JP2007145227A - Steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering device capable of carrying out proper steering control at an exit of a curve. <P>SOLUTION: This steering device furnished with travelling road detection means 20, 21, slipping quantity detection means 20, 21 to detect slipping quantity from a specified position of a travelling road, an integrating means 30 to find an integrating term by integrating the slipping quantity and an calculation means 30 to calculate steering output to control a steering mechanism in accordance with the slipping quantity and the integrating term and to control the steering mechanism so that the vehicle travels along the specified position of the travelling road is furnished with curve radius detection means 20, 21, a curve exit determining means 30 to determine whether a vehicle position is the exit of a curved road or not and a vehicle moving direction detection means 30 and characteristically rests the integrating term when the vehicle moving direction and the steering controlling direction based on the integrating term coincide with each other in determining the vehicle position as the exit of the curved road in the middle of travelling on the curved road a curve radius of which is larger than a specified radius. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a steering apparatus that controls a steering mechanism so as to travel along a predetermined position on a traveling path.

  As a steering device, there is a lane keeping device that recognizes a lane from a captured image of a traveling road ahead of the vehicle and applies torque to the steering mechanism so that the vehicle travels along the center of the lane (see Patent Document 1). In the lane keeping device, the curve radius (road curvature) of the travel path from the recognized lane and the vehicle, the yaw angle of the vehicle with respect to the lane, the offset of the vehicle from the lane center, and the like are obtained. In the lane keeping device, the feedforward output is obtained based on the road curvature, the feedback output is obtained based on the yaw angle and the offset, and the output torque to be added to the steering mechanism is set from these outputs. Further, some lane keeping devices integrate an offset, and a feedback output based on the integral term also takes into account the output torque.

The road is provided with a road surface cant (transverse gradient) inclined in either the left or right direction of the road in consideration of the direction of drainage or the curve. In the case of a curved road, a road surface cant that normally lowers the inside of the curve is provided. Therefore, on a curved road, a force (lateral acceleration) directed toward the inside of the curve is applied to the vehicle by the road surface cant. As the inclination of the road surface cant increases, the lateral acceleration acting on the vehicle increases, and the vehicle may approach the inside of the curve from the lane center. In this case, in the lane keeping device, the integral term of the offset inside the curve is increased, and the torque in the curve outward direction is added to the output torque based on this integral term. In addition, since an upper limit is set for the feedforward output, on a curved road, as the vehicle speed and the curve radius are smaller, the feedforward output becomes insufficient, and the vehicle may approach the outside of the curve from the center of the lane. In this case, in the lane keeping device, the integral term of the offset outside the curve is increased, and the torque in the curve inner direction is added to the output torque based on the integral term. In the case of a curved road, the lane keeping device uses such an integral term of offset to compensate for the influence of the road surface cant and insufficient feedforward so that the vehicle can travel along the center of the lane.
JP 2001-10518 A

  When a straight road or a curved road with a different turning direction is entered from the curved road, the inclination direction of the road surface cant changes, and torque based on the integral term of the offset obtained during traveling on the curved road becomes unnecessary. Therefore, when entering a straight road or a curved road with a different turning direction, in the case of an integral term outside the curve (when the direction of applying torque based on the integral term is the curve inside direction), the curve is involved (the steering wheel switchback delay) In the case of an integral term inside the curve (when the direction of applying torque based on the integral term is the direction outside the curve), there is a possibility of causing a lane departure.

  Therefore, an object of the present invention is to provide a steering device that can perform appropriate steering control at a curve exit.

  A steering apparatus according to the present invention includes a travel path detection unit that detects a travel path of a vehicle, a shift amount detection unit that detects a shift amount from a predetermined position of the travel path of the vehicle, and an integral term that integrates the shift amount. Integrating means for calculating the steering angle, and calculating means for calculating a steering output for controlling the steering mechanism on the basis of an amount of deviation from the predetermined position of the travel path of the vehicle and an integral term, and the vehicle follows the predetermined position on the travel path. In the steering device that controls the steering mechanism so as to travel, a curve radius detection unit that detects a curve radius of a road, a curve exit determination unit that determines whether or not the vehicle position is an exit of a curved road, and a traveling direction of the vehicle Vehicle traveling direction detection means for detecting the vehicle, and when the vehicle exit is determined to be the exit of the curve road by the curve exit determination means while traveling on a curved road having a curve radius detected by the curve radius detection means greater than or equal to a predetermined radius, Characterized by resetting the integral term when the steering control direction based on the vehicle traveling direction and the integral term which is detected in the row direction detection means coincide.

