Abstract: A system for controlling the engagement and disengagement of one or more clutches that are adapted to operatively connect an engine and an automatic transmission includes a control device for determining if a negative torque condition exists and for providing an output or signal to decrease the rotational speed of the engine in response to the determination of the existence of the negative torque condition.

Abstract: Methods and systems for managing acceleration of a motor vehicle having an automatic transmission by controlling transmission turbine acceleration are provided. A desired transmission turbine acceleration is determined based on vehicle speed, turbine speed, and other information obtained from the vehicle transmission. One or more torque limits are determined as a function of the turbine acceleration. The torque limits are applied to manage acceleration of the vehicle.

Abstract: An apparatus and a method for controlling an automatic transmission that executes the learning of a shift point and provides an optimal upshift even when a vehicle is driven under conditions where resistance to driving varies greatly, such as when going up or down a hill or when towing. A reference engine acceleration is calculated and used to estimate a maximum engine rotational speed based on the relationship between the reference engine rotational acceleration and the engine rotational acceleration speed at an shift point. The shift point is corrected based on the deviation between the estimated engine rotational speed and a target maximum engine rotational speed at the shift point.

Abstract: Since there are provided an inertia phase final period decision unit which decides whether or not the final period of the inertia phase of a speed change is currently occurring, a return control unit which, taking an affirmative result of this decision as a starting condition, performs return control in order to return from the torque down control by gradually decreasing the amount of decrease of output torque, a speed change progression decision unit which, during this return control from the torque down control, decides whether or not the speed change is progressing, and a resumption control unit which resumes the torque down control if the result of this decision is negative, accordingly, during the return control from the torque down control, by resuming the torque down control when there is no progression with the speed change.

Abstract: In performing a down-shift based on a driver's intention of deceleration, an engine output increasing control is started at a time when a transfer torque capacity of the releasing clutch becomes small or zero and the actual oil pressure decreases to an initial oil pressure, not causing an acceleration feeling even upon the engine output increase. For estimating a time when which the real pressure of the releasing clutch decreases to a level of not higher than the initial pressure, the response of the real pressure relative to an oil pressure command value for the releasing clutch is approximated using a transfer characteristic of “first order lag+time delay.” An estimated real oil pressure obtained based on the transfer characteristic is compared with the initial pressure. It is determined a start timing of the engine output increasing control has been reached upon decrease of the estimated pressure to the initial pressure.

Abstract: A driver operates a shift pedal to perform shift change of a transmission via a shift mechanism provided in a vehicle. An operation of the shift pedal is detected by a load sensor. When a sliding gear and a fixed gear of the transmission continue to be separated from each other for a predetermined period of time or longer after a shifting operation by the driver is detected by a load sensor, the rotational speed of the engine is maintained within a target range by an ECU.

Abstract: A powered scale model vehicle having a transmission with a forward gear and a reverse gear. The transmission is shiftable between the forward gear and the reverse gear. The vehicle has a radio control receiver, a sensor and a microcontroller. The receiver is adapted to output a throttle signal and a shift signal to the microcontroller. The sensor is adapted to obtain a vehicle speed measurement. The microcontroller is electrically coupled to the receiver and the sensor. The microcontroller may be adapted to control a timing and execution of a forward/reverse shift on the transmission based on at least the vehicle speed measurement, the throttle signal, and the shift signal, for example.

Abstract: A method of controlling driveshaft speed includes generating an overspeed protection action signal if an engine speed limit and a requested transmission gear ratio correspond to a driveshaft overspeed condition. An operating method for a machine includes disengaging a relatively higher transmission gear, and inhibiting re-engagement of the higher transmission gear responsive to an overspeed protection action signal. An electronic controller for the machine is configured to generate an overspeed protection action signal responsive to an engine speed limit and requested transmission gear ratio.

Abstract: A system is provided for controlling the speed of a vehicle having a powertrain including a power plant operably coupled to a transmission. The system includes a control unit configured to receive a signal indicative of vehicle speed, receive a signal indicative of power plant output speed, and determine a desired power plant output speed based on the signal indicative of vehicle speed and the signal indicative of power plant output speed. The control unit is further configured to send a signal to the power plant such that the power plant operates at the desired power plant output speed, and maintain a desired vehicle speed in a manner substantially independent of a magnitude of load on the powertrain.

