Abstract: In one example, A method for controlling a powertrain of a vehicle with wheels, the vehicle having a pedal actuated by a driver, is described. The method may include generating powertrain torque transmitted to the wheels in a first relation to actuation of the pedal by the driver during a first condition where said transmitted torque causes said wheels to slip relative to a surface; overriding said driver actuated powertrain torque to control said slip; and during a second condition after said first condition where said vehicle is moving less than a threshold, generating powertrain torque transmitted to the wheels in a second relation to actuation of the pedal by the driver, where for a given pedal position, less powertrain torque is transmitted with said second relation compared to said first relation.

Abstract: A vehicle drive control device includes an initially determined request acceleration calculation means for calculating an initially determined request acceleration, an automatic drive control means for receiving the initially determined request acceleration and applying a predetermined torque to each wheel, a torque calculation means for calculating an allowable torque not causing a slip at each wheel when the allowable torque is applied thereto, on the basis of a vertical load applied to thereto and a friction coefficient of a road surface, a limit acceleration calculation means for calculating a limit acceleration acting on the vehicle in a case where the calculated allowable torque is applied to each wheel, and a request acceleration determination means for obtaining a request acceleration on the basis of the limit acceleration and the initially determined request acceleration, and for outputting the request acceleration, replacing the initially determined request acceleration, to the automatic drive contr

Abstract: A slip control apparatus includes a driving torque calculating means calculating driving torque, a driving torque applying means applying the calculated driving torque to driving wheels, and a slip restraining means restraining slippage at each driving wheel when the slippage occurs at each driving wheel, wherein when the slippage occurs at each driving wheel, the driving torque calculating means calculates demanded torque and adds consumed driving torque, which corresponds to the driving torque consumed for restraining the slippage at each driving wheel by the slip restraining means, to the calculated demanded torque to calculate the driving torque.

Abstract: In a method for characterizing a road surface beneath a moving vehicle whose powertrain includes a torque converter coupling the engine to a driven wheel, a set of successive values for the torque converter's slip error rate is generated using filtered values for engine speed and torque converter turbine speed. The road surface characteristic is identified based on the set of slip error rate values, as through a comparison of the set with a plurality of case statements, wherein each case statement corresponds with a different road characteristic and/or general surface type. Weighted average values are calculated based on subsets of the values within the set, for use in identifying transitions from one type of surface to another, or one surface characteristic to another. Indicated slip error rates generated in response to changes in an engine torque demand request are also identified to avoid a false indication.

Abstract: A dynamic characteristic of a hydraulic pressure is significantly enhanced since a line pressure control system. A method employed by the system includes determining whether a vehicle is in a power-on state, determining whether a damper clutch is being engaged when the vehicle is in the power-on state, compensating a line pressure duty determined on the basis of an engine torque with a first compensation duty determined on the basis of a vehicle speed and an operation state of the damper clutch when the damper clutch is being engaged under the power-on state, and controlling the line pressure according to the compensated line pressure duty.

Abstract: A method of controlling a vehicle drive system is provided for a vehicle having an internal combustion engine, free-wheeling steerable front wheels, driven rear wheels, an infinitely variable transmission (IVT) transmitting torque from the engine to the rear wheels, and a control unit for controlling the IVT as a function of sensed parameters and supplying a speed command to the IVT for commanding a speed of the rear wheels. The method includes sensing a steering angle of the front wheels, sensing a front wheel speed, sensing a rear wheel speed, generating a corrected estimated vehicle speed as a function of the front wheel speed and the sensed steering angle, and increasing the speed command in response to a comparison between the corrected estimated vehicle speed and the rear wheel speed. The infinitely variable transmission is preferably embodied by a hybrid electric drive system.

Abstract: A system for controlling slip of vehicle drive members is disclosed. The system includes a power train including a plurality of drive members and a hydraulic transmission configured to supply torque to at least one of the drive members. A magnitude of the torque is related to fluid flow in the hydraulic transmission. The system further includes a controller configured to control the fluid flow in the hydraulic transmission. The controller is configured to receive a signal indicative of a steering command and a signal indicative of a parameter related to pressure in the hydraulic transmission. The controller is further configured to control slip of the at least one drive member based on the signal indicative of a steering command and the signal indicative of a parameter related to pressure.

