Many of us have seen impressive videos of humanoid robots that walk, talk, and even seem to think like people. But can they do anything and replace human workers? Can they run faster even than greyhounds or jump higher than pumas?
Robotics engineers have worked for decades and invested millions of research dollars trying to create a robot that can walk or run like an animal. Yet, many animals are capable of feats that would be impossible for robots today.
Animals are much better at running than robots. The difference in performance arises in the important dimensions of agility, range, and robustness.
“A wildebeest – an African member of the antelope family that resembles a cow – can migrate for thousands of kilometers over rough terrain; cockroaches can lose a leg but still run fast; and a mountain goat can climb up a cliff,” said Prof. Max Donelan of Simon Fraser University’s biomedical physiology and kinesiology department in British Columbia. “We have no robots capable of anything like this.”
He and colleagues at the University of Washington, the University of Colorado at Boulder, and the Georgia Institute of Technology have just published a study in the journal Science Robotics titled “Why animals can outrun robots.”
To answer why and how robots lag behind animals, they investigated various aspects of running robots and compared them with their equivalents in animals for a paper published in Science Robotics. The paper finds that, by the metrics engineers use, biological components performed surprisingly poorly compared to fabricated parts. Where animals excel, however, is in their integration and control of those components.
To figure out how can move like animals
The researchers each studied one of five different “subsystems” that combine to create a running robot – power, frame, actuation, sensing, and control – and compared them with their biological equivalents. Until now, it has been commonly accepted that animals’ outperformance of robots is due to the superiority of biological components.
“The way things turned out is that, with only minor exceptions, the engineering subsystems outperformed the biological equivalents—and sometimes radically outperformed them,” the authors wrote. But also, what’s very, very clear is that, if you compare animals to robots at the whole system level, in terms of movement, animals are amazing—and robots have yet to catch up.”
Optimistically, for the field of robotics, the researchers noted that if you compare the relatively short time that robotics has had to develop its technology with the countless generations of animals that have evolved over many millions of years, the progress has been remarkably quick.
“It will move faster because evolution is undirected,” they added. “While we can easily correct how we design robots and learn something in one robot and download it into every other robot, biology doesn’t have that option o there are ways that we can move much more quickly when we engineer robots than we can through evolution – but evolution has a massive head start.”
More than simply an engineering challenge, practical running robots offer countless potential uses. Whether solving ‘last mile’ delivery challenges in a world designed for humans that is often difficult to navigate for wheeled robots, carrying out searches in dangerous environments, or handling hazardous materials, the technology has many potential applications.
The researchers hope their study will help direct future development in robot technology, with an emphasis not on building a better piece of hardware but on understanding how to integrate and control existing hardware. Donelan concluded that “as engineering learns integration principles from biology, running robots will become as efficient, agile, and robust as their biological counterparts.”
Dr. Sarah Adams is a scientist and science communicator who makes complex topics accessible to all. Her articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.
