Separated Electric Motor Assisted Propulsion for Human-Powered Watercraft

Abstract

A propulsion system for hybrid electric watercraft for personal enjoyment that incorporates human power with electric motor assistance, energy storage and optional solar power to achieve increased watercraft speeds and/or reduced pedaling effort. Control electronics enable operator-adjustable electric motor assistance to the propulsion, thereby providing flexible pedal cadences and efforts and enjoyment for a wide variety of operators. An optional photovoltaic solar panel augments the power generation to extend travel time with motor assistance, and recharges the energy storage system. This invention enables a pleasure watercraft that is simultaneously lightweight, low cost, low maintenance, environmentally friendly with zero pollution, ultra-low noise, and thrilling to operate, while simultaneously providing a means of enjoyable exercise for operators of nearly all abilities.

1 . A propulsion system for watercraft comprising:
 a.) at least one human-powered propulsion means,   b.) at least one electric motor-powered propulsion means,   c.) the electric motor-powered propulsion means configured to provide propulsion as a function of the state of the human-powered propulsion means, whereby the electric motor-powered propulsion assists the human-powered propulsion means.   
   
   
       2 . The propulsion system of  claim 1 , further comprising a sensing means configured to provide a signal indicative of the state of the human-powered propulsion means, and a control means configured to receive said signal and to control the state of the electric motor-powered propulsion means according to said signal. 
   
   
       3 . The propulsion system of  claim 2 , wherein the state of the electric motor-powered propulsion means is further configured to be a function of said signal and a motor assistance factor. 
   
   
       4 . The propulsion system of  claim 3 , further comprising an operator interface means configured to enable the watercraft operator to adjust said motor assistance factor, whereby the amount of propulsion assistance from the electric-motor powered propulsion means is adjusted. 
   
   
       5 . The propulsion system of  claim 1 , further comprising an energy storage means configured to supply electrical power to the electric motor-powered propulsion means. 
   
   
       6 . The propulsion system of  claim 1 , further comprising a photovoltaic system means to provide power to the electric motor-powered propulsion means. 
   
   
       7 . The propulsion system of  claim 5 , further comprising a photovoltaic system means to provide power to said energy storage means. 
   
   
       8 . The propulsion system of  claim 2  wherein said control means comprises an electronics unit mounted within the housing of the electric motor-powered propulsion means. 
   
   
       9 . The propulsion system of  claim 3  wherein said motor assistance factor is modulated to simulate the travel through hills and valleys. 
   
   
       10 . The propulsion system of  claim 2 , wherein said signal is indicative of a rotational speed of the human-powered propulsion means. 
   
   
       11 . The propulsion system of  claim 2 , wherein said signal is indicative of a torque of the human-powered propulsion means. 
   
   
       12 . The propulsion system of  claim 1  further comprising an operator interface means configured to enable the operator to see performance parameters and/or operating information. 
   
   
       13 . The propulsion system of  claim 1  wherein the electric-motor powered propulsion means is further configured to optionally provide propulsion independent of the human-powered propulsion means. 
   
   
       14 . A method of propelling watercraft comprising:
 a.) exerting human effort to provide a first propelling force,   b.) providing a second propelling force via at least one electric motor-powered propulsion means,   c.) sensing of said human effort, and   d.) controlling said second propelling force based upon the sensed human effort, whereby said second propelling force assists said first propelling force to increase the speed of a watercraft.   
   
   
       15 . The method of  claim 14  further comprising providing a stored energy means to be used by the electric motor-powered propulsion means to provide said second propelling force. 
   
   
       16 . The method of  claim 14  further comprising providing a solar power means to be used by the electric motor-powered propulsion means to provide said second propelling force. 
   
   
       17 . The method of  claim 14  wherein said exerting of human effort comprises pedaling a human-powered propulsion means. 
   
   
       18 . The method of  claim 17  wherein said sensing of said human effort comprises sensing of the rotational speed of said human-powered propulsion means. 
   
   
       19 . The method of  claim 14  further comprising controlling the second propelling force by an operator adjustable assistance factor. 
   
   
       20 . A propulsion system for watercraft comprising:
 a.) a human-powered propulsion means,   b.) an electric motor-powered propulsion means,   c.) the electric motor-powered propulsion means configured to provide propulsion as a function of the rotational speed or torque of the human-powered propulsion means and of an assistance factor; wherein the assistance factor is adjustable by the operator, whereby the electric motor-powered propulsion means assists the human-powered propulsion means.