Method and apparatus for excavating earth to a desired depth

A method of constructing an excavating system for use in excavating an opening having a below surface grade opening floor in the earth's surface of predetermined depth comprising:

• providing an excavation vehicle;
• providing an elevation measurement vehicle supported on independently driven traction members for maneuvering upon said floor and having a vertically telescopic measurement device movable between retracted and extended positions with a laser beam target at its upper end;
• providing a laser transit to be located adjacent said opening and having a laser beam transmitter thereon;
• and
• providing remote control communications between said excavation vehicle and said elevation measurement vehicle for remotely controlling maneuvering movement of said independently driven traction members and vertical movement of said measurement device between its retracted and extended positions from said excavation vehicle.

A method of constructing an excavating system for use in excavating an opening having a below surface grade opening floor in the earth's surface of predetermined depth comprising:

• providing an excavation vehicle;
• providing an elevation measurement vehicle supported on driven traction members for maneuvering upon said floor and having a vertically telescopic measurement device with a laser beam target at its upper end;
• providing a laser transit to be located adjacent said opening and having a laser beam transmitter thereon;
• providing remote control communications between said excavation vehicle and said elevation measurement vehicle for remotely controlling maneuvering movement of said elevation measurement vehicle and vertical movement of said measurement device from said excavation vehicle;
• and
• providing a debris member on said elevation measurement vehicle for movement between a lowered position for moving debris from said earth's surface to facilitate obtaining an accurate elevation measurement and a raised position.

An excavating system for excavating a below grade floor surface in the earth comprising in combination:

• an excavation vehicle;
• an elevation measurement vehicle supported on motor driven traction members for maneuvering movement to various locations on said floor surface;
• a vertically moveable motor driven vertical measurement device having a beam target on said elevation measurement vehicle;
• a beam emitter to be positioned above said floor for transmitting a beam to said beam target at a precise elevation;
• and
• remote control connections between said excavation vehicle and said traction members and said measurement device for remotely controlling their movement from said excavator vehicle.