Vehicle control unit

Abstract

Vehicle control unit, with: a sensor (22) configured to detect a physical quantity of a turning movement which varies depending on a state of a turning movement of a vehicle when the vehicle turns; an acceleration / deceleration device (40, 46, 50, 54) which is configured to vary the acceleration / deceleration of the vehicle; a control unit (20) which is configured to perform acceleration / deceleration control in order to: to determine whether the vehicle is traveling on a curved road or not by determining whether the physical magnitude of a turning movement satisfies a predetermined control start condition or not (steps 600 to 695); if it is determined that the vehicle is traveling on a curved road (step 540: Yes), calculate a required acceleration / deceleration to maintain the vehicle at a target speed depending on the curvature of the curved road, and control the acceleration / deceleration device to make the actual acceleration / deceleration of the vehicle equal to the calculated required acceleration / deceleration; and a shape acquisition device (23, 27, 28, 29) which is configured to acquire road shape information which represents a shape of a road at a position which is a predetermined distance away from the vehicle along a direction of movement of the vehicle, where the control unit (20) is configured as follows: Determine whether a curved road exists in the direction of travel of the vehicle or not, based on the road shape information (step 615); Determine that a first control start condition is satisfied as the control start condition (step 625) if the magnitude of the physical quantity of a turning motion has changed from a value less than a first value to a value equal to or greater than the first value (step 630: Yes), in a case where it is determined that the curved road is not present (step 615: No); and Determine that a second control start condition is satisfied as the control start condition (step 625) if a quantity of the physical quantity of a turning motion has changed from a value that is less than a second value that is less than the first value to a value that is equal to or greater than the second value (step 620: Yes), in a case where it is determined that the curved road is present (step 615: Yes), where the control unit (20) is configured as follows: Starting an initial acceleration / deceleration control as an acceleration / deceleration control (step 550) when it is determined that the initial control start condition is met (step 1025: Yes); Starting a second acceleration / deceleration control as an acceleration / deceleration control (step 1020) if it is determined that the second control start condition is met (step 1015: Yes); and Calculating the required acceleration / deceleration in such a way that the required acceleration / deceleration value for the second acceleration / deceleration control is smaller than the required acceleration / deceleration value for the first acceleration / deceleration control. where the control unit (20) is set up when it is determined that the first control start condition is met, while the second acceleration / deceleration control is executed to start the first acceleration / deceleration control, to calculate the required acceleration / deceleration in such a way that the magnitude of a change in the required acceleration / deceleration per unit of time does not exceed a predetermined safeguard threshold (step 1420 to step 1435), in a time span from a start time at which the first acceleration / deceleration control is started to an end time at which a predetermined time has elapsed since the start time (step 1405: Yes).

Description

Technical field

[0001] The present disclosure relates to a vehicle control device configured to perform acceleration / deceleration control for controlling acceleration and deceleration (i.e., acceleration / deceleration) of the vehicle in order to enable the vehicle to travel / run at an appropriate speed on a curved road (or in a curved lane). background

[0002] A vehicle control device is known that is configured to perform acceleration / deceleration control (sometimes referred to as speed management control or SPM control) for controlling the acceleration / deceleration of the vehicle when the vehicle is traveling on a curved road. For example, a vehicle control device (hereinafter referred to as the "conventional device") shown in Japanese Patent Publication JP 2015-67 270 A, as the SPM control, performs G-vector control as well as anticipatory G-vector control. The G-vector control is a control for managing the acceleration / deceleration of the vehicle using a "lateral acceleration" of the vehicle (acting upon it), which is detected by a sensor.The predictive G-vector control is a system for controlling the acceleration / deceleration of a vehicle based on a vehicle speed Vpv, a current vehicle speed V, and a road curvature Kpv. The vehicle speed Vpv is the speed of the vehicle when it is at a predictive position / point located a distance Lpv away from the vehicle's current position in a forward direction. The road curvature Kpv is the road curvature at the predictive position.

[0003] The road curvature Kpv (i.e., the road curvature at the looking-ahead position) begins to increase before the vehicle begins to change its direction of travel / travel as the vehicle approaches the curved road (i.e., before a driver begins to operate / turn a steering wheel).

[0004] In light of the above, the conventional device performs anticipatory G-vector control to manage the vehicle's acceleration / deceleration before the vehicle begins to change its direction of travel.

[0005] The conventional device obtains the road curvature Kpv (i.e., the road curvature at the foresight position) based on map data. Therefore, it is necessary for the conventional device to acquire / derive the vehicle's current position based on GPS signals or similar. If the current position cannot be acquired with high accuracy, the road curvature Kpv will deviate significantly from the true value. Additionally, if the vehicle is in an area where it cannot receive GPS signals, the road curvature Kpv cannot be obtained. Consequently, if the map data does not include updated data to reflect a new road curvature, the road curvature Kpv can also deviate significantly from the true value.

[0006] For the reasons stated above, the acceleration / deceleration controlled by the predictive G-vector control described above may deviate from an ideal acceleration / deceleration that is obtained / determined based on the (true) road curvature of the road on which the vehicle is actually traveling. This can cause the driver discomfort. Therefore, consideration may be given to configuring the device to perform only G-vector control, without performing predictive G-vector control.

[0007] The G-vector control activates when lateral acceleration actually begins to occur (or act on the vehicle). Therefore, for example, if the vehicle changes lanes between straight lanes, the G-vector control may be activated, regardless of whether the vehicle is actually driving on the curved road. To prevent the G-vector control from activating in such a case, the device may be configured to activate it when the lateral acceleration is equal to or greater than a "lateral acceleration threshold set at a comparatively high value." However, if the lateral acceleration threshold is set at the high value, the activation time of the G-vector control is delayed, thus allowing the driver to apply the brake pedal while driving on the curved road.The driver who pressed the brake pedal in the above case may have doubts about the reliability of the SPM control system.

[0008] US 2011 / 0 178 689 A1 discloses a vehicle control device comprising a front wheel steering angle sensor for detecting the steering angle of the front wheels, a steering wheel angle sensor for detecting the rotation angle of the steering wheel, wheel speed sensors, and other sensors such as a yaw rate sensor, acceleration sensors, an internal combustion engine speed sensor, etc., a brake actuator for individually adjusting the brake pressures in the wheels, and a system for acquiring the actual rotational state. If the vehicle tends to understeer, a deceleration control system is enabled to output a deceleration control setpoint. An execution evaluation system decides whether to execute the deceleration control.

[0009] EP 2 712 780 A1 discloses a vehicle control device adapted to determine that a first control start condition is met when the magnitude of the physical quantity of a turning movement has changed from a value less than a first value to a value equal to or greater than the first value, in a case where it is determined that the curved road is not present; and to determine that a second control start condition is met when the magnitude of the physical quantity of a turning movement has changed from a value less than a second value, which is less than the first value, to a value equal to or greater than the second value, in a case where it is determined that the curved road is present. Summary

[0010] The present invention was developed to solve the problems described above. The object of the present disclosure is to provide a vehicle control device capable of reducing the possibility of the acceleration / deceleration control being wrongly activated when the vehicle is not traveling on the curved road, and increasing the probability that the acceleration / deceleration control will be activated at an early time when the vehicle is traveling on the curved road.

[0011] This problem is solved by a vehicle control device having the features of claim 1.

[0012] The control unit is configured as follows: Determine whether a curved road exists in the direction of travel of the vehicle or not, based on the road shape information (step 615); Determine that a first control start condition is satisfied as the control start condition (step 625) if a quantity of the physical quantity of a turning motion has changed from a value less than a first value to a value equal to or greater than the first value (step 630: Yes), in a case where it is determined that the curved road is not present (step 615: No); and Determine that a second control start condition is satisfied as the control start condition (Step 625) if the magnitude of the physical quantity of a turning motion has changed from a value that is less than a second value that is less than the first value to a value that is equal to or greater than the second value (Step 620: Yes), in a case where it is determined that the curved road is present (Step 615: Yes).In this way, the device disclosed herein, as configured in this manner, changes the control start condition to a condition that can be more easily satisfied (by the physical quantity of a turning motion, such as the yaw rate or a lateral acceleration) when it is determined that the curved road exists, based on the road shape information at the position (or the foresight position) that is a predetermined distance away from the vehicle along the direction of travel of the vehicle, compared with (or in contrast to the case) when it is not determined that the curved road exists.Accordingly, the device disclosed herein can reduce the probability that the acceleration / deceleration control will be started incorrectly when the vehicle is traveling on a straight road, and can increase the probability that the acceleration / deceleration control will be started at the earlier time when the vehicle is traveling on the curved road.

[0013] In some embodiments of the present disclosure, the control unit is configured as follows: Starting an initial acceleration / deceleration control as the acceleration / deceleration control (step 550, which is in Fig. 10 is shown), if it is determined that the first control start condition is met (step 1025: Yes); Starting a second acceleration / deceleration control as the acceleration / deceleration control (step 1020) when it is determined that the second control start condition is met (step 1015: Yes); and Calculating the required acceleration / deceleration in such a way that the required acceleration / deceleration value for the second acceleration / deceleration control is smaller than the required acceleration / deceleration value for the first acceleration / deceleration control ( Fig. 11).

