Method and apparatus for accurately positioning a tool on a mobile machine using on-board laser and positioning system

A method of positioning a tool on a mobile unit during operation of the mobile unit within a work area, the method comprising:

• storing on-board the mobile unit a terrain model of the work area, the terrain model including data on the locations of each of a plurality of selectable reference points;
• using a positioning system on-board the mobile unit to determine the location of the mobile unit;
• and
• using one of the plurality of selectable stationary reference points and the location of the mobile unit to determine a positional adjustment for the tool.

A method of accurately positioning a tool on a mobile unit, the method comprising:

• storing on-board the mobile unit a terrain model of an area including data indicating the locations of each of a plurality of fixed reference points;
• using an on-board positioning system to determine the location of the mobile unit;
• selecting one of the plurality of fixed reference points based on the terrain model and the location of the mobile unit;
• aiming a laser beam generated by an on-board laser at the selected reference point;
• computing a displacement based on a parameter associated with the laser beam and the selected reference point;
• and
• determining a positional adjustment for the tool based on the computed displacement.

A method of automatically positioning a tool on a mobile machine operating within an area, the method comprising:

• using an on-board satellite positioning system location device to determine a horizontal location of the machine;
• providing an on-board digital terrain model (DTM), the DTM indicating the locations of each of a plurality of stationary reflectors located about the area and design elevations for a plurality of locations within the area;
• selecting and determining the location of one of the plurality of stationary reflectors based on the horizontal location of the machine and the DTM, including determining an approximate elevation of the selected reflector;
• using an on-board total station to locate the selected reflector based on the determined location;
• using an on-board scanning laser to lock onto the selected reflector based on the approximate elevation;
• computing an angle between the laser and the selected reflector;
• computing an adjustment for the tool based on the angle and a design elevation from the DTM corresponding to the location of the machine;
• and
• adjusting the position of the tool based on the computed adjustment.

An on-board system for enabling positioning of an adjustable tool in a mobile unit, the on-board system comprising:

• storage means for storing data representing the locations of a plurality of stationary reference points;
• a positioning system to determine the location of the mobile unit;
• a laser unit to generate a laser beam;
• selection means for selecting a stationary reference point of the plurality of stationary reference points, based on said data and the location of the mobile unit;
• aiming means for aiming the laser beam at the selected stationary reference point;
• means for determining a parameter associated with the laser beam and the selected stationary reference point;
• and
• means for determining a displacement of the tool based on the parameter.

In a mobile unit having a tool, an on-board system for enabling accurate positioning of the tool, the on-board system comprising:

• a precise positioning system configured to determine the location of the mobile unit;
• a laser unit configured to generate a laser beam;
• storage means for storing a terrain model of an area including data indicating the locations of each of a plurality of fixed reference points;
• selection means for selecting one of the plurality of fixed reference points;
• aiming means for directing the laser beam to the selected reference point;
• means for computing a displacement based on a measured parameter associated with the laser beam and the selected reference point;
• and
• means for determining a positional adjustment for the tool based on the computed displacement.

An on-board system in a mobile unit having a tool, the system for enabling accurate positioning of the tool, the system comprising:

• a satellite positioning system unit configured to determine a horizontal location of the mobile unit;
• a survey measurement unit;
• a laser unit;
• a storage unit having stored therein a terrain model, including data indicating the locations of each of a plurality of reflectors positioned about an area;
• and
• a processor configured to select and determine the location of one of the plurality of reflectors based on the terrain model;
• wherein the survey measurement unit is configured to locate the selected reflector;
• and
• wherein the processor is further configured to:
• compute an angle between the selected reflector and a laser beam generated by the laser unit;
• compute a positional adjustment for the tool based on the computed angle;
• and
• output signals for enabling repositioning of the tool based on the computed adjustment.

An on-board system for automatically positioning a tool on a mobile machine operating within an area, the system comprising:

• positioning means for determining a precise horizontal location of the machine;
• storage means for storing an on-board digital terrain model (DTM), the DTM indicating the locations of each of a plurality of stationary reflectors located about the area and design elevations for a plurality of locations within the area;
• means for selecting one of the plurality of stationary reflectors based on the DTM;
• means for determining coordinates of the selected stationary reflector, including means for determining an approximate elevation of the selected reflector;
• locating means for locating the selected reflector based on the coordinates;
• light-emitting means for optically acquiring the selected reflector based on the approximate elevation based on a transmitted light beam;
• means for computing an adjustment for the tool based on an angle between the light beam and the selected reflector and a design elevation from the DTM corresponding to the location of the machine;
• and
• means for adjusting the position of the tool based on the computed adjustment.

An on-board system in a mobile machine having a tool, for enabling accurate positioning of the tool, the system comprising:

• a satellite positioning system receiver configured to determine a horizontal location of the machine;
• a robotic total station with an integrated a scanning laser;
• a storage device having stored therein a digital terrain model (DTM), including data indicating the locations of each of a plurality of stationary reflectors positioned at various locations about an area and design elevations for a plurality of locations within the area;
• a tool controller configured to control the position of the tool;
• and
• a processor configured to:
• select and determine the location of one of the plurality of stationary reflectors based on the horizontal location of the machine and the DTM, including determining an approximate elevation of the selected reflector;
• and
• generate a first control signal including an indication of the location and approximate elevation of the selected reflector;
• wherein the total station is configured to:
• locate the selected reflector in response to the first control signal;
• and
• acquire the selected reflector using the scanning laser;
• wherein the processor is further configured to:
• compute an angle between the laser and the selected reflector;
• compute an adjustment for the tool based on the angle and a design elevation from the DTM corresponding to the location of the machine;
• and
• provide the first control signals to the tool controller to cause the tool controller to alter the position of the tool based on the computed adjustment.