Abstract: One disclosed embodiment relates to a propulsion system for a machine. The propulsion system may include a prime mover operatively connected through a continuously variable transmission to a propulsion device. The propulsion system may also include propulsion-system controls that control an operating parameter of the continuously variable transmission, which may include adjusting the operating parameter based on operator input. Controlling the operating parameter may also include determining an adjustment limit for the operating parameter based on one or more operating conditions and applying the adjustment limit to the operating parameter to modify at least one of acceleration and jerk of the machine based on the one or more operating conditions.

Abstract: A sport running estimated value LEVELSP obtained by searching a value on a map prepared in advance based on an average values AGYAVE of lateral accelerations GY of a vehicle and on average values of vehicle speed changes is calculated, and a vehicle speed on a shift map is searched based on the sport running estimated value LEVELSP and an estimated value DA of a vehicle gradient, whereby a downshift vehicle speed VA at which a downshift is implemented is calculated. Then, the downshift is implemented in a case where actuation of a brake is detected, deceleration of the vehicle is a predetermined value or more, and a current vehicle speed is a downshift vehicle speed VA or more. In such a way, running on a meandering road, for which the downshift and a subsequent shift hold should be implemented, is sensed appropriately.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A system includes a pump, accumulator, a sensor which measures line pressure in a fluid circuit, and a controller. The controller plots and calculates respective slopes of first and second sets of measured pressure values from the sensor, calculates a slope ratio, and compares the slope ratio to a threshold. The controller also records the pre-charge pressure as the point of intersection of lines representing the slopes when the ratio exceeds the threshold. A control action is executed when the pre-charge pressure drops below a calibrated minimum threshold. A method includes measuring the pressure values, calculating the respective slopes and the slope ratio, comparing the slope ratio to a ratio threshold, recording the point of intersection of lines representing the slopes as an interpolated pre-charge pressure value when the ratio exceeds the threshold, and executing the control action.

Abstract: A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed.

Abstract: A vehicle is reliably prevented from rolling back during automatic start on a slope or the like. An automatic stop-and-start device includes an engine control unit 10 that automatically stops an engine 2 when a predetermined stop condition is fulfilled and automatically starts the engine 2 when a predetermined start condition is fulfilled; a brake device 3 that imparts a brake force to a vehicle that carries the engine 2; and a brake control unit 16 that holds a brake state produced by the brake device 3 when a predetermined brake hold request condition is fulfilled and releases the brake state produced by the brake device 3 when a predetermined brake release condition is fulfilled. The engine control unit 10 determines whether the brake control unit 16 holds the brake state produced by the brake device 3 and automatically starts the engine 2 when the determination is affirmed.

Abstract: A control device of a continuously variable transmission that controls an input-side thrust force of an input-side variable pulley and an output-side thrust force of an output-side variable pulley to set an actual gear ratio to a target gear ratio and prevent a slip of the transmission belt.

Abstract: A method and system provides a Brake Transmission Shift Interlock Override mode in a vehicle including a shift-by-wire transmission. With power applied and ignition on, a driver will press and hold an override switch for a calibrated time. While the override switch is pressed, the driver presses a non-Park button for another calibrated time. The result will be that the vehicle is placed in the selected range wherein the transmission will not automatically shift to Park upon detecting a triggering event. The driver is able to shift the vehicle from Park, even if an electrical failure prevents the transmission from shifting out of Park. As such the vehicle can be driven until the failure is serviced.

Abstract: A power transmitting apparatus includes a clutch that operates based on pressure of a fed fluid to adjust a mode of power transmission of an engine or/and a motor/generator on a power transmission route, a first driving pump that feeds the fluid to the clutch by being driven in accordance with rotation of the motor/generator, and a second driving pump that feeds the fluid to the clutch by being driven in accordance with electric power, wherein a first engagement unit and a second engagement unit can be caused to engage rapidly or slowly by selecting one of the first driving pump and the second driving pump as a source of the fluid, and when a drive request of the clutch is present and a rotation speed of the motor/generator is lower than a predetermined rotation speed, the first engagement unit and the second engagement unit are caused to engage rapidly by feeding the fluid from the second driving pump.

Abstract: In a controller for a belt-type continuously variable transmission including a hydraulic actuator that changes a groove width of a primary pulley, a hydraulic actuator that changes a groove width of a secondary pulley, and a belt clamping pressure control solenoid that controls the hydraulic pressure supplied to the hydraulic actuator of the secondary pulley, a mechanism calculates a transmission ratio between the primary pulley and the secondary pulley and determines whether or not there is belt slippage based on that calculated transmission ratio, and a mechanism determines normalcy of the belt clamping pressure control solenoid. The input torque when belt slippage has actually occurred, i.e., when a failure has been determined, is used as a condition when performing the normalcy determination.