[0014] The second control start condition, which is easier to fulfill than the first, is met earlier, so the execution of the second acceleration / deceleration control is initiated first. Therefore, even if the acceleration / deceleration control is incorrectly initiated when the vehicle is not traveling on the curved road, the second acceleration / deceleration control will still be executed. Additionally, the magnitude of the acceleration / deceleration required for the second acceleration / deceleration control, for a given vehicle speed and curvature, is smaller than the magnitude required for the first acceleration / deceleration control for that same vehicle speed and curvature. Consequently, any unfamiliar sensation experienced by the driver can be suppressed / reduced, even if the acceleration / deceleration control (i.e.,, the second acceleration / deceleration control) is wrongly started to be executed.

[0015] In the present disclosure, the control unit is set up when it is determined that the first control start condition is met, while the second acceleration / deceleration control is executed to start the first acceleration / deceleration control, to calculate the required acceleration / deceleration in such a way that the magnitude of a change in the required acceleration / deceleration per unit of time does not exceed a predetermined safeguard threshold (steps 1420 to 1435), in a time span from a start time at which the first acceleration / deceleration control is started to an end time at which a predetermined time has elapsed from the start time (step 1405: Yes).

[0016] According to the configuration described above, the amount of change in the required acceleration / deceleration per unit of time does not exceed the protection threshold when and after the first acceleration / deceleration control is initiated, while the second acceleration / deceleration control is being executed. Therefore, any unusual sensation or discomfort that the driver may experience can be suppressed / reduced.

[0017] An alternative vehicle control device is shown in claim 2.

[0018] This vehicle control device of the present disclosure has a steering angle change device (60, 66) which is configured to change a steering angle of the vehicle, and wherein the control unit is configured to: Performing steering angle control to calculate a target steering angle to guide the vehicle along a lane, and controlling the steering angle change device to make an actual steering angle of the vehicle equal to the target steering angle; Determine whether a magnitude of the target steering angle is equal to or greater than a predetermined threshold angle, or not (step 905), when it is determined that the curved road is present, based on the road shape information; Acceleration / deceleration control begins when the second control start condition is met (step 620, which is in Fig. 9 is shown: Yes), while the magnitude of the target steering angle is equal to or greater than the threshold angle (step 905: Yes); and Determine that a third control start condition is satisfied as the control start condition (Step 910: Yes) if a quantity of the physical quantity of a turning motion has changed from a value less than a third value to a value equal to or greater than the third value, while the quantity of the target steering angle is less than the threshold angle (Step 905: No), where the third value is less than the first value and greater than the second value.

[0019] According to the above configuration, the probability of the acceleration / deceleration control being incorrectly activated when the vehicle is traveling on a straight road can be reduced. Additionally, the probability of the acceleration / deceleration control being activated earlier when the vehicle is traveling on a curved road can be increased.

[0020] It should be noted that, in order to facilitate understanding of the present disclosure, in the foregoing description, the individual elements or the like of the disclosure corresponding to those of the embodiments of the disclosure described below are accompanied by names and / or symbols in parentheses that are used in the embodiments. However, the individual elements of the disclosure are not limited to those in the embodiments defined by the names and / or symbols. Other problems, other features, and related advantages of the present disclosure will be readily apparent from the subsequent description of embodiments of the disclosure, which is made with reference to the accompanying drawings. Brief description of the drawings Fig. Figure 1 is a schematic diagram of a vehicle control device (a first control device) according to a first embodiment of the present disclosure. Fig. Figure 2 is a top view of a section that includes a curved road. Fig. Figure 3 is a drawing to describe the curvature of the curved road, the yaw rate, the lateral acceleration, and the lateral jerk observed when a vehicle travels on the curved road. Fig. Figure 4 is a drawing to describe a start condition of a speed management controller (SPM controller). Fig. 5 is a flowchart executed by a CPU of a driver assistance ECU located in Fig. 1 is shown. Fig. Figure 6 is a flowchart showing a subroutine executed by the CPU for an SPM start condition fulfillment determination in the routine that is in Fig. 5 is shown. Fig. 7 A flowchart showing a subroutine executed by the CPU for an SPM end-condition fulfillment determination in the routine that is in Fig. 5 is shown. Fig. Figure 8 is a flowchart showing a subroutine executed by the CPU to calculate a required acceleration / deceleration within the routine that is in Fig. 5 is shown. Fig. Figure 9 is a flowchart showing a subroutine executed by a CPU according to a modification of the first embodiment for an SPM start condition fulfillment determination. Fig. Figure 10 is a flowchart executed by a CPU of a driver assistance ECU according to a second embodiment of the present disclosure. Fig. Figure 11 is a drawing to describe an amplification characteristic map of the second embodiment. Fig. Figure 12 is a flowchart showing a subroutine executed by the CPU for a second SPM start condition fulfillment determination in the routine that is in Fig. 10 is shown. Fig. Figure 13 is a flowchart showing a subroutine executed by the CPU for an initial SPM start condition fulfillment determination in the routine that is in Fig. 10 is shown. Fig. Figure 14 is a flowchart showing a routine executed by a CPU according to a modification of the second embodiment. Detailed description (First embodiment)

[0021] A vehicle control device (hereinafter referred to as the “first device”) 10 according to a first embodiment of the present disclosure is described with reference to Fig. 1 to 8 described. Fig. Figure 1 shows the first device 10 and a vehicle VA in which the first device 10 is used.

[0022] As in Fig. As shown in Figure 1, the first device 10 has a drive support ECU (hereinafter referred to as "DSECU") 20, a power unit ECU 40, a brake ECU 50, and a steering ECU 60. These ECUs are interconnected to exchange data via a CAN (control unit network).

[0023] ECU stands for Electronic Control Unit. Each ECU is an electronic control unit that includes a microcomputer as its main component. The microcomputer comprises a CPU, ROM, RAM, and an interface. The CPU is configured or programmed to perform various functions by executing instructions, programs, or routines stored in memory, which is the ROM. Some or all of the ECUs 20, 40, 50, and 60 can be integrated into a single ECU.

[0024] The first device 10 further comprises a multitude of wheel speed sensors 21, a yaw rate sensor 22, a camera device 23, a millimeter-wave radar device 24, an acceleration sensor 25, an ACC (adaptive cruise control) switch 26, and a navigation system 27. They are connected to the DSECU 20.

[0025] The wheel speed sensors 21 are located on the corresponding wheels of the vehicle VA. Each wheel speed sensor 21 generates a wheel pulse signal when the corresponding wheel rotates through a predetermined angle. The DSECU 20 counts the number of wheel pulse signals from each wheel speed sensor 21 per unit of time and obtains a wheel rotation speed (or wheel RPM) for each wheel based on the count. The DSECU 20 obtains a vehicle speed VS, which indicates the speed of movement of the vehicle VA based on the wheel RPMs. For example, the DSECU 20 obtains the average wheel RPM of four of the wheels as the vehicle speed Vs.

[0026] The yaw rate sensor 22 detects a magnitude of yaw rate acting on the vehicle VA in order to output / generate a signal that indicates a yaw rate Yr based on the detected magnitude of the yaw rate.

[0027] The camera device 23 is mounted on the upper part of a windshield and in the cabin of the vehicle VA. The camera device 23 is configured to acquire image data of a scene / area in front of (in the area in front of) the vehicle VA. Based on the image data, the camera device 23 is configured to acquire object information, including the distance between the object and the vehicle VA, the object's direction relative to the vehicle VA, and information regarding a white line (lane marking) that delimits a lane in which the vehicle VA is traveling / walking.

[0028] The millimeter-wave radar device 24 is located at the front end of the vehicle and near its midpoint in a width direction. The millimeter-wave radar device 24 emits a millimeter wave that propagates in a predetermined area in front of the vehicle. The millimeter wave is reflected by an object, such as another vehicle, a pedestrian, a motorcycle, or a bicycle. The millimeter-wave radar device 24 receives the reflected wave and obtains object information based on it. The object information obtained by the millimeter-wave radar device 24 includes the distance between the object and the vehicle VA, the relative velocity of the object with respect to the vehicle VA, and the direction of the object with respect to the vehicle VA.

[0029] It should be noted that the DSECU 20 corrects the object information obtained by the millimeter wave radar device 24 based on the object information obtained by the camera device 23 in order to obtain a final object information that is used for an ACC (adaptive speed control) which is described below.

[0030] The acceleration sensor 25 is configured to detect a front / rear directional acceleration Gx and a lateral acceleration Gy and transmits signals to the DSECU 20, which display these accelerations. The front / rear directional acceleration Gx is the acceleration of the vehicle VA in a longitudinal direction (front / rear direction). The lateral acceleration Gy is the acceleration of the vehicle VA in a transverse direction (width direction).

[0031] The ACC switch 26 is a switch operated by the driver to toggle the ACC's execution state between an execution-enabled state and an execution-impedited / prevented state. The execution-enabled state is a state in which the ACC can be executed, and the execution-impedited state is a state in which the ACC cannot be executed (or is prevented). If the driver operates the ACC switch 26 while the ACC's execution state is in the execution-impedited state, the DSECU 20 changes the execution state to the execution-enabled state. Conversely, if the driver operates the ACC switch 26 while the ACC's execution state is in the execution-enabled state, the DSECU 20 changes the execution state to the execution-impedited state.

[0032] Additionally, the ACC switch 26 is operated by the driver to set / change set parameters used for the ACC, which include a set target vehicle speed Vset, as described below, and a target distance Dtgt between vehicles, as described below.

[0033] The navigation system 27 includes a GPS receiver 28. The GPS receiver 28 receives GPS signals from a multitude of GPS satellites and determines / obtains a current position (on the Earth's surface) of the vehicle VA based on the received GPS signals. The GPS receiver 28 transmits position signals / data, indicating an accurate current position of the vehicle VA, to the DSECU 20. The navigation system 27 has map data 29 (has map data 29 pre-stored) that includes information about "a position on the Earth's surface, a road curvature, and the like" for each curved road.

