A hybrid power system includes a CVT, an internal combustion engine, an electric motor, a clutch, and a synchronization apparatus. The CVT has a CVT input shaft and a CVT output shaft. The internal combustion engine has an internal combustion engine output shaft and the electric motor has an electric motor shaft. The clutch is provided between the internal combustion engine and the CVT. The synchronization apparatus is provided between the internal combustion engine and the electric motor. The clutch and the synchronization apparatus can be adjusted to connect the internal combustion engine output shaft to the electric motor shaft via the CVT, and connect the internal combustion engine output shaft to the electric motor shaft without the CVT. In an example embodiment, the synchronization apparatus includes a first synchronizer between the internal combustion engine and the CVT, and a second synchronizer between the CVT and the electric motor.

A bicycle transmission allows a bicycle operator to change the radius of a pedal crank's transmission gear as sliding gear segments, radially arranged on a base ring assembly, vary their relative radial position from the center of the base plate. These gear segments slide in and out to change the effective radius of the gear. Spring biased locking pins engage adjustable control plates as the crank rotates. The locking pins release to make further adjustments to increase or decrease the effective radius. The transmission may also be used as a variable-ratio prime mover for other motive power applications, to transfer power from the wheel to another rotating component. The transfer of power may be via a chain or a belt.

A locomotion subassembly for a biped robot is disclosed. The locomotion subassembly includes several unique energy transfer mechanisms and arrangements for efficiently powering the motion of the robot.

A locomotion subassembly for a biped robot is disclosed. The locomotion subassembly includes several unique energy transfer mechanisms and arrangements for efficiently powering the motion of the robot.

A segmented pulley transmission is provided. A pulley assembly is rotationally mounted on an axle. The pulley assembly includes a core pulley having a first set of mating features on a peripheral surface thereof. A pulley segment set comprises a number of pulley segments slidably mounted in the pulley assembly and arranged in a ring concentric with the core pulley. The pulley segments are individually actuatable out of the pulley assembly into an engaging position and into the pulley assembly into a non-engaging position. The pulley segments have a second set of mating features on an peripheral surface matching the first set of mating features. An endless drive member has corresponding mating features on an inside surface for engaging the first and second sets of mating features of the core pulley and the pulley segments in an engaging position. Contact between the endless drive member and a core pulley defines a contact zone. An actuator actuates the pulley segments between the engaging and non-engaging positions when the pulley segments are outside of the contact zone. One of the key pulley segments in the pulley segment set is a key pulley segment that is positioned relative to the core pulley such that when the key pulley segment is actuated to the engaging position and rotated into the contact zone, the corresponding mating features of the endless drive member engage the first set of mating features of the core pulley and the second set of mating features of the key pulley segment without the introduction of significant slack or tension.