Flexible actuator

Abstract

A flexible actuator is disclosed which comprises an expansion chamber defined by an inner wall of an expandable girdle, the expandable girdle being connected to at least two anchoring points. The expansion chamber has at least one fluid inlet to allow pressurized fluid into the chamber. The expansion chamber capable of acquiring a minimum volume and a maximum volume. The flexible actuator is adapted to transform a fluid pressure force against the inner wall of the expandable girdle into a traction force at the two anchoring points when the expansion chamber is inflated by the pressurized fluid entering through the fluid inlet.

The embodiments of the invention for which an exclusive privilege or property is claimed are defined as follows:  
     
         1 . A flexible actuator comprising: 
 an expansion chamber defined by an inner wall of an expandable girdle, said expandable girdle connected to at least two anchoring points;    said expansion chamber having at least one fluid inlet;    said expansion chamber capable of acquiring a minimum volume and a maximum volume;    said flexible actuator adapted to produce a traction force at said at least two anchoring points when said expansion chamber is inflated by pressurized fluid entering through said at least one fluid inlet.    
     
     
         2 . A flexible actuator as defined in  claim 1  wherein said flexible actuator generate work when said expansion chamber expands between said minimum dimension and said maximum dimension.  
     
     
         3 . A flexible actuator as defined in claims  1  or  2  wherein said flexible actuator acquires a relax state when said expansion chamber is at said minimum dimension, a fully contracted state when said expansion chamber is at said maximum dimension, and a partially contracted state when said expansion chamber is in between said minimum dimension and said maximum dimension.  
     
     
         4 . A flexible actuator as defined in  claims 1  to  3  wherein said expandable girdle comprises an elastomeric matrix reinforced with filaments.  
     
     
         5 . A flexible actuator as defined in  claim 4  wherein said fibers include a plurality of filaments oriented randomly.  
     
     
         6 . A flexible actuator as defined in  claim 4  wherein said fibers include a plurality of filaments braided in a crisscross pattern.  
     
     
         7 . A flexible actuator as defined in  claim 6  wherein said fibers include a plurality of filaments oriented along a longitudinal direction generally corresponding to an axis defined said at least two anchoring points.  
     
     
         8 . A flexible actuator as defined in  claim 7  wherein said filaments oriented along a longitudinal direction extend continuous along said expansion chamber.  
     
     
         9 . A flexible actuator as defined in  claim 8  comprising at least one layer of said filaments braided in a criss-cross pattern and at least one layer of said filaments oriented along a longitudinal direction.  
     
     
         10 . A flexible actuator as defined in  claim 9  comprising a plurality of layers of said filaments braided in a criss-cross pattern and a plurality of said filaments oriented along a longitudinal direction.  
     
     
         11 . A flexible actuator as defined in  claim 10  wherein said expansion chamber comprises a fluid outlet separate from said fluid inlet, said pressurized fluid entering through said fluid inlet and exiting through said fluid outlet.  
     
     
         12 . A flexible actuator as defined in  claim 1  wherein said at least two anchoring points comprise fastening means for connecting said flexible actuator to a structure.  
     
     
         13 . A flexible actuator as defined in  claim 12 , wherein said fluid inlet coincides with one of said fastening means.  
     
     
         14 . A flexible actuator as defined in  claim 13 , wherein said fluid outlet coincides with another of said fastening means.  
     
     
         15 . A flexible actuator as defined in  claim 14 , wherein said structure comprises a fluid conduit in fluid communication with said fluid inlet for supplying said expansion chamber with pressurized fluid.  
     
     
         16 . A flexible actuator as defined in  claim 1  wherein said expandable girdle is an elastomeric body; said inner wall of said expandable girdle having varying thickness distributed around said expansion chamber.  
     
     
         17 . A flexible actuator comprising: 
 an expansion chamber defined by an inner wall of an expandable girdle, said expandable girdle connected to at least two anchoring points;    said expansion chamber having at least one fluid inlet;    said expansion chamber capable of acquiring a minimum volume and a maximum volume;    said flexible actuator adapted to transform a fluid pressure force against said inner wall of said expandable girdle into a traction force at said at least two anchoring points when said expansion chamber is inflated by pressurized fluid entering through said at least one fluid inlet.