Why humanoid robots?

In this post, we explore why we build machines that look like us

Humanoid robots have captivated our collective imagination for over a century. In science fiction films, they are sometimes portrayed as attaching, like C-3PO from Star Wars, cold and calculating as Data in Star Trek, but more often, they inspire fear. In The Terminator, Skynet, an artificial intelligence, seeks to eradicate humanity, dispatching the T-800, a menacing humanoid robot, to assassinate Sarah Connor, the future mother of the resistance leader. In I, Robot, loosely adapted from Isaac Asimov’s short story collection of the same name, robots spiral out of control even though they are supposed to be governed by the Three Laws of Robotics. Their interpretation of 'protecting humanity' leads to an authoritarian takeover, pitting them against the very people they were designed to serve. Ex Machina presents a subtler yet equally chilling cautionary tale. This modern exploration of artificial intelligence features an android who manipulates the protagonist, ultimately escaping confinement by killing its creator.

Given these dire scenarios, why do we persist in developing humanoid robots? Several compelling reasons explain this pursuit.

1. The human form is versatile

Most robots in use today are aimed at a single application: they do one thing well, but they do one thing only. We call this kind of robots application-specific. Humanoid robots are a different category of robots, they are general-purpose. It means they are extremely versatile and can tackle a wide range of activities, even if they don’t excel at any one in particular.

In an interview with Lex Fridman, Robert Playter, CEO of Boston Dynamics, captured this trade-off: “This is the curse of a general purpose robot, that they’re not perfect at any one thing. But they might be able to do a wide variety of things. And that is the goal at the end of the day.” Playter emphasized that while specialized machines can perform specific tasks exceptionally well in controlled environments, general-purpose robots, like humanoids, must handle the uncertainty and variability of the real world, which is far more challenging.

Consider a washing machine, which is perfectly designed to clean your clothes efficiently. In a few years, a humanoid robot might also be able to wash your clothes, though likely not as effectively as a dedicated washing machine. However, the humanoid could go further, it could retrieve the clothes from the laundry basket, load them into the machine, and later fold them and place them back in your closet, handling a broader sequence of tasks. Now, ask your washing machine to help with gardening. I think you get the point. This comparison reveals the often-underestimated potential of the humanoid form. All things considered, we can acknowledge that the world around us has been shaped by us humans, relying solely on our minds, our hands, our ability to move and communicate. It is remarkable.

Could we design a machine even more versatile than the humanoid robot, such as a robot with three or four arms? It’s possible, but as we will see, the human form offers a number of other advantages that make it particularly well-suited for practical and widespread adoption.

2. Our world is made by humans for humans

Our environment is built by humans, for humans. We have shaped the world at our own image. The modern world fits our human form, making it naturally compatible with humanoid robots. In a way, the humanoid form is the universal USB connector of the physical world. Our entire infrastructure, from homes and offices to hospitals and public transportation, is crafted for users who look and move like us. Car seats are contoured to support human legs and backs, with pedals positioned for human feet. Doorknobs require a hand with an opposable thumb to twist them. Light switches sit at a height reachable by an average adult arm. Even a coffee mug’s handle assumes you have fingers to grip it. These design choices reflect a world molded for human bodies.

More precisely, the world is optimized for the average-sized adult. If you’re still a child or rely on a wheelchair, navigating this world can still be a challenge. Step into any building, and you’ll see it: doors stand about six feet tall, stair steps rise seven to eight inches, and chairs accommodate someone between five and six feet in height.

The tools and machines that we use daily are all built to be operated by human hands. Simple tasks like turning a screwdriver or wielding a hammer rely on our manual dexterity, and more advanced tasks like using a computer with its keyboards and mouse demand fingers to type and click. Consider something as basic as reading a book: its size, weight, and the act of turning pages are all intuitive for human hands and eyes, but would be cumbersome for a non-humanoid form.

The humanoid robot is perfectly adapted to our world. It can step into any environments and interact with these tools without requiring an overhaul of the world around it.

3. Changing our world for other machines is much harder

Designing humanoid robots is challenging, but redesigning the entire world to accommodate a different kind of robot is a completely different ball game.

Have we ever reshaped the world for a machine before? Yes, we did. We changed our world for the automobile. Cities and landscapes were transformed with roads, parking lots, highways, and gas stations, fundamentally altering how we live and move. This overhaul fundamentally altered how we live, travel, and interact with our surroundings, giving rise to suburbs and redefining urban planning. However, this transformation came at a tremendous cost, requiring decades of investment, immense resources, and significant societal adaptation.

Redesigning the world for a non-humanoid general-purpose robot: whether it’s a multi-legged machine, a rolling drone, or a completely novel form, would demand a similar, if not greater, effort. In contrast, humanoid robots can operate within the infrastructure we have already built for ourselves, making their deployment a far more practical endeavour.

4. There is abundance of human data

With billions of humans to observe and emulate, it’s theoretically possible to amass a vast amount of data on how humans perform tasks, interact with their environment, and solve problems. The theory is that humanoid robots will be able to benefit from a vast wealth of human data, making their training and development more effective.

In a CNBC interview on March 20, 2024, Nvidia CEO Jensen Huang highlighted this advantage when asked by Jim Cramer, “Why do robots look like people?” Huang responded, “Robots look like people because… a couple of reasons. The first reason, and the most important reason, is that we built the world for ourselves, and so the workstations of a factory, the manufacturing line of a factory, was really created for people. And that’s the most important reason. The second most important reason is that we have to teach a robot how to be a productive robot, and you need data for that. We’re in a world where, in order to write software for a computer, we use data, or training examples, and the computer learns from the examples. Well, we have the most examples of humans moving around as just about any other form of data.”