[0034] The power engine ECU 40 is connected to an accelerator pedal actuation circumference sensor 42 and a power engine sensor 44 and receives detection signals from these sensors 42, 44.

[0035] The accelerator pedal actuation range sensor 42 is configured to detect an actuation range (that is, an accelerator pedal actuation range AP) of an unseen accelerator pedal of the vehicle VA. When the driver does not actuate (release) the accelerator pedal, the accelerator pedal actuation range AP is "0".

[0036] The engine sensor 44 is designed to detect operating parameters of a gasoline-injected, spark-ignition internal combustion engine (not shown) that serves as a drive source for vehicle VA. The engine sensor 44 may include a throttle valve opening sensor, an engine speed sensor, and an intake air volume sensor.

[0037] The engine control unit (ECU) 40 is further connected to an engine actuator 46, which can be a throttle valve actuator or fuel injectors. The engine control unit (ECU) 40 is configured to drive the engine actuator 46 to modify the torque generated by the internal combustion engine in order to adjust the driving force of the vehicle VA.

[0038] The engine control unit (ECU) 40 determines a target throttle valve opening (TAtgt) such that the target throttle valve opening (TAtgt) increases as the accelerator pedal actuation range (AP) increases. The engine control unit (ECU) 40 drives the throttle valve actuator to make the throttle valve opening equal to the target throttle valve opening (TAtgt).

[0039] The brake ECU 50 is connected to the wheel speed sensors 21 and a brake pedal actuation circumference sensor 52 and receives detected signals from them.

[0040] The brake pedal actuation range sensor 52 is configured to detect the actuation range (i.e., the brake pedal actuation range BP) of a brake pedal not shown on the vehicle VA. When the driver does not actuate (release) the brake pedal, the brake pedal actuation range BP is "0".

[0041] The brake ECU 50 is configured to obtain each of the wheel speeds and the vehicle speed Vs based on the wheel pulse signals from each of the wheel speed sensors 21, similar to the DSECU 20. The brake ECU 50 can be configured to receive the wheel speeds and vehicle speed Vs from the DSECU 20.

[0042] The brake ECU 50 is further connected to a brake actuator 54, which is a hydraulically controlled actuator. The brake actuator 54 is arranged in a hydraulic circuit (not shown) between a master cylinder for pressurizing hydraulic oil in accordance with a brake pedal force and friction brake devices, which include known wheel cylinders provided at the wheels. The brake actuator 54 can adjust / change the pressure of the hydraulic oil supplied to the wheel cylinders in order to adjust / control a braking force of the vehicle VA.

[0043] The brake ECU 50 determines a target acceleration / deceleration, which is now negative, based on the brake pedal actuation range BP. The brake ECU 50 drives the brake actuator 54 to achieve an actual acceleration of the vehicle VA equal to the target acceleration / deceleration.

[0044] The steering ECU 60 is a control unit for a known electric power steering system and is connected to a steering angle sensor 62 and a steering motor 66. The steering motor 66 is embedded in a steering mechanism (not shown) of the vehicle VA, comprising a steering wheel, a steering shaft connected to the steering wheel, and a steering gear mechanism.

[0045] The steering angle sensor 62 is configured to detect a steering angle Θ of the vehicle VA in order to transmit the detected signal indicating the steering angle Θ to the steering ECU 60.

[0046] The steering motor 66 generates torque using electrical energy controlled by the steering ECU 60. The direction, magnitude, and other parameters of the torque are set by the steering ECU 60. This torque is used to generate power steering torque and / or to steer a left-hand and a right-hand drive wheel. Thus, the steering ECU 60 is configured to control / change the steering angle Θ using the steering motor 66. The electrical energy is supplied to the steering motor 66 from a vehicle battery (not shown) mounted on the vehicle VA. <acc>

[0047] The DSECU 20 is configured to perform / execute the ACC as described below when the ACC execution state is the execution-enabled state.

[0048] If there is no vehicle ahead, which is another vehicle in front of vehicle VA, the DSECU 20 calculates / determines a required acceleration / deceleration Gxacc of the ACC to make vehicle VA travel / run at the predetermined target vehicle speed Vset described above, and performs control of a constant speed based on the required acceleration / deceleration Gxacc.

[0049] If, however, the vehicle ahead is present, the DSECU 20 calculates / determines a required acceleration / deceleration Gxacc of the ACC to make the vehicle VA drive / run in such a way that a distance between the vehicle ahead and the vehicle VA becomes equal to the target distance Dtgt between vehicles described above, and performs a tracking control based on the required acceleration / deceleration Gxacc.

[0050] It should be noted that the DSECU 20 is set up to determine whether the vehicle ahead is present or not, based on the object information obtained by the millimeter wave radar device 24 and / or the object information obtained by the camera device 23.

[0051] While the DSECU 20 performs the ACC, it transmits the required acceleration / deceleration Gxacc of the ACC to the power unit ECU 40 and the brake ECU 50 for either constant speed control or coasting control as a target acceleration / deceleration Gtgt. This can make the actual acceleration of the vehicle VA equal to the target acceleration / deceleration Gtgt without requiring the driver to use the accelerator and brake pedals. It is important to note that the acceleration / deceleration indicates either acceleration or deceleration, depending on its sign (+ or -). Specifically, if the sign of the acceleration / deceleration is positive (plus) in this description, the acceleration / deceleration means acceleration.If the sign of the acceleration / deceleration is negative (minus), the acceleration / deceleration represents a deceleration. Furthermore, if the acceleration is large in the given description, the absolute value of the acceleration (or the absolute value of the acceleration / deceleration that is positive) is large. If the acceleration is small, the absolute value of the acceleration (or the absolute value of the acceleration / deceleration that is positive) is small. If the deceleration is large, the absolute value of the deceleration (or the absolute value of the acceleration / deceleration that is negative) is large. If the deceleration is small, the absolute value of the deceleration (or the absolute value of the acceleration / deceleration that is negative) is small. <spm-steuerung>

[0052] The brake ECU 20 is configured to perform speed management control (sometimes referred to below as "SPM control" or "acceleration / deceleration control") when an SPM start condition is met as the vehicle VA enters a curved road while ACC is active. SPM control is a control mechanism for managing the acceleration / deceleration of the vehicle VA so that the vehicle VA travels / travels at an appropriate vehicle speed for the curved road.

[0053] The DSECU 20 calculates (determines by calculation) the required acceleration / deceleration Gxacc for ACC and a required acceleration / deceleration Gxspm for SPM control simultaneously and selects a target acceleration / deceleration Gxtgt, the required acceleration / deceleration Gxacc, or the required acceleration / deceleration Gxspm, whichever is lower. The DSECU 20 then controls the actual acceleration / deceleration of the vehicle VA using the target acceleration / deceleration Gxtgt (in such a way that the actual acceleration / deceleration of the vehicle VA matches the target acceleration / deceleration Gxtgt).

[0054] It should be noted that if SPM control is not required, the DSECU 20 sets the required acceleration / deceleration Gxspm for SPM control to a value close to positive infinity. Therefore, the required acceleration / deceleration Gxspm for SPM is not selected as the target acceleration / deceleration Gxtgt (in other words, the actual acceleration / deceleration of the vehicle VA is controlled based on the required acceleration / deceleration Gxacc for ACC). The value close to positive infinity described above can be referred to as an "invalid acceleration / deceleration Gxinv".

[0055] Fig. Figure 3 shows “the yaw rate Yr, the lateral acceleration Gy and a lateral jerk Jy, which is a derivative value (dGy / dt) of the lateral acceleration Gy with respect to time”, acting on the vehicle VA when the vehicle VA travels at a constant speed on “a first straight road RST1, a curved road RCU and then a second straight road RST2”, which is in Fig. The two sections shown in this order drive / run. Note that the curved road RCU consists of a first clothoid curve section RCL1, a uniformly circular section RSC, and a second clothoid curve section RCL2, as shown in Fig. 2 is shown.

[0056] As in Fig. As shown in Figure 3, a curvature C (the inverse of a radius of curvature) gradually increases from zero in the first clothoid curve section RCL1, becomes constant in the uniformly circular section RSC, and then gradually decreases to zero in the second clothoid curve section RCL2. The curvature C represents the sharpness / tightness of the curved road RCU. As the curvature C decreases, the curved road RCU becomes less sharp. As the curvature C increases, the curved road RCU becomes more sharp.

[0057] When vehicle VA enters the first clothoid curve RCL1 from the first straight section RST1, the driver of vehicle VA begins to actuate the steering wheel (i.e., begins to turn the steering wheel). As a result, the yaw rate Yr and the lateral acceleration Gy gradually increase. The lateral jerk Jy immediately rises (increases) to a certain positive constant value at the moment the lateral acceleration Gy begins to increase and then remains at that positive constant value. When and after vehicle VA enters the uniformly circular section RSC from the first clothoid curve RCL1, the lateral acceleration Gy remains at a constant value. The lateral jerk Jy becomes zero at the moment vehicle VA enters the uniformly circular section RSC from the first clothoid curve RCL1 and remains zero while the vehicle is traveling / running in the uniformly circular section RSC.When and after the vehicle VA enters the second clothoid curve section RCL2 from the uniformly circular section RSC, the lateral acceleration Gy gradually decreases. The lateral jerk Jy immediately changes to a specific negative constant value at the moment the lateral acceleration Gy begins to decrease and then remains at that negative constant value.

