Here is a soft legged robot that works without electronic components. Made by UC San Diego Bioinspired Robotics and Design Lab researchers, this robot is controlled and powered by pressurized air. Its gait is inspired by African sideneck turtles.
As the researchers explain, they designed
soft valves and pneumatic circuits to control the walking direction of the robot, used a soft ring oscillator circuit to generate the rhythmic oscillatory movement similar to central pattern generator circuits observed in nature.
The robot has sensors to change its gait to respond to its environment. The above video shows it in action.