Abstract: The invention relates to a shift control apparatus for an automatic transmission that executes a torque reduction control when the transmission downshifts in response to a downshift determination made during an upshift. The shift control apparatus includes a multiple shift execution unit that starts the downshift in response to the downshift determination, and a torque reduction control execution unit that determines whether the rotational speed of the input member is at least a control start-up rotational speed, after the downshift operation starts, and executes a torque reduction control of the power source when the rotational speed of the input member is increased to at least the control start-up rotational speed. This allows the rotational speed of the input shaft to be quickly changed to the appropriate synchronous rotational speed. Thus, the desired driving force is provided upon completion of the downshift without overspeeding the engine.

Abstract: A powertrain system includes a transmission operative to transfer power between an input member and first and second torque machines and an output member. The first and second torque machines are connected to an energy storage device and the transmission is operative in a continuously variable operating range state.

Abstract: An engine is mechanically coupled to a transmission device, the transmission device operative to transfer mechanical power between the engine and a second power generating device and an output member. A method for controlling the engine includes monitoring an operator demand for power, selecting a preferred engine state, determining a preferred engine torque input to the transmission device when operating in the preferred engine state based upon the operator demand for power, determining constraints on the engine torque input to the transmission device based upon a capacity of the transmission device to react the engine torque input, and commanding operation of the engine to the preferred engine state and commanding the engine torque input to the transmission device based upon the preferred engine torque input and the constraints on the engine torque input.

Abstract: A method of inhibiting an overspeed condition in a vehicle powertrain includes monitoring at least one of an engine speed and a transmission input shaft speed of a torque converter that transfers drive torque between an engine and a transmission and determining an operating condition of the vehicle powertrain. The method further includes determining a first threshold speed based on the operating condition and reducing an engine torque request when the at least one of the engine speed and the transmission input shaft speed exceeds the first threshold speed.

Abstract: An engine starting system for a power train including an engine and an automatic transmission includes an engine stop/restart controller. The automatic transmission having special mode includes first and second planetary gear sets having respective sun gears, a turbine shaft, an output gear, a forward clutch and a 2-4 brake. The forward clutch sets the automatic transmission in a drive condition when engaged and in a neutral condition when disengaged. If the special mode is selected under conditions where the output gear is locked, the sun gear of the first planetary gear set is locked. During execution of automatic engine stop control operation, the engine stop/restart controller causes the automatic transmission to initiate a transfer to the special mode before fuel supply is interrupted and causes the forward clutch to completely engage at a specific point in time after the automatic transmission has completed the transfer to the special mode.

Abstract: A method for shifting an automated transmission situated in a drive train of a motor vehicle between an engine and a drive axle and having at least one multi-speed main transmission and a two-speed range change group rear-mounted thereon. The main transmission has at least one counter shaft with a transmission brake. A clutch engages the prime mover and the main transmission and the range change group is shifted via unsynchronized dog clutches which are combined in pairs in a common shift set and have two shift positions and one neutral position such that, during a range change gear shift both in the main transmission and the range change group a change between two ratio stages occurs. A range change up-shift includes synchronizing the input shaft and the target gear utilizing the transmission brake and passively synchronizing the dog shifted transmission parts by the edge beveling of the concerned dog clutches.

Abstract: An automatic or automated transmission of a motor vehicle and a method for control of the transmission in which in an emergency operation of the transmission a maximum admissible engine torque and a maximum admissible engine rotational speed of a prime mover of the motor vehicle connected or connectable with the transmission and a maximum admissible transmission input torque and a maximum admissible transmission rotational speed are limited compared to a normal operation. After a change from emergency operation back to normal operation of the transmission, a starting performance of the motor vehicle is time limited, especially limited in time and gradually limited depending on events.

Abstract: A method for selecting a shift schedule for a transmission in a motor vehicle is provided. The method includes the steps of determining whether a signal-to-noise ratio exceeds a threshold and calculating a tractive effort of the motor vehicle. A vehicle mass and a road grade is then estimated from the tractive effort using a recursive least squares estimator with multiple forgetting when the signal-to-noise ratio exceeds the threshold. A vehicle mass is selected and the road grade estimated from the vehicle mass and tractive effort when the signal-to-noise ratio does not exceed the threshold. A shift schedule is then selected based on the vehicle mass and the estimated road grade.