[0058] When the vehicle VA enters the first clothoid curve section RCL1 and the yaw rate Yr thus increases, the SPM start condition (control start condition) described below is met. When the SPM start condition is met, the DSECU 20 begins to calculate the required acceleration / deceleration Gxspm for the SPM control.

[0059] More precisely, while vehicle VA is traveling through the first clothoid curve section RCL1, the DSECU 20 calculates the required acceleration / deceleration Gxspm to decelerate vehicle VA (that is, Gxspm < 0). While vehicle VA is traveling through the uniformly circular section RSC, the DSECU 20 calculates the required acceleration / deceleration Gxspm to maintain vehicle VA at a constant speed. While vehicle VA is traveling through the second clothoid curve section RCL2, the DSECU 20 calculates the required acceleration / deceleration Gxspm to accelerate vehicle VA (that is, Gxspm > 0). (Overview of a company)

[0060] An overview of the operation of the first device 10 will follow, with reference to Fig. 4 described.

[0061] The DSECU 20 derives (calculates, extrapolates) a derived curvature Cp, a curvature C (that is, a magnitude of curvature C) of its own lane at a forward position Pp, which is a distance Ld away from the current position of the vehicle VA in a forward direction (that is, a direction of movement / travel of the vehicle VA). The own lane is a lane in which the vehicle VA is currently traveling. The DSECU 20 determines whether the derived curvature Cp is equal to or greater than a predetermined curvature threshold Cpth.

[0062] If it is determined that the derived curvature Cp is less than the curvature threshold Cpth, the DSECU 20 determines that the SPM start condition is met when the yaw rate Yr is equal to or greater than a first yaw rate threshold Yr1th. It should be noted that the derived curvature Cp, which is determined at a position P2, is in Fig. 4 is shown, is obtained, equal to or greater than the curvature threshold Cpth, where for the purposes of description it is assumed that the derived curvature Cp is less than the curvature threshold Cpth.

[0063] If, however, it is determined that the derived curvature Cp is equal to or greater than the curvature threshold Cpth, the DSECU 20 determines that the SPM start condition is met when the yaw rate Yr becomes equal to or greater than a second yaw rate threshold Yr2th (see point P1, which is in Fig. (as shown in Figure 4). The second yaw rate threshold, Yr2th, was defined as a value smaller than the first yaw rate threshold, Yr1th. In some cases, the first yaw rate threshold, Yr1th, is referred to as the "first value," and the second yaw rate threshold, Yr2th, is referred to as the "second value."

[0064] This means that if the derived curvature Cp becomes equal to or greater than the curvature threshold Cpth, it is likely that the curved road RCU is present in front of the vehicle VA. Given this, the SPM start condition was set to a condition that is more easily satisfied (by the yaw rate Yr in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth) compared to the case where the derived curvature Cp is less than the curvature threshold Cpth. It is worth noting that the SPM start condition for the case where the derived curvature Cp is less than the curvature threshold Cpth (that is, the condition that the yaw rate Yr is equal to or greater than the first yaw rate threshold Yr1th) can be referred to as a "normal start condition" or a "first control start condition".Furthermore, the SPM start condition for the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth (that is, the condition that the yaw rate Yr is equal to or greater than the second yaw rate threshold Yr2th) can be referred to as a “start condition of a case where a curved road is present” or a “second control start condition”.

[0065] The first device 10 set up in this way can reduce the probability that the SPM control will be started incorrectly when the vehicle VA is not traveling on the curved road, and can increase the probability that the SPM control will be started at a suitable early time when the vehicle VA is traveling on the curved road. (Exact operation)

[0066] The CPU of the DSECU 20 is configured or programmed to run a routine (SPM control routine) that is in Fig. As shown in Figure 5, this is to be executed every time a predetermined time elapses. Hereinafter, CPU refers to the CPU of the DSECU 20, unless otherwise specified.

[0067] When a suitable time arrives, the CPU initiates a dismantling control from step 500 and executes the process of step 505 to step 535 in that order, and then proceeds to step 540.

[0068] Step 505: The CPU obtains the yaw rate Yr by receiving the signal from the yaw rate sensor 22 and obtains the vehicle speed Vs based on the wheel pulse signals from the wheel speed sensors 21.

[0069] Step 510: The CPU obtains (calculates) an actual curvature Ca, which is a curvature C (of the road) at the current / present position of the vehicle Va, the lateral acceleration Gy, and the lateral jerk Jy.

[0070] More precisely, the CPU obtains the actual curvature Ca by using the lateral acceleration Gy and the vehicle speed Vs in an equation (1) described below. Ca=Yr / Vs

[0071] The CPU obtains the actual lateral acceleration Gy by using the yaw rate Yr and the vehicle speed Vs in equation (2), which is described below. Gy=Yr⋅Vs

[0072] The CPU obtains the lateral jerk Jy by using a currently calculated Gy(n) and a previously calculated Gy(n-1) in equation (3) as described below. The previously calculated Gy(n-1) is a calculated Gy that was computed at a predetermined time (or one computation cycle prior to the current time). Jy=Gy(n)−Gy(n−1)

[0073] Step 515: The CPU obtains the camera image (i.e., image data) obtained by the camera device 23.

[0074] Step 520: The CPU determines / detects a pair of lane markings (that is, a left white line and a right white line) that define the lane (recording lane) in which the vehicle VA is currently driving, from (based on) the acquired image data.

[0075] Step 525: The CPU obtains as the derived curvature Cp a curvature C of a virtual line at the foresight position Pp, where the virtual line passes through a midpoint of the pair of lane markings that delimit the receiving lane in the road width direction.

[0076] Step 530: The CPU executes a determination routine for whether an SPM start condition is met, which is described in detail below. The determination routine for whether an SPM start condition is met is a routine for determining whether the SPM start condition is met or not.

[0077] Step 535: The CPU executes a determination routine for whether an SPM end condition has been met, which is described below. The determination routine for whether an SPM end condition has been met is a routine for determining whether the SPM end condition has been met or not.

[0078] Step 540: The CPU determines whether the value of an SPM control flag Xspm is "1" or not. The value of the SPM control flag Xspm is set to "1" when the SPM start condition is met (see step 625, described below) and is set to "0" when the SPM end condition is met (see step 715, described below). Note that the value of the SPM control flag Xspm is set to "0" by an unseen initialization routine executed by the CPU when the position of an unseen ignition key switch changes from an off position to an on position.

[0079] If the value of the SPM control flag Xspm is "0", the CPU makes a "no" determination at step 540 to proceed to step 545. At step 545, the CPU sets the required acceleration / deceleration Gxspm to the invalid acceleration / deceleration Gxinv and transmits the required acceleration / deceleration Gxspm to the power engine ECU 40 and the brake ECU 50. The CPU then proceeds to step 595 to temporarily terminate the current routine.

[0080] Conversely, if the value of the SPM control flag Xspm is "1" at the time the CPU proceeds to step 540, the CPU makes a "yes" determination at step 540 and executes the processes of steps 550 and 555 in that order. Afterward, the CPU proceeds to step 595 to temporarily terminate the current routine.

[0081] Step 550: The CPU performs a calculation routine for a required acceleration / deceleration, described below, to calculate the required acceleration / deceleration Gxspm.

[0082] Step 555: The CPU transmits the required acceleration / deceleration Gxspm to the power engine ECU 40 and the brake ECU 50. <SPM-Startbedingungserfüllungsbestimmung>

[0083] When the CPU proceeds to step 530, which is in Fig. As shown in Figure 5, the CPU begins a flow control process from step 600 of the determination routine for the fulfillment of an SPM start condition, which is shown in a flowchart in Fig. 6 is shown, and proceeds to step 605. In step 605, the CPU determines whether the value of the SPM control flag Xspm is "0" or not.

[0084] If the value of the SPM control flag Xspm is "0", the CPU makes a "yes" determination at step 605 and proceeds to step 610. At step 610, the CPU determines whether the execution state of the ACC is the execution-allowed state or not. If the execution state of the ACC is the execution-allowed state, the CPU makes a "yes" determination at step 610 and proceeds to step 615.

[0085] In step 615, the CPU determines whether the derived curvature Cp is equal to or greater than the curvature threshold Cpth. If the derived curvature Cp is equal to or greater than the curvature threshold Cpth, the CPU makes a "yes" determination in step 615 and proceeds to step 620. In step 620, the CPU determines whether the yaw rate Yr is equal to or greater than the second yaw rate threshold Yr2th.

[0086] If the yaw rate Yr is less than the second yaw rate threshold Yr2th, the CPU makes a "no" determination at step 620 and proceeds to step 695 to temporarily terminate the current routine. Conversely, if the yaw rate Yr is equal to or greater than the second yaw rate threshold Yr2th, the CPU makes a "yes" determination at step 620 and proceeds to step 625 to set the value of the SPM control flag Xspm to "1". The CPU then proceeds to step 695 to temporarily terminate the current routine.In this way, the CPU determines that the control start condition (second control start condition) is met in order to set the SPM control flag Xspm to "1" when the yaw rate Yr changes from a value less than the second yaw rate threshold Yr2th to a value equal to or greater than the second yaw rate threshold Yr2th, in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth.

[0087] If, meanwhile, the derived curvature Cp is less than the curvature threshold Cpth at the time the CPU proceeds to step 615, the CPU makes a "no" determination at step 615 and proceeds to step 630. At step 630, the CPU determines whether the yaw rate Yr is equal to or greater than "the first yaw rate threshold Yr1th, which is greater than the second yaw rate threshold Yr2th" or not.

