Submarine Cable Control by Use of Variable Specific Gravity and Diameter Cables and/or External Forces for Cables Used with Cable-Propelled Marine Vessels

Abstract

Cables for propulsion and/or guidance of cable ferries are disclosed which permit their use on longer ferry routes. One embodiment provides the use of cables for propulsion and/or guidance of cable ferries where the unit weight, density, specific gravity and/or diameter of the cable is variable over the length of the cable. According to one embodiment, heavier or denser cable is used adjacent to the terminals, while lighter or less dense cable is used for a middle section. Where sections have positive buoyancy, the cable may be tethered to one or more anchors. Where sections have negative buoyancy, the cable may be tethered to one or more floats.

1 . A cable wherein the unit weight, specific gravity, density or diameter of said cable is variable over the length of the cable, wherein said cable is used for propulsion and/or guidance of a cable-propelled marine vessel across a body of water between first and second terminal locations on opposing shores of said body of water, wherein said cable is configured to be fixed at either end thereof adjacent said first and second terminal locations and to pass through one or more pulleys, guides or drive wheels on said marine vessel, whereby when so configured the unit weight, specific gravity, density or diameter of said cable is selected at a location along the length of the cable between said first and second terminal locations according to the desired buoyancy of said cable at said location. 
     
     
         2 . The cable of  claim 1  wherein the unit weight, specific gravity, density or diameter of said cable is greater in sections of said cable closer to each said terminal location than in portions of said cable further from each said terminal location. 
     
     
         3 . The cable of  claim 1  wherein a combination of any one or more of the unit weight, specific gravity, density or diameter of said cable varies over the length of said cable. 
     
     
         4 . The cable of  claim 1  wherein the unit weight of said cable varies over the length of said cable. 
     
     
         5 . The cable of  claim 1  wherein the specific gravity of said cable varies over the length of said cable. 
     
     
         6 . The cable of  claim 1  wherein the density of said cable varies over the length of said cable. 
     
     
         7 . The cable of  claim 1  wherein the diameter of said cable varies over the length of said cable. 
     
     
         8 . The cable of  claim 1  wherein said cable comprises sections of wire rope cable at either end and a central section of synthetic rope. 
     
     
         9 . The cable of  claim 1  wherein said cable comprises a section of cable having negative buoyancy and a section of cable having positive buoyancy. 
     
     
         10 . The cable of  claim 1  wherein sections of said cable having positive buoyancy are tethered to one or more anchors by flexible connectors. 
     
     
         11 . The cable of  claim 1  wherein sections of said cable having negative buoyancy are tethered to one or more floats. 
     
     
         12 . The cable of  claim 10  wherein said flexible connectors are elastic. 
     
     
         13 . A cable system for propulsion and/or guidance of a cable-propelled marine vessel between terminals, comprising:
 i) a cable according to  claim 1  which comprises a cable section with positive buoyancy; and   ii) one or more anchors connected to said cable at spaced locations by flexible connectors.   
     
     
         14 . The cable system of  claim 13  wherein said flexible connectors are elastic. 
     
     
         15 . A cable system for propulsion and/or guidance of a cable-propelled marine vessel between terminals, comprising:
 i) a cable according to  claim 1  which comprises a cable section with negative buoyancy; and   ii) one or more flotation devices connected to said cable at spaced locations by flexible connectors.   
     
     
         16 . The cable system of  claim 15  wherein said flexible connectors are elastic. 
     
     
         17 . A cable system for propulsion and/or guidance of a cable-propelled marine vessel between terminals, comprising:
 i) a cable according to  claim 1  which comprises a section having positive buoyancy and a section having negative buoyancy; and   ii) one or more anchors or flotation devices connected to said cable at spaced locations by flexible connectors.   
     
     
         18 . The cable system of  claim 17  wherein said flexible connectors are elastic. 
     
     
         19 . A method of controlling the position or dynamics of a cable used for propelling or guiding a cable propelled or guided marine vessel over the path of said vessel on a maritime crossing of a body of water between two points on said path comprising the steps of:
 i) determining a selected path over said maritime crossing between said two points;   ii) selecting a cable according to  claim 1  for said propulsion and/or guidance to meet the characteristics of said crossing.   
     
     
         20 . A method of controlling the position or dynamics of a cable used for propelling or guiding a cable propelled or guided marine vessel over the path of said vessel on a maritime crossing of a body of water between two points on said path comprising the steps of:
 i) determining a selected path over said maritime crossing between said two points;   ii) selecting a cable according to  claim 1  for said propulsion and/or guidance to meet the characteristics of said crossing;   iii) selecting a combination and location of force-imposing elements for connection to said cable at spaced locations along the length of said cable to meet the desired characteristics of said crossing.   
     
     
         21 . The method of  claim 20  wherein said force-imposing elements are selected from the group consisting of:
 i) flotation devices connected to said cable at spaced locations by elastic connecting elements; 
 ii) anchoring devices connected to said cable at spaced locations by elastic connecting elements; 
 iii) elastic connecting devices connecting said cable to the bottom of said body of water; and 
 iv) a combination of the foregoing elements.