Compared to robots, the human body is flexible, capable of fine movements, and can efficiently convert energy into movement. Japanese researchers took inspiration from human walking and combined muscle tissue with artificial materials to create a biohybrid robot that moves on two legs. Published in the journal on January 26th problemThis method allows the robot to walk and turn.
Corresponding author Professor Shoji Takeuchi of the University of Tokyo, Japan, said, “Research on biohybrid robots that combine biology and mechanics has recently been attracting attention as a new field of robotics with biological functions.” “Using muscles as actuators allows us to build small robots and achieve efficient, quiet movements with a gentle touch.”
The innovative bipedal robot developed by the research team was built on the legacy of biohybrid robots that utilize muscles. Muscle tissue drives the biohybrid robot to crawl straight forward, swim, and change direction, but not sharply. However, pivoting and making sharp turns are essential functions for robots to avoid obstacles.
To create more agile robots with fine and delicate movements, researchers designed a biohybrid robot that mimics human walking and operates in water. The robot has a foam buoy top and weighted legs so it can stand upright underwater. The robot's skeleton is primarily made of silicone rubber, which can flex and flex with muscle movement. The researchers then attached lab-grown pieces of skeletal muscle tissue to each leg with silicone rubber.
When the researchers bombarded the muscle tissue with electricity, the muscles contracted and the legs moved up. As the electricity dissipated, the heel of my leg landed forward. By alternating electrical stimulation between the left and right legs every five seconds, the biohybrid robot successfully “walked” at a speed of 5.4 mm/min (0.002 mph). To make the rotation, the researchers gave the right leg repeated rapid strikes every five seconds while the left leg acted as an anchor. The robot successfully made a 90-degree left turn in 62 seconds. Studies have shown that muscle-powered bipedal robots can walk, stop, and make fine-tuned rotational movements.
“Currently, we apply electric fields to the legs individually by manually moving a pair of electrodes, which takes time,” Takeuchi said. “In the future, we expect to be able to increase the speed even more efficiently by integrating electrodes into robots.”
The research team also plans to give the biped robot joints and thicker muscle tissue to enable more precise and powerful movements. But Takeuchi said that before the robot can be upgraded with more biological components, it must incorporate biological tissue that would allow the robot to operate in the air, as well as a nutrient supply system to maintain the structure of the device.
“At a regular lab meeting, there was a lot of cheering when we saw the robot successfully walk on the video,” Takeuchi said. “It may seem like a small step, but it’s actually a giant leap for biohybrid robots.”
This work was supported by the JST-Mirai Program, JST Convergence-Oriented Research for Disruptive Science and Technology, and the Japan Society for the Promotion of Science.