Abstract: A hitch control system controls a vehicle hitch to which implements can be attached. The hitch control system includes a spring-centered primary command lever which is manually moveable from a centered position to deflected positions, and which automatically returns to the centered position when released from a deflected position. A control unit generates a hitch command signal in part as a function of the lever position. The control unit has a closed-loop control mode wherein the valve command signal is generated in response to parameter, such as position and draft force, and the hitch command signal. The control unit moves the hitch in a step-wise manner by a predetermined amount in response to momentary deflection of the command lever to one of the deflected positions, and the amount of hitch movement is independent of an amount and duration of deflection of the command lever if the duration is not more than a predetermined duration.

Abstract: A control system is provided for a tracked vehicle drive/steering system having an engine driven hydraulic steering pump which drives a hydraulic steering motor. The steering pump is responsive to steering control signals representing a status of an operator manipulated steering wheel. The steering motor provides an input to a differential track drive mechanism which responds to manipulation of the steering wheel and drives left and right tracks to turn the vehicle. The control system includes a control unit which receives signals from an engine speed sensor, a steering motor rotation speed and direction sensor, and the steering control signals. The control unit, when the steering control signals indicate that the steering wheel is turned in a direction opposite to a direction of rotation of the steering motor, generating and saving a first ratio value representing a ratio of the motor speed to the pump speed.

Abstract: A vehicle/implement hitch control system is responsive to a wheel slip signal indicative of the slippage of the driven wheels of the vehicle. The control system generates an integrated slip signal using an integration function, generates a proportional slip signal using a proportional function, and generates a combined slip signal as a combination of the integrated slip signal and the proportional slip signal. An operator-controllable slip response adjuster generates slip response signals. A hitch control signal is generated as a function of the slip response signal and the combined slip signal, so that the operator can vary the response of the hitch control signal to the integrated slip signal, to a mixture of the integrated slip signal, and to various multiples of the proportional slip signal only.

Abstract: A control system is provided for a tracked vehicle drive/steering system having an engine driven hydraulic steering pump which drives a hydraulic steering motor. The steering pump is responsive to steering control signals representing a status of an operator manipulated steering wheel. The steering motor provides an input to a differential track drive mechanism which responds to manipulation of the steering wheel and drives left and right tracks to turn the vehicle. The control system includes a control unit which receives signals from an engine speed sensor, a steering motor rotation speed and direction sensor, and the steering control signals. The control unit calculates a motor speed threshold value as a function of sensed engine speed and steering control signals, and generates a fault signal as a function of a relationship between the steering motor speed signal and a motor speed threshold value.