Industries, such as construction, agriculture, mining, often employ articulated machines. An articulated machine includes front and rear frames hinged together by a hitch joint for relative pivotal movement. When one of the frames is moved relative to the other, the articulated machine turns. Sometimes, such articulated machines may over-articulate, i.e., turn at the hitch joint such that the front and rear frames contact each other. Frame contact can occur if rimpull pushing the machine exceeds the machine's steering torque capability. For example, torque generated around the hitch when rimpull pushes the machine into a pile may contribute to the machine exceeding the machine's steering torque capability and can forcibly articulate the machine causing the frames to make contact. Frequent or excessive contact between the front and rear frames is undesirable as such contact may damage the machine, e.g., frame damage, bent axles, breakage of hydraulic lines, etc. Typically a steering system of the machine, alone, may not be capable of preventing over-articulation. In an effort to address over-articulation, an articulated machine may have stops on its frame structure to limit the articulation angle. These stops may prevent the front and rear frames from directly contacting each other when the machine over articulates. However, even frequent or excessive contact of the stops can cause damage to the machine.
U.S. Pat. No. 6,631,320, hereinafter referred as the '320 patent, describes an electronic traction control system for work machines having an articulated chassis made up of a front frame and a rear frame interconnected by an articulation joint. The electronic traction control system includes an electronic controller module to receive an articulation angle signal from an articulation sensor and a wheel speed signal from a wheel speed sensor. The electronic traction control system calculates a desired wheel speed responsive to the articulation angle signal and the wheel speed signals, and selectively applies brakes until the measured wheel speed is equal to the desired wheel speed. The electronic traction control system of the '320 patent provides traction control for an articulated machine; however, such electronic traction control system is not described in the '320 patent as eliminating or reducing frame contact in the articulated machine.