Method and apparatus for automated control of marine vessel

Abstract

An improved autopilot system securely attached to a steering helm unit and mounted within the dashboard or pedestal of a marine vessel for automatic control over a vessel's direction of movement. One embodiment of an improved actuator utilizes endless belt members 212 , a driven pulley 210 attached to a steering shaft extension 208 passing through an axial bore in a back wall of a steering helm unit 52 , a drive pulley 206 to impart mechanical power to endless belt members 212 , and a tensioning pulley 306 connected to a clutch unit for controlling belt tension. A control box 58 provides electrical control over drive pulley 206 and clutch unit using motors. A time varying rotational position of driven pulley 210 is measured, from which a vessel's attempted steering direction can be deduced. The measurement of electrical current during clutch unit engagement and disengagement, can be used to gauge and control belt tension. A manual emergency override complements failsafe nature of clutch unit.

I claim: 
     
         1 . An autopilot actuator for use in a marine vessel comprising:
 a frame securely mounted to a steering helm unit housing under a dashboard panel of a marine vessel;   a driven pulley mounted to the rotating steering shaft of said steering helm unit,   a drive pulley mounted to a rotating drive shaft;   a single drive belt;   a mechanical clutch unit mounted to said frame;   wherein said mechanical clutch unit having a tensioner arm engaging said single drive belt to the said drive pulley and said driven pulley such that actuation of said mechanical clutch unit rotates said steering shaft of said steering helm unit to input a mechanical force from said rotating drive shaft for steering purposes;
 a de-tensioning pin mounted to said frame; and 
   wherein mount point of said mechanical clutch unit tensioner arm coupled with the mount point of said de-tensioning pin deforms the said drive belt into a shape that minimizes friction between said drive belt and said drive pulley when said clutch is de-actuated.   
     
     
         2 . The autopilot actuator according to  claim 1 , wherein said mechanical clutch unit further comprises:
 a clutch swing plate being pivotably connected to said frame;   said tensioner arm comprising a proximal end, a distal end, and a midsection;   a linkage comprising a proximal end and a distal end;   a de-tensioner arm comprising a proximal end, a distal end, and a midsection;   midsection of said tensioner arm being pivotably connected to said clutch swing plate;   a tensioner pulley rotatably attached to distal end of said tensioner arm;   distal end of said linkage being pivotably connected to said clutch swing plate;   proximal end of said linkage being pivotably connected to distal end of said de-tensioner arm;   midsection of said de-tensioner arm being pivotably connected to said actuator frame;   a pivot arm comprising a proximal end and a distal end;   a servo motor mounted to said actuator frame;   a servo arm comprising a proximal end and a distal end; promixal end of said servo arm rigidly attached to the rotating drive shaft of said servo motor;   distal end of said servo arm pivotably connected to proximal end of said pivot arm;   proximal end of said pivot arm pivotably connected to proximal end of said tensioner arm;   said servo motor electrically connected to said control box, such that the said mechanical clutch unit can be electrically controlled and electrically powered by said control box;   such that tension of said drive belt or tension of said plurality of drive belts can be deduced by monitoring electrical current used during said servo motor actuation;   such that actuation of said de-tensioner arm forces the clutch into an inoperative condition regardless of said tensioner arm state.   
     
     
         3 . The autopilot actuator according to  claim 2 , further comprising:
 a cable pivot arm comprising a proximal end and a distal end;   a cable comprising a proximal end and a distal end;   a cable housing comprising a proximal end, a distal end, and being axially hollow with an internal diameter larger than said cable;   a cable housing clamp mounted to said actuator frame;   distal end of said cable guide mounted to said cable housing clamp;   a cable routed through hollow interior of said cable housing such that both proximal and distal ends of said cable are accessible;   distal end of said cable rigidly attached to proximal end of cable pivot arm;   distal end of said cable pivot arm pivotably connected to proximal end of said secondary release arm.   a pull-release housing containing an axial bore perpendicular to and breaching both opposing faces of said pull-release housing;   a rod with a diameter smaller than said pull-release housing bore diameter;   a drive end of said cable guide mounted to said pull-release housing;   a drive end of said cable attached to distal end of said rod;   a handle directly attached to proximal end of said rod such that input linear mechanical force on said handle transmits the said input linear mechanical force to the said secondary release arm of said mechanical clutch.   
     
     
         4 . The autopilot actuator according to  claim 1 , further comprising:
 said driven pulley has a plurality of embedded magnets equally spaced along a circular path perpendicular to the said steering shaft;   
     
     
         5 . An autopilot system comprising:
 a frame securely mounted to a steering helm unit housing under a dashboard panel of a marine vessel;   a driven pulley mounted to the rotating steering shaft of said steering helm unit, a drive pulley mounted to a rotating drive shaft;   an autopilot actuator having Hall Effect sensors electrically connected to an control box;   a control box that can deduce both rotation angle and rotation direction of said driven pulley using Hall Effect sensor information;   such that said control box can detect spurious rotation in said steering helm which corresponds to said drive belt slipping between the driven pulley and drive pulley;   such that said spurious rotation can generate an alarm signal or some other corrective system action such as de-actuating the said clutch.