Abstract: A diagnostic apparatus and a diagnostic method are provided for a belt squeezing force adjusting mechanism of a continuously variable transmission in which a belt is wound around a primary sheave that receives driving force and a secondary sheave that outputs force to a drive line, and which continuously changes the output rotation speed by adjusting the width of the groove the primary sheave and the secondary sheave by shift control. This diagnostic determines, as a precondition, whether a target control value calculated in shift control is in a low region, and performs a diagnostic on the belt squeezing force adjusting mechanism based on the relationship between an actual control value and the target control value during control to reduce a control value when it is determined that the precondition is satisfied. According to this diagnostic apparatus and diagnostic method, an erroneous diagnosis can be prevented so the diagnostic can be performed accurately.

Abstract: A control unit (200) executes fail-safe control that forcibly releases a lockup clutch (15) by activating a fail-safe valve (112), abnormality diagnosis control that determines whether a solenoid valve (DSU) is suffering from a solenoid ON abnormality when the vehicle has started with the fail-safe control executed, and reproduction control that simulatively reproduces, when the vehicle has started without the fail-safe control executed, a condition coinciding with the condition for allowing execution of the abnormality diagnosis control.

Abstract: A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed.

Abstract: An electronic control unit senses an actual shift range of a automatic transmission by executing a range determination operation, which determines the actual shift range of the automatic transmission based on a rotational position of a manual shaft that is sensed with an encoder. The control unit prohibits the execution of the range determination operation throughout a range determination operation prohibiting period, which is a predetermined time period and starts from a time point of starting rotation of the rotor of the electric motor unit toward the target rotational position.

Abstract: A vehicle control device for controlling a vehicle drive apparatus, the vehicle control device configured with a phase determining mechanism that determines the end of the torque phase in a shift operation, and a rotary electrical machine control mechanism that controls the torque of the rotary electrical machine using a variation of input torque. The vehicle control device is also configured with an engagement control mechanism that provides feedback controlling supplied oil pressure to an engagement side element as an engagement element on a side to be engaged after switching of shift speeds so that the rotation speed change rate of the input member becomes the target rotation speed change rate.

Abstract: A torque applying device is provided for applying a driving torque to at least a pair of wheels, and a torque restraining device is provided for restraining the torque created on the wheels to be applied with the torque by the torque applying device. A friction braking device is provided for applying a braking torque to each wheel in response to operation of a brake pedal. An automatic braking control device automatically actuates the friction braking device independently of operation of the brake pedal, to apply the braking torque to each wheel. And, a torque restraining cancellation device is provided for cancelling the torque restraining operation for a time period determined in response to a vehicle speed decreasing state, after a condition for initiating the automatic braking control was fulfilled.

Abstract: A control system may include a polarity determination module, a torque variation module, and a torque sensor diagnostic module. The polarity determination module determines a first polarity of a torque signal that indicates a transmission torque. The torque sensor diagnostic module diagnoses an error of a torque sensor when an detected polarity of the torque signal is opposite from the first polarity. A control system may include a torque variation module and a torque sensor diagnostic module. The torque variation module determines a maximum torque variation during a predetermined diagnostic period based on the torque signal. The torque sensor diagnostic module diagnoses an error of a torque sensor when the maximum torque variation is outside of a torque variation range. The torque variation range is defined by a minimum torque variation threshold and a maximum torque variation threshold.

Abstract: Improved methods for executing a clutch-to-clutch quasi-asynchronous shift in a hybrid transmission, and a hybrid transmission using the same, are presented herein. The method includes: pre-filling the on-coming clutch; determining if the shift is completed using the on-coming or off-going clutch; slipping the off-going clutch first if the shift operation uses the off-going clutch; determining on-coming clutch slip speed and acceleration profiles; determining if the on-coming clutch is filled and whether the slip sign is correct; if using the off-going clutch, locking the on-coming clutch and exhausting the off-going clutch if the on-coming clutch is filled and the slip sign is correct; if using the on-coming clutch, determining whether the on-coming clutch slip is less than a slip threshold and exhausting the off-going clutch if the on-coming clutch is filled and the slip sign is correct; and locking the on-coming clutch if the slip is less than the slip threshold.

