Simulation of a 2D hopper using SLIP model and Raibert style controller.
[1]. M. Raibert, M. Chepponis and H. Brown, "Running on four legs as though they were one," in IEEE Journal on Robotics and Automation, vol. 2, no. 2, pp. 70-82, June 1986, doi: 10.1109/JRA.1986.1087044.