Boston Dynamics: How the Dancing Robots Were Made

A Machine That Does a Backflip

When a video of a humanoid robot leaping onto a box, landing on two legs, and then turning a full backward somersault to stop precisely on its feet swept the internet in late 2017, the first feeling many people had was a strange mix of wonder and unease. That backflip was not a simple stunt mimicking a gymnast's move but a kind of declaration: that a machine had become able to compute and control its own center of mass and rotational inertia in real time. And the company that made that declaration was Boston Dynamics.

Yet to those who had long followed this company, the video was not a sudden event but the natural conclusion of a single question pursued over decades. How can a machine move roughly, like an animal or a person, without losing its balance? That question began in a university lab in the 1980s, passed through a military pack-mule robot and a disaster-response robot, weathered a turbulent series of acquisitions that changed its owner three times, and finally arrived at the electric-drive humanoid walking into car factories today. This article follows that long journey from its very beginning to the very latest.

Starting from the Science of Legs

At the starting point of this story stands an engineer named Marc Raibert. In the 1980s, at Carnegie Mellon University and then at the Massachusetts Institute of Technology (MIT), he led a lab called the Leg Laboratory and devoted himself to a topic that seemed odd at the time: how to make machines that move on legs rather than wheels run while keeping their balance. The one-legged, two-legged, and four-legged robots built in his lab hopped, ran, and turned somersaults, and in the process he laid the scientific foundation for dynamic balance, the control that recovers stability by moving continuously rather than coming to a halt to find it.

In 1992, Raibert took this research out of the university and founded Boston Dynamics as an MIT spin-off. What is interesting is that the early company was quite different from the robot company we picture today; for a time it earned its money making human-motion simulation software for the military and corporations, and it began building physical robots in earnest only later. Yet the philosophy at the company's root was clear from the start: a robot should not be an industrial arm repeating preset motions but a being that, like an animal, balances itself as it moves over the unpredictable terrain of the real world.

Machines That Resembled the Wild

This belief first left a powerful impression on the world in the mid-2000s, through BigDog, developed with funding from the U.S. Defense Advanced Research Projects Agency (DARPA). Built to be a military pack mule that could carry heavy loads and follow soldiers across rough mountain terrain, this four-legged robot recovered its posture without falling even as it slipped on snow, and regained its balance after staggering when kicked from the side, evoking an uncanny familiarity, as if one were watching a living beast.

Around BigDog, the company poured out a series of experiments that sought to reproduce the athletic ability of wild animals in machines. Cheetah, which sprinted on a treadmill at tens of kilometers per hour and broke speed records for legged robots, and PETMAN, which took human form and walked and crouched to test the chemical-protection performance of hazmat suits, are such examples. Most robots of this era were research demonstrations rather than commercial products, but through them Boston Dynamics raised its own domain, dynamic balance in rough environments, to a level few could follow, while building a distinctive culture of leaving a deep impression on the public through video.

Atlas Stands on Two Legs

Carrying the science of balance built on four legs over to two legs was a far harder challenge, and the crystallization of that challenge was Atlas, the humanoid robot unveiled in 2013 for DARPA's Robotics Challenge (DRC). Under the goal of building a robot that could close valves, clear debris, and drive vehicles at disaster sites no human could enter, as the Fukushima nuclear accident had shown, the early Atlas was a hydraulically driven machine, powerful but heavy and rough.

This hydraulic Atlas was at first a ponderous machine that moved slowly while trailing a tangle of cables, but in Boston Dynamics' hands it gained astonishing agility year after year. It walked across uneven rock fields, balanced on one foot, and eventually reached the stage of jumping onto a box and turning a backflip; what Boston Dynamics showed in this process was not merely the power of hardware but the depth of whole-body control that coordinates every joint at once to produce dynamic movement.

Atlas was a purely research robot, of which not a single unit was ever sold commercially. Even so, the reason this robot matters is that almost every company that has entered this market, from Tesla's Optimus to China's many humanoids, takes as its starting point, whether consciously or not, the baseline of motion that Atlas demonstrated first. Atlas was never sold, but its videos lit a fire under the imagination of an entire industry.

A Jewel Sold Three Times

Technically the best in the world, Boston Dynamics was for a long time not a company that made money. Because the distance between its dazzling demo videos and products that actually sold was wide, the company walked a peculiar fate, passing successively through the hands of giant corporations that recognized its value. The first owner was Google, which acquired the company in 2013 with ambitions in the robotics business. Amid disagreements over a clear revenue model, however, Google ultimately handed the company to Japan's SoftBank in 2017.

SoftBank, too, bet on the future of robots, but it was the third owner, Korea's Hyundai Motor Group, that grew Boston Dynamics into a real business. Hyundai announced the acquisition in late 2020 and secured a controlling stake at a valuation of about $1.1 billion in 2021, then moved toward effectively full ownership by buying out the stake SoftBank had retained. The paradox that the most iconic American robot company is owned by a Korean automaker was also a scene foreshadowing a new union, where the mass-production capability of cars meets the athletic intelligence of robots.