Huang echoed the argument that our world is designed for human bodies, but he also introduced a critical second point: the pivotal role that data will play in developing true embodied AI. This is a strong argument in favour of humanoid robot, in particular as humanoids will have to learn from humans to be able to replace them in the most annoying and hazardous tasks.

5. A gradual transition

Humanoid robots have another advantage compared to other general-purpose robots: they can integrate into human environments with minimal friction. Unlike a disruptive, all-at-once overhaul, humanoids can step into roles performed by humans at a pace that suits the organization, significantly reducing the risks associated with deployment. This approach enables companies to move at their own pace, they can adapt to the technology incrementally, and build confidence in their ability to manage them.

Imagine a team of four workers on a production line: a humanoid robot can initially replace a single worker who is absent due to illness, maintaining productivity without overhauling the team dynamic. Over time, as trust in the technology grows, additional humanoids can be introduced to address labor shortages, particularly for undesirable shifts. In factories operating on a 3x8 schedule, i.e. three eight-hour shifts around the clock, finding workers willing to take night shifts is often a challenge. Humanoid robots can fill these gaps, ensuring continuous operation while reducing the strain on human employees.

Another key benefit of this gradual transition is the opportunity for humanoids to learn and improve alongside humans. By working in human environments, these robots can gather real-time data on workflows, interactions, and tasks, which can be used to refine their performance with over-the-air updates.

6. A cost-effective transition

Cost is a critical consideration in any robotics deployment, and humanoid robots offer a significant advantage in terms of infrastructure expenses compared to other robot designs. Specialized robots, such as claw-based machines or wheeled bots, often require extensive environmental modifications to function effectively.

In contrast, humanoids can operate in spaces already built for humans, minimizing the need for costly retrofitting. This low infrastructure cost makes humanoid robots an economically viable option for widespread adoption.

However, it’s crucial to understand that humanoids are not intended to replace other types of robots, nor do they compete with specialized machines like robotic arms or automated guided vehicles. Instead, their primary role is to fill roles where human labor is scarce or unavailable, particularly in industries and roles facing acute labor shortages.

7. Humans can replace humanoids

Humanoid robots will maintain a symbiotic relationship with humans: by working alongside them, they ensure that people remain engaged in physical tasks and retain essential skills in case the robots become unavailable. In a world increasingly reliant on automation, there’s a risk that humans might lose proficiency in manual labor or practical skills if robots take over entirely.

However, the humanoid form factor allows for a balanced approach where humans and robots can share responsibilities. For example, in a warehouse setting, human workers might collaborate with humanoid robots to handle inventory, with robots managing repetitive tasks like lifting heavy boxes while humans oversee quality control or troubleshoot unexpected issues. If a robot malfunctions or a power outage renders it inoperable, human workers can step in seamlessly, using the same tools and workflows, because they’ve stayed actively involved in the process.

This interchangeability not only mitigates the risk of over-reliance on technology but also preserves human expertise in physical work. By fostering this collaborative dynamic, humanoid robots help ensure that humans remain capable and relevant, ready to adapt to any disruptions in robotic assistance.

8. Humans can teleport into humanoids

Humanoid robots offer a unique advantage by serving as avatars for humans, effectively allowing people to “teleport” into them through remote operation or telepresence. This future technology will enable humans to project their presence into distant or dangerous environments, controlling a humanoid as if they were physically there.

A humanoid robot equipped with advanced sensors, high-resolution cameras, and haptic feedback could be operated by a human wearing a VR headset and motion-capture suit. This setup will allow the operator to see through the robot’s eyes, move its limbs in real time, and even feel tactile sensations, like the resistance of grasping an object, creating an immersive experience of embodiment from afar.

This concept was explored in the 2009 science fiction movie Surrogates, starring Bruce Willis. In this film, humans use humanoid robots as surrogates to live their lives remotely, engaging in everything from daily routines to more indulgent or risky behaviors, all while their real bodies remain safe at home. While the movie portrays this technology being used for escapism and vice, real-world applications of remote-controlled humanoids will be far more practical and impactful, especially in high-risk scenarios. For example, a humanoid robot could be deployed in a contaminated nuclear facility or a chemically hazardous site, allowing a human operator to perform critical tasks, like repairing equipment or sealing a leak, without exposure to life-threatening conditions.

The ability to “teleport” into humanoids will be transformative in a number of fields. This capability will not only enhance safety but also extend human reach, opening up new possibilities for exploration, intervention, and innovation.

9. Humans know how to interact with humanoids

Humans are inherently skilled at collaborating with human beings, and therefore other humanoids. Our social instincts enable us to interpret body language, anticipate movements, and coordinate effortlessly with others who share our form. A humanoid robot benefits from this familiarity, its human-like shape allows us to interact with it intuitively, without needing to learn new protocols. In a factory, a worker can hand a tool to a humanoid as they would a colleague, or guide it through a task with gestures and verbal cues.

This natural compatibility accelerates training by reducing the learning curve, making humanoids uniquely suited to integrate into our social and professional lives.

Changing the world without changing it

The impact of humanoid robots on the world will be profound, it will revolutionize industries and it will address critical societal challenges. It will change the world.

Yet, it is interesting to realize that they will achieve this without requiring a fundamental redesign of the world around them. By fitting seamlessly into our environments, using the same tools, and navigating the same spaces as we do, humanoid robots will change the world while leaving its physical infrastructure unchanged.