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 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 is proposed for blocking inadmissible gearshift processes in a transmission with a plurality of shifting devices which, to carry out a shift process, are moved by actuating devices when a shift command is sent by a control unit (TCU) to the relevant actuating device. The actuating devices are connected for data exchange with one another and with the control unit (TCU) in such manner that the actuating device of the shifting device to be shifted is activated provided that clearance has been given by at least one other actuating device.

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: The line hydraulic pressure setting portion sets the line hydraulic pressure PL, which is the base pressure for the required shift control pressure Pin and the required belt clamping pressure Pd, based on the higher of the required pressures Pin and Pd. At this time, if the continuously variable transmission is to be shifted up, the required Pin calculating portion calculates the required shift control pressure Pin based on one of the target speed ratio ?* and the actual speed ratio ? with which the required shift pressure Pv is calculated to be higher than with the other. As such, the required shift control pressure Pin is set to the minimum necessary level for shifting up the continuously variable transmission and the line hydraulic pressure PL is appropriately set to a level for obtaining the required shift control pressure Pin.

Abstract: A powertrain control includes monitoring map preview information, determining a road gradient factor based upon the map preview information, and adapting a transmission shift schedule based upon the road gradient factor.

Abstract: A method for controlling a vehicle's automated transmission, which is arranged in a drive train in the force flow between a engine and a drive axle or a transfer box, depending on certain operating parameters and control actions of an adaptive cruise control system (ACC) that can be operated using engine and brake mechanisms to regulate speed and distance from a car in front. The method controls the transmission when an engine torque demand differs from the torque demand of the ACC. The operating mode of the ACC, which is active at the time, and the load direction of the torque demand of the ACC are determined, and the torque demand, used for controlling the transmission when speed or distance regulation is activated, is determined depending on the ACC operating mode and the load direction of the torque demand.

Abstract: The invention concerns a method for controlling automatic transmission (3) of a vehicle comprising an engine (2) driving the transmission (3) which consists in: detecting a downhill situation of the vehicle, and selecting a transmission ratio so that the engine absorbs energy, storing a longitudinal speed of downhill start (Vmin) when the vehicle starts going downhill, and while the vehicle is running downhill, comparing the current speed (V) of the vehicle with the downhill start speed (Vmin) such that the current speed (V) exceeds the downhill start speed (Vmin) by a predetermined difference (VS), then controlling the transmission to trigger downshifting.

Abstract: A method for controlling a power-shift transmission comprising controlling a vehicle travel speed by simultaneously slipping two or more clutch packs associated with opposing directions of vehicle travel and adjusting an engine speed, according to a programmed response associated with a change in one or more of the engine speed, a torque converter slip, a selected direction of vehicle travel, and an accelerator position.

Abstract: A vehicle control method for a vehicle having an internal combustion engine coupled to a torque converter is described. In one embodiment, the engine air flow and spark are adjusted to control torque converter operation. The method can improve vehicle response to driver accelerator commands.

Abstract: A drive system is provided for a utility vehicle and includes an alternating-current (AC) motor for providing a drive torque. An AC motor controller receives a battery voltage signal, throttle pedal position signal, brake pedal position signal, key switch signal, forward/neutral/reverse (FNR) signal, and run/tow signal indicative of the utility vehicle being configured to be driven and being configured to be towed. The AC motor controller generates an AC drive signal for the AC motor, wherein the AC drive signal is based on the battery voltage signal, throttle pedal position signal, brake pedal position signal, key switch signal, FNR signal, and run/tow signal.

Abstract: Vehicular drive system which is small-sized and/or improved in its fuel economy. A power distributing mechanism 16, which is provided with a differential-state switching device in the form of a switching clutch C0 and a switching brake B0, is switchable by the switching device between a differential state (continuously-variable shifting state) in which the mechanism is operable as an electrically controlled continuously variable transmission, and a fixed-speed-ratio shifting state in which the mechanism is operable as a transmission having a fixed speed ratio or ratios. The power distributing mechanism 16 is placed in the fixed-speed-ratio shifting state during a high-speed running of the vehicle or a high-speed operation of engine 8, so that the output of the engine 8 is transmitted to drive wheels 38 primarily through a mechanical power transmitting path, whereby fuel economy of the vehicle is improved owing to reduction of a loss of conversion of a mechanical energy into an electric energy.

