Researchers from Japan have developed a two-legged biohybrid robot inspired by the human gait, combining muscle tissue and artificial materials. Their findings were published on January 26th in the journal Matter.
„Research on biohybrid robots, which represents a fusion of biology and mechanics, has recently attracted attention as a new area of robotics with biological functionality. By using muscles as actuators, we can build a compact robot and achieve efficient, quiet movements with gentle touch.“
– Shoji Takeuchi, corresponding author, University of Tokyo, Japan
The researchers created a biohybrid robot that mimics human gait and operates in water. The robot has a foam buoyant top and weighted legs for underwater stability. Its skeleton is predominantly made of silicone rubber, which can bend and flex to adapt to muscle movements. They then attached strips of lab-grown skeletal muscle tissue to the silicone rubber and each leg.
When the researchers supplied the muscle tissue with electricity, the muscle contracted and lifted the leg. By alternating electric stimulation between the left and right leg every 5 seconds, the biohybrid robot was able to successfully walk at a speed of 5.4 mm/min (0.002 miles per hour). To turn, the researchers repeatedly administered a pulse to the right leg every five seconds, with the left leg acting as an anchor. The robot successfully completed a 90-degree left turn in 62 seconds.
The team’s future plans include adding joints and thicker muscle tissue to enable more sophisticated and powerful movements. However, according to Takeuchi, before upgrading the robot with additional biological components, the team must integrate a nutrient supply system to sustain living tissues and device structures that allow the robot to operate in the air.
„While celebrating our regular lab meeting, cheers erupted as we watched the video of the robot walking successfully,“ says Takeuchi. „Although they may seem like small steps, they are actually significant advancements for biohybrid robots.“
This work was supported by the JST-Mirai Program, JST Fusion Oriented Research for Disruptive Science and Technology, and the Japan Society for the Promotion of Science.
Kinjo, R., et al. (2024). Biohybrid two-legged robot powered by skeletal muscle tissue. Matter. doi.org/10.1016/j.matt.2023.12.035.