Abstract: A method of controlling a hydraulic CVT of a vehicle comprises: determining a speed of rotation of a driving shaft; determining a speed of rotation of a driven shaft; determining a ratio of the speed of rotation of the driving shaft versus the speed of rotation of the driven shaft; determining an engine torque; determining a base clamping force to be applied by the driving pulley onto the belt based on the ratio and the engine torque; determining a desired speed of rotation of the driving shaft; determining a corrective clamping force by comparing the speed of rotation of the driving shaft to the desired speed of rotation of the driving shaft; and controlling a hydraulic pressure applied to a movable sheave to apply a sum of the base and corrective clamping forces onto the belt. A vehicle having a CVT controlled by the method is also disclosed.

Abstract: A method for determining an operating state of elements of a transmission may include acquiring rotational speeds of both members constituting the elements, determining whether the rotational speeds of the members may be the same, and determining that the elements may be directly connected when the rotational speeds of the members may be the same, and that the elements may be disconnected or slip when the rotational speeds of the members may be different.

Abstract: In a method for detecting the status of the clutch in the drive train of a motor vehicle, the engine speed and the speed are ascertained and a transmission ratio is formed as the quotient of the engine speed and speed. Furthermore, a reference value is determined, which is set equal to the transmission ratio from a first time step. In a subsequent time step, the difference between the instantaneous transmission ratio and the reference value is formed, a disengaged clutch status being detected if the difference exceeds a threshold value.

Abstract: A linear solenoid is configured with an electromagnetic coil and a label resistor that are integrated with each other; the label resistor has a resistance value corresponding to a correction coefficient based on the difference between the actual characteristic of the supply current vs. adjusted hydraulic pressure output of the electromagnetic coil and a standard characteristic; and data for correcting a characteristic variation in the command current vs. output current characteristic of an electromagnetic coil is preliminarily stored in a control module by use of an adjustment tool. When the operation is started, the resistance value of the label resistor is read and an output current corresponding to a utilized linear solenoid is supplied, so that a target adjusted hydraulic pressure is obtained.

Abstract: A vehicle including an internal combustion engine and a stepped transmission including an input shaft and an output shaft, wherein the stepped transmission speed-changes power input to the input shaft while changing a shift speed and outputs the speed-changed power to the stepped transmission output shaft; a control unit that controls the engine and the stepped transmission in accordance with an output request from an operator. The vehicle also including input and output shaft rotation speed detecting units and an output limiting unit that limits the output of the engine by comparing the deviation of the input and output shaft rotation speed to a predetermined rotation speed relationship range. The vehicle also including an abnormality determining unit to determine that an abnormality has occurred in the stepped transmission when the rotation speed relationship exceeds the range of the predetermined rotation speed relationship for at least a first predetermined time period.

Abstract: A control device for an automatic transmission includes a speed change controller configured to generate a speed change instruction. A temperature calculator is configured to calculate a temperature of at least one frictional engagement element among frictional engagement elements. A rotation difference calculator is configured to calculate a rotation difference between an input and an output of the at least one frictional engagement element. A determining unit is configured to determine whether the frictional engagement element is engageable or non-engageable based on the temperature and the rotation difference of the frictional engagement element and a pattern of the speed change instruction. The delay unit is configured to delay engagement until the determining unit determines that the frictional engagement element is engageable, if the determining unit determines that the frictional engagement element is non-engageable when the speed change controller generates the speed change instruction.

Abstract: A system for transforming a variable output into an input having a desired speed value, including a transmission receiving the output having a first speed (Ve) and producing the input having a second speed (Vgen), first, second and third sensors producing data corresponding to the first speed (Ve), second speed (Vgen) and a power demand (Pdem) for the input, a ratio set point controller, a ratio controller and a speed controller. The ratio set point controller receives the data and calculates an available power (Pav), a stability level of the system (S,U1,U2), a desired value for the first speed (Ve), and a desired value and rate of change for the transmission ratio. The ratio controller interfaces the ratio set point controller and actuates the transmission to change the transmission ratio to the desired value following the desired rate of change. The speed controller changes the first speed (Ve) until the second speed (Vgen) corresponds to the desired speed value.

