Sensor mapping to a global coordinate system using a marker grid

A sensor mapping method, comprising:

• receiving a first (x,y) coordinate identifying a first x-value and a first y-value in a global plane where a first corner of a marker grid is located in a space, wherein:
• the global plane represents (x,y) coordinates for the at least a portion of the space;
• the marker grid comprises a first marker and a second marker;
• the first marker is a first object that identifies a first location on the marker grid;
• and
• the second marker is a second object that identifies a second location on the marker grid;
• determining a second (x,y) coordinate identifying a second x-value and a second y-value in the global plane where the first marker is located based on a first offset from the first (x,y) coordinate for the first corner of the marker grid;
• determining a third (x,y) coordinate identifying a third x-value and a third y-value in the global plane where the second marker is located based on a second offset from the first (x,y) coordinate for the first corner of the marker grid;
• receiving a first frame of the global plane for at least a portion of the marker grid in the space, wherein:
• the first frame comprises a plurality of pixels;
• and
• each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column;
• identifying a first pixel within the first frame corresponding with the first marker;
• identifying a second pixel within the first frame corresponding with the second marker;
• determining a first pixel location for the first pixel, wherein the first pixel location comprises a first pixel row and a first pixel column of the first frame;
• determining a second pixel location for the second pixel, wherein the second pixel location comprises a second pixel row and a second pixel column of the first frame;
• and
• generating a first homography based on the second (x,y) coordinate for the first marker, the third (x,y) coordinate for the second marker, the first pixel location, and the second pixel location, wherein the first homography comprises coefficients that translate between pixel locations in the first frame and (x,y) coordinates in the global plane.

A computer program comprising executable instructions stored in a non-transitory computer readable medium that when executed by a processor causes the processor to:

• receive a first (x,y) coordinate identifying a first x-value and a first y-value in a global plane where a first corner of a marker grid is located in a space, wherein:
• the global plane represents (x,y) coordinates for the at least a portion of the space;
• the marker grid comprises a first marker and a second marker;
• the first marker is a first object that identifies a first location on the marker grid;
• and
• the second marker is a second object that identifies a second location on the marker grid;
• determine a second (x,y) coordinate identifying a second x-value and a second y-value in the global plane where the first marker is located based on a first offset from the first (x,y) coordinate for the first corner of the marker grid;
• determine a third (x,y) coordinate identifying a third x-value and a third y-value in the global plane where the second marker is located based on a second offset from the first (x,y) coordinate for the first corner of the marker grid;
• receive a first frame of the global plane for at least a portion of the marker grid in the space, wherein:
• the first frame comprises a plurality of pixels;
• and
• each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column;
• identify a first pixel within the first frame corresponding with the first marker;
• identify a second pixel within the first frame corresponding with the second marker;
• determine a first pixel location for the first pixel, wherein the first pixel location comprises a first pixel row and a first pixel column of the first frame;
• determine a second pixel location for the second pixel, wherein the second pixel location comprises a second pixel row and a second pixel column of the first frame;
• and
• generate a first homography based on the second (x,y) coordinate for the first marker, the third (x,y) coordinate for the second marker, the first pixel location, and the second pixel location, wherein the first homography comprises coefficients that translate between pixel locations in the first frame and (x,y) coordinates in the global plane.