Abstract: A power system for a machine is provided. The power system includes an operator interface for entering an operator command relating to one or more functions of the machine. The power system includes a hydraulic pump and an engine configured to provide power to the hydraulic device. A controller is in communication with the operator interface, the hydraulic device and the engine. The controller is configured to consider operator skill level information relating to a skill level of the operator of the machine and to determine at least one desired power system operating parameter based on the operator command and the operator skill level information and to adjust at least one of the hydraulic pump and the engine based on the desired power system operating parameter.

Abstract: A control system for a machine having a cylinder and an accessory is disclosed. The control system may include a pump configured to provide fluid to the cylinder and the accessory, and a controller operatively connected to the pump. The controller may be configured to operate the pump to provide a primary flow to the cylinder at up to a predetermined maximum level for the cylinder. The predetermined maximum level for the cylinder may be less than a maximum flow capability of the pump. The controller may also be configured to operate the pump to provide a secondary flow to the accessory utilizing a remaining fluid.

Abstract: Method of controlling multiple variable displacement hydraulic pumps determined relative to operator commands. If non-second-pump-dominated command, a respective adjusted displacement request is determined based upon the lesser of the operator requested torque limited displacement and an adjusted torque limited displacement that calculated based upon and the torque limited displacement of the respective pump and a scaling factor calculated based upon the first relief valve set pressure and respective pump pressure. If second-pump-dominated command, the set pressure of a relief valve associated with one of the pumps is instead utilized in calculating the scaling factor in the above strategy.

Abstract: A system and method involves a machine that powertrain including a continuously variable transmission (CVT) and a machine speed sensor to determine a measured machine speed. The machine also includes a controller in communication with the CVT and the speed sensor. The controller may include a table relating the measured machine speed to a plurality of virtual gear ratios associated with the CVT. The controller is configured to determine a calculated virtual gear ratio using the table and, if desired, may display the calculated virtual gear ratio on a visual display.

Abstract: Method of controlling multiple variable displacement hydraulic pumps determined relative to operator commands. If non-second-pump-dominated command, a respective adjusted displacement request is determined based upon the lesser of the operator requested torque limited displacement and an adjusted torque limited displacement that calculated based upon and the torque limited displacement of the respective pump and a scaling factor calculated based upon the first relief valve set pressure and respective pump pressure. If second-pump-dominated command, the set pressure of a relief valve associated with one of the pumps is instead utilized in calculating the scaling factor in the above strategy.

Abstract: A power system for a machine is provided. The power system includes an operator interface for entering an operator command relating to one or more functions of the machine. The power system includes a hydraulic pump and an engine configured to provide power to the hydraulic device. A controller is in communication with the operator interface, the hydraulic device and the engine. The controller is configured to consider operator skill level information relating to a skill level of the operator of the machine and to determine at least one desired power system operating parameter based on the operator command and the operator skill level information and to adjust at least one of the hydraulic pump and the engine based on the desired power system operating parameter.

Abstract: A machine includes an engine and an engine cooling system, which is associated with and configured to remove heat from the engine. A transmission is connected to the engine and configured to transmit engine power from the engine to a driven load. The transmission controls an amount of engine power transmitted to the driven load in response to a transmission command signal. A controller associated with the engine and the transmission provides the transmission control signal. The controller is disposed to determine an engine operating condition, determine a transmission operating condition, and adjust the transmission command signal to reduce the amount of engine power transmitted to the driven load when the engine operating condition indicates that the engine cooling system removes insufficient heat from the engine.

Abstract: A method regulates the torque output and/or speed output of a continuously variable transmission (CVT) in a manner that may simulate a clutch. The CVT may be incorporated in a machine and maybe operatively coupled to a power source and to a propulsion device. The method utilizes an unaltered torque-to-speed curve that relates the torque output to the speed output of the CVT. The method may receive an operator input signal indicating a desire to change operation of the machine. The torque-to-speed curve may be shifted in response to the operator input signal to limit the torque output available. In an aspect, an under-run curve may be applied to the torque-to-speed curve, the under-run curve corresponding to a target speed. The operator input signal may also shift the under-run curve to reduce the target speed.

Abstract: A system and method involves a machine having a power train including a continuously variable transmission (CVT) associated with a plurality of virtual gear ratios. To shift between the plurality of virtual gear ratios, the machine may include an operator input device that may be movable between a plurality of distinct positions. A first position may be associated with a neutral position in which no shifting of virtual gear ratios occurs. A second position of the operator input device may be associated with a first incremental rate for shifting between the virtual gear ratios. A third position may be associated with a second incremental rate for shifting between the virtual gear ratios which is different than the first incremental rate.

Abstract: A method of controlling a transmission (100) for a machine is disclosed. The transmission includes a variator (104). The transmission is operated in a first operating range (301). It is determined whether a current speed ratio is within a first predetermined range of a speed ratio associated with a first synchronous point (304) lying between the first operating range (301) and the second operating range (302). A desired speed ratio is determined and it is determined if the desired speed ratio is within a second predetermined range of the speed ratio. A shift between the first and second operating ranges (301, 302) is prevented and the variator (104) is controlled to hold the current speed ratio if the desired speed ratio is within the second predetermined range or the rate of acceleration of the machine is below the threshold acceleration.