Abstract: A controller for a vehicle continuously variable transmission is disclosed. When a target gear ratio is set as the maximum gear ratio and a vehicle speed is decreased to less than a first reference vehicle speed, the controller suspends varying of the gear ratio by the transmission control and starts a gear ratio hold control that releases operational oil from a first oil pressure chamber and holds the gear ratio at the maximum gear ratio. Further, the controller ends the gear ratio hold control and delivers operational oil to the first oil pressure chamber when the vehicle speed increases to a second reference vehicle speed or greater, which is lower than the first reference vehicle speed, and restarts the varying of the gear ratio by the transmission control when the vehicle speed subsequently increases to the first reference speed or greater.

Abstract: A method for actuating a clutch in the drive train of a motor vehicle, including: generating a respective position setpoint for each predetermined target interval to actuate the clutch; in each predetermined target interval, actuating the clutch in a plurality of predetermined controller sampling intervals; discretizing a respective position setpoint change into a plurality of intermediate position setpoints; determining a number of intermediate position setpoints in the plurality of intermediate position setpoint depending on the ratio of the target interval to the controller sampling interval; and specifying the respective position setpoint changes in steps to actuate the clutch.

Abstract: A vehicle control device for controlling a vehicle drive apparatus, the vehicle control device configured with a release control mechanism that provides feedback controlling supplied oil pressure to a release side element, and an engagement control mechanism that increases supplied oil pressure to an engagement side element as an engagement element on a side to be engaged in a state that the differential rotation speed is substantially constant. The control device is further configured with a phase determining mechanism that determines if the torque phase has started when a condition that a phenomenon accompanying a change of the differential rotation speed due to increase of the supplied oil pressure to the engagement side element is detected is met.

Abstract: A method and a device for controlling the slip of a tractor vehicle or the like, in which the drive wheel slip is determined and, if the actual slip is different from a specified nominal slip, the gear ratio of a controllable transmission in the drivetrain is adjusted in the direction of slip optimization. The transmission is a geared-neutral transmission whose output speed, at full drive power, can be adjusted to an extremely small value close to zero.

Abstract: In an automatic transmission controller, a gear shift control unit has a target rotational angle position calculator for calculating a target rotational angle position of a gear shift motor, an actual rotational angle position calculator for calculating the actual rotational angle position of the gear shift motor, and an F/B gain setting unit. When a gear shift instruction from a gear shift controller is a gear shift pattern for driving at least a select motor, the F/B gain is set to be larger that of the gear shift pattern in which the select motor is not driven, and also a motor driving mode and a motor braking mode are switched to each other in accordance with the difference between the target rotational angle position and the actual rotational angle position.

Abstract: One disclosed embodiment relates to a propulsion system for a machine. The propulsion system may include a prime mover operatively connected through a continuously variable transmission to a propulsion device. The propulsion system may also include propulsion-system controls that control an operating parameter of the continuously variable transmission, which may include adjusting the operating parameter based on operator input. Controlling the operating parameter may also include determining an adjustment limit for the operating parameter based on one or more operating conditions and applying the adjustment limit to the operating parameter to modify at least one of acceleration and jerk of the machine based on the one or more operating conditions.

Abstract: In a series hybrid vehicle, a system for determining a shift schedule for shifting a multi-gear transmission connected to a drive means is disclosed. A vehicle operator selects among a plurality of shift styles respectively representing a plurality of shift schedules variously optimized for performance or fuel economy. A performance-based shift schedule favors providing maximum power to the road by starting at the first (lowest) gear when accelerating from a stop and utilizing all available gears of the transmission. An economy based shift schedule favors energy efficiency by skipping the first gear and optionally one or more higher-numbered gears in order to bias operation of the drive means toward lower speeds and higher torque output while reducing shift frequency.

Abstract: A control method and system for a vehicle transmission that incorporates gradient road resistance in selecting an appropriate gear ratio for an automatic manual transmission or an automatic transmission are disclosed. The traction resistance of a vehicle is calculated in order to determine the traction force required for maintaining, increasing, or decreasing vehicle speed in response to operator input. Traction resistance may be a function of rolling resistance, air resistance, and the component of the gravitational force acting parallel to the road surface. The change in traction resistance is also determined. The calculated traction resistance and change in traction resistance may advantageously be used to calculate an offset to a shift point motor speed in order to delay or advance a transmission upshift when climbing a grade.

Abstract: The described system and method allow a controller to calibrate a transmission variator of a continuously variable transmission for torque control by obtaining static and dynamic qualities and parameters of the variator through an automated calibration procedure. The system and method employ a pair of transmission mode configurations and operational configurations in combination to obtain system-specific information. In this way, the system is able to calibrate out the system variations to provide effective feed forward torque control of the continuously variable transmission. In an embodiment, a first calibration operation is performed while the transmission is neutralized and a second calibration operation is performed while the transmission is engaged in a mode providing a fixed variator output speed.