  In this steering device, the travel path is detected by the travel path detection means. In the steering device, a deviation amount of the vehicle position with respect to a predetermined position on the travel path is detected by the deviation amount detection means, and the integral term is obtained by integrating the deviation amount by the integration means. Further, in the steering device, the steering output for controlling the steering mechanism is calculated based on the deviation amount and the integral term by the calculation means so as to reduce the deviation amount (so as not to increase the integral term). The steering mechanism is controlled so that the vehicle travels along a predetermined position on the travel path by the output. When there is a deviation amount (and hence an integral term) on the one side in the left-right direction of the travel path, the vehicle is shifted toward one direction with respect to a predetermined position on the travel path. The steering mechanism is controlled. Therefore, the steering control direction is determined depending on which side in the left-right direction the deviation amount or the integral term exists. In the steering apparatus, the curve radius detection means detects the curve radius of the travel road, the curve exit determination means determines whether the vehicle is an exit of the curve road, and the vehicle travel direction detection means detects the vehicle travel direction. To do. When the steering device determines that the vehicle position has reached the curve exit while traveling on a curved road with a curve radius equal to or greater than a predetermined radius (a relatively gentle curve), the steering control direction based on the integral term is the vehicle traveling direction. The integral term is reset when the values coincide with each other, and the integral term is not reset otherwise. The larger the curve radius, the smaller the integral term because the influence of the road surface cant (the larger the curve radius, the less the slope of the road surface cant) and the feedforward output shortage are small. Basically, the integral term is reset at the curve exit. There is no need. Therefore, in this case, the steering apparatus adds a feedback output based on the integral term to the steering output for controlling the steering mechanism. However, when the traveling direction of the vehicle and the steering control direction based on the integral term are the same direction, the vehicle is further steered to the traveling direction side of the vehicle by the feedback output based on the integral term, and the vehicle is Deviation from the predetermined position. Therefore, in this case, the steering device resets the integral term, and does not add the feedback output based on the integral term to the steering output for controlling the steering mechanism. As a result, no lane departure or curve entrainment occurs. As described above, in this steering apparatus, it is possible to perform appropriate steering control by eliminating feedback output based on an unnecessary integral term at the exit of a curved road having a large curve radius.

  In the above steering apparatus of the present invention, the vehicle traveling direction detection means may be configured to detect the traveling direction based on the angle of the vehicle with respect to the traveling path.

  In this steering apparatus, the traveling direction is detected based on the angle of the vehicle with respect to the travel path by the vehicle traveling direction detection means. Since the steering device detects the traveling road, the traveling direction of the vehicle can be obtained easily and with high accuracy by using the traveling road.

  In the above steering apparatus of the present invention, the curve exit determining means may be configured to determine based on the curve radius.

  In this steering apparatus, it is determined by the curve exit determination means whether the vehicle is a curve exit based on the curve radius (road curvature). In the case of a curved road, the curve radius decreases when the vehicle enters the curve (the road curvature increases), and after reaching the minimum curve radius, the curve radius increases (the road curvature decreases) as it approaches the curve exit. Therefore, the exit of the curved road can be estimated easily and with high accuracy by changing the curve radius (road curvature).

  In the steering apparatus according to the present invention, a travel path detection unit that detects a travel path of the vehicle, a shift amount detection unit that detects a shift amount from a predetermined position of the travel path of the vehicle, and an integral term that integrates the shift amount. Integrating means for calculating the steering angle, and calculating means for calculating a steering output for controlling the steering mechanism on the basis of an amount of deviation from the predetermined position of the travel path of the vehicle and an integral term, and the vehicle follows the predetermined position on the travel path. In the steering apparatus that controls the steering mechanism so as to travel, the vehicle includes a curve radius detection unit that detects a curve radius of the road and a curve exit determination unit that determines whether or not the vehicle position is an exit of a curve road, The integral term is reset when the curve exit determining means determines that the vehicle position is the exit of the curved road while traveling on a curved road having a curve radius detected by the detecting means not more than a predetermined radius.

  In this steering device, similarly to the steering device described above, the steering mechanism is controlled so that the vehicle travels along a predetermined position on the travel path based on the deviation amount and the integral term. In the steering device, the curve radius detecting means detects the curve radius of the traveling road, and the curve exit determining means determines whether or not the vehicle position is the exit of the curved road. Then, the steering device resets the integral term when it is determined that the vehicle position has come to the curve exit while traveling on a curve road (a relatively steep curve) having a curve radius equal to or less than a predetermined radius. The smaller the curve radius, the greater the influence of the road surface cant (the smaller the curve radius, the greater the slope of the road surface cant) and the lack of feedforward output. Deviates from a predetermined position on the road. Therefore, in this case, the steering device resets the integral term, and does not add the feedback output based on the integral term to the steering output for controlling the steering mechanism. As a result, no lane departure or curve entrainment occurs. As described above, in this steering apparatus, it is possible to perform appropriate steering control by eliminating feedback output due to an unnecessary integral term at the exit of a curved road having a small curve radius.

  In the steering apparatus according to the present invention, a travel path detection unit that detects a travel path of the vehicle, a shift amount detection unit that detects a shift amount from a predetermined position of the travel path of the vehicle, and an integral term that integrates the shift amount. Integrating means for calculating the steering angle, and calculating means for calculating a steering output for controlling the steering mechanism on the basis of an amount of deviation from the predetermined position of the travel path of the vehicle and an integral term, and the vehicle follows the predetermined position on the travel path. In the steering device that controls the steering mechanism so that the vehicle travels, the vehicle includes a curve radius detection unit that detects a curve radius of the road and a curve direction detection unit that detects a direction in which the curve road is bent. The timing for resetting the integral term when the turning direction of the curved road detected by the curve direction detection means coincides with the steering control direction based on the integral term while traveling on a curved road having a curve radius equal to or less than the predetermined radius. Wherein the advancing the timing based on the exit of the curved road and grayed.

