Artificial human limbs and joints employing actuators, springs, and variable-damper elements

Abstract

Biomimetic Hybrid Actuators employed in biologically-inspired musculoskeletal architectures employ an electric motor for supplying positive energy to and storing negative energy from an artificial joint or limb, as well as elastic elements such as springs, and controllable variable damper components, for passively storing and releasing energy and providing adaptive stiffness to accommodate level ground walking as well as movement on stairs and surfaces having different slopes.

1 . An artificial ankle joint comprising, in combination, 
 a foot member,    a shin member,    an ankle joint for connecting said foot member to said shin member,    a motor for applying torque to said ankle joint to rotate said foot member with respect to said shin member,    one or more passive elastic members connected between said shin member and said foot member for storing energy when said foot member rotates about said ankle joint toward said shin member and for releasing energy to apply additional torque to rotate said foot member away from said shin member, and    one or more controllable variable damping elements for dissipating mechanical energy to arrest the relative motion of said foot and shin members at controllable times.    
     
     
         2 . An artificial ankle comprising, in combination, 
 a foot member,    a shin member,    an ankle joint for connecting said foot member for rotation with respect to said shin member,    a motor for applying torque to said ankle joint to rotate said foot member with respect to said shin member,    a controllable variable damping element for dissipating mechanical energy to arrest the relative motion of said foot member with respect to said shin member at controllable times, and    an elastic member operatively connected in series with said motor between said shin member and said foot member to store energy when the relative motion of said foot member and said shin member is being arrested by said controllable variable damping element and to thereafter apply an additional torque to said ankle joint when the relative motion of said foot member with respect to said shin member is no longer arrested by said controllable variable damping element.    
     
     
         3 . An artificial ankle comprising, in combination, 
 a foot member,    a shin member,    an ankle joint for connecting said foot member for rotation with respect to said shin member,    a motor connected for applying torque to said ankle joint to rotate said foot member with respect to said shin member at controllable times and to absorb energy from the rotation of said foot member with respect to said shin member at other times,    an elastic member operatively connected in series with said motor between said shin member and said foot member to store energy when said foot member is moved toward said shin member and to release energy and apply an additional torque to said ankle joint to aid said motor when said foot member moves away from said shin member, and    a controllable variable damping element for arresting the motion of said motor to control the amount of energy absorbed by said motor when said foot member is moved toward said shin member.    
     
     
         4 . An artificial ankle comprising, in combination, 
 a foot member,    a shin member,    an ankle joint for connecting said foot member for rotation with respect to said shin member,    a gearbox,    a motor connected for applying torque to said ankle joint through said gearbox to rotate said foot member with respect to said shin member,    a first controllable variable damping element for arresting the motion of said motor at controllable times, and    a second controllable variable damping element operatively connected between said motor and said gearbox for disconnecting said motor and said gearbox when the motion of said motor is arrested by said first controllable damping element so that the motion of said gearbox arrests the motion of said foot member with respect to said shin member.    
     
     
         5 . An artificial knee comprising, in combination, 
 a thigh member,    a shin member,    a knee joint for connecting said shin member for rotation with respect to said thigh member,    a motor connected for applying torque to said knee joint to rotate said shin member with respect to said thigh member at controllable times and to absorb energy from the rotation of said shin member with respect to said thigh member at other times,    one or more passive elastic members connected between said shin member and said thigh member for storing energy when said shin member rotates about said knee joint toward said thigh member and for releasing energy to apply additional torque to said knee joint to rotate said shin member away from said thigh member, and    a controllable variable damping elements for dissipating mechanical energy to arrest the relative motion of said thigh member and said shin member at controllable times.    
     
     
         6 . An artificial knee comprising, in combination, 
 a thigh member,    a shin member,    a knee joint for connecting said shin member for rotation with respect to said thigh member,    a motor connected for applying torque to said knee joint to rotate said shin member with respect to said thigh member at controllable times and to absorb energy from the rotation of said shin member with respect to said thigh member at other times,    an elastic member operatively connected in series with said motor between said shin member and said thigh member to store energy when said shin member is moved toward said thigh member and to release energy and apply an additional torque to said knee joint to aid said motor when said shin member moves away from said thigh member, and    a controllable variable damping element for arresting the motion of said motor to control the amount of energy absorbed by said motor when said foot member is moved toward said shin member.    
     
     
         7 . An artificial knee as set forth in  claim 6  further comprising a second elastic member operatively connected between said thigh member and said shin member in series with a second controllable variable damping element that supplies a high level of damping at controllable times to store energy in said second elastic member and a lower level of damping at other times to release the energy stored in said second elastic member.  
     
     
         8 . An artificial hip joint comprising, in combination, 
 a pelvis member,    a thigh member,    an hip joint for connecting said thigh member to said pelvis member,    a motor connected for applying torque to said hip joint to rotate said thigh member with respect to said pelvis member,    an elastic member operatively connected in series with a controllable variable damping element between said pelvis member and said thigh member, said controllable variable damping member providing a high level of damping at controllable times to store energy in said elastic member and a lower level of damping at other times to release the energy stored in said second elastic member.    
     
