Abstract: A system includes a vehicle controller which includes a memory configured to store instructions and one or more processors. The vehicle controller is configured to set a fuel efficient operation mode. The fuel efficient operation mode includes setting a commanded engine speed to a nominal engine speed located within a range of optimal fuel efficiency engine speeds of a brake specific fuel consumption map. The fuel efficient operation mode also includes instructing an engine to operate at the commanded engine speed. The fuel efficient operation mode also includes determining a monitored engine speed. The fuel efficient operation mode also includes adjusting a commanded pump displacement in response to the monitored engine speed exceeding the range of optimal fuel efficiency engine speeds. The fuel efficient operation mode also includes instructing a hydraulic pump to operate at the commanded pump displacement.

Abstract: A method for executing straight tracking control may include receiving an input command(s) associated with controlling the operation of a first-side drive system and/or a second-side drive system of a hydrostatic transmission of a work vehicle to drive the vehicle along a straight path. The method may also include receiving first and second speed signals associated with the output speeds of the drive systems, and modifying the first speed signal or the second speed signal based on a speed scaling factor to generate a corrected speed signal. In addition, the method may include determining an adjusted control command for controlling the operation of the hydrostatic transmission as a function of the input command(s) and a control output determined based on the corrected speed signal. Further, the method may include controlling the operation of the hydrostatic transmission based at least in part on the adjusted control command.

Abstract: A method for executing straight tracking control may include receiving an input command(s) associated with controlling the operation of a first-side drive system and/or a second-side drive system of a hydrostatic transmission of a work vehicle to drive the vehicle along a straight path. The method may also include receiving first and second speed signals associated with the output speeds of the drive systems, and modifying the first speed signal or the second speed signal based on a speed scaling factor to generate a corrected speed signal. In addition, the method may include determining an adjusted control command for controlling the operation of the hydrostatic transmission as a function of the input command(s) and a control output determined based on the corrected speed signal. Further, the method may include controlling the operation of the hydrostatic transmission based at least in part on the adjusted control command.

Abstract: A method for controlling engagement of a power take-off (PTO) clutch of a work vehicle may generally include transmitting, by a computing device, a control signal associated with initiating engagement of the PTO clutch, determining a clutch slippage energy generated during engagement of the PTO clutch due to clutch slippage and, while the PTO clutch is getting engaged, calculating a clutch engagement time remaining until engagement of the PTO clutch is completed based on the clutch slippage energy and a maximum clutch engagement energy associated with the PTO clutch. In addition, the method may include determining a torque command for controlling engagement of the PTO clutch as a function of the remaining clutch engagement time and controlling the engagement of the PTO clutch based on the torque command.

Abstract: A method for controlling power takeoff (PTO) clutch engagement includes determining an output clutch speed, adjusting a clutch current at a predetermined rate, estimating an inertial load of a PTO implement and adjusting the clutch current for one or more times at a time interval, and selecting a clutch control algorithm configured for the inertial load of the PTO implement.

Abstract: A method for controlling PTO clutch engagement includes determining a first change in clutch speed based on an inertial load of a PTO implement. The method also includes determining a second change in clutch speed based on a threshold amount of energy of a PTO clutch. The method further includes determining a third change in clutch speed between the first change in clutch speed and the second change in clutch speed. The method also includes adjusting a clutch current based on the third change in clutch speed.

Abstract: A vehicle including a shaft, a park brake connected to the shaft and configured to retard a rotation of the shaft, and a park brake prognosis system associated with the shaft and the park brake. The park brake prognosis system includes a controller that is configured to calculate a status of the park brake dependent on a park brake energy of at least one engagement of the park brake and a first sensor operably coupled to the controller and the shaft. The first sensor is configured to provide a speed of the shaft. The park brake prognosis system also includes a second sensor operably coupled to the controller and the shaft. The second sensor is configured to provide an instantaneous torque of the shaft.

Abstract: An agricultural vehicle includes an engine, a transmission driven by the engine, and a controller. The controller, in operation, adjusts a gear ratio of the transmission using an algorithm. The algorithm, in operation, performs the following steps: reduce a torque capacity of a first offgoing clutch of the transmission to a first torque target, reduce the torque capacity of the first offgoing clutch to a second torque target while adjusting the torque capacity of a first oncoming clutch of the transmission to a third torque target, such that the gear ratio of the transmission is modified in a first direction, and increase the torque capacity of the first oncoming clutch to a desired torque capacity.

Abstract: A method for controlling engagement of a power take-off (PTO) clutch of a work vehicle may generally include transmitting, by a computing device, a control signal associated with initiating engagement of the PTO clutch, determining a clutch slippage energy generated during engagement of the PTO clutch due to clutch slippage and, while the PTO clutch is getting engaged, calculating a clutch engagement time remaining until engagement of the PTO clutch is completed based on the clutch slippage energy and a maximum clutch engagement energy associated with the PTO clutch. In addition, the method may include determining a torque command for controlling engagement of the PTO clutch as a function of the remaining clutch engagement time and controlling the engagement of the PTO clutch based on the torque command.

