System and method for integrating automatic electrical steering with GNSS guidance

Abstract

A guidance and vehicle control system for automatically steering a vehicle, such as an agricultural vehicle or a tractor, through a field. The system includes a GNSS receiver and antenna for determining the vehicle's instantaneous position, a guidance CPU, and an automatic steering subsystem integrated with the vehicle's electrical power system. The automatic steering subsystem can be interfaced with the steering column of the vehicle, and mechanically activates the steering column, thereby steering the vehicle according to instructions received from the CPU based upon the vehicle's position and a predetermined path. An interrupt element, such as a wheel movement sensor or a slip gear, may be interfaced with the automatic steering subsystem to allow for manual steering override of the automatic steering control.

Having thus described the disclosed subject matter, what is claimed as new and desired to be secured by Letters Patent is: 
     
       1. A guidance system for a vehicle including steerable wheels and a steering mechanism connected to the steerable wheels, the steering mechanism including a steering column mounting a steering wheel, which guidance system includes:
 a GNSS-based guidance subsystem including a GNSS receiver, a guidance processor including a guidance CPU connected to the a GNSS-based guidance subsystem and a GNSS receiver thereof, an output from said guidance processor CPU for providing a steering signal output, a graphical user interface (GUI) connected to the guidance processor CPU, and a memory storage device connected to the processor guidance CPU; 
 an automatic steering subsystem including a drive connected to the steering mechanism and an encoder connected to the steering mechanism and the guidance processor CPU; 
 said drive including a motor connected to said an electrical subsystem; and 
 an electrical subsystem connected to said automatic steering subsystema slip gear mechanically interfaced with said steering mechanism adapted to disconnect said drive from said steering mechanism. 
 
     
     
       2. The system of  claim 1 , further comprising:
 the vehicle steering mechanism including a steering column mounting a steering wheel; and 
 a worm drive interfacing with said automatic steering subsystem and said steering column, wherein the slip gear is adapted to bypass said worm drive. 
 
     
     
       3. The system of  claim 2 , wherein said automatic steering subsystem is mounted in proximity to said steering column. 
     
     
       4. The system of  claim 2 , further comprising a mounting rod mounting said automatic steering subsystem to said steering column. 
     
     
       5. The system of  claim 2 , further comprising:
 a wheel movement detection switch integrated into said automatic steering system; and 
 said wheel movement detection switch adapted to interrupt said automatic steering subsystem when said steering wheel is manually turned. 
 
     
     
       6. The system of  claim 2 , further comprising:
 a slip gear adapted to bypass said worm drive, said slip gear mechanically interfaced with said steering column.   
     
     
       7. A system for controlling an agricultural vehicle including a steering column connected to steerable wheels and mounting a steering wheel, which guidance system includes:
 a GNSS guidance subsystem including an RF converter, a GNSS receiver, and a GNSS antenna; 
 an automatic steering subsystem including a worm drive having a worm gear, and an encoder; said automatic steering subsystem mechanically interfaced with said steering column via said worm drive and  
 an electrical subsystem adapted for powering a plurality of electrical components of the vehicle, said electrical subsystem interfaced with said automatic steering subsystem via a power cable; 
 said worm drive powered by a motor connected to said an electrical subsystem; 
 a guidance CPU electronically connected to said GNSS guidance subsystem, and said automatic steering subsystem, a graphical user interface (GUI), and a memory storage device; and  
 said automatic steering subsystem mechanically interfaced with said steering column via said worm drive; 
 a mounting rod mounting said automatic steering subsystem to said steering column; 
 a wheel movement detection switch integrated into said automatic steering system; and 
 said wheel movement detection switch adapted to interrupt said automatic steering subsystem when said steering wheel is manually turned a slip gear mechanically interfaced with said steering column and adapted to bypass said worm drive. 
 
     
     
       8. A method of controlling a vehicle having a steering column attached to a steering wheel, the method comprising the steps:
 providing a GNSS guidance subsystem including an RF converter, a GNSS receiver and a GNSS antenna; 
 providing an automatic steering subsystem including a worm drive having a worm gear, and an encoder; 
 connecting said GNSS guidance subsystem and said automatic steering subsystem to an electrical subsystem integrated into the vehicle, said electrical subsystem powering a plurality of electrical components connected to said vehicle; 
 interfacing said worm drive with the steering column of the vehicle; 
 providing a guidance CPU electronically connected to said GNSS guidance subsystem and said automatic steering subsystem; 
 locating said vehicle location with said GNSS guidance subsystem; 
 sending guidance instructions to said automatic steering subsystem with said guidance CPU; and 
 steering the vehicle along a predetermined path by mechanically operating said steering column with said automatic steering subsystem, thereby guiding the vehicle; 
 providing a slip gear interfaced with said steering column; 
 activating said slip gear, thereby deactivating said automatic steering subsystem; 
 deactivating said slip gear; and 
 reactivating said automatic steering subsystem. 
 
     
     
       9. The method according to  claim 8 , further comprising the steps:
 providing a slip gear interfaced with said steering column;   activating said slip gear, thereby deactivating said automatic steering subsystem;   deactivating said slip gear; and   reactivating said automatic steering subsystem.   
     
     
       10. The method according to  claim 8 , further comprising the steps:
 providing a wheel movement detection switch integrated into said automatic steering system; 
 detecting manual interference of said steering wheel with said wheel movement detection switch; and 
 activating said automatic steering subsystem. 
 
     
     
       11. A system for controlling a vehicle including a steering column mounting a steering wheel, comprising:
 a guidance central processing unit (CPU) to:   receive signals from a global navigation satellite system (GNSS);   identify a location of the vehicle based on the signals received from the GNSS;   send guidance instructions to an automatic steering subsystem to steer the vehicle along a predetermined path based on the identified location of the vehicle;   detect manual interference of the automatic steering of the vehicle by the automatic steering subsystem;   deactivate the automatic steering subsystem based on the detected manual interference; and   activate a slip gear interfaced with the steering column to deactivate the automatic steering subsystem.    
     
     
       12. The system of claim 11, further comprising the guidance CPU to cause the automatic steering subsystem to steer the vehicle by controlling movement of the steering column for the steering wheel.  
     
     
       13. The system of claim 11, further comprising the guidance CPU to:
 receive a signal from a steering wheel movement detection switch to detect the manual interference of the automatic steering of the vehicle; and   deactivate the automatic steering subsystem in response to the signal from the steering wheel movement detection switch.