  In this steering device, similarly to the steering device described above, the steering mechanism is controlled so that the vehicle travels along a predetermined position on the travel path based on the deviation amount and the integral term. In the steering device, the curve radius detecting means detects the road curve radius, and the curve direction detecting means detects the direction of the curve road to bend. Then, in the steering device, the timing at which the integral term is reset when the turning direction of the curved road coincides with the steering control direction based on the integral term while traveling on a curved road having a radius less than or equal to the predetermined radius is the reset timing at the curve exit. Faster (that is, reset the integral term on the curve entrance side than the curve exit). The smaller the curve radius, the larger the feedforward output shortage, and the larger the integral term on the side different from the curve direction of the curve path. In this case, the turning direction of the curved road and the steering control direction based on the integral term become the same direction, and there is a possibility that entrainment occurs near the curve exit. Therefore, in this case, the steering device resets the integral term on the curve entrance side from the curve exit, and does not add the feedback output based on the integral term to the steering output for controlling the steering mechanism before reaching the curve exit. As a result, no curve entrainment occurs. As described above, in this steering apparatus, it is possible to perform appropriate steering control by eliminating feedback output due to an unnecessary integral term in the vicinity of the exit of a curved road having a small curve radius.

  The steering device according to the present invention includes a steering direction detection unit that detects a steering direction by the driver, and the steering direction by the driver detected by the steering direction detection unit is different from the bending direction of the curve road detected by the curve direction detection unit. Alternatively, the timing for resetting the integral term may be advanced.

  In this steering apparatus, the steering direction by the driver is detected by the steering direction detection means. And, in the steering device, when the curved road having a curved radius equal to or less than a predetermined radius is traveling, the direction of the curved road is coincident with the steering control direction based on the integral term, and the driver's steering direction is different from the curved direction of the curved road. Advance the timing to reset the integral term. When exiting a curve road having a small curve radius, the driver usually turns the steering wheel back before reaching the curve exit, and performs a steering operation in preparation for the next straight or reverse curve road. Therefore, the vicinity of the curve exit (the curve entrance side) can be estimated with high accuracy according to the steering direction of the driver. On the other hand, if the driver is still performing the steering operation in the direction of the curved road, if the feedback output based on the integral term is not taken into account, the steering feeling is lowered. Therefore, in this steering apparatus, the timing for resetting the integral term is determined with high accuracy in consideration of the steering direction of the driver.

  In the steering apparatus of the present invention, it is preferable to reset the integral term when approaching the exit of the curved road.

  In this steering device, the integral term is reset when approaching the exit of the curve road before reaching the curve exit, and the feedback output based on the integral term is not added to the steering output for controlling the steering mechanism. In this way, the influence of the integral term is eliminated when approaching the curve exit, and curb entrainment is reliably prevented.

  The traveling road is, for example, a traveling lane or a traveling road when there is no lane. The predetermined position of the travel path is, for example, the center of the travel path (lane). The steering output when controlling the steering mechanism may be any output that can change the steering state such as the steering torque and the steering angle. As the travel path detection means, for example, when detecting based on a captured image captured by the imaging means, when detecting based on processing by the navigation system and map information, when detecting using various sensors, road-to-vehicle communication, etc. Information may be obtained from outside the vehicle using. The steering control direction is a direction in which a steering torque, a steering angle, or the like acts as an output in the steering device, and is a right direction and a left direction.

  The present invention eliminates feedback output due to an unnecessary integral term at a curve exit and can perform appropriate steering control.

  Hereinafter, embodiments of a steering apparatus according to the present invention will be described with reference to the drawings.

  In the present embodiment, the steering device according to the present invention is applied to a lane keeping device. The lane keeping device according to the present invention recognizes a white line from an image captured by a camera and adds auxiliary steering torque toward the center of the left and right white lines (lanes), which is a travel path, in order to assist steering by a driver. To do.

  A lane keeping device 1 according to the present embodiment will be described with reference to FIGS. FIG. 1 is a configuration diagram of a lane keeping device according to the present embodiment. FIG. 2 is a control block diagram of the lane keeping device of FIG. FIG. 3 is a map of output torque with respect to the target lateral acceleration in the lane keeping device of FIG.

  The lane keeping device 1 sets an output torque necessary for traveling in the center of the lane, and uses the electric power steering device to add the output torque to the steering mechanism. At that time, the lane keeping device 1 is based on the road curvature γ (curve radius R), the direction of the vehicle with respect to the lane (yaw angle θ), the displacement of the vehicle position with respect to the lane center (offset D), and the integral term of the offset. A target lateral acceleration is set, and an output torque is obtained from the target acceleration. In particular, the lane keeping device 1 resets an unnecessary integral term at the curve exit or in the vicinity of the curve exit (the curve entrance side) in order to add an appropriate output torque at the curve exit. The lane keeping device 1 includes a steering torque sensor 10, a vehicle speed sensor 11, a CCD [Charge Coupled Device] camera 20, an image processing unit 21, and an ECU [Electronic Control Unit] 30, and uses an electric power steering device 40.

