Caterpillar Inc.

Kevin Jay Lueschow

Brian Dean Kuras

Michael G Cronin

Ken L Stratton

James C Barton

Kenneth Lee Stratton

Craig L Koehrsen

Stephen V Lunzman

Daniel E Henderson

Karl W Kleimenhagen

Joel L Peterson

Giles Kent Sorrells

Jerry D Marr

Charles Earl Rose

Ronald K Scott

Jeffrey J Simmons

Thomas G Hayes

Jody M Drake

Dugan Um

A system for monitoring an exposure of a machine operator to machine vibration is provided. The system includes an operator safety restraint. The system also includes at least one vibration sensor on the safety restraint and configured to generate a signal indicative of operator exposure to machine vibration. The system further includes a controller configured to receive the signal and configured to determine an amount of vibration exposure of the machine operator based on the signal.

Monitoring system for machine vibration

The present invention provides a method and apparatus configured to perform relative load compensation for a payload measurement system of a machine. The machine has at least one cylinder for elevating a payload carrier. The cylinder is connected to a fluid circuit having an actuating fluid. The payload measurement system is calibrated. Then a load of unknown weight is lifted. To determine the weight of this load, the system determines an uncompensated payload weight as a function of sensed pressure values of the actuating fluid. Temperature of the actuating fluid is sensed at the time of calibration and at a time of lift and the difference is scaled. A payload weight is determined as a function of the scaled temperature and the uncompensated payload weight.

Method and apparatus for performing temperature compensation for a payload measurement system

Operating a vehicle with a faulty strut can cause serious consequences. The present disclosure includes a method of detecting a fault within a strut during operation of a vehicle. Pressure within the strut is sensed, and a magnitude of asymmetry within a plurality of the sensed pressures is determined. A faulty strut (e.g. overcharged or collapsed) is indicated when the magnitude of asymmetry is outside of a predetermined range of asymmetry.

Method for indicating a faulty strut and vehicle using same

An abnormal lifting cycle of a work machine lift component can be indicative of operator error and/or a fault within a lift component coupler. The present disclosure includes a method of detecting a fault for a lift component coupler of a work machine. Pressure within at least one hydraulic cylinder of the coupler is sensed during at least a portion of a lifting cycle of the lift component. A condition of the lifting cycle can be determined by detecting a magnitude of asymmetry within a plurality of the sensed pressures. An abnormal condition of the lifting cycle is indicated if the magnitude of the asymmetry of the plurality of the sensed pressures is outside of a predetermined range of asymmetry.

Method for detecting an abnormal lifting cycle and work machine using same

A system for validating a payload weight measurement for a machine includes a pressure sensor configured to generate a pressure signal indicative of an actuating fluid pressure associated with a fluid cylinder operatively coupled to a work implement of the machine. An extension sensor is configured to generate an extension signal indicative of an extension of the fluid cylinder. The system also includes a controller configured to monitor the pressure signal and the extension signal to determine a plurality of actuating fluid pressure values and corresponding extension values associated with the fluid cylinder while lifting a payload of unknown weight with the work implement. The controller is also configured to compare the plurality of actuating fluid pressure values and the corresponding extension values to at least one predetermined pressure versus extension curve and to determine whether an accurate weight value may be assigned to the payload based on the comparison of the plurality of actuating fluid pressure values and the corresponding extension values to the at least one predetermined pressure versus extension curve.

System for detecting an incorrect payload lift

A method and apparatus is provided for calibrating a payload monitor of a work machine. Altering the load carrying body of a work machine can adversely impact the accuracy of a payload monitor. The present invention provides a calibrating technique using an alternate coefficient that is programmed into the payload monitor. The alternate coefficient is then used by the payload monitor.

Payload monitor having distribution coefficient

The present invention is configured to determine the weight of a payload of a mobile machine. When the machine is in motion, a force characteristic of the machine is compared with a force characteristic threshold, or range. The payload determination is based upon the force characteristic comparison, and the pressures sensed in at least one of the struts.

Method and apparatus configured to determine the weight of a machine payload

The present invention provides a method and apparatus configured to perform viscosity compensation for a payload measurement system of a machine. The machine has at least one cylinder for elevating a payload carrier. The cylinder is connected to a fluid circuit having an actuating fluid. A plurality of pressure values of the actuating fluid are sensed during a lifting of a first payload. Then a plurality of pressure values of the actuating fluid are sensed during a lifting of a second payload. In addition a parameter indicative of the fluid viscosity associated with the first and second lift is established. A plurality of pressure values of the actuating fluid are sensed during a lifting of a third payload, and a parameter indicative of the viscosity of the actuating fluid associated with the third lift is established. A payload weight of the third payload is then determined in response to the viscosity indicative parameters, and the sensed plurality of actuating fluid pressure values.