Abstract: A method for regulating or controlling the transmission ratio of an automatic power-branched transmission. Power is transmitted through a shaft driven by an engine, a variable speed drive, a gear transmission, a driven shaft, and at least two control clutches. The variable speed drive and the gear transmission are connected to each other in such a way that the regulating range of the variable speed drive is traversed in one direction within a first range of transmission ratios, and is traversed in the opposite direction within a second range of transmission ratios during traversing of the entire range of transmission ratios. The shifting strategies result in reduced wear of the endless belt device and allow for comfortable changing between the transmission ratio ranges.

Abstract: This invention provides a method for controlling a gear ratio in an automatic transmission of a vehicle. The method includes detecting a desired engine braking condition associated with the vehicle. Once the engine braking condition is determined, a decay factor is determined for reducing the gear ratio of the transmission. The decay factor maintains the gear ratio for a delayed period of time before gradually reducing the gear ratio over time. After determining the decay factor, the gear ratio of the transmission is controlled in accordance with the decay factor.

Abstract: A system for use with a vehicle such as a tractor having an output device such as a mower deck or snow thrower comprising a sensor positioned to detect the rotational direction of a shaft such as an output axle. The operational status of the output device can be changed depending on the rotational direction of the shaft.

Abstract: An engine controller controls an engine, which drives a generator, an auxiliary device, and a vehicle. The generator generates electricity, and supplying the electricity to a battery and a plurality of current consumers. A generator controller controls the generator. An auxiliary device controller controls the auxiliary device. An electric power generation calculation unit calculates one of a requested power generation of the generator and a present power generation of the generator. An engine speed changing unit evaluates tendency of power generation on the basis of the one of the requested power generation and the present power generation. The engine speed changing unit requests increase or decreases in the engine speed when the engine speed changing unit determines the power generation to be inclined toward shortage or excess.

Abstract: A method of automatically matching engine speed to vehicle speed while a manual transmission is shifted. The currently selected speed ratio is determined from the ratio of engine speed and vehicle speed. The operator initiates a shift by disengaging the clutch. The operator's throttle inputs before and after clutch disengagement imply whether he wishes an upshift of one speed ratio or a downshift of one or two speed ratios. While the clutch is disengaged, the engine computer acts to bring the engine to the speed needed for smooth reengagement of the clutch. Engine speed control returns to the operator upon clutch engagement.

Abstract: A vehicle engine control apparatus provides rotational speed synchronization control during a shift operation. A shift operation detecting component detects a shift position resulting from a manual shift operation of a manual transmission connected to an engine. A vehicle speed detecting component detects a vehicle speed. The computing component computes an input side transmission rotational speed value based on the vehicle speed and a gear ratio. A driving intent determining component determines a driver's driving intention.

Abstract: A control apparatus for a vehicular power transmitting system including (a) an electrically controlled differential portion which has a differential mechanism and a first electric motor connected to a rotary element of the differential mechanism and which is operable to control a differential state between rotating speeds of its input and output shafts by controlling an operating state of the first electric motor, and (b) a step-variable transmission portion which constitutes a part of a power transmitting path between the electrically controlled differential portion and a drive wheel of a vehicle, the control apparatus including a coasting-shift-down control portion configured to implement a coasting shift-down action of the step-variable transmission portion during a coasting run of the vehicle, only when a parameter correlating with a shaft torque of the step-variable transmission portion during the coasting run is held within a predetermined range.

Abstract: A control for a vehicle including a controller for a propulsion motor unit, which generates a signal representative of the depression of an accelerator pedal operated by the vehicle driver and detects a degradation of the signal. On detection of such a degradation the speed of the vehicle is regulated if above a threshold value and the operating speed of the engine is regulated if the vehicle speed is below the threshold value.

Abstract: An automatic transmission control system includes a shift map that includes predetermined ranges of vehicle speeds at which vehicle engine speeds require gear shifts for the automatic transmission based on requests for torque. The predetermined ranges include upper bounds that correspond to gear upshifts and lower bounds that correspond to gear down shifts. A shift map control module varies at least one of the predetermined ranges of vehicle speeds based on at least one vehicle condition that affects movement of the vehicle.

Abstract: There is provided a method and apparatus to determine operating conditions for a powertrain comprising an internal combustion engine and first and second electrical machines and an electro-mechanical transmission selectively operative to transmit torque therebetween. The method comprises determining a torque output and an operating cost for operating the first and second electrical machines of the hybrid transmission effective to meet an operator torque request when the engine is operating in an engine-off operating state. Determining the torque output for operating the first and second electrical machines comprises executing a predetermined system equation effective to determine motor torque outputs from each of the first and second electrical machines based upon the selected parametric value for the input torque and the operator torque request.

