Off-road Fork Lift
This off-road fork lift is used to support large building construction projects. The forks can be loaded with up to 11,000 pounds of building materials and raised to a height of 57 feet. In its initial configuration, the fork leveling function utilized only on/off controls which resulted in rough, abrupt motions. The engine was controlled independently of the boom functions so engine stalls could occur, which created an unsafe condition. Further, since the boom was manually controlled, the forks could easily deviate from a level orientation, which could result in dropped materials.
GS Global Resources (GSGR) significantly improved the safety and operation of this fork lift by implementing a CAN-based total machine control system. This total machine control system includes proportional control which allows precise movement of the boom lift and extend. The master controller, along with a custom program, allow the forks to move in a coordinated manner parallel to the ground, or vertically along the wall of a building. A CAN joystick is used to control the boom movements. Rotary encoders and linear transducers are used to provide closed loop feedback to a master controller. In addition, the control system now controls engine RPM so that adequate horsepower is always available to operate the boom under varying loads.