  In a steering mechanism in a vehicle, steered wheels (left and right front wheels FR, FL) are steered in accordance with an operation on the steering wheel 2 by a driver. The steering wheel 2 is fixed to one end of the steering shaft 3. The steering shaft 3 rotates as the steering wheel 2 rotates. A rack bar 5 is connected to the other end of the steering shaft 3 via a steering gear box 4. The steering gear box 4 has a function of converting the rotational movement of the steering shaft 3 into the linear movement of the rack bar 5 in the axial direction. Both ends of the rack bar 5 are connected to the hub carriers of the wheels FL and FR via the knuckle arm 6. Thus, the wheels FL and FR are steered via the steering shaft 3 and the steering gear box 4 (rack bar 5) when the steering wheel 2 is rotated.

  The electric power steering device 40 drives and controls a motor 42 by an EPS [Electric Power Steering] ECU 41, and assists steering by the driver by a driving torque by the motor 42. The EPS ECU 41 sets an assist torque based on the steering torque generated by the driver's steering, and drives and controls the motor 42 in order to generate the assist torque by the motor driver. In particular, EPSECU 41, when receiving the output torque signal from ECU 30, multiplies the output torque indicated by the output torque signal by a predetermined coefficient, adds the multiplied value (additional torque) to the assist torque, and outputs the assist torque + In order to generate the additional torque, the motor 42 is driven and controlled. The driving torque by the motor 42 is added to the steering mechanism, and the torque by the motor 42 is applied to the steering mechanism in addition to the steering torque by the driver. Note that the steering torque, assist torque, and output torque (additional torque) are represented by plus / minus values, and the sign indicates the direction. For each torque, a positive value indicates torque in the right direction, and a negative value indicates torque in the left direction.

  A ball screw groove is formed on a part of the outer peripheral surface of the rack bar 5, and a ball nut having a ball screw groove corresponding to the ball screw groove on the inner peripheral surface is fixed to the rotor of the motor 42. A plurality of bearing balls are accommodated between the pair of ball screw grooves. When the motor 42 is driven, the rotor can be rotated and moved in the axial direction of the rack bar 5 (that is, assisting the steering). be able to). At this time, the motor 42 applies a torque corresponding to the drive current supplied from the motor driver of the ECPECU 41 to the rack bar 5.

  The steering torque sensor 10 is a sensor that detects the steering torque input from the steering wheel 2. The steering torque sensor 10 transmits the detected steering torque to the ECU 30 as a steering torque signal. The vehicle speed sensor 11 is a sensor that detects the speed of the vehicle. The vehicle speed sensor 11 transmits the detected vehicle speed to the ECU 30 as a vehicle speed signal.

  The CCD camera 20 is attached in front of a vehicle on which the lane keeping device 1 is mounted (for example, built in a rearview mirror). At this time, the CCD camera 20 is mounted such that its optical axis direction coincides with the traveling direction of the vehicle. The CCD camera 20 images a road ahead of the vehicle and acquires a captured color image (for example, an image by RGB [Red Green Blue]). The CCD camera 20 transmits the captured image data to the image processing unit 21 as an imaging signal. The CCD camera 20 has a wide imaging range in the left-right direction, and can sufficiently image the left and right (a pair of) white lines indicating the traveling lane. Although the CCD camera 20 is color, it may be a black and white camera as long as it can acquire an image that can recognize a white line on the road.

  The image processing unit 21 takes an image signal from the CCD camera 20 and recognizes a pair of white lines (road lane lines) indicating the lane in which the vehicle is traveling from the image data of the image signal. In the captured image, the brightness difference between the road surface and the white line drawn on it is large, so the white line that divides the lane is relatively easy to detect by edge detection etc., which is convenient for detecting the lane ahead of the vehicle. Good.

  Then, the image processing unit 21 calculates a lane width and a line passing through the center of the pair of white lines (that is, the center of the lane) from the recognized pair of white lines. Further, the image processing unit 21 calculates the radius of the center of the lane (curve radius R), and calculates the road curvature γ (= 1 / R) from the curve radius R. Further, the image processing unit 21 calculates an angle (yaw angle θ) formed between the center line of the lane and the center axis in the front-rear direction of the vehicle and a lateral shift amount (offset D) of the vehicle center of gravity with respect to the center line of the lane. To do. Then, the image processing unit 21 transmits the recognized pair of white line information and each calculated information to the ECU 30 as image signals.

  The curve radius R, the road curvature γ, the yaw angle θ, and the offset D are represented by plus / minus values, and the sign indicates the direction. As for the curve radius R and the road curvature γ, a positive value indicates the right direction and a negative value indicates the left direction. Therefore, the direction of the curve road can be determined from the curve radius R and the road curvature γ. When the curve radius R and the road curvature γ are positive values, the curve road is a right turn, and when the curve radius is negative, the curve road is a left turn. It is. The yaw angle θ has a positive value in the left direction and a negative value in the right direction. The offset D (integrated value of the offset D) has a positive value on the left side of the lane and a negative value on the right side of the lane. In the present embodiment, the CCD camera 20 and the image processing unit 21 correspond to a travel path detection unit, a deviation amount detection unit, a curve radius detection unit, and a curve direction detection unit described in the claims.

