Power generating leg

A power generating prosthetic leg, comprising:

• a thigh link configured to be coupled to an above-knee amputee's remaining limb;
• a shank link;
• a knee mechanism connected to said thigh link and said shank link, and
• configured to allow flexion and extension movements of said thigh link and said shank link relative to each other;
• a hydraulic torque generator configured to generate torque between said shank link and said thigh link;
• and
• a power unit configured to operate in both a power utilization mode and a power dissipating mode, said power unit including a first hydraulic path between a fluid reservoir and the hydraulic torque generator having a hydraulic motor rotatably coupled to an electric generator and a motor isolating valve connected in series, and a second hydraulic path between the fluid reservoir and the hydraulic torque generator including an actuated flow restricting valve;
• wherein when said power unit is in a power utilization mode, said motor isolating valve is in an open position and say hydraulic motor is powered by the electric generator and actuates the hydraulic torque generator to create a torque between the thigh link and the shank link;
• and
• wherein when said power unit is in a power dissipation mode, said motor isolating valve is in a closed position and said actuated flow restricting valve restricts fluid flow between the hydraulic torque generator and the fluid reservoir and causes the hydraulic torque generator to resist motion of the thigh link and shank link with respect to one another.

A method of using an artificial leg comprising:

• coupling a power generating leg to a person's lower limb, said power generating leg comprising:
• a thigh link;
• a shank link;
• a knee mechanism connected to said thigh link and said shank link, and configured to allow flexion and extension movements of said thigh link and said shank link relative to each other;
• a hydraulic torque generator configured to generate torque between said shank link and said thigh link;
• and a power unit coupled to said hydraulic torque generator, and configured to cause said hydraulic torque generator to generate torque, the power unit including a fluid reservoir in fluid communication with a hydraulic motor and the hydraulic torque generator;
• and
• operating said power unit in a power regeneration mode, wherein when said power unit is in said power regeneration mode, and hydraulic fluid flows between the hydraulic torque generator and the fluid reservoir to cause the hydraulic motor to turn, a voltage is generated as a function of an angular velocity of the thigh link and shank link relative to each other, said power unit causes said torque generator to generate a torque that opposes the angular velocity of said thigh link and said shank link relative to each other and said power unit converts a portion of the power associated with the product of said torque and said angular velocity of said shank link and thigh link relative to each other into electrical power to be stored in a storage device.