When Caterpillar upgraded its M series motor graders last year, safety was not highlighted. But it was included in many facets of the design, which featured over 100 patents.
One of the most unusual aspects was replacing the steering wheel and other controls with a joystick, reducing operator motion by 78%. Sharp turns became easier, but that capability also increased the chance that wheels could turn too quickly and tip the vehicle.
Electronic control modules (ECMs) addressed that threat. “The ECM looks at the ground speed and calculates a maximum steering angle to protect the machine and the operator,” said Howard Woolard, Commercial Manager at Caterpillar’s Motor Grader Group.
The new grader family also employs backup cameras, which were needed partially because of the hardware needed to cut engine emissions. “We would prefer not to use cameras. But as emissions regulations increase what we put inside the engine compartment, the cover height rises and impacts sight lines, so we need cameras,” said Woolard.
Other changes bring benefits to those who need to look under those engine covers. “Hydraulic fans operate only when they’re needed, eliminating a lot of noise and saving energy. But they also eliminate worries about getting fingers caught in belts,” said Woolard.
Sophisticated links between seats and transmissions also help reduce accidents, using presence switches to prevent accidental operation when the driver is not in the seat. These sensors preclude operators from pushing the joystick into a drive position while climbing into the cab. But they give them the freedom to move during operations.
“The M series operator-presence system reads the transmission speed so that if the operator stands up and isn’t in the seat, it won’t [activate] the parking brake and send him into the windshield,“ said Wade Porter, Marketing Supervisor at Caterpillar’s Motor Grader Group.