Modeling of Inertial Jumping Robots

Jumping robots are traditionally powered by latch-mediated spring actuation (LaMSA), storing energy in a spring and releasing it to jump. This method has allowed robots to use simple mechanisms to jump up to 30m, but is limited by energy density of compliant materials, and requires spring materials to experience high strain. Another energy storage method, inertial energy storage with a flywheel, has also been used for high-power applications, such as satellite launching. This method rotates a mass at high speeds to store energy, then transforms the rotational kinetic energy into linear kinetic energy. Past jumping robots have used this method by transforming energy by braking a flywheel, but this method is inefficient and doesn't scale to high energy systems. We propose an inertial jumping robot that uses a flywheel and transmission to convert rotational kinetic energy into vertical kinetic energy, making the robot jump. We present comprehensive modeling of inertial jumping robot kinematics and dynamics, as well as tradeoffs between parameters such as transmission, flywheel mass, and structural strength. We compare nonlinear transmissions, including a constant force transmission and a minimal torque transmission, showing impacts on jumping loads and performance. Finally, we present modeling of a robot designed to jump over 50m, which would surpass existing jumping robots.