Quadrupedal or four-legged robots exhibit quadrupedal motion. They benefit from increased stability over bipedal robots, especially during movement. At slow speeds, a quadrupedal robot may move only one leg at a time, ensuring a stable tripod. Four-legged robots also benefit from a lower center of gravity than two-legged systems.
Four-legged robots include:
- The TITAN series developed since the 1980s by the Hirose-Yoneda Laboratory.
- The dynamically stable BigDog, developed in 2005 by Boston Dynamics, NASA's Jet Propulsion Laboratory, and the Harvard University Concord Field Station.
- BigDog's successor, the LS3.