  The ECU 30 includes a CPU [Central Processing Unit], a ROM [Read Only Memory], a RAM [Random Access Memory], and the like, and comprehensively controls the lane keeping device 1. The ECU 30 takes in the image signal from the image processing unit 21 and takes in the detection signal from each of the sensors 10 and 11 at regular time intervals. Then, in the ECU 30, when the lane keeping device 1 is activated by an operation by the driver, various information (road curvature γ, yaw angle θ, offset D) shown in the image signal so that the vehicle travels near the center of the lane. ) And the vehicle speed V, an output torque (target lateral acceleration) is set, and an output torque signal indicating the output torque is transmitted to the electric power steering device 40 (EPS ECU 41).

  With reference to FIG. 2, a basic process for obtaining the output torque in the ECU 30 will be described. In the present embodiment, this basic processing in the ECU 30 corresponds to the calculation means described in the claims.

In ECU 30, multiplied by the gain K _gamma to the multiplication value of the road curvature gamma and vehicle speed V in the F / F controller 31 calculates the yaw rate omega _gamma. The yaw rate ω _γ is a yaw rate that generates a target lateral acceleration necessary for the vehicle to travel along the curve, and is 0 on a straight road. The yaw rate ω _γ is a feedforward output of lane keeping. An upper limit is set for the feedforward output.

The ECU 30 calculates a deviation ΔD = (D ₀ −D) between the offset D and the target offset D ₀ (for example, 0). Then, the ECU 30 integrates the deviation ΔD with time in the integrator 32 to calculate the integrated value ID of the offset. Further, the ECU 30, multiplied by the gain _{K D} the deviation ΔD with multiplying the gain _{K ID} to the integral value ID, and calculates a yaw rate omega _D by adding the two multiplied values. The yaw rate ω _D is a yaw rate that generates a target lateral acceleration necessary for converging the offset (integral value). In particular, the target lateral acceleration generated based on the integral value ID is a target lateral acceleration for compensating for the influence of a road surface cant and insufficient feedforward. In the present embodiment, the integrator 32 corresponds to the integrating means described in the claims.

The ECU 30 calculates a deviation Δθ = (θ ₀ −θ) between the yaw angle θ and the target yaw angle θ ₀ (for example, 0). Then, the ECU 30, multiplied by the gain K _theta the deviation [Delta] [theta], and calculates the yaw rate omega _theta. The yaw rate ω _θ is a yaw rate that generates a target lateral acceleration necessary for converging the yaw angle. Yaw rate ω _D and the yaw rate _ω θ is a feedback output of the lane keep.

The ECU 30 calculates the target yaw rate ω by adding the three calculated yaw rates ω _γ , ω _D , and ω _θ . In the ECU 30, the target lateral acceleration calculator 33 multiplies the target yaw rate ω by the vehicle speed V to calculate the target lateral acceleration G. The target lateral acceleration G is represented by a plus value / minus value, and the sign indicates the direction. For the target lateral acceleration G, a positive value indicates a lateral acceleration in the right direction, and a negative value indicates a lateral acceleration in the left direction. The direction of the output torque applied to the steering mechanism by lane keeping (lane keeping steering direction) is determined by the change in the target lateral acceleration G. For example, output torque is added in the right direction when the target lateral acceleration increases by a predetermined amount or more, and output torque is added in the left direction when the target lateral acceleration decreases by a predetermined amount or more.

  In the ECU 30, an output torque T corresponding to the target lateral acceleration G is obtained by the output torque calculator 34. The output torque calculator 34 holds the output torque map shown in FIG. 3, and the output torque T corresponding to the target lateral acceleration G is obtained from the output torque map with reference to the output torque map. As the output torque map, a map TI at the time of increasing and a map TR at the time of switching back are set, and hysteresis is provided between the two maps TI and TR. This hysteresis is for compensating for friction in the steering mechanism, and increases the output torque when increasing the cut and decreases the output torque when switching back. In the output torque map, the direction in which the output torque T (target lateral acceleration G) increases to the plus side is the lane keeping steering direction to the right, and the output torque T (target lateral acceleration G) increases to the minus side. The steering direction of the lane keep is the left direction. The output torque calculator 34 selects either the map TI at the time of increase or the map TR at the time of return according to the sign of the lane keep steering direction and the target lateral acceleration G. Then, the output torque calculator 34 extracts the output torque T corresponding to the value of the target lateral acceleration G from the selected map. Then, the ECU 30 transmits an output torque signal indicating the output torque T to the EPS ECU 41.

  In particular, the ECU 30 resets the integral value ID as needed near the curve exit or near the curve exit so as not to add output torque based on the integral value ID that is unnecessary at the curve exit or near the curve exit. For this purpose, the ECU 30 performs a small R curve determination process, a large R curve determination process, a vehicle traveling direction determination process, a driver steering direction determination process, a curve exit vicinity determination process, before a process in the integrator 32 at regular intervals. An integral output reset determination process is performed, and an integral output reset process is performed in the integrator 32. Here, an outline of a process for resetting an unnecessary integral value ID in the ECU 30 will be described, and details of each process described above will be described when the operation of the lane keeping device 1 is described.

  In the present embodiment, the vehicle traveling direction determination process in the ECU 30 corresponds to the vehicle traveling direction detection means described in the claims, and the small R curve determination process and the integral output reset determination process in the ECU 30 are in the claims. The driver steering direction determination process in the ECU 30 corresponds to the steering direction detection means described in the claims.

