University of California San Diego engineers have created a soft quadruped robot that doesn’t require any electronics to work. The robot only needs a constant source of pressurized air to perform all of its available functions, including control systems and locomotion. Researchers on the project say that the work represents a fundamental step towards fully-autonomous electronics-free walking robots.
The device represents a breakthrough in low-cost robotics applications, including toys and robots that need to operate in environments where electronics can’t function. Areas where normal robots can’t function include areas such as MRI machines or mineshaft. Soft robots are a particularly big field of focus for many researchers because they can be adapted to their environment and can operate safely near humans.
Typical soft robots that are powered by pressurized air are controlled by electronic circuits. The robot developed at UC San Diego is controlled by a light-weight, low-cost system of pneumatic circuits consisting of tubes and soft valves onboard the robot. The robot can walk on command or in response to signals sensed from the environment.
Computational power aboard the bot approximately mimics mammalian reflexes driven by a neural response from the spine rather than the brain. The team found inspiration in neural circuits found in animals called central pattern generators made of very simple elements. Engineers built a system of valves that act as oscillators controlling the order in which pressurized air enters air-powered muscles in the robot’s four legs.
The component that coordinates the robot’s gait delays the injection of air into its legs. The way the robot walks was inspired by sideneck turtles. The bot does have simple mechanical sensors in the form of little soft bubbles filled with fluid at the end of booms that protrude from the robot’s body. When the bubbles are depressed, the robot reverses direction. Researchers designed the robot to feature three valves that act as inverters causing a high-pressure state to spread around the air-powered circuit with the delay in each inverter.
The robot’s legs have three degrees of freedom powered by three muscles and are angled downward at 45 degrees. The team says in the future, they want to improve the robot’s gait allowing it to walk on natural terrain and uneven surfaces.