Abstract: Under the condition of a large variation Tm in motor torque demand Tm*, the significant torque change may lead to some vibration of a vehicle to temporarily heighten an angular acceleration. The temporary rise of the angular acceleration may cause the angular acceleration to exceed a preset threshold value slip and result in misdetection of the occurrence of a ‘phantom’ skid in an angular acceleration—based skid state determination (step S112). The drive control of the invention accordingly specifies a potential for misdetection of the occurrence of a ‘phantom’ skid when the variation Tm in motor torque demand Tm* exceeds a preset threshold value Tthr at step S108. The drive control thereby does not execute skid occurring state control (step S120) with torque restriction but performs grip state control at step S116.

Abstract: A method for temporarily preventing automatic gear shifting in a vehicle, comprising the steps of: preventing gear shifting as long as a traction control system indicates that at least one driven wheel is spinning, calculating a vehicle acceleration, calculating a value of a derivative of the acceleration or a value indicative of a difference between the vehicle acceleration and a previously calculated vehicle acceleration, and preventing gear shifting for a predetermined time, if the value is equal or higher than a predetermined value. A system, a computer program, a computer program product and an electronic control unit for performing the method are also disclosed.

Abstract: A drivetrain protection and management system (DPMS) monitors and determines individual wheel speeds to detect wheel spin and slip conditions on a drive axle. Wheel spin is caused by low surface friction, excessive input torque, lack of inter-axle differential and differential locks, excessive operating temperatures, or poor driving techniques. When wheel spin or slip exceeds a threshold, the DPMS automatically controls input torque to the drive axle by controlling engine or retarder torque. In addition to monitoring wheel speeds, the DPMS monitors other vehicle characteristics such as engine torque/speed, transmission ratio, transmission output speed, vehicle speed, throttle position, for example. The DPMS monitors and stores these vehicle characteristics over time and generates a data output that summarizes a history of vehicle operating conditions. The DPMS can communicate this data output real time during vehicle operation, which can be used by a fleet to maximize vehicle performance.

Abstract: A multivariable feedback control approach to actively dampen magnitude of jerks in a powertrain system using multiple torque-control devices is offered. To manage jerks, a desired axle torque is restricted when a torque reversal occurs. When the vehicle operator or the system executes a command that requires change in direction of torque, the desired axle torque is limited to a low level until the lash estimate has changed accordingly. During this transition time, active damping controls driveline component speeds so that the effect of lash take-up is minimized. After lash take-up occurs, the desired axle torque proceeds without restriction. The invention includes determining a desired axle torque, an output speed of the transmission, and an output speed of a driven wheel of the driveline. One of the devices is controlled based upon a time-rate change in the desired axle torque.

Abstract: Method and arrangement for automated control of a drive train (10) of a land vehicle to be executed when ground conditions exist that impede the initiation or continuation of travel of the vehicle such as being stuck on loose or slippery ground. The automated routine induces a rocking action in the vehicle purposed to aid in freeing the vehicle and permitting desired travel out of the area. As an initial step of the routine, it is determined whether such a ground condition exists. If so, drive power is applied, via a drive train (10) of the vehicle until the drive wheel (26, 30) bogs down or productive and continuous travel is established in the vehicle. A rocking-back action is permitted by a discontinuation of the drive power to the drive wheel (26, 30) of the land vehicle until a predetermined power resumption condition occurs. Reverse power can be optionally applied at this time. Otherwise, drive power is reapplied to the drive wheel (26, 30) for another attempt at forward progress.

Abstract: The magnitude of torque which can be transmitted by a bypass clutch between the housing and the turbine of a torque converter between a prime mover, such as an engine, and an automatic transmission in the power train of a motor vehicle is selectively regulatable by a computerized regulating unit. The regulation involves the transmission of torque by the clutch in dependency upon the magnitude of the torque being transmitted by the output element of the engine and ascertaining as well as adaptively applying to the clutch a variable force so that the clutch can transmit a predetermined torque. This entails automatic selection of a minimum slip between a torque receiving and a torque transmitting part of the power train. Compensation, particularly long-range compensation, is carried out for the existence of possible differences between the predetermined and actual torques being transmitted by the clutch.