[0088] If the yaw rate Yr is less than the first yaw rate threshold Yr1th, the CPU makes a "no" determination at step 630 and proceeds to step 695 to temporarily terminate the current routine. Conversely, if the yaw rate Yr has changed from a value less than the first yaw rate threshold Yr1th to a value equal to or greater than the first yaw rate threshold Yr1th, the CPU makes a "yes" determination at step 630 and proceeds to step 625 to set the value of the SPM control flag Xspm to "1".In this way, the CPU determines that the control start condition (first control start condition) is met in order to set the SPM control flag Xspm to "1" when the yaw rate Yr has changed from a value less than the first yaw rate threshold Yr1th to a value equal to or greater than the first yaw rate threshold Yr1th, in the case where the derived curvature Cp is less than the curvature threshold Cpth.

[0089] However, if the execution state of the ACC is not in the execution-enabled state at the time the CPU proceeds to step 610, the CPU makes a "no" determination at step 610 and proceeds to step 695 to temporarily terminate the current routine.

[0090] Furthermore, the CPU makes a "no" determination at step 610 if the value of the SPM control flag Xspm is "1". If the CPU proceeds to step 605, the CPU makes a "no" determination at step 605 and proceeds to step 695 to temporarily terminate the current routine. <SPM-Endbedingungserfüllungsbestimmung>

[0091] When the CPU proceeds to step 535, which is in Fig. As shown in Figure 5, the CPU begins a flow control process from step 700 of the determination routine for the fulfillment of an SPM end condition, which is defined by a flowchart in Figure 5. Fig. 7 is shown, and proceeds to step 705. In step 705, the CPU determines whether the value of the SPM control flag Xspm is "1" or not.

[0092] If the value of the SPM control flag Xspm is "1", the CPU makes a "yes" determination at step 705 and proceeds to step 710. At step 710, the CPU determines whether the execution state of the ACC is in the invalid state. If the execution state of the ACC is in the invalid state, the CPU makes a "yes" determination at step 710 and proceeds to step 715. At step 715, the CPU sets the value of the SPM control flag Xspm to "0" and proceeds to step 795 to temporarily terminate the current routine.

[0093] If, however, the execution state of ACC is not in the execution invalid state, the CPU makes a "no" determination at step 710 and proceeds to step 720. At step 720, the CPU determines whether the actual curvature Ca is equal to or less than an actual curvature threshold Cath. The actual curvature threshold Cath has been set to a value (close to zero) that is less than the curvature threshold Cpth.

[0094] If the actual curvature Ca is equal to or less than the actual curvature threshold Cath, the CPU makes a "yes" determination at step 720 and proceeds to step 715 to set the value of the SPM control flag Xspm to "0". Conversely, if the actual curvature Ca is greater than the actual curvature threshold Cath, the CPU makes a "no" determination at step 720 and proceeds to step 795 to temporarily terminate the current routine.

[0095] However, if the value of the SPM control flag Xspm is “0” at the time the CPU proceeds to step 705, the CPU makes a “no” determination at step 705 and proceeds to step 795 to temporarily terminate the current routine. <Berechnung einer erforderlichen Beschleunigung / Verzögerung>

[0096] When the CPU proceeds to step 550, which is in Fig. As shown in Figure 5, the CPU begins a flow control process from step 800 of a calculation routine for a required acceleration / deceleration, which is represented by a flowchart in Figure 5. Fig. As shown in Figure 8, the process continues to step 805. At step 805, the CPU determines whether the product (Gy - Jy) of the lateral acceleration Gy and the lateral jerk Jy is equal to or greater than zero. If the product (Gy - Jy) is equal to or greater than zero, the CPU proceeds to steps from / off step 810 to decelerate the vehicle VA. Conversely, if the product (Gy - Jy) is negative, the CPU proceeds to step 835 to accelerate the vehicle VA.

[0097] As in Fig. Figure 3 shows that when and after the vehicle enters the first clothoid curve RCL1 from the first straight section RST1, the magnitude of the lateral acceleration Gy increases from zero. At this point, the sign of the lateral jerk Jy is the same as the sign of the lateral acceleration Gy. Therefore, the product (Gy · Jy) is positive. When and after the vehicle VA enters the uniformly circular section RSC from the first clothoid curve RCL1, the lateral acceleration Gy remains constant. At this point, the lateral jerk Jy is zero. Therefore, the product (Gy - Jy) is zero. When and after the vehicle VA enters the second clothoid curve RCL2 from the uniformly circular section RSC, the magnitude of the lateral acceleration Gy decreases. At this point, the sign of the lateral jerk Jy is opposite to the sign of the lateral acceleration Gy. Therefore, the product (Gy - Jy) is negative.

[0098] If the product (Gy - Jy) is equal to or greater than zero, that is, if the vehicle VA is in either the first clothoid curve section RCL1 or the uniformly circular section RSC, the CPU makes a "yes" determination at step 805 and executes the processes from step 810 to step 830 in that order. Afterward, the CPU proceeds to step 895 to temporarily terminate the current routine.

[0099] Step 810: The CPU obtains a base acceleration / deceleration Gxb by multiplying an absolute value of the lateral jerk Jy by "-1". Typically, the base acceleration / deceleration Gxb is negative, and thus represents a deceleration. However, when the vehicle VA is in the uniformly circular section RSC, the base acceleration / deceleration Gxb is zero because the value of the lateral jerk Jy is zero. In this case, as described below, the required acceleration / deceleration Gxspm is zero. Accordingly, the value of the required acceleration / deceleration Gxspm is zero while the vehicle VA is traveling in the uniformly circular section RSC.

[0100] Step 815: The CPU obtains a target vehicle speed Vtgt by using the actual curvature Ca in a target vehicle speed map MapVtgt(C). The target vehicle speed map MapVtgt(C) is a lookup table that defines a relationship between the curvature C and the target vehicle speed Vtgt such that the target vehicle speed Vtgt decreases as the curvature C increases (i.e., as the curved road becomes more sharply curved). The target vehicle speed map MapVtgt(C) was pre-stored in the ROM of the DSECU 20.

[0101] Step 820: The CPU obtains a vehicle speed difference ΔV (=Vtgt - Vs) by subtracting the current vehicle speed Vs from the target vehicle speed Vtgt.

[0102] Step 825: The CPU obtains a gain Ga by using the vehicle speed difference ΔV with a gain map MapGa(ΔV). The gain map MapGa(ΔV) is a lookup table that defines a relationship between the vehicle speed difference ΔV and the gain Ga, and was pre-stored in the ROM of the DSECU 20. According to the gain map MapGa(ΔV), a value of Ga is equal to "1" when the vehicle speed difference ΔV is negative (i.e., Vtgt < 0). According to the gain map MapGa(ΔV), the value of Ga decreases from "1" to "0" when the vehicle speed difference ΔV increases, while the vehicle speed difference ΔV is positive (i.e., Vtgt > 0).

[0103] Step 830: The CPU achieves the required acceleration / deceleration Gxspm by multiplying the base acceleration / deceleration Gxb by the gain Ga.

[0104] If, however, the product (Gy - Jy) is negative (namely, if the vehicle VA is in the second clothoid curve section RCL2), at the time the CPU proceeds to step 805, the CPU makes a "no" determination at step 805 and proceeds to step 835. At step 835, the CPU obtains the absolute value of the lateral jerk Jy as the required acceleration / deceleration Gxspm. The CPU then proceeds to step 895 to temporarily terminate the current routine.

[0105] As described above, for the first device 10, the SPM start condition is the condition that is met when the yaw rate Yr is equal to or greater than the second yaw rate threshold Yr2th in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth, whereas the SPM start condition is the condition that is met when the yaw rate Yr is equal to or greater than the first yaw rate threshold Yr1th, which is greater than the second yaw rate threshold Yr2th, in the case where the derived curvature Cp is less than the curvature threshold Cpth. In other words, the first device 10 changes the SPM start condition to a condition that is easier to satisfy when the derived curvature Cp is equal to or greater than the curvature threshold Cpth than when the derived curvature Cp is less than the curvature threshold Cpth.Therefore, the first device 10 can reduce the probability that the SPM start condition is wrongly determined to be met when the vehicle VA is not traveling on the curved road RCU, and can allow the SPM start condition to be met at the appropriate early time when the vehicle VA is traveling on the curved road RCU. (Modification of the first embodiment)

[0106] The DSECU 20 according to this modification of the first embodiment implements a lane tracking support control (referred to as an “LTA”). The lane tracking support control is a control (steering control) to obtain, by calculation, a target steering angle ΘLTA to ensure that the position of the vehicle VA in the lane width direction corresponds to a “target driving line Ltgt defined in the receiving lane,” and to drive the steering motor 66 to vary a steering angle to make the steering angle Θ correspond to the target steering angle ΘLTA. The target driving line Ltgt is, for example, the virtual line that passes through the midpoint of the pair of right and left lane markings that delimit the receiving lane in the road width direction.

[0107] For example, the DSECU 20 obtains the target steering angle ΘLTA in accordance with the equation (4) below. ΘLTA=K1⋅Cb+K2⋅ΘL+K3⋅dL

[0108] In equation (4), Cb is an actual curvature of the target path Ltgt (that is, a curvature of the target path Ltgt at the current position of the vehicle VA). A sign (+ or -) of the curvature Cb, which is taken into account when the target path Ltgt is a left curve, is opposite to a sign of the curvature Cb, which is taken into account when the target path Ltgt is a right curve.