Abstract: A machine may include a continuously variable transmission (CVT) operatively coupled to a power source. A virtual gear ratio may be selected from a plurality of virtual gear ratios associated with the CVT. A power source speed may be locked between a minimum power source limit and a maximum power source limit that are associated with the selected virtual gear ratio. If the virtual gear ratio is changed, a controller including one or more control maps may compare the power source speed as locked to the minimum power source limit and the maximum power source limit as they relate to the newly selected virtual gear ratio. If power source speed is outside the minimum or maximum power source limits, the method may limit the power source speed. In some embodiments, the minimum and/or maximum power source limits may vary with respect to the plurality of virtual gear ratios.

Abstract: A method controls the power-transmission in a machine having a continuously variable transmission (CVT) and a power source operatively coupled together in a powertrain. The method regulates operation of the CVT with a retarding power limit in order to limit the amount of retarding power transferable from the powertrain to the power source. The retarding power may be utilized to decelerate or decrease the speed of the machine. The method may register an operator input signal indicative of a deceleration event from a plurality of possible deceleration events. The deceleration event is compared to a lookup table to determine if the retarding power limit should be adjusted. The method may adjust the retarding power limit in accordance with the comparison.

Abstract: A machine includes an engine and an engine cooling system, which is associated with and configured to remove heat from the engine. A transmission is connected to the engine and configured to transmit engine power from the engine to a driven load. The transmission controls an amount of engine power transmitted to the driven load in response to a transmission command signal. A controller associated with the engine and the transmission provides the transmission control signal. The controller is disposed to determine an engine operating condition, determine a transmission operating condition, and adjust the transmission command signal to reduce the amount of engine power transmitted to the driven load when the engine operating condition indicates that the engine cooling system removes insufficient heat from the engine.

Abstract: A system and method involves a machine that powertrain including a continuously variable transmission (CVT) and a machine speed sensor to determine a measured machine speed. The machine also includes a controller in communication with the CVT and the speed sensor. The controller may include a table relating the measured machine speed to a plurality of virtual gear ratios associated with the CVT. The controller is configured to determine a calculated virtual gear ratio using the table and, if desired, may display the calculated virtual gear ratio on a visual display.

Abstract: A method regulates the torque output and/or speed output of a continuously variable transmission (CVT) in a manner that may simulate a clutch. The CVT may be incorporated in a machine and maybe operatively coupled to a power source and to a propulsion device. The method utilizes an unaltered torque-to-speed curve that relates the torque output to the speed output of the CVT. The method may receive an operator input signal indicating a desire to change operation of the machine. The torque-to-speed curve may be shifted in response to the operator input signal to limit the torque output available. In an aspect, an under-run curve may be applied to the torque-to-speed curve, the under-run curve corresponding to a target speed. The operator input signal may also shift the under-run curve to reduce the target speed.

Abstract: A system and method involves a machine having a power train including a continuously variable transmission (CVT) associated with a plurality of virtual gear ratios. To shift between the plurality of virtual gear ratios, the machine may include an operator input device that may be movable between a plurality of distinct positions. A first position may be associated with a neutral position in which no shifting of virtual gear ratios occurs. A second position of the operator input device may be associated with a first incremental rate for shifting between the virtual gear ratios. A third position may be associated with a second incremental rate for shifting between the virtual gear ratios which is different than the first incremental rate.

Abstract: A method controls the power-transmission in a machine having a continuously variable transmission (CVT) and a power source operatively coupled together in a powertrain. The method regulates operation of the CVT with a retarding power limit in order to limit the amount of retarding power transferable from the powertrain to the power source. The retarding power may be utilized to decelerate or decrease the speed of the machine. The method may register an operator input signal indicative of a deceleration event from a plurality of possible deceleration events. The deceleration event is compared to a lookup table to determine if the retarding power limit should be adjusted. The method may adjust the retarding power limit in accordance with the comparison.

Abstract: A machine may include a continuously variable transmission (CVT) operatively coupled to a power source. A virtual gear ratio may be selected from a plurality of virtual gear ratios associated with the CVT. A power source speed may be locked between a minimum power source limit and a maximum power source limit that are associated with the selected virtual gear ratio. If the virtual gear ratio is changed, a controller including one or more control maps may compare the power source speed as locked to the minimum power source limit and the maximum power source limit as they relate to the newly selected virtual gear ratio. If power source speed is outside the minimum or maximum power source limits, the method may limit the power source speed. In some embodiments, the minimum and/or maximum power source limits may vary with respect to the plurality of virtual gear ratios.

Abstract: A method of controlling a transmission (100) for a machine is disclosed. The transmission includes a variator (104). The transmission is operated in a first operating range (301). It is determined whether a current speed ratio is within a first predetermined range of a speed ratio associated with a first synchronous point (304) lying between the first operating range (301) and the second operating range (302). A desired speed ratio is determined and it is determined if the desired speed ratio is within a second predetermined range of the speed ratio. A shift between the first and second operating ranges (301, 302) is prevented and the variator (104) is controlled to hold the current speed ratio if the desired speed ratio is within the second predetermined range or the rate of acceleration of the machine is below the threshold acceleration.

Abstract: A system and method of controlling the speed of a machine having a continuously variable transmission (CVT) operatively coupled to a power source. A plurality of selectable virtual gear ratios can be associated with the CVT. The machine may include an operator input device that may generate a operator input signal indicative of a desired adjustment in the ground speed. The operator input signal may be converted to a CVT speed command and to a power source speed command that are communicated to the CVT and the power source, respectively. The CVT adjusts the machine speed in accordance with the CVT speed command, while the power source adjusts its speed in accordance with the power source speed command, so that operation of the power source is substantially independent of operator of the CVT.