Abstract: A method a operating a traction control system using a traction controller (30) for an automotive vehicle (10) is provided. A slip target is first determined. Then, an operating temperature turning characteristic or slope of the slip curve may, in combination or alone, be used to adjust the slip trigger threshold above the slip target. Traction control mode is entered when the driven wheel speed is above the slip trigger threshold.

Abstract: An apparatus for controlling driving forces supplied to left and right wheels of a vehicle, for effectively inhibiting oversteer and understeer states, includes driving force adjusting device for adjusting driving forces supplied to the left and the right rear wheels, first controlling device for controlling the driving force adjusting device such that a wheel speed difference between the left and the right rear wheels coincides with a target wheel speed difference, and second controlling device for controlling the driving force adjusting device such that a yaw momentum of the vehicle coincides with a target yaw momentum. If the vehicle is in an understeer state, the contribution of the second controlling device is increased relative to that the first controlling device and if the vehicle is in an oversteer state, the contribution of the first controlling device is increased relative to that of the second controlling device.

Abstract: A method and apparatus to control acceleration of a vehicle equipped with an electrically variable transmission and including a regenerative braking system, each are operably connected to a vehicle driveline. The method and apparatus include determining which one of a preselected shift selector position for the transmission is commanded, and determining operator demand for acceleration, using inputs from throttle pedal and brake pedal. Vehicle acceleration is measured, and magnitude of commanded torque transferred from the electrically variable transmission and the regenerative braking system to the vehicle driveline is controlled based upon the commanded preselected shift selector position, the operator demand for acceleration, and the measured vehicle acceleration.

Abstract: A power-assisted steering system includes: two or more current detectors that detects current flowing to two or more phases of a motor and outputs detected current values; a correcting unit that corrects the detected current values output from the current detectors to compensate a difference in gain between the current detectors; and a motor driving driver that drives the motor based on a deviation between the target current value and corrected detected current values. When the same current flows to the phase in which the current flowing thereto is detected by the reference current detectors and the phase in which the current flowing is detected by the other current detector, the correcting unit calculates a gain correcting coefficient based on a detected current value of the reference current detector and a detected current value of the other current detector and corrects the detected current value of the other current detector.

Abstract: The invention includes a target-engine-speed acquisition element that acquires a target engine speed necessary to reduce engine speed, thereby stopping the engine at a target stop position; a crank-angle acquisition element that acquires a crank angle indicative of the position of a crankshaft; and a target-engine-speed correction element that corrects the target engine speed according to the acquired crank angle. Because the target engine speed is corrected according to the crank angle, the engine can be stopped at the target stop position even if the friction in the engine, the electric motor, etc. varies, the temperature or viscosity of the lubricating and cooling oils varies, or the vehicle is accelerated or decelerated during the reduction of the engine speed.

Abstract: A vehicular powertrain has output torque established in accordance with various torque contributions in including throttle and brake torques. Throttle torque contribution is reduced proportionally to the amount of brake torque requested. Furthermore, such torque reductions are less aggressively applied with increasing throttle torques requested.

Abstract: A method for providing traction control in vehicle powertrain systems is particularly adapted for traction control in a powertrain system of a hybrid electric vehicle comprising an internal combustion engine, an electric machine and a transmission that is operatively coupled to the electric machine and the engine and adapted to provide a transmission torque output in response to a transmission torque input received as a torque output from either or both of the engine and the electric machine. The method is adapted to utilize conventional traction control and engine control hardware, software and communication standards to implement traction control. In one embodiment of the invention, a conventional traction controller is used to detect a wheel spin condition and provide a plurality of first output torque command messages in response thereto.

Abstract: The invention relates to torque sensors or more particularly to automotive torque sensors which measure the torque transmitted at one or more positions within an automotive power train. The invention provides a method for zeroing an automotive power train torque sensor while a vehicle is moving during the zero torque condition.

