The AccuGrade system provides flat, single, or dual-slope surfaces within 6 mm of grade.
The AccuGrade system provides flat, single, or dual-slope surfaces within 6 mm of grade.

A laser-based system from Caterpillar Inc., Peoria, Ill. (www.cat.com), helps operators of track-type tractors fine-grade fields more accurately and quickly. Called the AccuGrade Laser Grade Control System, it is designed for earthmoving applications requiring tight tolerances and high production. It is said to provide flat, single, or dual-slope surfaces within 6 mm (0.24 in.) of grade. Caterpillar says the system can minimize both the amount of material that must be moved and the distance it is moved.

The system features laser receivers mounted on the blade that automatically control the machine's hydraulic system. A ground-based laser transmitter sends precise elevation information. The receivers measure the deviation from finish grade and, in turn, automatically adjust the blade's lift and tilt as the machine moves. The transmitter emits a 360° beam, creating a grade reference over the entire work area for multiple machines.

An in-cab display has an LED grade indicator and a backlit graphical LCD numeric elevation display. It shows the blade position relative to grade and indicates cut or fill as the tractor moves over a work area. Based on that information, a dual hydraulic control valve automatically adjusts the machine's cutting edge height to maintain precise grade control.

Operators can select either automatic or manual operating modes. They typically use manual blade control for rough grading and switch to automatic mode for fine grading. The AccuGrade system is currently available on Caterpillar D3G, D4G, and D5G track-type tractors.