MIT Mini Cheetah

MIT Biomimetic Robotics Lab's small quadruped, the first to land a backflip, in 2019.

Mini Cheetah is a small quadruped robot built by MIT's Biomimetic Robotics Lab, led by Sangbae Kim: about 20 pounds, roughly 9 kg, with 12 modular motors, giving each leg 2 hip degrees of freedom plus 1 knee joint. In 2019 it became the first quadruped robot to perform a backflip. Its biggest influence has been in actuator design: pairing a high torque-density motor with a low-reduction-ratio planetary gearbox, called quasi-direct drive, lets it absorb impacts while still being backdrivable and able to estimate torque from motor current. This “MIT Cheetah actuator,” along with its accompanying MIT-mode motor command style, was later adopted by many manufacturers, including Unitree. The team also lent multiple units to other labs, making it a common early platform for reinforcement-learning locomotion research.

ExampleThe MIT team computed the backflip's motion and per-motor torques offline through trajectory optimization, then had Mini Cheetah execute the backflip on real hardware.

Related

Quadruped Robot · Quasi-Direct Drive · MIT Mini Cheetah Actuator · MIT Mode · Legged Robot · Unitree Robotics

Sources

MIT: Mini cheetah is the first four-legged robot to do a backflip
IEEE Spectrum: How MIT's Mini Cheetah Can Help Accelerate Robotics Research

As of

2019-03