Caterpillar has announced a significant software update for its Cat® Grade with 3D system on the 140 and 150 series motor graders. While automated grade control is standard for rough grading, finish grading on uneven surfaces has remained a manual challenge. If the machine crests a hill or enters a depression, the fixed-angle blade can inadvertently dig into the soil, leaving a scar that requires rework. Caterpillar's new "Slope Assist" module uses the machine's existing IMU (Inertial Measurement Unit) to actively manage the blade pitch and height relative to the chassis angle.
The system works by monitoring the pitch and roll of the motor grader chassis 100 times per second. When the rear tandem axles drop into a dip, the system predicts that the mid-mounted blade will tilt forward. To compensate, the automation system automatically commands the lift cylinders to raise the blade tip by the precise distance required to maintain a flat cutting plane. Conversely, when the machine climbs a rise, the system tilts the blade forward to maintain the correct attack angle, preventing the heel of the moldboard from dragging and creating a "curled" windrow.
This active blade management eliminates the need for the operator to constantly "fight" the hydraulics when transitioning between cut and carry modes. In a recent highway maintenance project, the Slope Assist system reduced blade tip wear by 25% by preventing the cutting edge from being forced into the subgrade during transitions. By automating the micro-adjustments required to keep the blade parallel to the design surface, Caterpillar is allowing grader operators to achieve high-quality finishes at higher speeds, even in complex terrain.
