Abstract: An actuator subsystem preferably for a robot or bionic linkage. A joint between two robotic or bionic members includes at least first and second actuators such as piston-cylinder assemblies connected between the members. A hydraulic circuit includes a sensor subsystem for sensing the magnitude of the load on the piston-cylinder assemblies and/or members. A fluid supply system includes an actuatable control valve operable to supply fluid to one or both piston-cylinder assemblies. A control circuit is responsive to the sensor and is configured to electronically control the fluid subsystem to supply fluid to the first piston-cylinder assembly when the sensor subsystem senses a load below a predetermined magnitude and to supply fluid to both piston-cylinder assemblies when the sensor subsystem senses a load above the predetermined magnitude.

Abstract: A robot including a robot body, a plurality of wheels on the robot body for propelling the robot body, and an axle for each wheel. Each wheel is configured to alternately attach to an axle at or proximate the center of the wheel for high efficiency mobility on flat terrain and also configured to attach to an axle at a position offset from the center of the wheel for better mobility on rougher terrain.

Abstract: A robot including a robot body, a plurality of wheels on the robot body for propelling the robot body, and an axle for each wheel. Each wheel is configured to alternately attach to an axle at or proximate the center of the wheel for high efficiency mobility on flat terrain and also configured to attach to an axle at a position offset from the center of the wheel for better mobility on rougher terrain.

Abstract: A robot with a body, at least one leg on each side of the body, and a hip connecting the leg to the body. The hip is configured to abduct and adduct the leg. A linkage is configured to rotate the leg along a predetermined path.