Abstract: An engine rotational speed control apparatus is provide to prevent a degradation of fuel efficiency caused by an unnecessary increase of the rotational speed of an engine when a depression amount of an accelerator pedal is briefly increased and then immediately decreased. In particular, when the vehicle is accelerated, an optimum fuel efficiency operating point along an optimum fuel efficiency curve is not moved immediately to another optimum fuel efficiency operating point corresponding to a new target drive force. Instead, the target drive force is reached by increasing the engine load while increasing the engine rotational speed as little as possible, and thus using an operating point that does not lie on the optimum fuel efficiency curve.

Abstract: An ECU executes a program that outputs a shift command when a determination has been made to perform a power-on downshift (i.e., YES in S100); controls the hydraulic pressure supplied to a friction engagement element to perform the power-on downshift; allows the correction of the hydraulic pressure supplied to the friction engagement element during the power-on downshift when the difference between a target input torque and an estimated input torque is equal to or less than a threshold value ?TT (1) (i.e., YES in S130); and correcting the hydraulic pressure supplied to the friction engagement element during the power-on downshift.

Abstract: A control device for an automatic transmission is disclosed wherein a shift point depending on a variation in vehicle acceleration is modified on a real time basis in accordance with not only a corrected result on a shift point depending on piece-to-piece variations of automatic transmissions, but also actual acceleration for shortening a time required for learning with high precision with no need to be matched. Shift point real-time modifying means is provided for modifying the altered shift point based on a value of a ratio between a value of actual engine-rotation acceleration at an upshift-determining timing during a power-on running and a value of reference engine-rotation acceleration obtained by substituting a value of actual engine-rotation acceleration to a value for a reference running state having no impact on acceleration of a vehicle, and a target maximum engine rotation speed.

Abstract: A control device is provided for a vehicle drive apparatus, which includes a differential mechanism and an electric motor provided in differential mechanism, which can be miniaturized in structure with improved fuel economy or enabling the suppression of occurrence in switching shocks. With a provision of a switching clutch C0 or a switching brake B0, a shifting mechanism 10 is placed in either a continuously variable shifting state or a step variable shifting state. This enables the vehicle drive apparatus to have combined advantages in a fuel economy improving effect with a transmission, enabled to electrically change a gear ratio, and a high transmitting efficiency with a gear type power transmitting device enabled to mechanically transmit drive power. During a shifting of an automatic shifting portion 20, engaging control variable control means 84 alters a method of learning an engaging pressure.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: An improved downshift control for an automatic transmission optimized for sequential shifting achieves a non-sequential fifth gear to third gear downshift by reducing the main pressure of the transmission hydraulic control system, allowing a offgoing clutch to slip, disengaging the offgoing clutch, using torque reduction to control engine speed, engaging the oncoming clutch, increasing the main pressure of the transmission hydraulic control system and using torque reduction to synchronize the transmission input speed with the third gear transmission output speed.

Abstract: An ECU executes a program including the steps of: setting a first throttle opening degree (S100), setting a low gear torque LTE based on an engine torque map for low gear having the first throttle opening degree and an engine speed (rpm) as parameters (S200), setting a high gear torque HTE based on an engine torque map for high gear having the first throttle opening degree and the engine speed as parameters (S300), setting a target engine torque TTE by combining the low gear torque LTE and the high gear torque HTE by using a correction ratio KGR determined by a gear step (S400), and controlling the engine to produce a required torque set by using the target engine torque TTE (S700). In this way a torque can be obtained in accordance with the engine speed.

Abstract: An automatic transmission includes gears, torque-transmitting mechanisms, interconnecting members, an input member and an output member. A method of controlling the automatic transmission includes data acquisition from the output shaft torque sensor, commanding a hydraulic fluid pressure pulse time and a pressure pulse value to engage a first torque-transmitting mechanism, calculating a rate-of-change of a first data output from the output shaft torque sensor, calculating a rate-of-change of a second data output from the output shaft torque sensor, comparing the results of the rate-of-change calculations and adjusting the hydraulic fluid pressure pulse time and a pressure pulse value if the rate of change of the second data output is not equal to the rate-of-change of the first data output.