Abstract: A powertrain controller for a vehicle comprises a vehicle load estimation module, an adaptive power demand module, a throttle map module, and a transmission gearshift map module. The adaptive power demand module selects one of N mappings from pedal position to power demand based upon a vehicle load index and determines a power demand signal based upon a received pedal position signal and the selected one of the N mappings. The throttle map module selects one of P mappings from speed to throttle control based upon the power demand signal and determines a throttle control signal based upon a received speed signal and the selected one of the P mappings. The transmission gearshift map module selects one of Q mappings from vehicle speed to gear selection based upon the power demand signal and determines a gear control signal based upon a received vehicle speed signal and the selected one of the Q mappings.

Abstract: A vehicle speed control system for controlling a vehicle on a chassis dynamometer is comprised of a controller which is arranged to receive a vehicle speed command, to obtain an anticipated vehicle speed command from the vehicle speed command taking account of a delay factor of a control system of the vehicle, to calculate a driving force a driving force command from the anticipated vehicle speed command, to obtain an accelerator opening command from a previously stored driving force characteristic map based on the driving force command and a detected vehicle speed, and to control an accelerator opening of the vehicle according to the accelerator opening command so as to adjust the detected vehicle at the vehicle speed command.

Abstract: A wheel speed detection system including a rotator, a sensor head, a detector, a pulse converter, a speed calculator and a threshold shifter. Plural concave and convex portions are formed on a periphery of the rotator rotating together with a wheel. The sensor head includes a coil to generate an alternate current magnetic field. The detector excites the coil to generate an eddy current on the concave and convex portions, and outputs alternate current detection signals corresponding to changes in the eddy current generated with rotation of the rotator. The pulse converter converts the alternate current detection signals into pulse signals according to preset threshold levels. The speed calculator calculates rotational speed of the wheel based on the pulse signals. The threshold shifter shifts the threshold levels corresponding to a difference between a default average and an average of the alternate current detection signals actually outputted from the detector.

Abstract: A vehicle control method for transitioning through transmission lash regions is described using a variety of information, such as, for example, gear ratio, clutch slippage, etc. Further, different adjustment of spark and throttle angle is used to provide a rapid torque response while still reducing effects of the lash. Finally, transitions taking into account both slipping and non-slipping transmissions are described.

Abstract: The following steps are performed in the control method: determining a mode of operation from amongst a permanent mode and a transient mode, as a function of a set of variables comprising said estimated values; correcting the value of the speed of rotation of the outlet shaft in such a manner that: if the mode has been determined as being the permanent mode, then the moving average (L?) of the gear ratio (L) over a period (T) of a plurality of unit time intervals lies between a first threshold value (S1) that is negative and a second threshold value (S2) that is positive; and if the mode has been determined as being the transient mode, then said moving average (L?) of the gear ratio (L) lies outside the range of values defined by the first and second threshold value (S1, S2).

Abstract: A method for controlling selection of an automatic transmission gear ratio with staged ratios or constant variation for a vehicle including a control for preventing/allowing extension of the gear ratio or for controlling a shortening the transmission gear ratio if, at a current engine speed, the power is insufficient for maintaining the vehicle speed. The method prevents extension of the transmission gear ratio if the power available after the extension is insufficient for maintaining the vehicle speed; otherwise allowing extension of the transmission gear ratio.

Abstract: A method for gear selection during driving of a vehicle in a heavy uphill drive condition is provided, the vehicle including an engine, an automated mechanical transmission, a clutch, a control unit for receiving input signals including signals indicative of vehicle speed, engaged ratio of the transmission, rotational speed of the engine, rotational speed of a input shaft and displacement of a throttle control for engine torque request, and for processing the signals in accordance with programmed logic rules to issue command output signals to the engine, to the transmission and to said clutch.

Abstract: An adaptive position kick-down detent mechanism for providing a force feedback to an operator of a vehicle through a drive-by-wire accelerator prior to the transmission performing a kick-down. The kick-down detent mechanism includes a plunger portion, a plunger driving device, and an elastic portion. The plunger portion is slidable within the plunger driving device and is biased by the elastic portion. An electronic control unit communicates a kick-down pedal position to the plunger driving device, which moves the plunger portion to the kick-down pedal position so that the force feedback is provided to the driver before the kick-down even as the kick-down pedal position changes during vehicle operation.

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: A vehicle cruise control system is provided that comprises a vehicle speed detecting section, a cruise control section, and a cruising speed setting section. The vehicle speed detecting section is configured and arranged to detect a speed of a host vehicle. The cruise control section is configured to execute a first prescribed cruise control such that the host vehicle travels in a constant-speed state at a cruising speed setting when the host vehicle is traveling in a first prescribed speed region. The cruising speed setting section is configured to set the cruising speed setting when the host vehicle is traveling in a vehicle speed region other than the first prescribed speed region.