Abstract: Vehicle (A) with an internal combustion engine (1), an automated transmission (2) coupled to the engine, and electronic control elements (3) which control the supply of fuel to the engine combustion chambers and recirculation of exhaust from the engine exhaust side (7) to its intake side (6). The control elements are disposed to compute, while the vehicle is moving, future driving resistance and the time until a future shifting between gears and to control valve elements (9) which regulate exhaust return flow during this time to optimize fuel consumption and emissions, when the gearshifting takes place.

Abstract: A control system for an internal combustion engine having a plurality of cylinders and a switching mechanism for switching between an all-cylinder operation in which all of the plurality of cylinders are operated and a partial-cylinder operation in which at least one of the plurality of cylinders is halted. A condition for performing the partial-cylinder operation is determined, based on the detected operating parameters of the vehicle driven by the engine. A result of the determination is modified so that the partial-cylinder operation may be continued, when the detected operating parameters satisfy a predetermined continuation condition within a predetermined time period from the time a vehicle operating state where the condition for performing the partial-cylinder operation is satisfied, has changed to another vehicle operating state where the condition for performing the partial-cylinder operation is not satisfied.

Abstract: Method and arrangement for controlling actual torque in a driveline of a land-based motor vehicle. Taking a direct, non-predictive measure of actual torque induced in the driveline of the motor vehicle and ascertaining a magnitude thereof. Ascertaining a magnitude of a torque demand being requested to be instituted in the driveline. Comparing the ascertained magnitude of the direct, non-predictive measure of actual torque taken is compared with a driveline-configuration dependent maximum torque threshold; in this way, an over-threshold torque condition is ascertained in the driveline based thereupon if such a condition exists. In multi-geared transmissions, the variability can be accounted for through the engagement of different ratio gears. In the event that such an over-threshold torque condition is detected, at least one of several possible over-threshold torque compensating effects will be applied to reduce or diminish the excessive portion of the torque.

Abstract: Method and arrangement for controlling or regulating total auxiliary brake torque in a motor vehicle. The device includes at least one first auxiliary brake (4) of a first type and at least one second auxiliary brake (4, 6) of a second type that is different from the first type. The second auxiliary brake (4, 6) can take the form of a retarder (4, 6). A control system (10, 17) is provided for controlling or regulating the auxiliary brake. Information is stored in the control system regarding characteristics of the respective auxiliary brake (4, 6) and at least one predefined limit value for maximally permitted auxiliary brake torque. The control system (10, 17) is designed such that, if the limit value is exceeded or if a request is made for the brake force from the auxiliary brakes (4, 6) to be moderated, then this is done by turning down or moderating, in the first place, the brake torque of the retarder (6).

Abstract: A torque request generation system for use with a coordinated torque control system of a vehicle includes an input receiving a vehicle speed and an axle torque command. A datastore records a three-dimensional torque surface defined in terms of a coordinate system having a first axis related to the axle torque command, a second axis related to the vehicle speed, and a third axis related to an axle torque request. A torque request generation module accesses the datastore and generates a torque request based on a correlation between the axle torque command and the vehicle speed respective of the three-dimensional torque surface.

Abstract: A reverse system for an all-terrain vehicle (ATV) having an engine and an engine drive shaft, a reverse activator, an engine speed limiter, and an override switch. The reverse activator is coupled to the drive shaft. The reverse activator activates operation of the ATV in a reverse direction. The engine speed limiter limits engine speed to below a predetermined level while the reverse activation switch is engaged. The override switch allows engine speeds above the predetermined level only when the transmission is in four-wheel-drive. The method of carrying out the invention is also disclosed.

Abstract: A method of producing lower emissions in the operation of a vehicle includes an internal combustion engine which gives off exhaust gases to an exhaust system comprising a catalytic converter, injectors which are designed to inject hydrocarbon into at least one of the exhaust system and the engine combustion chamber, and a transmission that can be driven by the engine. The method includes a step in which a gear in the vehicle transmission is selected as a function at least of information that catalytic conversion is required and information on the temperature in the exhaust system, so that the gear selected regulates the temperature in the exhaust system. The catalytic converter is preferably of the LNC (Lean NO, Catalyst) type.