Method and apparatus configured to perform viscosity compensation for a payload measurement system

An apparatus for controlling load on an engine is disclosed. The apparatus includes a continuously variable transmission driven by the engine. The apparatus further includes an engine speed sensor being adapted to sense the output speed of the engine and produce an engine speed signal indicative of the engine output speed and a travel speed sensor being adapted to sense the travel speed of the machine and produce a travel speed signal indicative of the machine travel speed. The apparatus yet further includes an electronic controller operable to compare the engine speed signal to an underspeed value and produce an integral error signal indicative of the difference between the engine speed signal and the underspeed value, supply an integral gain value based on the machine travel speed, modify the integral error signal through a proportional plus integral feedback controller to produce an underspeed request signal, and produce a command signal based on the underspeed request signal. The command signal is used to control the transmission ratio of the continuously variable transmission so as to control the load on the engine. A method for controlling a load on an engine associated with a continuously variable transmission is also disclosed.

Underspeed control system for a hydromechanical drive system and method of operating same

A control apparatus for a continuously variable transmission is disclosed. The control apparatus includes a transmission speed sensor which generates an actual velocity signal in response measuring speed of an output shaft of the continuously variable transmission. The control apparatus further includes a first input device, or speed pedal, which is positionable in one of an infinite number of positions and generates a desired velocity signal corresponding to the position of the speed pedal. The control apparatus yet further includes a controller operable to receive the desired velocity signal, receive the actual velocity signal, calculate a commanded acceleration a,, and generate a commanded velocity V,based on the desired velocity signal, a jerk value j, and the commanded acceleration a,. A method of controlling a continuously variable transmission is also disclosed.

Method and apparatus for generating velocity commands for a continuously variable transmission

A control apparatus for a continuously variable transmission is disclosed. The control apparatus includes a transmission speed sensor which generates actual velocity signals in response measuring a speed of an output shaft of the continuously variable transmission. The control apparatus further includes a first input device which is positionable in one of a number of positions and generates a desired velocity signal corresponding to the one of the number of positions. The control apparatus yet further includes a controller operable to receive the desired velocity signals, receive the actual velocity signals, determine when rapid changes in the desired velocity are requested by an operator, and generate a commanded acceleration and a commanded velocity based on a jerk value which exceeds a predetermined jerk limit in response to the rapid changes in the desired velocity. A method of controlling a continuously variable transmission is also disclosed.

Method and apparatus for generating velocity commands in response to

An apparatus for controlling an electrohydraulic system of a work machine having an engine that drives a variable displacement pump is disclosed. The apparatus includes a pump displacement setting device that produces a pump command signal, a pressure sensor that detects the fluid pressure associated with the variable displacement pump and produces a pressure signal, and an engine speed sensor that detects the speed of the engine and produce an engine speed signal. A microprocessor computes the torque demand on the engine in response to the desired pump displacement, determines a torque limit associated with the engine in response to the engine speed, and responsively modifies the pump command signal to limit the engine torque.

Torque limiting control system for a hydraulic work machine

A method for calculating a volume between previous and current site surfaces is provided. The site surfaces are represented by a series of surface elevations. The method includes the steps of determining previous surface elevations; traversing the site with a work machine and determining current surface elevations; and calculating a volume difference between the current surface and the previous surface as a function of the previous surface elevations and the current surface elevations.

Method for determining the volume between previous and current site

An automatic lift and tip coordination system for use in connection with an off-highway vehicle having an implement causes an automatic adjustment to the implement lift actuators in response to an operator change in the implement tip angle so that the implement height remains constant.

Automatic lift and tip coordination control system and method of using

An off-highway vehicle having an earth moving implement has a tilt function associated with the implement. For example, a bulldozer has a tilt function associated with the bulldozer blade. The vehicle has a processor adapted to receive a position signal from a position sensor associated with the tilt function of the implement. The operator engages a switch to activate an automatic tilt function. A selector switch is provided so that the operator can select between a plurality of pre-set blade angles. The selector switch outputs a target position signal associated with a pre-set angle to the processor. The processor automatically calculates a command signal for the tilt function based on the difference between the position signal and the target position signal. The processor issues the command signal to the tilt function causing the tilt function to move the implement to the pre-set angle associated with the switch position.

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Elmwood, IL, United States of America

Kevin Jay Lueschow