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 warning apparatus for a vehicle determines a contact possibility of the vehicle contacting with an object that is present in front of the vehicle according to a relative distance between the vehicle and the front object, a relative speed between the vehicle and the front object, and the like, and provides a contact possibility warning by changing at least one of the driving torque and braking torque of the vehicle according to the contact possibility. The warning apparatus detects, an intention of the driver of the vehicle to bring the vehicle closer to the front object in a steady driving state of the vehicle by, for example, changing a lane of the vehicle. The warning apparatus calculates a correction value to change the driving torque or braking torque according to a result of the detection, delays the timing of providing the contact possibility warning, and controls braking force.

Abstract: A speed regulator for motor vehicles, including a standard mode in which the speed is regulated to a desired speed set by the driver, and at least one exception mode in which the speed is regulated to a setpoint speed that may deviate from the desired speed, and a display device for displaying the desired speed. An auxiliary display is also provided that indicates that an exception mode is active.

Abstract: A predictive load management system is provided. A power source is operable to generate a power output and has a desired operating range. A transmission has a drive member operably engaged with the power source and a driven member. A control system is operable to receive at least one input indicative of a load on the transmission and to identify a desired load of the transmission based on the at least one input. The control system is also operable to receive at least one input indicative of current power output of the power source. The control system limits the desired transmission load applied to the driven member of the transmission based on the current power output of the power source to thereby prevent the power source from operating outside of the desired operating range.

Abstract: A method is directed to the control of the speed of a vehicle wherein the actual speed is caused to track the desired speed. For reducing the actual speed, a transmission (1) of the vehicle (5) is driven to downshift and thereby the brake system is protected with respect to wear and overheating.

Abstract: Control method for effecting a gear shift in a stepped automatic transmission with an input shaft and an output shaft for transmitting power between two inertia components at distinct speed ratios with a first power transmission path and a second power transmission path being provided with a high clutch having an adjustable torque transmitting capacity TH and a low clutch having an adjustable torque transmitting capacity TL respectively. The method includes the steps of determining a gear set input torque Tin to be transmitted by the transmission in the direction from the input shaft to the output shaft and controlling the torque transmitting capacities TH and TL in dependency on the gear set input torque Tin to be transmitted such that: a) if Tin>=0 then TH=Tin and TL=0 b) if Tin<0 then TH=0 and TL=Ti.

Abstract: An engine and transmission control system is responsive to manipulation of manually operated control devices which can cause actions which result in increased load on the vehicle engine, before the engine actually begins to be effected by the load increase. The control system monitors manipulation of control devices and engine load, and when engine load decreases, the system stores the identity and displacement direction of the manipulated control device. When the same control device is then manipulated in the opposite direction, the control system will begin to temporarily boost or raise engine rpm and decrease the transmission ratio in anticipation of the expected load. After the control system has boosted the engine rpm, it monitors whether or not the engine speed was boosted high enough to prevent the engine speed from dropping below a threshold.

Abstract: A cruise control system is adapted to a vehicle equipped with an internal combustion engine and a manual transmission which are disengageably connected through a clutch. The cruise control system is arranged to calculate a first vehicle operation indicative quantity based on an engine speed detected by an engine speed sensor, to calculate a second vehicle operation indicative quantity based on a wheel speed detected by a wheel speed sensor, to determine whether a deviation between the first vehicle operation indicative quantity and the second vehicle operation indicative quantity is greater than a predetermined value, and to cancel the cruise control when the deviation is greater than the predetermined value.

Abstract: An engine and transmission control system is responsive to manipulation of manually operated control devices which can cause actions which result in increased load on the vehicle engine, before the engine actually begins to be effected by the load increase. The control system monitors manipulation of control devices and engine load, and when engine load decreases, the system stores the identity and displacement direction of the manipulated control device. When the same control device is then manipulated in the opposite direction, the control system will begin to temporarily boost or raise engine rpm and decrease the transmission ratio in anticipation of the expected load. After the control system has boosted the engine rpm, it monitors whether or not the engine speed was boosted high enough to prevent the engine speed from dropping below a threshold.

Abstract: A transmission system includes a Central Processing Unit (CPU) that controls truck braking energy by sharing energy dissipation between clutch packs. The CPU reduces engine speed and then slips the two clutch packs at the same time to maintain a reduced turbine speed for a torque converter. In another aspect of the transmission system, energy loss is reduced during high draw bar pull conditions. The engine speed is modulated to trim energy peaks at low pushing or pulling speeds. An additional transmission gear reduction restores the lost pushing or pulling forces while generating less heat in the torque converter.