[0109] ΘL is a deviation angle (difference of an angle) between a direction of the target travel line Ltgt and a direction of movement of the vehicle VA.

[0110] dL is a distance in the lane width direction between the target driving line Ltgt and a center position of a front end of the vehicle VA in the vehicle width direction.

[0111] The values ​​(Cb, ΘL, dL) can be obtained by the camera device 23, or can be obtained by the DSECU 20 based on the camera image obtained by the camera device 23.

[0112] K1, K2 and K3 are reinforcements (constants).

[0113] It should be noted that the lane following support control is known (see, for example, Japanese patent publication JP 2008 - 195 402 A, Japanese patent publication JP 2009 - 190 464 A, Japanese patent publication JP 2010 - 6 279 A and Japanese patent JP 4 349 210 B2).

[0114] Meanwhile, as can be seen from equation (4) described above for calculating the target steering angle ΘLTA, the target steering angle ΘLTA is a value that varies depending on the actual curvature Cb of the road on which the vehicle VA is traveling at its current position. Therefore, the absolute value |ΘLTA| of the target steering angle ΘLTA tends to increase when and after the vehicle enters the first clothoid curve RCL1 from the first straight road RST1. In other words, if the absolute value |ΘLTA| is large, it is likely, or can be taken into account, that the vehicle VA has already entered the curved road RCU.

[0115] In light of the foregoing, in the present modification, in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth, the SPM start condition used when the magnitude (absolute value |ΘLTA|) of the target steering angle ΘLTA is equal to or greater than a threshold angle Θth, has been set to a condition that is more easily satisfied (by the yaw rate Yr) than (or compared with) the SPM start condition used when the magnitude of the target steering angle ΘLTA is less than the threshold angle Θth.

[0116] The CPU of the present modification differs from the CPU of the first device 10 of the embodiment described above only in that it includes a determination routine for the fulfillment of an SPM start condition, which is described in Fig. 9 is shown, instead of performing the routine shown in Fig. Figure 6 is shown. It should be noted that each of the steps shown in Fig. Figure 9 shows the CPU performing the same process as the corresponding steps shown in Fig. 6 are shown, execute, using the same reference symbol as the one given that is in Fig. The 6 steps shown are given, and their description can be omitted.

[0117] When the CPU proceeds to step 530, which is in Fig. As shown in Figure 5, the CPU begins a flow control from step 900 of a subroutine, which is represented by a flowchart in Figure 5. Fig. 9 is shown. If the CPU makes a "yes" determination at each of the "steps 605, 610 and 615", which are shown in Fig. As shown in Figure 9, the CPU proceeds to step 905. In step 905, the CPU determines whether the magnitude (absolute value |ΘLTA|) of the target steering angle ΘLTA is equal to or greater than the threshold angle Θth.

[0118] If the magnitude (|ΘLTA|) of the target steering angle ΘLTA is equal to or greater than the threshold Θth, the CPU makes a "yes" determination at step 905 and proceeds to step 620, which is in Fig. Figure 9 shows how to determine whether the yaw rate Yr is equal to or greater than the second yaw rate threshold Yr2th described above. If, however, the magnitude (|ΘLTA|) of the target steering angle ΘLTA is less than the threshold angle Θth, the CPU makes a "no" determination at step 905 and proceeds to step 910.

[0119] In step 910, the CPU determines whether the yaw rate Yr is equal to or greater than a third yaw rate threshold Yr3th. The third yaw rate threshold Yr3th was set to a value greater than the second yaw rate threshold Yr2th and less than the first yaw rate threshold Yr1th. The third yaw rate threshold Yr3th can be referred to as a "third value".

[0120] If the yaw rate Yr is less than the third yaw rate threshold Yr3th, it can be determined that the SPM start condition has not been met. In this case, the CPU makes a "no" determination at step 910 and proceeds to step 995 to temporarily terminate the current routine. Conversely, if the yaw rate Yr is equal to or greater than the third yaw rate threshold Yr3th, it can be determined that the SPM start condition has been met. In this case, the CPU makes a "yes" determination at step 910 and proceeds to step 625, which is in Fig. 9 is shown.

[0121] In this way, if the derived curvature Cp is equal to or greater than the curvature threshold Cpth and the magnitude (|ΘLTA|) of the target steering angle ΘLTA is equal to or greater than the threshold angle Θth, it is determined that the control start condition (second control start condition) is met, and the value of the SPM control flag Xspm is set to "1" when the yaw rate Yr changes from a value less than the second yaw rate threshold Yr2th to a value equal to or greater than the second yaw rate threshold Yr2th.

[0122] Additionally, in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth and the magnitude (|ΘLTA|) of the target steering angle ΘLTA is less than the threshold angle Θth, it is determined that the control start condition (second control start condition) is satisfied, and the value of the SPM control flag Xspm is set to "1" when the yaw rate Yr has changed from a value less than the third yaw rate threshold Yr3th to a value equal to or greater than the third yaw rate threshold Yr3th.

[0123] The modification set up in this way can reduce the probability that the SPM start condition will be wrongly determined to be met when the vehicle VA is not traveling on the curved road RCU, and can allow the SPM start condition to be met at the appropriate early time when the vehicle VA is traveling on the curved road RCU. (Second embodiment)

[0124] A vehicle control device (hereinafter referred to as the “second device”) 10 according to a second embodiment of the present disclosure is described with reference to Fig. Described in sections 10 to 13.

[0125] The second device 10 obtains the required acceleration / deceleration Gxspm, a first required acceleration / deceleration Gxspm1, by calculation when a first SPM start condition (first control start condition) is met. The first SPM start condition is met when the yaw rate Yr becomes equal to or greater than the first yaw rate threshold Yr1th.

[0126] The second device 10 achieves a second required acceleration / deceleration Gxspm2 by calculation when a second SPM start condition is met. The second SPM start condition is met when the yaw rate Yr becomes equal to or greater than the second yaw rate threshold Yr2th, which is less than the first yaw rate threshold Yr1th, while (in that case) the derived curvature Cp is equal to or greater than the curvature threshold Cpth.

[0127] Furthermore, the second device 10 obtains the first required acceleration / deceleration Gxspm1 and the second required acceleration / deceleration Gxspm2 by calculation in such a way that one magnitude of the second required acceleration / deceleration Gxspm2 is smaller than one magnitude of the first required acceleration / deceleration Gxspm1.

[0128] The CPU of the DSECU 20 of the second device 10 executes a routine that is described by a flowchart in Fig. 10 is shown, instead of the routine that is in Fig. 5 is shown. It should be noted that each of the steps shown in Fig. 10 are shown, which use the same process on the CPU as the corresponding ones in Fig. Perform the 5 steps shown, using the same reference symbol as the one that is in Fig. The 5 steps shown are given, and their description can be omitted.

[0129] Below, a first SPM control flag X1spm can simply be referred to as flag X1spm, and a second SPM control flag X2spm can simply be referred to as flag X2spm.

[0130] When a suitable time arrives, the CPU begins a sequence control of step 1000, which in Fig. As shown in Figure 10, the CPU executes the processes from step 505 to step 525, and then proceeds to step 1005 and step 1010. At step 1005, the CPU executes a "determination routine for whether a second SPM start condition has been met," which is described below. At step 1010, the CPU executes a "determination routine for whether a first SPM start condition has been met," which is described below. Afterward, the CPU executes the process from step 535 and proceeds to step 1015.

[0131] In step 1015, the CPU determines whether the value of the X2spm flag is "1" or not. The value of the X2spm flag is set to "1" when the second SPM start condition is met (see step 1210, described below), and is set to "0" when the first SPM start condition is met (see step 1310, described below). Additionally, the value of the X2spm flag is set to "0" by the initialization routine described above, and is also set to "0" when the SPM end condition is met.

[0132] If the value of the X2spm flag is "1", the CPU makes a "yes" determination at step 1015 and proceeds to step 1020. At step 1020, the CPU executes a calculation routine for a derived required acceleration / deceleration in order to calculate the second required acceleration / deceleration, Gxspm2.

[0133] The calculation routine for a derived required acceleration / deceleration is almost the same as the calculation routine for a required acceleration / deceleration determined by the flowchart in Fig. Figure 8 is shown, except for the following points. Specifically, when the CPU proceeds to step 825 in the calculation routine for a derived required acceleration / deceleration, the CPU obtains a Ga' gain by using the vehicle speed difference ΔV with a gain map MapGa'(ΔV), which is defined by a solid line in Fig. Figure 11 shows that the gain Ga' obtained using the gain map MapGa'(ΔV) is half the gain Ga obtained using the gain map MapGa(ΔV) shown in Fig. 8 is shown (the gain characteristic map MapGa(ΔV) is in Fig. (11 shown by a dashed line). Thus, if the vehicle speed difference ΔV is a specific value, the gain Ga', used in the calculation routine for a derived required acceleration / deceleration, is smaller than the gain Ga. Similarly, if the lateral jerk Jy and the vehicle speed difference ΔV are corresponding specific values, the magnitude of the second required acceleration / deceleration Gxspm2 is smaller than the magnitude of the first required acceleration / deceleration Gxspm1.

[0134] Then, at step 555, which is in Fig. 10 shows the required acceleration / deceleration Gxspm and proceeds to step 1095 to provisionally terminate the present routine.