Abstract: A continuously variable planetary gear set is described having a generally tubular idler, a plurality of balls distributed radially about the idler, each ball having a tiltable axis about which it rotates, a rotatable input disc positioned adjacent to the balls and in contact with each of the balls, a rotatable output disc positioned adjacent to the balls opposite the input disc and in contact with each of the balls such that each of the balls makes three-point contact with the input disc, the output disc and the idler, and a rotatable cage adapted to maintain the axial and radial position of each of the balls, wherein the axes of the balls are oriented by the axial position of the idler.

Abstract: An acceleration shock reduction control system for a vehicle which can reduce a shock at a transition to an accelerating state without deteriorating an acceleration response. An acceleration shock reduction control system for vehicle includes a control unit which determines a transition from a decelerating state to an accelerating state, and which thus controls the ignition of an internal combustion engine to adjust the output of the engine. In the acceleration shock reduction control system, upon detecting the transition from the decelerating state to the accelerating state, the control unit gives an instruction for an ignition cut which is executed over a predetermined time period Tr after a predetermined waiting time period Tw elapses.

Abstract: Hybrid controller 52 for a vehicular drive system is operable during a shifting control of step-variable transmission portion 20 for a stepping change of its speed ratio, for changing a speed ratio of continuously-variable transmission portion 11, such that total speed ratio ?T of transmission mechanism 10 defined by the speed ratio of the continuously-variable transmission portion 11 and the speed ratio of the step-variable transmission portion 20 is continuously changed, irrespective of the stepping change of the speed ratio of the step-variable transmission portion 20, so that an amount of stepping change of engine speed NE before and after a shifting action of the step-variable transmission portion 20 is reduced, and a shifting shock of the step-variable transmission portion 20 is reduced. The hybrid controller 52 permits the transmission mechanism 10 to function as a continuously variable transmission, thereby improving fuel economy of the vehicular drive system.

Abstract: In performing a down-shift based on a driver's intention of deceleration, an engine output increasing control is started at a time when a transfer torque capacity of the releasing clutch becomes small or zero and the actual oil pressure decreases to an initial oil pressure, not causing an acceleration feeling even upon the engine output increase. For estimating a time when which the real pressure of the releasing clutch decreases to a level of not higher than the initial pressure, the response of the real pressure relative to an oil pressure command value for the releasing clutch is approximated using a transfer characteristic of “first order lag+time delay.” An estimated real oil pressure obtained based on the transfer characteristic is compared with the initial pressure. It is determined a start timing of the engine output increasing control has been reached upon decrease of the estimated pressure to the initial pressure.

Abstract: A process for controlling an automated motor vehicle drive train which has an engine and a transmission, with the step of at least once detecting at least one wear parameter of the transmission during its running performance, the wear parameter representing the wear or the fatigue of at least one component of the transmission. A load limit parameter, which represents the maximum load on the transmission due to the engine, is set as a function of the detected wear parameter.

Abstract: A method of performing a directional shifting event in a hydrostatic drive work machine, and a hydrostatic drive work machine is provided. The method includes the step of adjusting a pump displacement of a variable displacement pump coupled with an engine and a hydraulic motor of the work machine, at a rate based at least in part on one or both of a predetermined acceleration limit and a predetermined jerk limit of the work machine. The work machine includes an electronic control module having a computer readable medium with a directional shifting control algorithm recorded thereon. The control algorithm is operable to adjust a pump displacement in a hydrostatic drive of the work machine at a rate based at least in part on one or both of the predetermined acceleration limit or jerk limit of the work machine.

Abstract: A method and a device for operating a drive unit provide a switch between half-engine operation and full-engine operation. A switch takes place between two operating states of a first component of the drive unit as a function of a first performance quantity of the drive unit. A switch takes place between two operating states of a second component of the drive unit as a function of a second performance quantity of the drive unit. A check is performed whether switching between two operating states of the second component results in a shift of the first performance quantity over a switching threshold for switching between two operating states of the first component, and if so, the switch between the two operating states of second component is delayed until a switch between the two operating states of first component has occurred.

Abstract: In an engine control system mounted on a machine such as a walk-behind truck through a CVT and having an actuator whose operation is controlled such that a detected engine speed becomes equal to a desired engine speed, the output of the engine is estimated based on the detected engine speed and a detected throttle opening, the desired engine speed is changed when the estimated engine output is greater or smaller than output threshold values, and a speed reduction ratio of the CVT is also changed based on the detected engine speed such that a detected speed of the CVT output shaft speed becomes equal to a desired output shaft speed, thereby enabling to reduce the fuel consumption and noise of the engine.