Abstract: A device for uphill start-up assistance for a motor vehicle including a control for controlling release of the vehicle mechanical brakes that act on the vehicle wheels, so that the vehicle is maintained on the slope when maneuvering uphill without any intervention from the driver on this maintaining condition. The control uses mainly the state of the slope, the interpretation and anticipation of the commands of driver and/or of a central driving member, and the determined instantaneous clutching characteristics. In a preferred embodiment, the assistance device co-operates with an electrical device of the parking brake.

Abstract: A control system limits reactive torque in a powertrain that is generated when braking force is applied to traction wheels during a sudden stop or other sudden braking event. The reactive torque generated at the traction wheels is prevented from being transmitted upstream through the driveline and powertrain by using a slip type clutch in the driveline to limit the upstream transfer of the reactive wheel torque. The clutch is directly actuated by the reactive torque and therefore does not require special controls or monitoring systems to sense the braking event. The clutch pressure may be automatically adjusted in response to certain operating conditions or events, thereby adjusting the point at which the clutch begins to slip due to reactive wheel torque.

Abstract: An electronic control unit calculates a target yaw rate in accordance with a vehicle speed and a steering angle and calculates the yaw rate difference on the basis of the target yaw rate and an actual yaw rate. The electronic control unit estimates the grip factor of a front wheel to road surface and sets a distribution ratio for distribution of a vehicle-control target value among actuators of a steering system, a brake system, and a drive system in accordance with the estimated grip factor. The electronic control unit controls the actuators of the three systems in accordance with control instruction values distributed on the basis of the vehicle-control target value and the distribution ratio.

Abstract: A driver-initiated low traction control method limits the drive torque of a motor vehicle during operation on low traction road surfaces. The low traction control mode is initiated by actuation of a switch or by moving a transmission range selector to a Low range while the vehicle is substantially stopped, and terminated by further actuation of the switch or by returning the range selector back to the Drive setting. The low traction control mode limits the engine torque as required to limit the drive wheel torque and its rate of change, so long as cruise control is inactive, the accelerator pedal setting is less than a reference level, and the transmission is operating in a gear other than its top gear. When the low traction control mode is terminated, the engine torque limits are progressively removed in a way that does not produce perceptible acceleration or deceleration of the vehicle.

Abstract: A vehicle is provided with an engine (1), an automatic transmission (2) connected to the engine (1), a detection device (21–24, 31) which detects an operating state of the transmission (2), and a torque regulating mechanism (1a, 1b, 1c) which regulates a torque of the engine. When the operating state of the transmission (2) is in a predetermined drive state and the torque of the engine (1) is to be reduced, a selection is made, based on the operating state of the transmission (2), between a first torque reduction control whereby the torque of the engine (1) is reduced rapidly and temporarily, and a second torque reduction control whereby the torque of the engine (1) is reduced continuously, and more smoothly than in the first torque reduction control. The torque of the engine (1) is then reduced by the selected one of the first torque reduction control and the second torque reduction control.

Abstract: An engine control system and method adjusts vehicle driveability based on input from a vehicle operator. A selector switch includes a plurality of selector settings corresponding to a plurality of drive modes. The selector switch is moveable between the plurality of selector settings by the vehicle operator. A controller communicates with the selector switch and includes a plurality of predetermined drive settings corresponding to the plurality of drive modes. The controller utilizes predetermined transmission shift points, torque converter slip and throttle position progression data based on a current selector setting chosen by the vehicle operator.

Abstract: A slip control system of a lockup torque converter includes a pre-compensator that pre-compensates for a target slip-rotation speed to produce a target slip-rotation speed correction value. A feedback compensator is provided to feedback-control an engagement capacity of a lock-up clutch based on a deviation between the target slip-rotation speed correction value and an actual slip-rotation speed to bring the actual slip-rotation speed closer to the target slip-rotation speed. Also provided is a dead-time processing section that compensates for the target slip-rotation speed correction value to reflect a dead time of dynamic characteristics peculiar to the slip control system in the target slip-rotation speed correction value. The dead-time compensated output is fed to the feedback compensator. The dead time is variable in accordance with a predetermined dead time characteristic.

