at the top of the hop, it's all in the height.

And so you could just measure how high you're going and thereby have an idea of a lot about the cycle and you could decide whether to put more energy in or less.

Then there's a part that you decide where to put the foot.

And if you think when you're landing on the ground with respect to the center of mass.

So if you think of a pole vaulter, the key thing the pole vaulter has to do is get its body to the right place when the pole gets stuck.

If they're too far forward, they kind of get thrown backwards.

And what they need to do is get it so that they go mostly up to get over the thing.

And high jumpers is the same kind of thing.

So there's a calculation about where to put the foot, and we did something relatively simple.

And then there's a third part to keep the body at an attitude that's upright.

Because if it gets too far, you know, you could hop and just keep rotating around.

But if it gets too far, then you run out of motion of the joints at the hips.

And we did that by applying a torque between the legs and the body every time the foot's on the ground.

You only can do it while the foot's on the ground.

In the air, you know, the physics don't work out.

How far does it have to tilt before it's too late to be able to balance itself?

Or it's impossible to balance itself, correct itself?

Well, you're asking an interesting question because in those days, we didn't actually optimize things.

And they probably could have gone much further than we did and then had higher performance.

And we just kind of got a sketch of a solution and worked on that.

And then in years since, some people working for us, some people working for others, people came up with all kinds of equations for, or algorithms for how to do a better job, be able to go faster.

1 of my students worked on getting things to go faster.

Another 1 worked on climbing over obstacles.

Because when you're running, it's 1 on the open ground, it's 1 thing.

If you're running like up a stair, you have to adjust where you are, otherwise things don't work out right, you land your foot on the edge of the step.

So there's other degrees of freedom to control if you're getting to more realistic, practical situations.

I think it's really interesting to ask about the early days because believing in yourself, believing that there's something interesting here, and then you mentioned finding somebody else, Ben Brown.

What's that like, finding other people with whom you can build this crazy idea and actually make it work?

Probably the smartest thing I ever did, is to find the other people.

I mean, when I look at it now, you know, I look at Boston Dynamics and all the really excellent engineering there, you know, people who really make stuff work.

So when you talk about pogo stick robot or legged robots, whether it's quadrupeds or humanoid robots, did people doubt that this is possible?

Did you experience a lot of people around you kinda?

they doubted whether it was possible, but I think they thought it was a waste of time.

Oh, it's not even an interesting problem.

I think for a lot of people, people who were, I think it's been both, though.

Some people, I think, I felt like they were saying, oh, why are you wasting your time on this stupid problem?

But then I've been at many things where people have told me it's been an inspiration to go out and attack these harder things.

And I think it has turned out, I think legged locomotion has turned out to be a useful thing.

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Marc Raibert: Boston Dynamics and the Future of Robotics | Lex Fridman Podcast #412