Abstract: A method of controlling a hydraulic CVT of a vehicle comprises: determining a speed of rotation of a driving shaft; determining a speed of rotation of a driven shaft; determining a ratio of the speed of rotation of the driving shaft versus the speed of rotation of the driven shaft; determining an engine torque; determining a base clamping force to be applied by the driving pulley onto the belt based on the ratio and the engine torque; determining a desired speed of rotation of the driving shaft; determining a corrective clamping force by comparing the speed of rotation of the driving shaft to the desired speed of rotation of the driving shaft; and controlling a hydraulic pressure applied to a movable sheave to apply a sum of the base and corrective clamping forces onto the belt. A vehicle having a CVT controlled by the method is also disclosed.

Abstract: A method of controlling a vehicle includes signaling a transmission to shift into a first gear ratio and sensing a current gear ratio of the transmission after signaling the transmission to shift into the first gear ratio. The method further includes implementing a diagnostic transmission shift control strategy to override a normal transmission shift control strategy when the current sensed gear ratio is not equal to the requested first gear ratio to verify proper functionality of a mode control valve that is responsible for shifting the transmission into the first gear ratio.

Abstract: A method for shifting gears of an automatic transmission of a vehicle, by way of primarily form-locking shifting elements, while driving with or without utilization of a clutch depending on a decision made by a decision device which, in the presence of certain basic conditions, causes disengagement of a starting gear without disengaging the clutch, and subsequently reads in data about the size and the progression of a quantity correlating closely with the rotational speed of an output shaft of the automatic transmission and, with inclusion of this data, determines the shifting mode for engagement of the target gear.

Abstract: The present invention provides a mode change control method of a hybrid vehicle, which can improve driving performance and power performance and provide a more stable vehicle behavior control during a mode change from an EV mode to a HEV mode. For this purpose, a transmission input speed is compared with an engine idle speed. If the transmission input speed is lower than the engine idle speed, the pressure of a clutch is open-loop controlled so that an optimal engine torque of operation point determination circuit can be transferred to the clutch. On the other hand, if the transmission input speed is equal to or higher than the engine idle speed, the clutch pressure is feedback-controlled so that a delta RPM follows a target delta RPM profile.

Abstract: During control of a shift of a first friction engagement element from an engaged state into a disengaged state and a shift of a second friction engagement element from a disengaged state into an engaged state for a gear shift to a first target gear from a second target gear, a desired torque capacity of the first friction engagement element is set based on an actual transmission gear ratio by interpolation from values of the desired torque capacity corresponding to at least first and second reference transmission gear ratios, wherein the first reference transmission gear ratio is a transmission gear ratio at start of an inertia phase of the shift control. When the first reference transmission gear ratio is between the actual transmission gear ratio and the second reference transmission gear ratio, the desired torque capacity is set to the value corresponding to the first reference transmission gear ratio.

Abstract: A method and system for configuring a hydromechanical transmission having a hydraulic pump and a hydraulic motor driven by the hydraulic pump and a pressure-driven actuator employs a particular torque-pressure curve configuration to maximize torque resolution with respect to actuator pressure changes while ensuring that the curve is substantially monotonic in each dimension and at any available motor speed within a predetermined motor speed limit and any available actuator pressure within predetermined actuator pressure limits. The resultant four-dimensional association between actuator pressure, motor speed, primary power source speed and motor torque allows selection of an actuator pressure to provide a desired torque.

Abstract: A transmission has an input member and an output member, first and second intermediate shafts having substantially identical gear sets with gears concentric with and selectively connectable for rotation with the first and second intermediate shafts, respectively. Output gears are concentric with and rotatable with the output member and mesh with the substantially identical gear sets. First and second torque-transmitting devices are operable for transmitting torque from the input member to the first and second intermediate shafts, respectively. Torque-transmitting mechanisms are mounted concentric with, rotatable about and selectively engagable with the gears mounted on the intermediate shafts. A controller is operatively connected to the torque-transmitting mechanisms and to at least one of the torque-transmitting devices.

Abstract: A method of operating a transmission device comprising friction-locking and form-locking shift elements for obtaining different gear ratios. A shift request for engaging a shift element undergoes a time delay dependent upon an operating state prior to a time of engagement of the shift element. A rotational speed differential between halves of the shift element lies within a rotational speed differential window required for the engagement procedure is assigned to the time of engagement. A gradient of the transmission input speed is ascertained at the time of the shift request, and the actual gradient is subsequently monitored and compared with the gradient that existed at the time of the shift request. If an absolute deviation greater than a threshold value is ascertained, the time delay is changed or an actuation of another shift element to be disengaged is varied such that the deviation is reduced below the threshold value.