Prosthetic knee joint, prosthetic knee joint power generating method, and tangible computer-readable storage medium storing program

A prosthetic knee joint power generating method comprising providing the prosthetic knee joint comprising:

• a thigh connection part to be positioned near a thigh part;
• a lower leg part rotatably coupled to the thigh connection part;
• a power generating unit for generating power using a resistance resulting from rotation of the lower leg part relative to the thigh connection part;
• and a fluid circuit through which a working fluid flows, the fluid circuit being configured to generate the resistance, wherein the power generating unit generates power through the flowing of the working fluid, wherein the fluid circuit includes a power-generating-unit control valve for adjusting the resistance by controlling the flowing of the working fluid, wherein the prosthetic knee joint further comprises:
• a control unit for controlling operation of the power-generating-unit control valve, the control unit being configured to operate with the power generated by the power generating unit, wherein the fluid circuit includes:
• a hydraulic cylinder configured to operate with the working fluid;
• and a power generation flow channel connecting together a first port and a second port defined within the hydraulic cylinder and partitioned by a piston movable within the hydraulic cylinder, the power generation flow channel having the power generating unit in a middle thereof, wherein the fluid circuit further includes:
• a first parallel flow channel through which the working fluid flows from the first port to the second port, the first parallel flow channel having a first parallel control valve for adjusting a flow rate of the working fluid;
• and a second parallel flow channel through which the working fluid flows from the second port to the first port, the second parallel flow channel having a second parallel control valve for adjusting a flow rate of the working fluid, wherein the control unit controls the first and second parallel control valves independently, to adjust the flow rate of the working fluid in a flow direction toward the power generating unit,
• wherein the power-generating-unit control valve connected in series to the power generating unit is provided in the power generation flow channel,
• and wherein the first parallel flow channel and the second parallel flow channel are provided in parallel with the power generation flow channel wherein in a case where the working fluid flows from the first port to the second port, when the first parallel control valve is fully opened, the working fluid flows from the first port to the second port through the first parallel flow channel, the working fluid does not flow through the power generation flow channel, and no power is generated in the power generating unit,
• and when an opening of the first parallel control valve is reduced from when the first parallel control valve is fully opened, the flow rate of the working fluid flowing from the first port to the second port through the first parallel flow channel is lowered and the flow rate of the working fluid flowing from the first port to the second port through the power generation flow channel is increased, compared to when the first parallel control valve is fully opened, and the power generating unit resultantly generates power,
• and wherein in a case where the working fluid flows from the second port to the first port, when the second parallel control valve is fully opened, the working fluid flows from the second port to the first port through the second parallel flow channel, the working fluid does not flow through the power generation flow channel, and no power is generated in the power generating unit, and when an opening of the second parallel control valve is reduced from when the second parallel control valve is fully opened, the flow rate of the working fluid flowing from the second port to the first port through the second parallel flow channel is lowered and the flow rate of the working fluid flowing from the second port to the first port through the power generation flow channel is increased, compared to when the second parallel control valve is fully opened, and the power generating unit resultantly generates power;
• wherein the power is generated using the resistance resulting from rotation of the lower leg part relative to the thigh connection part.

A prosthetic knee joint comprising:

• a thigh connection part to be positioned near a thigh part;
• a lower leg part rotatably coupled to the thigh connection part;
• a power generating unit for generating power using a resistance resulting from rotation of the lower leg part relative to the thigh connection part;
• and a fluid circuit through which a working fluid flows, the fluid circuit being configured to generate the resistance,
• wherein the power generating unit generates power through the flowing of the working fluid,
• wherein the fluid circuit includes a power-generating-unit control valve for adjusting the resistance by controlling the flowing of the working fluid,
• wherein the prosthetic knee joint further comprises:
• a control unit for controlling operation of the power-generating-unit control valve, the control unit being configured to operate with the power generated by the power generating unit, wherein the fluid circuit includes:
• a hydraulic cylinder configured to operate with the working fluid;
• and a power generation flow channel connecting together a first port and a second port defined within the hydraulic cylinder and partitioned by a piston movable within the hydraulic cylinder, the power generation flow channel having the power generating unit in a middle thereof, wherein the fluid circuit further includes:
• a first parallel flow channel through which the working fluid flows from the first port to the second port, the first parallel flow channel having a first parallel control valve for adjusting a flow rate of the working fluid;
• and a second parallel flow channel through which the working fluid flows from the second port to the first port, the second parallel flow channel having a second parallel control valve for adjusting a flow rate of the working fluid,
• wherein the control unit controls the first and second parallel control valves independently, to adjust the flow rate of the working fluid in a flow direction toward the power generating unit,
• wherein the power-generating-unit control valve connected in series to the power generating unit is provided in the power generation flow channel, and wherein the first parallel flow channel and the second parallel flow channel are provided in parallel with the power generation flow channel
• wherein in a case where the working fluid flows from the first port to the second port, when the first parallel control valve is fully opened, the working fluid flows from the first port to the second port through the first parallel flow channel, the working fluid does not flow through the power generation flow channel, and no power is generated in the power generating unit,
• and when an opening of the first parallel control valve is reduced from when the first parallel control valve is fully opened, the flow rate of the working fluid flowing from the first port to the second port through the first parallel flow channel is lowered and the flow rate of the working fluid flowing from the first port to the second port through the power generation flow channel is increased, compared to when the first parallel control valve is fully opened, and the power generating unit resultantly generates power,
• and wherein in a case where the working fluid flows from the second port to the first port, when the second parallel control valve is fully opened, the working fluid flows from the second port to the first port through the second parallel flow channel, the working fluid does not flow through the power generation flow channel, and no power is generated in the power generating unit,
• and when an opening of the second parallel control valve is reduced from when the second parallel control valve is fully opened, the flow rate of the working fluid flowing from the second port to the first port through the second parallel flow channel is lowered and the flow rate of the working fluid flowing from the second port to the first port through the power generation flow channel is increased, compared to when the second parallel control valve is fully opened, and the power generating unit resultantly generates power and
• a tangible non-transitory computer-readable storage medium storing a program for generating the power, in the prosthetic knee joint while causing the control unit to control a value of the resistance resulting from rotation of the lower leg part relative to the thigh connection part.