Abstract:
A transmission assembly driven by an engine is disclosed. The transmission assembly includes a hydrostatic transmission having a variable displacement hydraulic pump and a hydraulic motor, a mechanical transmission coupled to the hydrostatic transmission for selecting a first gear range and a second gear range, and a controller for receiving operator inputs and generating a displacement command operable to control a displacement of the variable displacement pump. The controller determines the actual displacement. The controller determines a displacement shift level from the actual displacement. The controller executes a shift from the first gear range to the second gear range when the actual displacement reaches displacement shift level. A method of controlling a transmission assembly is also disclosed.
Abstract:
A machine is described that includes an engine, a multi-clutch transmission and a controller. The controller is configured with computer-executable instructions for managing operation of the multi-clutch transmission to avoid autoengagement of a disengaged clutch. The computer-executable instructions configure the controller to receive sensor signals indicative of current operating status of the machine; determine, based upon the sensor signals, a configured minimum engine speed needed to avoid autoengagement of the disengaged clutch; and conditionally increase an engine speed based upon a comparison of the configured minimum engine speed and a sensed current engine speed. The machine includes a continuously variable transmission coupled to the multi-clutch transmission, and the controller is configured to adjust the continuously variable transmission ratio to counter the engine speed increase and thus maintain a current clutch output speed when increasing the engine speed to avoid autoengagement of a disengaged clutch.
Abstract:
A system and method for variator control employs positively directed electronic make-up and flushing relief valves for more precise torque control of a hydraulic variator, especially during torque reversal, as well as improved cold weather operation. This can improve machine response during periods of severe torque change. The ability to more tightly control variator torque allows more precise torque management algorithms for power control and engine matching purposes. Moreover, the ability to positively control venting of the hydraulic circuit for purposes of fluid cooling allows for more consistent machine response regardless of ambient temperature.
Abstract:
A variator torque control system adjusts a variator output so that the actual output torque of the variator closely matches an expected output torque. In an example, pressure values of an existing torque control map are supplemented in real time with calculated pressure supplement values based on the current operation of the variator. The pressure supplement value for each mapped pressure value may be derived based on a prior application of the same or another map value.
Abstract:
A system and method for optimizing machine performance using speed shaping in a machine having an engine and a drivetrain implementing engine underspeed module receives a throttle command requesting an increase in engine speed and transmits the throttle command to the engine. If the requested increase exceeds a predetermined function, the predetermined function is forwarded to the engine underspeed module as a speed standard. The engine underspeed module determines whether the actual engine speed attained by the engine is less than the speed standard by more than a predetermined gap value and, if so, reduces the power required by the drivetrain to avoid lugging of the engine.
Abstract:
A method is provided for controlling braking in a vehicle having a motor and a brake. The method includes sensing an actual operating parameter of the motor and receiving a desired operating parameter of the motor. The motor is controlled based on the actual operating parameter and the desired operating parameter of the motor. The brake is controlled based on the actual operating parameter and the desired operating parameter of the motor and an output from the motor control.
Abstract:
A variator torque control system and method utilize a hydraulic actuator to control the variator output via a torque control map, wherein the values of the torque control map are evaluated and modified during use of the map to improve map accuracy. In an example, errors in the map are evaluated to determine whether a system fault has occurred.
Abstract:
An electric drive system has a power source and a generator operatively connected to the power source. The generator is configured to produce a power output. The electric drive system also has at least one capacitor configured to store a supply of power. The electric drive system further has a common bus configured to direct the power output to the capacitor. The electric drive system also has at least one motor configured to receive power from the common bus. The electric drive system additionally has a controller in communication with the at least one motor and the generator. The controller is configured to receive at least one input associated with the motor, to determine a requested motor power as a function of the at least one input, and to operate the generator to produce the requested motor power.
Abstract:
A method of conditioning a signal being communicated between a system to be controlled and a controller may include monitoring an actual output signal and conditioning the actual output signal. The method also includes determining the difference between the actual output signal and the condition signal and causing the actual output signal to be filtered based on the relationship between the difference between the actual output signal and the conditioned signal.
Abstract:
A method of dissipating power in a propelled machine having an electric drive includes converting undesired power to electric power by the electric drive, and driving an internal combustion engine with at least a portion of the electric power prior to substantially dissipating power with any other power dissipating device.