     
         9 . An artificial hip comprising, in combination, 
 a pelvis member,    a thigh member,    a hip joint for connecting said thigh member for rotation with respect to said pelvis member,    a motor connected for applying torque to said joint to rotate said thigh member with respect to said pelvis member,    a controllable variable damping element for dissipating mechanical energy to arrest the relative motion of said thigh member with respect to said pelvis member at controllable times, and    an elastic member operatively connected in series with said motor between said pelvis member and said thigh member to store energy from said motor when the relative motion of said thigh member and said pelvis member is being arrested by said controllable variable damping element and to thereafter apply an additional torque to said joint member when the relative motion of said thigh member with respect to said pelvis member is no longer arrested by said controllable variable damping element.    
     
     
         10 . An artificial hip comprising, in combination, 
 a pelvis member,    a thigh member,    a hip joint for connecting said thigh member for rotation with respect to said pelvis member,    a motor connected for applying torque to said hip joint to rotate said thigh member with respect to said pelvis member at controllable times and to absorb energy from the rotation of said thigh member with respect to said pelvis member at other times,    an elastic member operatively connected in series with said motor between said pelvis member and said thigh member to store energy when said thigh member is rotated upwardly member and to release energy and apply a torque to aid said motor when said thigh member rotates downwardly, and    a controllable variable damping element for arresting the motion of said motor to control the amount of energy absorbed by said motor when said foot member is moved toward said shin member.    
     
     
         11 . An artificial limb comprising, in combination, 
 first, second and third elongated skeletal members,    a first joint for connecting said first member for rotation with respect to said second member,    a second joint for connecting said second member for rotation with respect to said third member,    a motor connected between said first and third member for applying a force to rotate said first member with respect to said second member about said first joint and to rotate said second member with respect to said third member about said second joint,    one or more passive elastic members connected between said first and third members for storing energy when said first and third members move toward one another and for releasing energy when said members move away from one another, and    one or more controllable variable damping elements for dissipating mechanical energy to arrest the motion of said motor or the relative motion of said first and third members at controllable times.    
     
     
         12 . An artificial joint comprising, in combination, 
 first and second members connected at one or more joints for movement relative to one another,    a motor connected to said first and second members for applyin a force to move said first and second members with respect to one another,    one or more passive elastic members connected between said first and second members for storing energy when said first and second members move toward one another and for releasing energy when said members move away from one another, and    one or more controllable variable damping elements for dissipating mechanical energy to arrest the relative motion of said first and second members rotate at controllable times.    
     
     
         13 . An artificial joint as set forth in  claim 12  wherein said motor is connected in series with a first one of said one or more elastic members between said first and second members to store energy from said motor in said first one of said elastic members when the motion of said first and second members is being arrested by a first one of said one or more controllable damping elements.  
     
     
         14 . An artificial joint as set forth in  claim 13  wherein one of said one or more controllable variable damping elements is operatively connected in parallel with said motor to arrest the motion of said motor to store energy in said first one of said elastic members and to thereafter permit the motion of said motor to release the energy stored in said first one of said elastic members.  
     
     
         15 . An artificial joint as set forth in  claim 13  wherein at least a given one of said one or more elastic members is operatively connected in series with a given one of said one one or more controllable damping members and wherein said given one of said controllable damping members exhibits a higher damping level to cause energy to be stored in said given one of said one or more elastic members and exhibits a lower damping level to cause energy to be released from said given one of said one or more elastic members.  
     
     
         16 . An artificial joint as set forth in  claim 13  further including a gearbox connected to said motor to apply said force from said motor to move said first and second members relative to one another, a second controllable variable damping element for arresting the motion of said motor at controllable times, and a third controllable variable damping element operatively connected between said motor and said gearbox for disconnecting said motor and said gearbox when the motion of said motor is arrested by said second controllable damping element so that the motion of said gearbox arrests the motion of said first member with respect to said second member.  
     
     
         17 . An artificial joint as set forth in  claim 12  wherein at least a given one of said one or more elastic members is operatively connected in series with a given one of said one one or more controllable damping members and wherein said given one of said controllable damping members exhibits a higher damping level to cause energy to be stored in said given one of said one or more elastic members and exhibits a lower damping level to cause energy to be released from said given one of said one or more elastic members.  
     
     
         18 . An artificial joint as set forth in  claim 17  wherein a second one of said one or more controllable variable damping elements is operatively connected to arrest the motion of said motor.  
     
     
         19 . An artificial joint as set forth in  claim 12  wherein a second one of said controllable variable damping elements arrests the motion of said motor to control the amount of energy absorbed by said motor when said first member is moved toward said second member.  
     
     
         20 . An artificial joint as set forth in  claim 19  wherein at least a given one of said one or more elastic members is operatively connected in series with a given one of said one one or more controllable damping members and wherein said given one of said controllable damping members exhibits a higher damping level to cause energy to be stored in said given one of said one or more elastic members and exhibits a lower damping level to cause energy to be released from said given one of said one or more elastic members.  
     
     
         21 . An artificial joint as set forth in  claim 12  further including a gearbox connected to said motor to apply said force from said motor to move said first and second members relative to one another, a second controllable variable damping element for arresting the motion of said motor at controllable times, and a third controllable variable damping element operatively connected between said motor and said gearbox for disconnecting said motor and said gearbox when the motion of said motor is arrested by said second controllable damping element so that the motion of said gearbox arrests the motion of said first member with respect to said second member.