A Robot That Finally Earns Its Keep

Under Hyundai's capital and business resolve, Boston Dynamics set out in earnest on the long-standing homework of commercialization. Its first fruit was Spot, the four-legged robot that went on sale in June 2020; a descendant of BigDog, this yellow robot dog was sold into the field for dangerous, repetitive inspection work at power plants, construction sites, factories, oil and gas facilities, and mines, and hundreds of units began actually working. Patrolling places that are troublesome or dangerous for people to check one by one, and gathering data, became money before the dazzling backflips did.

The prototype for Spot was the small, agile SpotMini, unveiled earlier; climbing stairs, opening doors, and carrying dishes around the house, this demo robot served as the bridge that erased BigDog's rough military image and showed that Boston Dynamics' technology could enter the sites of everyday life and industry.

After Spot, Boston Dynamics introduced Stretch, a robot aimed at logistics warehouses. With a long, strong arm and a suction gripper mounted on a wheeled base, this robot was designed to automate the monotonous, grueling work of unloading boxes from trucks and stacking them on pallets, and it was adopted at the sites of logistics firms such as DHL, becoming, alongside Spot, the company's near-term revenue stream. The company once called the jewel of the lab had at last begun to take the shape of a business that earns its own keep.

Shedding Hydraulics, Donning Electricity

Then, in April 2024, Boston Dynamics released two videos in succession that announced at once the end of one era and the beginning of another. First it bade farewell with a retirement video gathering the behind-the-scenes moments of the hydraulic Atlas falling and tottering over more than a decade, and the very next day it presented a wholly new, electrically driven Atlas. The scene in which the electric Atlas, lying on the floor, eerily folded its legs up toward its head and sprang upright in a way no human could imitate made it clear that this robot would no longer be confined to mimicking human movement.

The shift from hydraulics to electricity was not a mere swap of parts but a shift in philosophy. As covered in Part 3, hydraulics produce strong force but are heavy, leak oil, and are hard to control precisely, whereas electric drive is lighter, quieter, and can be handled more delicately, making it far better suited to real work sites such as factories. The new electric Atlas was designed with ranges of rotation beyond the human joint, turning its waist a full 360 degrees and bending its limbs freely, surpassing humans in both strength and flexibility. From a robot for dazzling stunts to a robot for real work, the very purpose of Atlas had moved.

Adding Artificial Intelligence to Athletic Intelligence

The next problem the electric Atlas had to solve lay not in the body but in the head, that is, artificial intelligence. However excellent the body, if it cannot judge for itself what to do and how, it remains a machine repeating preset motions, and to address this Boston Dynamics is walking two paths at once. One is the basic research, through the Robotics and AI Institute (RAI Institute) that founder Raibert set up separately in 2022 with Hyundai's funding, to make robots understand the world around them better; the other is the development of a Large Behavior Model carried out with the Toyota Research Institute (TRI) in 2025.

The collaboration with the Toyota Research Institute is especially noteworthy: it is an attempt to train the robot, taking instructions in language, to perform walking and hand-work as long-horizon tasks within a single policy, so that an Atlas trained on countless human demonstrations and the language annotations attached to them can move on its own following general instructions. Indeed, in demonstrations released since late 2024, Atlas was shown autonomously sorting and moving parts as written on a list, in a mock factory environment, without human teleoperation.

And in 2026, all of these currents converged into a single product. Boston Dynamics unveiled the production version of the electric Atlas at CES 2026 in January and began manufacturing it right away at its Boston headquarters; with 56 degrees of freedom and a 50-kilogram lift capacity, the largest customer for this production Atlas was its parent company, Hyundai. Hyundai Motor Group announced plans to deploy more than 25,000 Atlas units across its vehicle manufacturing sites, and the unit cost, about $130,000 to $140,000 in the early mass-production stage, is expected to fall to around $30,000 once cumulative production passes 50,000 units. The core component, the high-powered actuators, is supplied by Hyundai Mobis, showing the automaker group's vertical integration extending into robots.

The Place of the Pioneer, and the Challenge

Boston Dynamics' greatest strength lies in decades of athletic intelligence that few can imitate, the depth of handling a robot's body freely amid rough reality. From BigDog through the hydraulic Atlas to the electric Atlas, this company's hardware and whole-body control remain the industry's baseline, and the addition of the vast real demand of car manufacturing and the vertical integration of the Hyundai group is a solid foundation its rivals do not have.

The challenge, however, is just as clear. As seen in Part 5, Tesla pursues this market with capital and artificial intelligence, and as seen in Part 8, China's various firms chase it with overwhelming volume and price; as the decisive arena of robots gradually shifts from the body to the brain, that is, to artificial intelligence and the cost of mass production, the place of pioneer of athletic intelligence alone may not be enough. Whether the company that stood up on two legs first can become the company that takes the market first depends on how usefully the electric Atlas actually works in Hyundai's factories. The next chapter of the company that built an era of athletic intelligence has only just begun to be written.