Abstract: In a method of controlling an internal combustion engine, at least one operating variable is controlled, a pre-control ignition timing efficiency is formed as a function of operating parameters of the engine and/or external intervention measures, and the pre-control ignition timing efficiency determines the setpoint values of the at least one operating variable. In a transition from a first operating state to a second operating state, the pre-control ignition timing efficiency is varied by a transition function.

Abstract: A torque distribution control device for a four-wheel drive vehicle has a torque distribution device for distributing the drive power transmitted from an engine to either of the front wheels or the rear wheels as prime drive wheels, to other wheels as sub-drive wheels. The control device judges whether or not an abnormality is involved in wheel speed signals which are input from wheel speed sensors associated respectively with the front and rear wheels. A normal-state method of calculating a command torque which is applied to the torque distribution device to vary the drive power transmitted to the sub-drive wheels, is then altered to an abnormal-state method of calculating the command torque based on data which does not include one wheel speed signal involving the abnormality when the same occurs with one of the wheel speed signals, whereby the vehicle is enabled to continue the four-wheel drive even when the abnormality occurs.

Abstract: A method and an arrangement for controlling the drive unit of a vehicle are suggested. In a first step, input quantities, which are independent of the drive unit, are applied to form a first input quantity. In a second step, a second input quantity is formed from at least this first input quantity and at least one engine-specific input quantity, the second input quantity influencing at least an actuating quantity of the drive unit. In addition, an interface is described between the engine-independent part and the engine-specific part of the engine control.

Abstract: A control system that senses misalignment of components in a vehicle drive train system and adjusts the vehicle ride height to realign the components. A control unit monitors vibration, torque or other operating parameters of a vehicle's drive train or other vehicle components and determines whether the parameters are abnormal. If the monitored parameters are abnormal, then the control unit controls suspension elements on the vehicle to adjust the ride height of the vehicle and subsequently the alignment of the drive train, for example, the operating angle of the driveshaft. A ride height sensor feeds back ride height measurements as the suspension elements are adjusted to assist in finding an optimal ride height that eliminates or reduces excess vibration and/or torque. In another embodiment, the control unit adjusts the ride height based on vehicle speed or fuel economy to reduce the profile of the vehicle and improve fuel economy.

Abstract: A control apparatus for a friction device of a vehicle that is disposed in a power transmission path of the vehicle and is adapted to be engaged upon a start of the vehicle is provided. The control apparatus controls the engagement pressure of the friction device so as to eliminate a pulsation component contained in variations in an engagement torque of the friction device.

Abstract: An apparatus and a method for controlling an automotive vehicle are disclosed, in which a control amount for securing safety of the vehicle and the control amount for achieving a state intended for by the driver of the vehicle are switched in such a manner as to reduce the shock due to the change in the torque generated from the power train, thereby accomplishing both safety and maneuverability at the same time. A first target value is set for controlling at least selected one of the driving torque, the driving force and the acceleration/deceleration rate. A second target value is calculated in accordance with the drive mode intended for by the driver or the driving environment ahead of the vehicle. In the case where a deviation exceeding a predetermined value develops between the first target value and the second target value, the fluctuations of at least one of the driving torque, the driving force and the acceleration/deceleration rate are suppressed.

Abstract: In the method for kick-down switching speed optimization in a motor vehicle with an automatic transmission, the kick-down upshift point is determined as a function of the load conditions and the road inclination in each case.

Abstract: A slip control system of a lockup torque converter includes a pre-compensator that pre-compensates for a target slip-rotation speed to produce a target slip-rotation speed correction value. A feedback compensator is provided to feedback-control an engagement capacity of a lock-up clutch based on a deviation between the target slip-rotation speed correction value and an actual slip-rotation speed to bring the actual slip-rotation speed closer to the target slip-rotation speed. Also provided is a dead-time processing section that compensates for the target slip-rotation speed correction value to reflect a dead time of dynamic characteristics peculiar to the slip control system in the target slip-rotation speed correction value. The dead-time compensated output is fed to the feedback compensator. The dead time is variable in accordance with a predetermined dead time characteristic.