[0135] If, however, the value of the X2spm flag is "0" at the time the CPU proceeds to step 1015, the CPU makes a "no" determination at step 1015 and proceeds to step 1025. At step 1025, the CPU determines whether the value of the X1spm flag is "1" or not. The value of the X1spm flag is set to "1" when the first SPM start condition is met (see step 1310, described below) and is set to "0" when the SPM end condition is met. Additionally, the value of the X1spm flag is set to "0" by the initialization routine described above.

[0136] If the value of the X1spm flag is "1", the CPU makes a "yes" determination at step 1025 and proceeds to step 550, which is in Fig. 10 is shown. At step 550, the CPU executes the calculation routine for a required acceleration / deceleration, which is shown in Fig. Figure 8 shows how to calculate the required acceleration / deceleration Gxspm as the first required acceleration / deceleration Gxspm1. In this case, the gain characteristic map MapGa(ΔV) is used, which is found in block B82 in Fig. Figure 8 is shown. The CPU then proceeds to step 555, which is shown in Fig. 10 is shown.

[0137] If, however, the value of the X1spm flag is "0", the CPU makes a "no" determination at step 1025 and proceeds to step 545, which is in Fig. 10 is shown. <Zweite SPM-Startbedingungserfüllungsbestimmung>

[0138] When the CPU proceeds to step 1005, which is in Fig. As shown in 10, the CPU begins a flow control of step 1200 of the second SPM start condition fulfillment determination routine, which is shown in a flowchart in Fig. 12 is shown, and proceeds to step 1205. It should be noted that each of the steps shown in Fig. 12 are shown, which use the same process on the CPU as the corresponding ones in Fig. Perform the 6 steps shown, using the same reference symbol as the one given that is in Fig. The 6 steps shown are given, and their description can be omitted.

[0139] At step 1205, the CPU determines whether both the value of flag X1spm and flag X2spm are "0" or not. If both the value of flag X1spm and flag X2spm are "0", the CPU makes a "yes" determination at step 1205 and proceeds to step 610, which is in Fig. 12 is shown. If the CPU makes a "yes" determination at step 610, which is shown in Fig. As shown in step 12, the CPU proceeds to step 615, which is in Fig. 12 is shown.

[0140] If the CPU makes a "no" determination at step 615, which is in Fig. As shown in 12, the CPU runs, unlike the routine shown in Fig. As shown in Figure 6, proceed directly to step 1295 to provisionally terminate the present routine without proceeding to step 630.

[0141] If the CPU makes a "yes" determination at step 615, which is in Fig. As shown in step 12, the CPU proceeds to step 620, which is in Fig. 12 is shown. If the CPU makes a "yes" determination at step 620, which is shown in Fig. As shown in step 12, the CPU proceeds to step 1210 to set the value of the X2spm flag to "1". Afterward, the CPU proceeds to step 1295 to temporarily terminate the current routine.

[0142] However, if at least one of the values ​​of flag X1spm and flag X2spm is "1" at the time the CPU proceeds to step 1205, the CPU makes a "no" determination at step 1205 and proceeds to step 1295 to temporarily terminate the current routine. Furthermore, if the CPU makes a "no" determination at either step 610 or step 620, the CPU proceeds to step 1295 to temporarily terminate the current routine. <Erste SPM-Startbedingungserfüllungsbestimmung>

[0143] When the CPU proceeds to step 1010, which is in Fig. As shown in 10, the CPU begins a flow control of step 1300 of the first SPM start condition fulfillment determination routine, which is represented by a flowchart in Fig. 13 is shown, and proceeds to step 1305. It should be noted that each of the steps shown in Fig. 13 are shown, which use the same process on the CPU as the corresponding ones in Fig. The 6 steps shown are executed, using the same reference symbol as the one given to the one in Fig. The step shown in step 6 is given, and its description can be omitted.

[0144] At step 1305, the CPU determines whether the value of the X1spm flag is "0" or not. If the value of the X1spm flag is "0", the CPU makes a "yes" determination at step 1305 to proceed to step 610, which is in Fig. 13 is shown. If the CPU makes a "yes" determination at step 610, which is shown in Fig. As shown in step 13, the CPU proceeds to step 630, which is in Fig. 13 is shown.

[0145] If the CPU makes a "yes" determination at step 630, which is in Fig. As shown in Figure 13, the CPU proceeds to step 1310 to set the value of the X1spm flag to "1" and the value of the X2spm flag to "0". Afterward, the CPU proceeds to step 1395 to temporarily terminate the current routine.

[0146] It should be noted that the CPU will proceed directly to step 1395 to temporarily terminate the current routine if the CPU receives a "no" determination at any of the steps in step 610. Fig. 13 is shown, and takes step 630, which is in Fig. 13 is shown, makes.

[0147] As described above, the second device 10, set up in this way, calculates the first required acceleration / deceleration Gxspm1 and the second required acceleration / deceleration Gxspm2 in such a way that the magnitude of the second required acceleration / deceleration Gxspm2 is smaller than the magnitude of the first required acceleration / deceleration Gxspm1. Accordingly, even if it is incorrectly determined that the second SPM start condition has been met while the vehicle is traveling on the straight road, the magnitude of the required acceleration / deceleration Gxspm (that is, the magnitude of the second required acceleration / deceleration Gxspm2) is relatively small, and thus any unusual sensation that the driver might experience can be suppressed. (Variation of the second embodiment)

[0148] The modification of the second embodiment will be described next with reference to Fig. 14 described. As described above, the magnitude of the second required acceleration / deceleration Gxspm2 is smaller than the magnitude of the first required acceleration / deceleration Gxspm1. Thus, when the yaw rate Yr becomes larger than the relatively large first yaw rate threshold Yr1th, such that the first SPM start condition is met, after the yaw rate Yr has become larger than the relatively small second yaw rate threshold Yr2th, such that the second SPM start condition is met, in the case where the derived curvature Cp is equal to or greater than the curvature threshold Cpth, the required acceleration / deceleration Gxspm changes rapidly from the second required acceleration / deceleration Gxspm2 to the first required acceleration / deceleration Gxspm1. In other words, the rate of change in the required acceleration / deceleration Gxspm per unit time becomes large in the case described above.In light of the foregoing, the CPU of this modification imposes a limit on the required acceleration / deceleration Gxspm such that the magnitude of the change in the required acceleration / deceleration Gxspm per unit of time does not exceed a threshold (protection value) Gth when the first SPM start condition is met after the second SPM start condition has been met. This can reduce the likelihood of a driver experiencing a feeling of unease immediately after the first SPM start condition is met.

[0149] If the CPU of the present modification makes a "yes" determination at step 630, which is in Fig. As shown in step 13, the CPU sets the value of a timer T to "0" if the value of the Xspm2 flag is "1", through steps not shown, and then proceeds to step 1310, which is shown in Fig. 13 is shown. However, if the CPU of the present modification makes a "yes" determination at step 630, which is shown in Fig. As shown in Figure 13, when the value of the Xspm2 flag is "0", the CPU sets the value of the timer T to a "predetermined value greater than a timer threshold Tth, described below", through steps not shown, and then proceeds to step 1310, which is shown in Fig. 13 is shown.

[0150] After the CPU of the present modification has completed the process of step 550, which is in Fig. As shown in step 10, the CPU proceeds to step 1405, which is in Fig. Figure 14 shows that the CPU determines whether the value of the timer T is equal to or less than the timer threshold Tth. If the value of the timer T is equal to or less than the timer threshold Tth, the CPU makes a "yes" determination at step 1405 and executes the processes of step 1410 and step 1415 in that order to proceed to step 1420.

[0151] At step 1410, the CPU adds "1" to the value of the timer T.

[0152] At step 1415, the CPU calculates an acceleration / deceleration difference ΔGxspm, which is the change in the required acceleration / deceleration Gxspm per unit of time, by subtracting a previous required acceleration / deceleration Gxspm (n-1) from a current required acceleration / deceleration Gxspm (n). The current required acceleration / deceleration Gxspm (n) is the required acceleration / deceleration Gxspm that was currently obtained at step 550, which is in Fig. Figure 10 shows the earlier required acceleration / deceleration Gxspm (n-1) as the required acceleration / deceleration Gxspm that was previously (a predetermined time before) achieved at "either step 1020 or step 550", as shown in Fig. 10 are shown.

[0153] At step 1420, the CPU determines whether the acceleration / deceleration difference ΔGxspm is greater than the threshold Gth, which is a positive value.

[0154] If the magnitude of the acceleration / deceleration difference ΔGxspm is greater than the threshold Gth, the CPU makes a "yes" determination at step 1420 to proceed to step 1425. At step 1425, the CPU determines whether the acceleration / deceleration difference ΔGxspm is less than zero. If the acceleration / deceleration difference ΔGxspm is less than zero (that is, if the current required acceleration / deceleration Gxspm(n) is less than the previous required acceleration / deceleration Gxspm(n-1)), the CPU makes a "yes" determination at step 1425 and proceeds to step 1430.

[0155] At step 1430, the CPU uses a subtracted value as the current required acceleration / deceleration Gxspm (n). This subtracted value is obtained by subtracting the threshold Gth from the previous required acceleration / deceleration Gxspm (n-1). The CPU then proceeds to step 555, which is in Fig. Figure 10 shows that these processes can prevent the amount of change (the size of the) during the required acceleration / deceleration Gxspm from exceeding the threshold Gth.

[0156] If, however, the acceleration / deceleration difference ΔGxspm is greater than zero, the CPU makes a "no" determination at step 1425 to proceed to step 1435. At step 1435, the CPU uses as the current required acceleration / deceleration Gxspm(n) an added value obtained by adding the threshold Gth to the previous required acceleration / deceleration Gxspm(n-1). The CPU then proceeds to step 555, which is in Fig. Figure 10 shows that these processes can also prevent the amount of change (the magnitude of) during the required acceleration / deceleration Gxspm from exceeding the threshold Gth.

