David Hu on How to Walk on Water and Climb Up Walls (Part 2)

Insects walk on water, snakes slither, and fish swim. Animals move with astounding grace, speed, and versatility: how do they do it, and what can we learn from them? In How to Walk on Water and Climb up Walls, David Hu takes readers on an accessible, wondrous journey into the world of animal motion. From basement labs at MIT to the rain forests of Panama, Hu shows how animals have adapted and evolved to traverse their environments, taking advantage of physical laws with results that are startling and ingenious. In turn, the latest discoveries about animal mechanics are inspiring scientists to invent robots and devices that move with similar elegance and efficiency.

In the second part of our Q+A with David Hu, he describes what we know (and don’t know) about animal motion, and what the future of robots will look like. Check out the first part of our Q+A here.

Don’t we already know everything about animal motion?

From cave paintings to today’s videos of cats on YouTube, the movement of animals has always fascinated people. The thesis of my book is that there is an explosion of new interest and progress in understanding animal motion. Recent technological developments and the teamwork of biologists, computer scientists, physicists, and engineers, are leading to changes in the way animal motion is now studied.

What can we learn from studying animal motion?

Animals have existed for millions of years. As a result, they have evolved a huge diversity, inhabiting nearly every part of the planet, across terrains from desert to forest to sea. This range of environments, combined with their intense competition to eat or be eaten has led to the evolution of ingenious methods of locomotion. Their varying locomotion mechanisms can inspire new ways of propulsion for humans, from robots that walk across the clutter in our homes to tracked vehicles that move across the dusty surface of Mars. But before we robots are improved sufficiently to enter our everyday lives, an understanding how animals movement is of great benefit.

What kind of approach is needed to study animal motion?

We already have many of the tools to understand the movement of animals.  Because animals move through air and water, the same tools that engineers use to design boats and airplanes can be applied to animals. The brains of animals can be studied in a similar way. To react quickly to their surroundings, animals rely on a system of nerves that can act autonomously, similar to the cruise control in your car, and the motion of an autonomous robot. Since animals share things in common with boats, airplanes, and robots—the same tools to study these human-made systems can be used to reverse-engineer systems in nature.

How did you become interested in studying animals and insects?

My PhD was on the physics of insects that walk on water. People who study the motion of fluids have often looked to birds and fish for inspiration. During my PhD, I realized that while we often see insects as annoying, they are the dominant non-microscopic life form on earth, and their small size gives them an even greater versatility to move. After my PhD study on water striders and a postdoctoral study on snakes, I founded my own laboratory for studying animal movement.

What are the applications of your work, whether it’s a shaking wet dog or animals waving their tails?

In the course of my work, I often design and build new devices based on animal movement. My work on water striders led to a collaborator building a palm-sized water-walking robot. My work on cat tongues led to a cat-tongue inspired brush that combs with lower force and is easier to clean. From this book, I hope to show curiosity-based research on animal motion can lead to useful new inventions.

What are the robots of the future going to be like?

Many robots rely on wheels and are tested on linoleum floors. Robots built for such structured environments often do poorly in nature. A grassy field, a moss-covered stream, even a living room littered with children’s toys. These are terrain that is impassible by most robots. To traverse these cluttered areas, robots will likely need multiple legs, or no legs at all, resembling insects or snakes. I bet that robots that successfully traverse outdoor environments will show some resemblance to the animals that make this place their home. This is because the laws of physics provide immutable constraints that have influenced the shape and kind of motion that is most effective on these terrain.

David L. Hu is associate professor of mechanical engineering and biology and adjunct professor of physics at Georgia Institute of Technology. He lives in Atlanta.

Adrienne Mayor on Gods and Robots

Adrienne Mayor Gods and Robots coverThe first robot to walk the earth was a bronze giant called Talos. This wondrous machine was created not by MIT Robotics Lab, but by Hephaestus, the Greek god of invention. More than 2,500 years ago, long before medieval automata, and centuries before technology made self-moving devices possible, Greek mythology was exploring ideas about creating artificial life—and grappling with still-unresolved ethical concerns about biotechne, “life through craft.” In the compelling, richly illustrated Gods and Robots, Adrienne Mayor tells the fascinating story of how ancient Greek, Roman, Indian, and Chinese myths envisioned artificial life, automata, self-moving devices, and human enhancements—and how these visions relate to and reflect the ancient invention of real animated machines.

Mayor answered some questions for us about robots, mythology, and her research.

Who first imagined the concept of robots? 

