We have built a series of legged robots for experiments on active balance in dynamic legged locomotion. Taken collectively, these robots have traversed simple paths, run with several different gaits (hop, run, trot, pace, bound), run fast (13 mph), jumped over obstacles, controlled step length, climbed a simplified stairway, and performed rudimentary gymnastic maneuvers. Although no one robot performed all these tasks, the machines all use a common set of balance and control principles.
Spring Flamingo (1996-): Used to study planar bipedal walking. First Leg Lab robot to use feet and active ankles.
Spring Turkey (1994-1996): Used to study planar bipedal walking.
Geekbot (1994-1995): Used to study the smooth transfer of support, from one foot to the other, during dynamic rocking.
Planar One-Leg Hopper (1980-1982). The first Leg Lab robot. It has just one leg with a small foot. It was designed to explore active balance and dynamic stability in legged locomotion. It was controlled with a simple three-part algorithm. The Planar Hopper is shown here jumping over a stack of blocks.
3D One-Leg Hopper (1983-1984): Built to show that activly balanced dynamic locomotion could be accomplished with simple control algorithms. It hopped in place, traveled at a specified rate, followed simple paths, and maintained balance when disturbed.
Planar Biped (1985-1990): Used to show that one-legged control algorithms ccould be generalized for two-legged running, provided just one leg was used at a time. We have used the planar biped to study locomotion on rough terrain, running at high speed, and gymnastic maneuvers.
Quadruped (1984-1987): Demonstrated that two-legged running algorithms could be generalized to allow four-legged running, including the trot, pace, and bound.
Monopod (1988-1989): Used to investigate simple articulated legs with rotary joints and a springy foot.
Uniroo (1991-1993): The first Leg Lab robot patterned loosely after an animal. It has an articulated leg with the same link length proportions as a kanagaroo and it has a simple actuated tail.
3D Biped (1989-1995): Hops, runs, and performs tucked somersaults.
Planar Quadruped (1995-1996): An experimental platform for studying the role of an articulated spine in running.
Passive Dynamic Doll (1993-1994): Performs layout somersaults about the unstable middle principal axis of inertia with stability provided by passive arm motion.
Zero Gravity Robot (1988): Designed to suggest how one could run in space, if you had a ceiling in addition to a floor. It bounces between two walls in a plane while floating on an air table.