  The ECU 30 uses eight flags: a small R curve turning flag, a curve turning flag, a vehicle right side traveling flag, a vehicle left side traveling flag, a driver right steering flag, a driver left steering flag, a curve exit vicinity flag, and an integral output reset flag. The ECU 30 sets each flag in each process at regular time intervals. The ECU 30 also updates the previous value of each flag for seven flags other than the integral output reset flag at regular intervals.

  The small R curve turning flag is a flag indicating whether or not the traveling path is a relatively steep curve (hereinafter referred to as “small R curve”), and is ON when the small R curve is turning. OFF when not turning. The curve turning flag is a flag indicating whether or not the traveling path is a relatively gentle curve (hereinafter, referred to as “large R curve”), and is ON when the large R curve is turning, and during the large R curve turning. Otherwise (when running on a straight road), it is OFF. Incidentally, when the small R curve turning flag is ON, the curve turning flag is always ON. Further, when the curve turning flag is OFF, the traveling road is a straight road.

  The vehicle rightward progress flag is a flag indicating whether or not the vehicle is traveling to the right side of the lane, and is ON when the vehicle is traveling to the right side, and is OFF when the vehicle is not traveling to the right side. The vehicle left side progress flag is a flag indicating whether or not the vehicle is traveling to the left side of the lane, and is ON when the vehicle is traveling to the left side, and is OFF when the vehicle is not traveling to the left side. When both the vehicle right side progress flag and the vehicle left side progress flag are OFF, the vehicle is traveling straight.

  The driver right steering flag is a flag indicating whether or not the driver is steering the steering wheel 2 in the right direction, and is ON when the driver is steering right, and OFF when the driver is not steering right. is there. The driver left steering flag is a flag indicating whether or not the driver is steering the steering wheel 2 in the left direction, and is ON when the driver is steering left, and is OFF when the driver is not steering left. is there. Incidentally, when both the driver right steering flag and the driver left steering flag are OFF, the steering force by the driver is not input.

  The curve exit flag is a flag indicating whether or not the vehicle has not reached the curve exit while turning on a curved road, but has reached a position close to the curve exit (hereinafter referred to as “around the curve exit”). It is ON when near the curve exit, and OFF when not near the curve exit. The integration output reset flag is a flag for determining whether or not to reset the integration value ID, and is ON when resetting, and is OFF when not resetting.

  At certain time intervals, the ECU 30 determines whether or not the small R curve is turning based on the road curvature by the small R curve determination process, and sets the small R curve turning flag. Further, the ECU 30 determines whether or not a curve is turning based on the road curvature by the large R curve determination process, and sets a curve turning flag. Further, the ECU 30 determines whether the vehicle is traveling in the right direction and whether the vehicle is traveling in the left direction based on the yaw angle θ by the vehicle traveling direction determination process, and determines whether the vehicle is traveling on the right side of the vehicle. Set the progress flag. Further, the ECU 30 determines whether or not the driver is steering in the right rotation direction and whether or not the driver is steering in the left rotation direction based on the steering torque input by the driver in the driver steering direction determination process. A steering flag and a driver left steering flag are set.

  Then, the ECU 30 determines whether or not the vehicle has reached the vicinity of the curve exit based on the change in the road curvature by the curve exit vicinity determination process, and sets the curve exit vicinity flag. In the case of a curved road, the road curvature increases from 0 or near 0, reaches the maximum road curvature, then decreases from the maximum road curvature and changes to 0 or near 0, and the road curvature changes. The vicinity of the curve exit is determined by observing the change in curvature.

  Further, the ECU 30 determines whether or not it is a small R curve and a curve exit based on the small R curve turning flag and its previous value by the integral output reset determination process, and if this determination condition is satisfied, the integral output reset flag Set to ON. With a small R curve, the feedforward output shortage may occur due to the influence of the upper limit of the feedforward output as the vehicle has a higher vehicle speed or smaller curve radius. In this case, the offset OF1 is generated outside the lane of the vehicle, the integral value outside the curve is increased, and torque in the inner direction of the curve is added based on this integral term (see FIG. 13). For this reason, when the vehicle enters a straight road or a curve with a different turning direction from the exit of the small R curve curve, there is a possibility that the entanglement of the curve may occur due to the effect of the lane keeping torque added to the inside of the small R curve. (Refer to the travel locus ML1 ′ of the vehicle in FIG. 13). In the small R curve, the lateral acceleration in the curve inner direction acting on the vehicle by the road surface cant increases as the slope of the lower road surface cant increases toward the inside of the curve. In this case, the offset OF2 increases inside the lane of the vehicle, the integral value inside the curve increases, and torque in the outward direction of the curve is added based on this integral term (see FIG. 14). Therefore, if the vehicle enters a straight road or a curve with a different turning direction from the exit of the curve of the small R curve, a lane departure may occur due to the action of torque applied to the outside of the small R curve (see FIG. 14 vehicle travel locus ML2 ′). Accordingly, the lane keeping device 1 always resets the integral term at the curve exit of the small R curve, and eliminates the feedback output based on the unnecessary integral term.