Most historians of science trace the first automatons to the Middle Ages. But I wondered, Was it possible that that ideas about creating artificial life were thinkable long before technology made such enterprises possible? Remarkably, as early as the time of Homer, ancient Greek myths were envisioning how to imitate, augment, and surpass nature, by means of bio-techne, “life through craft”—what we now call biotechnology. Beings described as fabricated, “made, not born,” appeared in myths about Jason and the Argonauts, the sorceress Medea, the bronze robot Talos, the ingenious craftsman Daedalus, the fire-bringer Prometheus, and Pandora, the female android created by Hephaestus, god of invention. These vivid stories were ancient thought experiments set in an alternate world where technology was marvelously advanced.

What makes these ancient stories so compelling today?

Time-traveling back into the past more than two millennia to study what are essentially some of the first-ever science fiction stories by a pre-industrial society may seem strange. But I think the sophistication and relevance of these ancient dreams of technology might help us understand the timeless link between imagination and science. Some of the imaginary self-propelled devices and lifelike androids in the myths foreshadow some of today’s technological inventions of driverless cars, automated machines, and humanoid automatons. There are even mythic versions of Artificial Intelligence and ancient parallels to the modern “Uncanny Valley” effect—that eerie sensation when people encounter hyper-realistic robots. Notably, some of the doubts about creating artificial life expressed in antiquity anticipate our own practical and ethical dilemmas about AI and playing god by improving on nature. Taken together, the ancient narratives really represent a kind of “Mythology for the Age of Artificial Intelligence.”

Why were these perceptive myths about artificial life overlooked until now?

Historians of science tend to assume that automatons featured in classical myths were simply inert matter brought to life by a fiat or a magical spell, like Adam and Eve and Pygmalion’s ivory statue of Galatea. But many of the self-moving devices and automata described in myths were not merely lifeless things animated by magic or divine command. My book focuses on the myths of androids and automatons visualized as products of technology, designed and constructed with the same materials and methods that human artisans used to make tools, structures, and statues in antiquity, but with awesome results beyond what was technologically possible at the time. Some philosophers of science claim it was impossible in antiquity to imagine technology beyond what already existed, until mechanics was formalized as a discipline. But imagination has always driven innovation. Where science fiction goes, technology often follows. The last chapter of Gods and Robots traces the relationship between classical myths and real historical automata that began to proliferate in the Hellenistic era, when Alexandria in Egypt became the hub of learning and innovation and engineers designed self-moving machines and lifelike animated statues.

Modern sci-fi movies pop up in several chapters. How do they relate to ancient myths?

Some 2,500 years before movies were invented, ancient Greek vase painters illustrated popular stories of the bronze robot warrior Talos, the techno-wizard Medea, and the fembot Pandora dispatched to earth on an evil mission, in ways that seem very “cinematic.” Echoes of those classical myths reverberate in cult films like Metropolis (1927), Frankenstein (1931), Jason and the Argonauts (1963), Blade Runner (1982 and 2017), and recent sci-fi movies and TV shows such as Ex Machina and Westworld.

Movies and myths about imagined technology are cultural dreams. Like contemporary science fiction tales, the myths show how the power of imagination allows humans to ponder how artificial life might be created—if only one possessed sublime technology and genius. We can see “futuristic” thinking in the myths’ automated machines and tools, self-driving chariots, self-navigating ships, metal robots powered by special fluids, and AI servants made of gold and silver. Another similarity to sci-fi tales is that the myths warn about disturbing consequences of creating artificial life.

There are 75 extraordinary illustrations in Gods and Robots. Any ancient images that surprised you?

A small museum in Italy has an amazing Greek vase painted in the fifth century BC. It shows Medea and Jason using a tool to destroy the formidable bronze robot Talos. Here is proof that more than 2,500 years ago, an automaton was not only imagined as a machine with internal workings, but that its destruction required technology. Pandora appears on a magnificent amphora from the same time. The artist portrays Pandora as life-sized doll about to be wound up, standing stiffly with a weird grin. The vase’s decorative border design is made up of Hephaestus’s tools to underscore her constructed nature. Another astonishing find was a group of carved cameos depicting the myth of Prometheus creating the first human beings. Instead of merely molding clay figures, Prometheus is shown using different tools to build the first human starting from the inside out, with the skeleton as the framework.

Have you come across any unexpected legends about automatons?

A little-known legend translated from Sanskrit claims that after his death, Buddha’s bodily remains were guarded by robotic warriors in a secret underground chamber in India.

Is there anything about ancient automatons that you would like to know more about?

It would be fascinating to gather automaton traditions from India, China, and Japan, to compare Eastern and Western perspectives on artificial life, AI, and robots.

Adrienne Mayor is the author, most recently, of The Amazons: Lives and Legends of Warrior Women across the Ancient World and The Poison King: The Life and Legend of Mithradates, Rome’s Deadliest Enemy, which was a finalist for the National Book Award (both Princeton). She is a research scholar in classics and the history of science at Stanford University and lives in Palo Alto, California.