[0157] It should be noted that if the value of the timer T is greater than the timer threshold Tth, the CPU makes a "no" determination at step 1405 in order to proceed directly to step 555, which is in Fig. 10 is shown. Furthermore, if the magnitude of the acceleration / deceleration difference ΔGxspm is equal to or less than the threshold Gth, the CPU makes a "no" determination at step 1420 in order to proceed directly to step 555, which is shown in Fig. 10 is shown.

[0158] As described above, over a period from a first specified time (start time), described below, to a second specified time (end time), described below (that is, the period during which the timer value T is equal to or greater than zero and equal to or less than the timer threshold Tth), after the first SPM start condition is met, after the second SPM start condition is met, the required acceleration / deceleration Gxspm is calculated (obtained) in such a way that the magnitude of the change in the required acceleration / deceleration Gxspm per unit time does not exceed the threshold Gth. The first specified time is the time at which the first SPM start condition is met. The second specified time is the time at which a predetermined amount of time has elapsed since the time at which the first SPM start condition is met.This can reduce the likelihood of the driver experiencing a feeling of strangeness, where the feeling of strangeness is caused by a rapid change in acceleration / deceleration Gx acting on the vehicle VA.

[0159] The present disclosure should not be limited to the foregoing embodiments and may include various modifications within the scope of the present disclosure.

[0160] For example, the CPU may be configured to operate as described below when the derived curvature Cp is equal to or greater than the curvature threshold Cpth.

[0161] The CPU converts / modifies the actual yaw rate Yr, detected by the yaw rate sensor 22, into a yaw rate value YrL that is greater than but equal to the actual yaw rate Yr. For example, the yaw rate value YrL can be obtained by multiplying the actual yaw rate Yr by a coefficient greater than 1. The CPU then determines whether the converted yaw rate value YrL is equal to or greater than a predetermined yaw rate threshold Yrth to determine whether the second SPM start condition is met.If, in this configuration, the derived curvature Cp is less than the curvature threshold Cpth, the CPU does not perform the conversion described above on the actual yaw rate Yr detected by yaw rate sensor 22. Instead, it determines whether the actual yaw rate Yr detected by yaw rate sensor 22 is equal to or greater than the yaw rate threshold Yrth to determine whether the first SPM start condition is met. This modification can also change the SPM start condition used when the derived curvature Cp is equal to or greater than the curvature threshold Cpth to one that is more easily met when the derived curvature Cp is less than the curvature threshold Cpth.

[0162] Furthermore, the CPU can be configured to determine whether the SPM start condition is met or not using a magnitude of the lateral acceleration Gy instead of the yaw rate Yr. In other words, a physical parameter, such as the yaw rate Yr and the lateral acceleration Gy, used to determine whether the SPM start condition is met or not, can be a physical quantity (referred to as the "physical quantity of a turning motion") that acts on the vehicle VA during a turning motion of the vehicle VA (that is, any of the physical quantities that varies in response to the turning motion of the vehicle VA).

[0163] Additionally, the CPU can obtain a current position of the vehicle VA based on signals obtained by the GPS receiver 28, and as the derived curvature Cp, obtains the curvature C at the predicted position Pp using the map data 29 and the current position obtained in this way.

[0164] The vehicle control units described above can also be used in electric and hybrid vehicles. Furthermore, the method for calculating the required acceleration / deceleration Gxspm should not be limited to the methods described above.

[0165] The vehicle control unit includes a sensor for detecting a physical quantity of a turning motion, an acceleration / deceleration device, a control unit, and a device for acquiring road shape information, which represents the shape of a road at a predetermined distance from the vehicle. The unit determines that a first control start condition is met when a quantity of the physical quantity exceeds a certain initial value, while the curved road is determined to be non-existent. Based on the road shape information, the unit then performs acceleration / deceleration control to cause the vehicle to travel at a target speed depending on the curvature of the road.The unit determines that a second control start condition is met when the magnitude of the physical quantity exceeds a second value that is smaller than the first value, while the curved road has been determined to be present in order to perform the acceleration / deceleration control. < / acc>

Claims

[1] Vehicle control unit, with: a sensor (22) configured to detect a physical quantity of a turning movement which varies depending on a state of a turning movement of a vehicle when the vehicle turns; an acceleration / deceleration device (40, 46, 50, 54) which is configured to vary the acceleration / deceleration of the vehicle; a control unit (20) which is configured to perform acceleration / deceleration control in order to: to determine whether the vehicle is traveling on a curved road or not by determining whether the physical magnitude of a turning movement satisfies a predetermined control start condition or not (steps 600 to 695); if it is determined that the vehicle is traveling on a curved road (step 540: Yes), calculate a required acceleration / deceleration to maintain the vehicle at a target speed depending on the curvature of the curved road, and control the acceleration / deceleration device to make the actual acceleration / deceleration of the vehicle equal to the calculated required acceleration / deceleration; and a shape acquisition device (23, 27, 28, 29) which is configured to acquire road shape information which represents a shape of a road at a position which is a predetermined distance away from the vehicle along a direction of movement of the vehicle, where the control unit (20) is configured as follows: Determine whether a curved road exists in the direction of travel of the vehicle or not, based on the road shape information (step 615); Determine that a first control start condition is satisfied as the control start condition (step 625) if the magnitude of the physical quantity of a turning motion has changed from a value less than a first value to a value equal to or greater than the first value (step 630: Yes), in a case where it is determined that the curved road is not present (step 615: No); and Determine that a second control start condition is satisfied as the control start condition (step 625) if a quantity of the physical quantity of a turning motion has changed from a value that is less than a second value that is less than the first value to a value that is equal to or greater than the second value (step 620: Yes), in a case where it is determined that the curved road is present (step 615: Yes), where the control unit (20) is configured as follows: Starting an initial acceleration / deceleration control as an acceleration / deceleration control (step 550) when it is determined that the initial control start condition is met (step 1025: Yes); Starting a second acceleration / deceleration control as an acceleration / deceleration control (step 1020) if it is determined that the second control start condition is met (step 1015: Yes); and Calculating the required acceleration / deceleration in such a way that the required acceleration / deceleration value for the second acceleration / deceleration control is smaller than the required acceleration / deceleration value for the first acceleration / deceleration control. where the control unit (20) is set up when it is determined that the first control start condition is met, while the second acceleration / deceleration control is executed to start the first acceleration / deceleration control, to calculate the required acceleration / deceleration in such a way that the magnitude of a change in the required acceleration / deceleration per unit of time does not exceed a predetermined safeguard threshold (step 1420 to step 1435), in a time span from a start time at which the first acceleration / deceleration control is started to an end time at which a predetermined time has elapsed since the start time (step 1405: Yes). [2] Vehicle control unit, with: a sensor (22) configured to detect a physical quantity of a turning movement which varies depending on a state of a turning movement of a vehicle when the vehicle turns; an acceleration / deceleration device (40, 46, 50, 54) which is configured to vary the acceleration / deceleration of the vehicle; a control unit (20) which is configured to perform acceleration / deceleration control in order to: to determine whether the vehicle is traveling on a curved road or not by determining whether the physical magnitude of a turning movement satisfies a predetermined control start condition or not (steps 600 to 695); if it is determined that the vehicle is traveling on a curved road (step 540: Yes), calculate a required acceleration / deceleration to maintain the vehicle at a target speed depending on the curvature of the curved road, and control the acceleration / deceleration device to make the actual acceleration / deceleration of the vehicle equal to the calculated required acceleration / deceleration; and a shape acquisition device (23, 27, 28, 29) which is configured to acquire road shape information which represents a shape of a road at a position which is a predetermined distance away from the vehicle along a direction of movement of the vehicle, where the control unit (20) is configured as follows: Determine whether a curved road exists in the direction of travel of the vehicle or not, based on the road shape information (step 615); Determine that a first control start condition is satisfied as the control start condition (step 625) if the magnitude of the physical quantity of a turning motion has changed from a value less than a first value to a value equal to or greater than the first value (step 630: Yes), in a case where it is determined that the curved road is not present (step 615: No); and Determine that a second control start condition is satisfied as the control start condition (step 625) if a quantity of the physical quantity of a turning motion has changed from a value that is less than a second value that is less than the first value to a value that is equal to or greater than the second value (step 620: Yes), in a case where it is determined that the curved road exists (step 615: Yes) the vehicle control unit furthermore includes a steering angle changing device (60, 66) which is configured to change the steering angle of the vehicle, where the control unit (20) is configured as follows: Performing steering angle control to calculate a target steering angle to guide the vehicle along a lane, and controlling the steering angle change device to make an actual steering angle of the vehicle equal to the target steering angle; Determine whether a magnitude of the target steering angle is equal to or greater than a predetermined threshold angle (step 905) when it is determined that the curved road is present, based on the road shape information; Start the acceleration / deceleration control when the second control start condition is met (step 620: Yes), while the magnitude of the target steering angle is equal to or greater than the threshold angle (step 905: Yes); and Determine that a third control start condition is satisfied as the control start condition (Step 910: Yes) if a quantity of the physical quantity of a turning motion has changed from a value less than a third value to a value equal to or greater than the third value, while the quantity of the target steering angle is less than the threshold angle (Step 905: No), where the third value is less than the first value and greater than the second value.

Images