Abstract: A ramping subsystem of a control system for a dual path electronically controlled hydrostatic transmission is used to modify the commanded rate of change of pump and motor acceleration, deceleration and direction change command (performed to command machine motion from forward to reverse or vice versa) in order to achieve desired machine performance and operator feel. Pump and motor acceleration, deceleration and direction change command rates are then further modified using scaling tables based on selected maximum machine speed using operator input device.

Abstract: A method for controlling power takeoff (PTO) clutch engagement includes determining an output clutch speed, adjusting a clutch current at a predetermined rate, estimating an inertial load of a PTO implement and adjusting the clutch current for one or more times at a time interval, and selecting a clutch control algorithm configured for the inertial load of the PTO implement.

Abstract: An agricultural vehicle includes an engine, a transmission driven by the engine, and a controller. The controller, in operation, adjusts a gear ratio of the transmission using an algorithm. The algorithm, in operation, performs the following steps: reduce a torque capacity of a first offgoing clutch of the transmission to a first torque target, reduce the torque capacity of the first offgoing clutch to a second torque target while adjusting the torque capacity of a first oncoming clutch of the transmission to a third torque target, such that the gear ratio of the transmission is modified in a first direction, and increase the torque capacity of the first oncoming clutch to a desired torque capacity.

Abstract: A method for controlling PTO clutch engagement includes determining a first change in clutch speed based on an inertial load of a PTO implement. The method also includes determining a second change in clutch speed based on a threshold amount of energy of a PTO clutch. The method further includes determining a third change in clutch speed between the first change in clutch speed and the second change in clutch speed. The method also includes adjusting a clutch current based on the third change in clutch speed.

Abstract: The straight tracking control system can use a control method to achieve a desired straight motion of a machine with a dual path electronically controlled hydrostatic transmission. In the control method, the first drive system, e.g., the left or right drive system, pump solenoid current can be modified based on first and second drive system velocity feedback when the machine is commanded to move in a straight line path in the forward or reverse direction. A memory latching concept is used to latch the straight tracking factor at the initiation of and during the turn so the same straight tracking factor is used throughout the turn. The straight tracking factor is unlatched at the completion of a turn after a specific time delay and a new straight tracking factor can be calculated. The straight tracking method also utilizes transmission fluid temperature and utilizes additional fluid reserve in order to maintain straight machine movement.

Abstract: A control system for a machine with a dual path electronically controlled hydrostatic transmission is used to achieve a desired performance and a desired operator feel while performing all of the machine operations. The control system includes pump and motor displacement resolvers, command resolver, ramping blocks, pump and motor steering resolvers, engine load management and a straight tracking subsystem.

Abstract: A method of shifting a transmission of a vehicle. The method includes the steps of: initiating a shift from a first gear to a second gear in the transmission; disengaging a first clutch associated with the first gear; engaging a second clutch associated with the second gear; and actively modifying a pump displacement and/or a motor displacement while the disengaging step or the engaging step are carried out. The motor is drivingly coupled to the transmission.

Abstract: A method of shifting a transmission of a vehicle. The method includes the steps of: initiating a shift from a first gear to a second gear in the transmission; disengaging a first clutch associated with the first gear; engaging a second clutch associated with the second gear; and actively modifying a pump displacement and/or a motor displacement while the disengaging step or the engaging step are carried out. The motor is drivingly coupled to the transmission.

Abstract: A method of managing engine load by adjusting the pump and motor displacements of a dual path electronically controlled hydrostatic transmission utilizes the difference between the reference and actual engine speeds, the temperature of the working fluid for the dual path electronically controlled hydrostatic transmission, the engine governor droop value, the vehicle speed and lookup tables to determine pump and motor command adjustment factors associated with specific engine loading conditions.

Abstract: A method of managing engine load by adjusting the pump and motor displacements of a dual path electronically controlled hydrostatic transmission utilizes the difference between the reference and actual engine speeds, the temperature of the working fluid for the dual path electronically controlled hydrostatic transmission, the engine governor droop value, the vehicle speed and lookup tables to determine pump and motor command adjustment factors associated with specific engine loading conditions.

Abstract: The straight tracking control system can use a control method to achieve a desired straight motion of a machine with a dual path electronically controlled hydrostatic transmission. In the control method, the first drive system, e.g., the left or right drive system, pump solenoid current can be modified based on first and second drive system velocity feedback when the machine is commanded to move in a straight line path in the forward or reverse direction. A memory latching concept is used to latch the straight tracking factor at the initiation of and during the turn so the same straight tracking factor is used throughout the turn. The straight tracking factor is unlatched at the completion of a turn after a specific time delay and a new straight tracking factor can be calculated. The straight tracking method also utilizes transmission fluid temperature and utilizes additional fluid reserve in order to maintain straight machine movement.