Abstract: The invention is directed to a method and an arrangement for controlling a drive unit (1) of a motor vehicle. The method and arrangement reduce the lost motion of an operator-controlled element (5), which is actuable by the driver, up to an increase of the road speed of the vehicle beyond the road speed pregiven by the road speed controller (10). The degree of actuation (F) of the operator-controlled element (5) is detected and a desired value (S) for the torque of the drive unit (1) is formed from this degree of actuation (F). The desired value (S) for the torque is compared to a pregiven value (V) for the torque requested just then by the road speed controller (10). The torque of the drive unit (1) can only then approach the desired value (S) via control of the drive unit (1) when the desired value (S) exceeds the input value (V).

Abstract: A control unit of a control system for wheel-specific braking torque control is provided for a vehicle having an electronically controlled transmission. The control unit records the speeds of all wheels of the vehicle for the purpose of recognizing wheel slippage. The control unit records at least one vehicle dynamics operating parameter of the vehicle as an input signal, which can be recognized by a yawing of the vehicle. In the case of slippage on at least one wheel of an axle and when yawing of the vehicle takes place, the control unit initiates an up-shifting process in the transmission in order to reduce the engine torque by a certain torque amount. At the same time, the control unit initiates a braking intervention on both wheels of the other axle, i.e. the axle without the wheel slippage, in order to increase the braking torque by the same torque amount.

Abstract: Method for restoration of the drive torque during a change of gear, wherein the clutch is closed in order to adjust the angular speed of the drive shaft to match the angular speed of the primary shaft of the gearbox; when the angular speed of the drive shaft is close to the angular speed of the primary shaft of the gearbox, a reference profile is generated for the angular speed of the drive shaft, and the drive torque generated by the engine is controlled in order to make the angular speed of the drive shaft follow the reference profile, which has a final portion which is substantially tangent to the angular speed of the primary shaft of the gearbox.

Abstract: A powertrain system (10) control for controlling engine (12) output torque as a function of engaged ratio of a transmission (14). Separate torque limits, A, B, C, D, respectively, are set for start ratios, intermediate ratios, direct ratio and overdrive ratios. The torque limits are set such that A<B<C>D and B<D.

Abstract: A method of controlling an automatic transmission of a motor vehicle operating in a automatic speed control speed mode is provided. The first step in the method is measuring the torque output of the engine. A torque load acting on the transmission in a first gear is then determined. A maximum torque capable of being produced by the engine is then predicted. A torque output of the transmission in a second gear is then determined based upon the predicted maximum torque capable of being produced by the engine. A transmission shift from the first gear to the second gear is then allowed if the determined torque output of the transmission in the second gear is greater than the torque load of the transmission in a first gear.

Abstract: The invention relates to a method for control of an automatic transmission of a motor vehicle wherein an electronic transmission control, by means of signals proportional to wheel speeds (NRA3, NRA4), determines a transverse acceleration value (AQ) for outputting to additional program modules. The determined wheel speeds (NRA3, NRA4) which enter in the transversal acceleration value (AQ) are corrected by vehicle wheels in a tolerance balance module of the wheels (M1) when a dynamic tire radius (RDYN) in one of the vehicle wheels diverges from a tire radius given in an optimum tire geometry.

Abstract: A method is described for limiting a change in torque transmitted through a vehicle powertrain when in a predetermined range. Such a method minimizes transmission gear separation, or “clunk”. In one approach, the rate cf change of powertrain output is limited when powertrain output is near zero transmitted torque. The limitation is not used under other circumstances so as not to hinder driver performance.

Abstract: When a road surface gradient is calculated by a wheel driving force and a vehicle acceleration, if the wheel driving force is calculated based on an output torque of an engine, the accuracy of calculating the wheel driving force, i.e., the road surface gradient becomes poor due to deterioration by aging of the engine or the like. In order to solve this kind of disadvantage, a fluid transmission torque of a torque converter is calculated by those torque ratio of the torque converter and an input shaft torque coefficient which correspond to a speed ratio of the torque converter, and an input rotational speed of the torque converter (=engine rotational speed (step S21-3). The road surface gradient is calculated by using a wheel driving force to be calculated by this torque.

