Variable Compliance Wheel

Abstract

A system for adjusting the compliance of a wheel is provided. In one embodiment, wheel segments are adjusted, causing the stiffness of the wheel to change. Such adjustments can be made while the wheel is rotating, allowing the wheel compliance to be changed while a vehicle is in motion.

What is claimed is: 
     
         1 . A system for modifying the stiffness of a rotating element comprising:
 an inner radial member;   a collar member disposed to slide on said inner radial member;   an outer radial member;   a plurality of spoke members, each of which having a first end fixed to said collar member and a second end fixed to said outer radial member;   an actuator coupled to said collar member;   said actuator axially moving said collar member to change a position of said plurality of spokes and thereby adjust a firmness of at least part of said rotating element.   
     
     
         2 . The system of  claim 1 , wherein said rotating element is a roller. 
     
     
         3 . The system of  claim 1 , wherein said actuator is a motor. 
     
     
         4 . The system of  claim 1 , wherein said actuator is an air spring. 
     
     
         5 . The system of  claim 1 , wherein said actuator is a hand-actuated cable spool. 
     
     
         6 . The system of  claim 1 , further comprising a control system coupled to said actuator for selectively moving said collar. 
     
     
         7 . The system of  claim 1 , further comprising:
 a control system;   said control system coupled to said actuator for independently moving said collar and said control system coupled to said second actuator for independently moving said second collar.   
     
     
         8 . A method of modifying the stiffness of a circular element during rotation comprising:
 providing a circular element coupled to an axle;   rotating said circular element with said axle; and   modifying a firmness of said circular element by directing an actuator to change a tension of a plurality of spokes disposed on said rotating element.   
     
     
         9 . The method of  claim 8 , wherein said modifying a firmness of said circular element by directing an actuator to change a tension of a plurality of spokes disposed on said rotating element includes adjusting a pressure of media within each of said plurality of spokes. 
     
     
         10 . The method of  claim 8 , wherein said modifying a firmness of said circular element by directing an actuator to change a tension of a plurality of spokes disposed on said rotating element includes applying power to said plurality of spokes so as to change a configuration of said plurality of spokes. 
     
     
         11 . The method of  claim 8 , wherein said modifying a firmness of said circular element by directing an actuator to change a tension of a plurality of spokes disposed on said rotating element includes independently changing a tension of a first plurality of spokes and a second plurality of spokes. 
     
     
         12 . The method of  claim 11 , wherein independently changing a tension of a first plurality of spokes and a second plurality of spokes further comprises changing a firmness of a portion of said circular element so as to modify a heading of a vehicle. 
     
     
         13 . The method of  claim 11 , wherein independently changing a tension of a first plurality of spokes and a second plurality of spokes further comprises:
 supporting a weight of an item on said circular element; and   changing a firmness of a portion of said circular element so as to change a direction of said item.   
     
     
         14 . A system for modifying the stiffness of a rotating element comprising:
 an inner radial member;   a first ring member disposed to slide on said inner radial member;   a second ring member disposed to slide on said inner radial member;   an outer radial member positioned substantially around said inner radial member;   a first plurality of elongated elements, each of which having a first end fixed to said first ring member and a second end fixed to said outer radial member;   a second plurality of elongated elements, each of which having a first end fixed to said second ring member and a second end fixed to said outer radial member;   a first actuator coupled to said first ring member for varying a stiffness of said first plurality of elongated elements;   a second actuator coupled to said second ring member for varying a stiffness of said first plurality of elongated elements;   a controller connected to said first actuator and said second actuator for independently controlling said first actuator and said second actuator.   
     
     
         15 . The system of  claim 14 , wherein said controller comprises a hand-actuated knob coupled to a cable spool. 
     
     
         16 . The system of  claim 14 , further comprising a tread band disposed around an outer circumference of said outer radial member for providing traction for a vehicle. 
     
     
         17 . The system of  claim 14 , further comprising a traction element disposed around said outer radial member for supporting and moving baggage. 
     
     
         19 . The system of  claim 14 , further comprising a traction element disposed around said outer radial member for moving paper. 
     
     
         20 . The system of  claim 14 , wherein said first and second actuators comprise a pneumatic motor. 
     
     
         21 . The system of  claim 14 , wherein said first and second actuators comprise a hydraulic motor. 
     
     
         22 . The system of  claim 14 , wherein said first and second actuators comprise an electric motor.