Abstract: In a toroidal continuously variable transmission (TCVT) control apparatus with a variator unit and a ratio control hydraulic system, an electronic TCVT control unit electronically feedback-controls a transmission ratio based on a deviation from a desired transmission ratio, and generates a normal-period command signal to be input to a step motor for compensating for the deviation. The control unit determines whether the deviation can be compensated for by electronically feedback-controlling the transmission ratio based on the deviation and generates an abnormal-period command signal to be input to the step motor to realize a step-motor displacement capable of shifting or diverging the transmission ratio to a speed-reduction side, while keeping a trunnion out of contact with a stopper in the direction of the trunnion axis, when the deviation cannot be compensated for by electronically feedback-controlling the transmission ratio based on the deviation.

Abstract: A bicycle shift control device includes a shift signal output unit for outputting shift signals and an inhibiting unit operatively coupled to the shift signal output unit for inhibiting the output of a second shift signal after the output of a first shift signal. In a more specific embodiment, the inhibiting unit inhibits the output of the second shift signal for a predetermined standby time after the output of the first shift signal.

Abstract: A method and system of automatically controlling engine speed of a vehicle in a turn employs an engine control system (10) to determine an optimal engine speed for the turn and an actual engine speed as sensed by an engine speed sensor (38). Engine control system (10) determines the difference between optimal engine speed and actual engine speed and compares this difference to current engine load. Based on this comparison, engine control system (10) then determines whether to alter engine speed and, if so, determines an amount to reduce the difference between optimal engine speed and actual engine speed.

Abstract: A vehicle speed control system for a vehicle with an engine and an automatic transmission is comprised of a coast switch for decreasing a set vehicle speed and a controller connected with the coast switch. The controller controls a vehicle speed at the set vehicle speed by controlling the engine and the automatic transmission, and maintains a gear ratio of the automatic transmission at the gear ratio set at the moment before decreasing the set vehicle speed when the coast switch is being operated to decrease the set vehicle speed. Therefore, even if the throttle opening is opened to accelerate the vehicle, the engine rotation speed is never radically increased under such a transmission condition. This prevents the engine from generating noises excessively.

Abstract: In a vehicle with a gear-shift transmission of a kind that requires a torque-free state to shift gears, the riding comfort is improved by a method of shifting gears where a gear shift is preceded by the steps of: reducing the vehicle acceleration at a time t1 from an existing level (1) to a first acceleration level (3), maintaining the vehicle acceleration at the reduced level (3) for a predetermined time interval, and at the end point t3 of the predetermined time interval, reducing the acceleration further to a second acceleration level that is lower than the first level.

Abstract: An objective method is provided for selecting gear ratios for use in a motor vehicle transmission having multiple selectable gears. The method includes selecting gear ratios for a specific application includes calculating a low gear ratio, and a high gear ratio based upon vehicle parameters and performance requirements. The total ratio spread is determined by dividing the low gear ratio by the high gear ratio. Using the total ratio spread, a geometric sequence is created with a plurality of terms, such that each of the terms respectively represent the ratio steps between the gears. Lastly, each gear ratio is divided by its respective ratio step plus one to find the gear ratio for the next gear. This method provides an objective method for selecting gear ratios, such that the steps between each of the ratios are uniformly progressive.

Abstract: A shift control system for a toroidal CVT employs a shift technique for setting a torque shift compensation quantity so as to be increased as an actual gear ratio approaches a low-speed side gear ratio region including a lowest-speed gear ratio and so as to be decreased when the actual gear ratio is in the low-speed side gear ratio region. Further, the shift control system is arranged to select a gear ratio in a low-speed side gear ratio region after a gear ratio in a high-speed side gear ratio region is selected.

Abstract: A transmission system includes a Central Processing Unit (CPU) that controls truck braking energy by sharing energy dissipation between clutch packs. The CPU reduces engine speed and then slips the two clutch packs at the same time to maintain a reduced turbine speed for a torque converter. In another aspect of the transmission system, energy loss is reduced during high draw bar pull conditions. The engine speed is modulated to trim energy peaks at low pushing or pulling speeds. An additional transmission gear reduction restores the lost pushing or pulling forces while generating less heat in the torque converter.

Abstract: A vehicle speed control system is installed to a vehicle equipped with an engine and a continuously variable transmission (CVT). The vehicle control system is comprised of a controller arranged to execute a vehicle speed control, to suspend the vehicle speed control when a throttle opening is increased to be greater than a target throttle opening for the vehicle speed control and to restart the suspended vehicle speed control when the throttle opening becomes smaller than the target throttle opening. Further, the controller is arranged to decrease the throttle opening and to execute a shift down of the CVT when the vehicle speed at the moment of restarting the vehicle speed control is greater than or equal to the target vehicle speed. Therefore, this vehicle speed control system can quickly and smoothly decelerate the vehicle without generating shift shocks when the vehicle speed control is restarted.

