Systems and Methods for Gravitational Load Support

Abstract

A load support device includes a first link coupled to a load. A second link is configured to couple to footwear. The second link is pivotally coupled to the first link. The first and second link comprise a link assembly. A first compliant member is disposed between the load and the second link. The first compliant member includes a tension spring or a compression spring. The link assembly further includes a tension cable coupled to the first compliant member. A first actuator is coupled to the first compliant member to control a stiffness of the first compliant member. A sensor is configured to couple to a user to measure a physical state of the user. A control system controls the first actuator based on a gait activity. The first actuator is actuated based on the physical state of the user. The load support device is tuned based on the load.

What is claimed: 
     
         1 . A method of making a load support device, comprising:
 providing a first link coupled to a load;   providing a second link configured to couple to a footwear, the second link pivotally coupled to the first link;   disposing a first compliant member between the load and the second link;   coupling a first actuator to the first compliant member to control a stiffness of the first compliant member; and   providing a control system to control the first actuator based on a gait activity.   
     
     
         2 . The method of  claim 1 , further including coupling a second compliant element to the footwear. 
     
     
         3 . The method of  claim 1 , further including coupling a second actuator to the footwear. 
     
     
         4 . The method of  claim 1 , further including tuning the load support device based on the load. 
     
     
         5 . The method of  claim 1 , further including providing a sensor configured to couple to a user to measure a physical state of the user. 
     
     
         6 . The method of  claim 5 , further including actuating the first actuator based on the physical state of the user. 
     
     
         7 . A method of making a load support device, comprising:
 providing a first link coupled to a load;   providing a second link configured to couple to a footwear, the second link pivotally coupled to the first link;   disposing a first compliant member between the load and the second link; and   coupling a first actuator to the first compliant member to control a stiffness of the first compliant member.   
     
     
         8 . The method of  claim 7 , wherein the first compliant member includes a tension spring or a compression spring. 
     
     
         9 . The method of  claim 7 , further including coupling a second compliant member to the footwear. 
     
     
         10 . The method of  claim 7 , further including coupling a second actuator to the footwear. 
     
     
         11 . The method of  claim 7 , wherein the first compliant member and first actuator are configured to provide uni-directional support for gait. 
     
     
         12 . The method of  claim 7 , further including:
 providing a sensor configured to couple to a user to measure a physical state of the user; and   actuating the first actuator based on the physical state of the user.   
     
     
         13 . The method of  claim 7 , further including tuning the load support device based on the load. 
     
     
         14 . A load support device, comprising:
 a first link configured to couple to a load;   a second link configured to couple to a footwear and the first link;   a first compliant member disposed between the load and the second link; and   a first actuator coupled to the first compliant member to control a stiffness of the first compliant member.   
     
     
         15 . The load support device of  claim 14 , wherein the first compliant member further includes a helical spring. 
     
     
         16 . The load support device of  claim 14 , wherein the first link includes a tension cable coupled to the first compliant member. 
     
     
         17 . The load support device of  claim 14 , wherein the first compliant member includes a tension spring or a compression spring. 
     
     
         18 . The load support device of  claim 14 , further including a second compliant member coupled to the footwear. 
     
     
         19 . The load support device of  claim 18 , further including:
 a sensor configured to obtain a physical state measurement; and   a control system coupled to the sensor and first actuator, wherein the control system is configured to produce a command to control the first actuator based on the physical state measurement.   
     
     
         20 . A load support device, comprising:
 a link assembly configured to couple to a load and to a footwear;   a first compliant member coupled to the link assembly between the load and the footwear; and   an actuator coupled between the load and the footwear, the first compliant member and actuator configured to dissipate the load during gait.   
     
     
         21 . The load support device of  claim 20 , wherein the first compliant member further includes a helical spring. 
     
     
         22 . The load support device of  claim 20 , wherein the link assembly further includes a tension cable coupled to the first compliant member. 
     
     
         23 . The load support device of  claim 20 , wherein the first compliant member includes a tension spring or a compression spring. 
     
     
         24 . The load support device of  claim 20 , wherein the actuator is configured to control a stiffness of the first compliant member. 
     
     
         25 . The load support device of  claim 20 , further including a second compliant member coupled to the footwear.