  Further, the ECU 30 determines whether or not it is near the curve exit of the small R curve based on the small R curve turning flag and the curve exit vicinity flag by the integral output reset determination process. Based on the radius R, the integral value ID, the driver right steering flag, and the driver left steering flag, the direction in which the additional torque based on the integral value acts coincides with the curve direction, and the driver steering direction does not coincide with the curve direction. If this determination condition is satisfied, the integral output reset flag is set to ON. Especially in the small R curve, when the direction of the applied torque based on the integral value matches the direction of the curve (that is, when the torque is applied inward of the curve based on the integral term), The higher the vehicle speed, the higher the possibility of curving. Further, when the driver is not steering in the direction of the small R curve, the driver prepares for the straight path or the curve that enters next from the small R curve. In particular, the smaller the curve radius, the more the driver turns back the steering wheel 2 before the curve exit. On the contrary, when the driver is steering in the direction of the small R curve, it is not preferable in terms of steering feeling to eliminate the additional torque based on the integral term. Therefore, in the lane keeping device 1, even in the case of a small R curve, when the above condition is satisfied in the vicinity of the curve exit, the timing for resetting the integral term is advanced from the curve exit, and the feedback output by the unnecessary integral term is eliminated early.

  Further, the ECU 30 determines whether or not it is a curve exit of a large R curve based on the curve turning flag and its previous value by an integral output reset determination process. It is determined whether or not the direction in which the additional torque based on the integral value is applied matches the vehicle traveling direction based on the traveling flag and the vehicle left traveling flag. If this determination condition is satisfied, the integral output reset flag is turned ON. Set. In the case of a large R curve, the feedforward output shortage does not occur as the curve radius increases. Further, in the large R curve, since the slope of the low road surface cant is small inside the curve, the lateral acceleration in the curve inside direction acting on the vehicle by the road surface cant is small, and no lane departure occurs. Therefore, in the lane keeping device 1, basically, the integral term is not reset at the curve exit of the large R curve, and a feedback output based on the integral term is applied. However, when the traveling direction of the vehicle and the direction of the additional torque based on the integral term are the same direction, the vehicle is further steered to the traveling direction side of the vehicle by the additional torque based on the integral term, and the offset on the traveling direction side of the vehicle Becomes larger. Therefore, the lane keeping device 1 resets the integral term when the above condition is satisfied even in the case of a large R curve, and eliminates feedback output due to an unnecessary integral term.

  When the integral output reset flag is set, the integrator 32 of the ECU 30 resets the integral value ID based on the integral output reset flag or continues the time integration with the offset D by the integral output reset process.

  The operation of the lane keeping device 1 will be described with reference to FIGS. In particular, the small R curve determination process in the ECU 30 will be described with reference to the flowchart of FIG. 4, the large R curve determination process will be described with reference to the flowchart of FIG. 5, and the vehicle traveling direction determination process will be described with reference to FIGS. The driver steering direction determination process will be described with reference to the flowcharts of FIGS. 8 and 9, the curve exit vicinity determination process will be described with reference to the flowchart of FIG. 10, and the integral output reset determination process will be described. Will be described with reference to the flowchart of FIG. 11, and the integral output reset process will be described with reference to the flowchart of FIG. FIG. 4 is a flowchart showing a flow of small R curve determination processing in the ECU of the lane keeping device of FIG. FIG. 5 is a flowchart showing a flow of large R curve determination processing in the ECU of the lane keeping device of FIG. FIG. 6 is a flowchart showing the flow of the right side travel determination part of the vehicle travel direction determination process in the ECU of the lane keeping device of FIG. FIG. 7 is a flowchart showing the flow of the left side travel determination part of the vehicle travel direction determination process in the ECU of the lane keeping device of FIG. FIG. 8 is a flowchart showing the flow of the right steering determination part of the driver steering direction determination process in the ECU of the lane keeping device of FIG. FIG. 9 is a flowchart showing the flow of the left steering determination part of the driver steering direction determination process in the ECU of the lane keeping device of FIG. FIG. 10 is a flowchart showing the flow of the curve exit vicinity determination process in the ECU of the lane keeping device of FIG. FIG. 11 is a flowchart showing a flow of integral output reset determination processing in the ECU of the lane keeping device of FIG. FIG. 12 is a flowchart showing the flow of the integral output reset process in the ECU of the lane keeping device of FIG.

  The steering torque sensor 10 detects the steering torque input from the steering wheel 2 and transmits a steering torque signal indicating the steering torque to the ECU 30. The vehicle speed sensor 11 detects the vehicle speed and transmits a vehicle speed signal indicating the vehicle speed to the ECU 30.

  The CCD camera 20 captures the front of the vehicle and transmits data of the captured image to the image processing unit 21 as an imaging signal. The image processing unit 21 recognizes a pair of white lines that divide the lane from the captured image. Then, the image processing unit 21 calculates the lane width, the lane center line, the lane center curve radius R, the road curvature γ, the yaw angle θ, and the vehicle offset D from the pair of white lines. Further, the image processing unit 21 transmits the information on the pair of white lines and the calculated information to the ECU 30 as image signals.

  The ECU 30 receives a steering torque signal, a vehicle speed signal, and an image signal at regular intervals. Then, the ECU 30 acquires the curve radius R, road curvature γ, yaw angle θ, and offset D from the steering torque, vehicle speed, and image signal, and filters each of these input data.

