Patent ID: 7066276

Claim:
A method of excavating a below grade opening having a lower floor surface at a construction site, comprising the steps of: providing a laser transmitter for emitting a laser beam signal at a predetermined elevation; providing a first vehicle; providing a remotely controlled receiver for receiving the laser beam signal emitted from said laser transmitter; connecting said first vehicle for remote control operation; mounting said receiver to said first vehicle for vertical movement thereon to provide a depth of opening measurement; providing a second vehicle separate from said first vehicle and having an excavator for excavating said opening; maneuvering said second vehicle to at least partially excavate said opening; maneuvering said first vehicle by remote control within said opening being excavated to position the receiver for receipt of the laser beam signal being sent by the laser transmitter; remotely vertically moving said receiver and remotely obtaining an elevation measurement from the first vehicle for an area of the floor surface occupied by said first vehicle; maneuvering said first vehicle by remote control to a new location on said floor surface, and maneuvering said second vehicle to further excavate said area to obtain the desired depth over said floor surface.