Sensor system and method for use with an automated guided vehicle (agv)

Abstract

A sensor system for use with an automated guided vehicle (AGV) includes a plurality of sensor units electronically coupled to a sensor control module via parallel communications. Each sensor unit may include a sensor array having a plurality of sensor elements, a conditioning circuit having one or more filter/amplifiers, and a conversion circuit. The sensor control module may be configured to communicate with other AGV components via serial communications. The sensor system is capable of obtaining and storing sensor readings with or without associated offset values and can use the sensor readings to determine the center of a magnetic field using methods that require relatively little processing power. A method of calibrating the sensor system may include determining and storing offset values for a plurality of sensor elements and may be performed with the sensor system installed or uninstalled to the AGV.

1 . A sensor system for use with an automated guided vehicle (AGV), comprising:
 a sensor housing being attached to the AGV; and   a sensor board being at least partially located within the sensor housing and including a plurality of sensor units electronically coupled to a sensor control module, wherein each of the sensor units interacts with an indicating system that follows a pre-determined path along the ground and each of the sensor units includes:
 a sensor array having a plurality of sensor elements, the sensor elements take sensor readings regarding the position of the AGV with respect to the indicating system; 
 a conditioning circuit being electronically coupled to the sensor array and having a plurality of filter/amplifiers, the filter/amplifiers process the sensor readings from the sensor array; and 
 a conversion circuit being electronically coupled to the conditioning circuit, the conversion circuit converts the sensor readings from the conditioning circuit for transmission to the sensor control module. 
   
     
     
         2 . The sensor system of  claim 1 , further comprising:
 one or more additional sensor board(s) having a plurality of sensor elements, each of the sensor boards is electronically coupled to the sensor control module and is distinguished from the other sensor boards through the use of dipswitches.   
     
     
         3 . The sensor system of  claim 2 , wherein the sensor boards include a snap-in connector located at one or more end(s) of the sensor board so that multiple sensor boards can be connected end-to-end. 
     
     
         4 . The sensor system of  claim 2 , wherein the sensor boards extend in a generally parallel orientation across at least a portion of the width of the AGV and the sensor boards help the AGV navigate in a forward direction along the predetermined path. 
     
     
         5 . The sensor system of  claim 2 , wherein one or more of the sensor boards extends across at least a portion of the width of the AGV and helps the AGV navigate in a forward direction along the pre-determined path, and one or more of the sensor boards extends along at least a portion of the length of the AGV and helps the AGV navigate in a sideways direction from the pre-determined path. 
     
     
         6 . The sensor system of  claim 1 , wherein the plurality of sensor elements include magnetic field sensing elements that are able to evaluate both the strength and the direction of a magnetic field produced by a magnetic indicating system located along the ground. 
     
     
         7 . The sensor system of  claim 1 , wherein the sensor control module is electronically coupled to the plurality of sensor units via a parallel communications and is electronically coupled with an AGV supervisory device via a serial communications. 
     
     
         8 . The sensor system of  claim 1 , wherein the sensor housing is pivotally attached to an underside of the AGV so that the sensor housing can pivot out of the way when the AGV encounters an obstacle in the pre-determined path. 
     
     
         9 . A sensor system for use with an automated guided vehicle (AGV), comprising:
 a sensor housing being attached to the AGV; and   a sensor board being at least partially located within the sensor housing and including a plurality of sensor units electronically coupled to a sensor control module, wherein each of the sensor units interacts with an indicating system that follows a pre-determined path along the ground and each of the sensor units includes:
 a sensor array having a plurality of sensor elements for receiving sensor readings associated with position of the AGV with respect to the indicating system; 
 a conditioning circuit being coupled to the sensor array for conditioning the sensor readings; and 
 a conversion circuit coupled to the conditioning circuit to prepare the conditioned sensor readings for transmission to the sensor control module. 
   
     
     
         10 . The sensor system of  claim 9 , further comprising:
 one or more additional sensor board(s) having a plurality of sensor elements, each of the sensor boards is electronically coupled to the sensor control module and is distinguished from the other sensor boards through the use of dipswitches.   
     
     
         11 . The sensor system of  claim 10 , wherein the sensor boards include a snap-in connector located at one or more end(s) of the sensor board so that multiple sensor boards can be connected end-to-end. 
     
     
         12 . The sensor system of  claim 10 , wherein the sensor boards extend in a generally parallel orientation across at least a portion of the width of the AGV and the sensor boards help the AGV navigate in a forward direction along the pre-determined path. 
     
     
         13 . The sensor system of  claim 10 , wherein one or more of the sensor boards extends across at least a portion of the width of the AGV and helps the AGV navigate in a forward direction along the pre-determined path, and one or more of the sensor boards extends along at least a portion of the length of the AGV and helps the AGV navigate in a sideways direction from the pre-determined path. 
     
     
         14 . The sensor system of  claim 9 , wherein the plurality of sensor elements include magnetic field sensing elements that are able to evaluate both the strength and the direction of a magnetic field produced by a magnetic indicating system located along the ground. 
     
     
         15 . The sensor system of  claim 9 , wherein the sensor control module is electronically coupled to the plurality of sensor units via a parallel communications and is electronically coupled with an AGV supervisory device via a serial communications. 
     
     
         16 . The sensor system of  claim 9 , wherein the sensor housing is pivotally attached to an underside of the AGV so that the sensor housing can pivot out of the way when the AGV encounters an obstacle in the pre-determined path. 
     
     
         17 . A sensor system for use with an automated guided vehicle (AGV), comprising:
 a pivotable sensor housing being pivotally coupled to the AGV; and   a sensor board being at least partially located within the sensor housing and including a plurality of detachably couplable sensor units electronically coupled to a sensor control module, wherein each of the sensor units interacts with an indicating system that follows a predetermined path along the ground and each of the sensor units includes:
 a sensor array having a plurality of sensor elements, the sensor elements take sensor readings regarding the position of the AGV with respect to the indicating system; 
 a conditioning circuit being electronically coupled to the sensor array and having a plurality of filter/amplifiers, the filter/amplifiers process the sensor readings from the sensor array; and 
 a conversion circuit being electronically coupled to the conditioning circuit, the conversion circuit converts the sensor readings from the conditioning circuit for transmission to the sensor control module. 
   
     
     
         18 . The sensor system of  claim 17 , further comprising:
 one or more additional sensor board(s) having a plurality of sensor elements, each of the sensor boards is electronically coupled to the sensor control module and is distinguished from the other sensor boards through the use of dipswitches, wherein the sensor boards include a snap-in connector located at one or more end(s) of the sensor board so that multiple sensor boards can be connected end-to-end.   
     
     
         19 . The sensor system of  claim 17 , further comprising one or more additional sensor board(s) having a plurality of sensor elements, each of the sensor boards is electronically coupled to the sensor control module, wherein one or more of the sensor boards extends across at least a portion of the width of the AGV and helps the AGV navigate in a forward direction along the pre-determined path, and one or more of the sensor boards extends along at least a portion of the length of the AGV and helps the AGV navigate in a sideways direction from the pre-determined path. 
     
     
         20 . The sensor system of  claim 17 , wherein the plurality of sensor elements include magnetic field sensing elements that are able to evaluate both the strength and the direction of a magnetic field produced by a magnetic indicating system located along the ground.