Abstract: A transmission control device for a vehicle for smoothly performing a transmission manipulation without a clutch manipulation. The device includes a control unit which determines a shift operation starting time based on a detection signal of a shift operation detector, and controls an intake air amount to an engine corresponding to a gear shift position detected by a gear shift position detection means thereby changing an output of the engine. The control unit obtains a target initial throttle opening corresponding to the gear shift position from a target initial throttle opening table, obtains data on throttle opening, time and an attenuation ratio corresponding to the gear shift position from a throttle opening, time and attenuation ratio table, and determines the opening time and the target throttle opening. Next, the control unit determines an injection amount and executes control to increase the intake air amount and the injection quantity.

Abstract: When a determination for a second shift is made during a first shift process, if the turbine speed is the variety of the synchronous rotational speed for the speed to which the automatic transmission is to be shifted in the second shift and the hydraulic pressure command value for the first brake, which is engaged in the second shift, is equal to or larger than a predetermined value, the multiple shift portion immediately switches the shift control from the first shift control to the second shift control so that the hydraulic pressure command value for the first brake, which is engaged in the second shift, increase at a specific rate and the hydraulic pressure command value for the third brake, which is released in the second shift, decreases at a specific rate.

Abstract: The present invention provides a universal power control module for automatic transmissions. The power control module includes a processor and at least two sensor inputs that convey engine and vehicle data to the processor. This data may include vehicle speed, engine temperature, throttle position, engine RPM, and other operational parameters. Both the type and number of data input to the processor may be changed to accommodate different engine and transmission combinations. At least two outputs convey commands from the processor to the transmission. Program circuitry defines the gear shift pattern of the transmission according to the engine and vehicle sensor data. This program circuitry can be programmed to define an optimal gear shift pattern for any combination of engine and transmission, independent of make and model.

Abstract: A control device for an automatic transmission includes: a control portion that executes a neutral control to release the friction engagement element if a progressing position of the automatic transmission is selected, and a state of the vehicle satisfies a certain condition; a detection portion that detects degree of deceleration of the vehicle before the neutral control is executed; and a releasing portion for releasing the friction engagement element to be in a released or semi-released state in accordance with a shift of the automatic transmission if the degree of deceleration is greater than a predetermined degree.

Abstract: A drive arrangement for an agricultural machine with an internal combustion engine used to drive removable agricultural implements. The engine is connected to a control unit and to a power take-off (PTO), which drives the removable agricultural implements, by means of a power take-off transmission with selectable transmission steps. The engine is further coupled to a sensor that captures the RPM of the PTO outlet, to a first operator input device that influences the RPM of the combustion engine and to a second operator input device that inputs a maximum RPM of the PTO output. The control unit controls the RPM of the combustion engine to the input value of the first operator input device while limiting the RPM of the engine based on the RPM at the PTO outlet, which cannot exceed the input value of the second operator input device.

Abstract: A torque converter bump control system is provided. The system includes: a gain module that computes a torque converter gain based on a speed ratio; an increased gain module that computes an increased torque converter gain based on turbine speed; a blended gain module that computes a blended torque converter gain based on the torque converter gain, the increased torque converter gain, and a blend ratio; and a final gain module that selectively sets a final torque converter gain based on the speed ratio and commanded engine torque to at least one of the torque converter gain, the increased torque converter gain, and the blended torque converter gain and wherein engine torque is controlled based on the final torque converter gain.

Abstract: In a shift-shock reducing apparatus of a power train employing an engine and an automatic transmission, an engine controller executes engine-torque correction for canceling an inertia torque generated owing to a change in transmission input speed during a shift, for shift-shock reduction. A transmission controller includes a shift-speed correction circuit for compensating for a shift speed of the automatic transmission depending on engine load, so as to effectively suppress the generated inertia torque, thereby aimfully reducing or suppressing shift shocks.

Abstract: An ECT_ECU executes a program including the step of identifying the drive mode, the step of determining whether the engine is in an idling state or not, the step of detecting the speed of an automatic transmission when not in an idling state, the step of detecting an accelerator press-down rate of change, the step of detecting vehicle speed, the step of calculating a target acceleration rate of change of the vehicle based on the drive mode, speed of the automatic transmission, accelerator press-down rate of change, and vehicle speed, and the step of calculating the target acceleration by integrating the calculated target acceleration rate of change with respect to time.