Today I read a paper titled “Lift-off dynamics in a simple jumping robot”
The abstract is:
We study vertical jumping in a simple robot comprising an actuated mass-spring arrangement.
The actuator frequency and phase are systematically varied to find optimal performance.
Optimal jumps occur above and below (but not at) the robot’s resonant frequency $f_0$.
Two distinct jumping modes emerge: a simple jump which is optimal above $f_0$ is achievable with a squat maneuver, and a peculiar stutter jump which is optimal below $f_0$ is generated with a counter-movement.
A simple dynamical model reveals how optimal lift-off results from non-resonant transient dynamics.