Abstract: An arrangement and a method for a drive unit of a vehicle. The drive unit incorporates an engine, a mechanical stepped gearbox and a connecting device which is designed to transmit rotary motion from the engine to the stepped gearbox. An electric rotor machine acts upon the connecting device such that substantially no torque is transmitted from the engine to the gearbox during gear changing. A control unit connected to the rotor machine may be responsive to the output shaft from the gearbox or to the speed of the engine.

Abstract: To achieve a first object of the present invention, a starting time limit vehicle speed which preferentially permits a torque distribution to front and rear wheels at the time of starting of a vehicle is switched in accordance with a degree of a diameter difference. To achieve a second object of the present invention, when the vehicle makes a normal running with different-diameter tires mounted thereon, a front/rear wheel distribution torque caused by a front/rear wheel rotation speed difference owing to the different-diameter tires is limited by switching a torque gain depending on a degree of a diameter difference.

Abstract: A process for continuously controlling the transfer of torque within a differential where a target delta (&Dgr;T) value is determined as a function of a first differential output shaft speed (&ohgr;a) and a second differential output shaft speed (&ohgr;b) and then normalized according to the vehicle speed when the vehicle is being driven under a no wheel slip condition. A normalized actual delta (&Dgr;A) is also determined as a function of the first output shaft speed (&ohgr;a) and the second output shaft speed (&ohgr;b), a comparison is made between &Dgr;T and &Dgr;A and torque is transferred between the first and second output shafts of the differential according to a logic control methodology such as proportional, integral, and/or derivative (PID) control methodologies if the comparison result of &Dgr;A to &Dgr;T is outside of a tolerance range established around &Dgr;T.

Abstract: An apparatus for determining a failure of wheel speed sensors, which is capable of properly determining whether or not a wheel speed detection system including the wheel speed sensors has failed, if at least a wheel speed detected by the wheel speed sensors indicates a stopped state of a corresponding wheel. An engine rotational speed is detected, and an input-output rotational speed ratio of a torque converter of an automatic transmission mounted in the vehicle is calculated. A shift range of the automatic transmission is detected. Whether or not the vehicle is traveling is determined based on the engine rotational speed and the input-output rotational speed ratio when the automatic transmission is in a traveling range. It is determined that the wheel speed detection system including the wheel speed sensors has failed, if it is determined that the vehicle is traveling, and at the same time, at least one of wheel speed sensors indicates a stopped state of a corresponding one of the wheels.

Abstract: An apparatus for controlling an automatic transmission of an automobile and a control method thereof. When a feedback control is executed by the automatic transmission while the speed is being changed, the control operation may often lose stability. This is due to a large deviation between a target value and a practical value at the start of the feedback control operation being caused by a change in the opening degree of the throttle and a change in the oil temperature in the automatic transmission. To solve such a technical problem, the invention employs a control apparatus which detects that the automatic transmission is changing the speed, operates the output shaft torque of the automatic transmission, recognizes a point of inflection of the output shaft torque while the speed is being changed, sets a target output shaft torque of the automatic transmission, and sets an initial target value at a moment of said point of inflection.

Abstract: A vehicle traction control increases the allowed wheel spin for a driven wheel when (1) sensed vehicle speed is within a predetermined speed range corresponding to near maximum engine speed for the sensed currently used gear of the transmission, (2) sensed vehicle turn curvature is within a predetermined curvature range of zero curvature, (3) sensed vehicle longitudinal acceleration has not been below a predetermined high acceleration for a predetermined time, and (4) sensed vehicle engine speed has not been below a predetermined high engine speed for the predetermined time. The tests are calibrated to provide the increase in a very narrow range of conditions corresponding to high performance operation, and particularly power shifts of a manual shift transmission, on a racetrack with a high coefficient surface.