Artificial gill

Abstract

An artificial gill for enabling a user to breathe when in an underwater environment is provided. The artificial gill comprises a membrane configured to allow permeation of gas through the membrane and prevent permeation of water through the membrane. The membrane is made from or comprises polymethyl pentene, PMP. The artificial gill comprises a gas reservoir at least partially enclosed by a first surface of the membrane for providing gas for a user to breathe. The artificial gill also comprises a water flow device configured to direct a flow of water over a second, opposite surface of the membrane.

1 . An artificial gill for enabling a user to breathe when in an underwater environment, the artificial gill comprising:
 a membrane configured to allow permeation of gas through the membrane and prevent permeation of water through the membrane, wherein the membrane is made from or comprises polymethyl pentene, PMP;   a gas reservoir at least partially enclosed by a first surface of the membrane for providing gas for a user to breathe; and   a water flow device configured to direct a flow of water over a second, opposite surface of the membrane.   
     
     
         2 . The artificial gill of  claim 1 , wherein the membrane is configured to enable gaseous exchange between the gas reservoir and water in contact with the second surface of the membrane. 
     
     
         3 . The artificial gill of  claim 1 , wherein the membrane is configured to enable gaseous exchange at a sufficient rate such that, in use, a concentration of CO 2  in the gas reservoir is substantially 0.05% or less by volume, and optionally such that, in use, a concentration of O 2  in the gas reservoir is substantially 17.75% or greater by volume. 
     
     
         4 . The artificial gill of  claim 1 , wherein at least the second surface of the membrane comprises a non-porous skin. 
     
     
         5 . The artificial gill of  claim 1 , wherein the membrane comprises a plurality of fibres. 
     
     
         6 . The artificial gill of  claim 5 , wherein the fibres are hollow fibres. 
     
     
         7 . The artificial gill of  claim 6 , wherein the first surface of the membrane comprises inner surfaces of the hollow fibres. 
     
     
         8 . The artificial gill of  claim 6 , wherein the second surface of the membrane comprises the outer surfaces of the hollow fibres, and the water flow device is configured to direct water over the outer surfaces of the hollow fibres. 
     
     
         9 . The artificial gill of  claim 5 , wherein the fibres are arranged into a bundle, and optionally wherein the fibres are twisted, coiled, folded or woven into a bundle. 
     
     
         10 . The artificial gill of  claim 5 , wherein the fibres are knitted or woven into a mat, and optionally wherein the fibres are cross knitted into a mat. 
     
     
         11 . The artificial gill of  claim 5 , wherein the fibres comprise a microstructured texture configured to increase surface area and/or increase turbulence in water passing over the second surface of the membrane. 
     
     
         12 . The artificial gill of  claim 1 , wherein the water flow device comprises a pump. 
     
     
         13 . The artificial gill of  claim 1 , wherein the water flow device comprises a diver propulsion vehicle (DPV). 
     
     
         14 . The artificial gill of  claim 1 , wherein, in use, the gas reservoir is in fluid communication with facial respiratory features of a user. 
     
     
         15 . The artificial gill of  claim 1 , wherein the membrane is configured to provide sufficient gaseous exchange to remove at least 320 cm 3  of CO 2  per minute from the gas reservoir and add at least 140 cm 3  of O 2  per minute to the gas reservoir.