Abstract: A transmission system includes a Central Processing Unit (CPU) that controls truck braking energy by sharing energy dissipation between clutch packs. The CPU reduces engine speed and then slips the two clutch packs at the same time to maintain a reduced turbine speed for a torque converter. In another aspect of the transmission system, energy loss is reduced during high draw bar pull conditions. The engine speed is modulated to trim energy peaks at low pushing or pulling speeds. An additional transmission gear reduction restores the lost pushing or pulling forces while generating less heat in the torque converter.

Abstract: A transmission system includes a Central Processing Unit (CPU) that controls truck braking energy by sharing energy dissipation between clutch packs. The CPU reduces engine speed and then slips the two clutch packs at the same time to maintain a reduced turbine speed for a torque converter. In another aspect of the transmission system, energy loss is reduced during high draw bar pull conditions. The engine speed is modulated to trim energy peaks at low pushing or pulling speeds. An additional transmission gear reduction restores the lost pushing or pulling forces while generating less heat in the torque converter.

Abstract: A method and a device for setting a gear ratio of the transmission while a distance and/or vehicle-speed control system (ACC system) is activated. A setpoint variable, as a function of which at least the driving motor of the vehicle is controlled, is input. The setpoint variable or a value derived from this setpoint variable is limited in response to the existence of a first operating state, and the gear ratio is then set as a function of the limited variable, or as a function of the limited value. The gear ratio is set as a function of the setpoint variable, or as a function of the value, in response to the existence of a second operating state. The method and device prevent unnecessary and uncomfortable occurrences of downshifting during ACC operation, without losing the option of accelerating sharply.

Abstract: A system for controlling an automated mechanical change-gear transmission system including a processing unit for processing inputs according to predetermined logic rules to determine currently engaged and allowably engaged gear ratios and throttle positions, for changing between automatic and semi-automatic transmission modes, for issuing command output signals to non-manually controlled operators, and for temporarily selectively overriding a pre-selected transmission mode if either cruise control or power take off are activated.

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: A method for controlling a powertrain of a vehicle is described. The method determines a desired vehicle condition based on three driver actuated elements. In a preferred embodiment the first element can be pedal position, the second element can be a brake actuator or, more specifically, brake actuation duration, and the third element can be a gear selection lever. Further, the desired vehicle condition can be desired powertrain output, vehicle acceleration, or various other parameters.

Abstract: A vehicle speed control system for a vehicle with an engine and an automatic transmission is comprised of a coast switch for decreasing a set vehicle speed and a controller connected with the coast switch. The controller controls a vehicle speed at the set vehicle speed by controlling the engine and the automatic transmission, and maintains a gear ratio of the automatic transmission at the gear ratio set at the moment before decreasing the set vehicle speed when the coast switch is being operated to decrease the set vehicle speed. Therefore, even if the throttle opening is opened to accelerate the vehicle, the engine rotation speed is never radically increased under such a transmission condition. This prevents the engine from generating noises excessively.

Abstract: The gearshift of an automatic transmission (25) connected to an engine is controlled by a transmission controller (15) in response to the vehicle speed and the accelerator pedal depression amount. The controller (11) calculates a transmission target automatic transmission output torque so that the vehicle speed coincides with a predetermined vehicle speed (17), and calculates the output torque of the engine based on the gear ratio and the transmission target output torque (27). The controller (11) determines whether or not the transmission target output torque is in a state in which a predetermined increase is not possible (21). When the transmission target output torque is in the state in which a predetermined increase is not possible, the controller (11) limits the transmission target automatic transmission output torque (17, 17B) and controls the output torque of the engine based on the limited transmission target output torque (19A, 20, 21).

Abstract: In automatic vehicular velocity controlling apparatus and method for automotive vehicle, a target vehicular velocity to maintain a predetermined inter-vehicle distance between a preceding vehicle which is running ahead of the vehicle is set as a first set vehicular velocity and a vehicular velocity of the vehicle (host vehicle) is controlled to give one of the first set vehicular velocity and a second set vehicular velocity by a manual setting through a set switch and an accelerate switch or coast switch if the preceding vehicle is present and is controlled to maintain the vehicular velocity at the second set vehicular velocity if no preceding vehicle is present. Then, when the set vehicular velocity is modified through the above-described accelerate switch or coast switch, a vehicular velocity variation rate is determined in accordance with a deviation between the actual vehicular velocity and a newly set vehicular velocity after the modification of the vehicular occupant's vehicular velocity.