  The ECU 30 updates the small R curve turning flag (previous value) with the previously set value of the small R curve turning flag at regular time intervals (S10 in FIG. 4). Then, the ECU 30 determines whether or not the small R curve turning flag (previous value) = OFF and the absolute value of the road curvature γ is greater than C1 (S11 in FIG. 4). C1 is a threshold value for determining whether the traveling road is a small R curve based on the road curvature. When the determination condition of S11 is satisfied, the ECU 30 increments the small R curve determination establishment timer (S12 of FIG. 4). On the other hand, when the determination condition of S11 is not satisfied, the ECU 30 resets the small R curve determination establishment timer (S13 in FIG. 4). The small R curve determination establishment timer is a timer for determining that the small R curve is turning when the absolute value of the road curvature γ is greater than C1 to some extent when the previous small R curve determination flag is OFF. . Since the road curvature γ is obtained from the lane recognized from the captured image, it may be affected by camera noise. Therefore, it is determined that the vehicle is turning on the small R curve only when it is determined that the absolute value of the road curvature γ is greater than C1 for a predetermined number of times.

  The ECU 30 determines whether or not the small R curve turning flag (previous value) = ON and the absolute value of the road curvature γ is smaller than C2 (S14 in FIG. 4). C2 is a threshold value for determining whether the traveling road is a small R curve based on the road curvature, and is a value smaller than C1. When the determination condition of S14 is satisfied, the ECU 30 increments the small R curve determination cancellation timer (S15 in FIG. 4). On the other hand, when the determination condition of S14 is not satisfied, the ECU 30 resets the small R curve determination cancellation timer (S16 in FIG. 4). The small R curve determination release timer is a timer for determining that the small R curve is not turning when the absolute value of the road curvature γ is less than C2 to some extent when the previous small R curve determination flag is ON. is there. Since the road curvature γ may be affected by camera noise as described above, the vehicle is turning on a small R curve only when it is determined that the absolute value of the road curvature γ is smaller than C2 for a predetermined number of times. It is determined that it is not.

  The ECU 30 determines whether or not the small R curve turning flag (previous value) = OFF (S17 in FIG. 4). When it is determined in S17 that the small R curve turning flag (previous value) = OFF, the ECU 30 determines whether or not the small R curve determination establishment timer is greater than T0 (S18 in FIG. 4). If it is determined in S18 that the small R curve determination establishment timer is greater than T0, the ECU 30 has a state in which the absolute value of the road curvature γ is greater than C1 for a predetermined time when the previous small R curve determination flag is OFF. Then, the small R curve turning flag is set to ON (small R curve turning) (S20 in FIG. 4). On the other hand, if the small R curve determination establishment timer is determined to be T0 or less in S18, the state where the absolute value of the road curvature γ is greater than C1 does not continue for a predetermined time when the previous small R curve determination flag is OFF. The ECU 30 sets the small R curve turning flag to OFF (not turning the small R curve) (S21 in FIG. 4). T0 is a threshold value for determining that the state in which the road curvature γ is greater than C1 (C3) continues for a predetermined time.

  On the other hand, when it is determined in S17 that the small R curve turning flag (previous value) = ON, the ECU 30 determines whether or not the small R curve determination cancellation timer is greater than T1 (S19 in FIG. 4). If it is determined in S19 that the small R curve determination cancellation timer is greater than T1, the state where the absolute value of the road curvature γ is smaller than C2 continues for a predetermined time when the previous small R curve determination flag is ON. Then, the small R curve turning flag is set to OFF (the small R curve is not turning) (S21 in FIG. 4). On the other hand, when the small R curve determination cancellation timer is determined to be T1 or less in S19, the state where the absolute value of the road curvature γ is smaller than C2 does not continue for a predetermined time when the previous small R curve determination flag is ON. In the ECU 30, the small R curve turning flag is set to ON (small R curve turning) (S20 in FIG. 4). T1 is a threshold value for determining that the state in which the road curvature γ is smaller than C2 (C4) continues for a predetermined time.

  Next, the ECU 30 updates the curve turning flag (previous value) with the previously set curve turning flag value at regular time intervals (S30 in FIG. 5). Then, the ECU 30 determines whether or not the curve turning flag (previous value) = OFF and the absolute value of the road curvature γ is greater than C3 (S31 in FIG. 5). C3 is a threshold value for determining whether the traveling road is a large R curve based on the road curvature, and is a value smaller than C1. When the determination condition of S31 is satisfied, the ECU 30 increments the curve determination establishment timer (S32 in FIG. 5). On the other hand, when the determination condition of S31 is not satisfied, the ECU 30 resets the curve determination establishment timer (S33 in FIG. 5). The curve determination establishment timer is a timer for determining that the vehicle is turning when the absolute value of the road curvature γ is greater than C3 to some extent when the previous curve determination flag is OFF. Since the road curvature γ may be affected by camera noise as described above, the vehicle is turning a large R curve only when it is determined that the absolute value of the road curvature γ is greater than C3 for a predetermined number of times. Is determined.

  The ECU 30 determines whether or not the curve turning flag (previous value) = ON and the absolute value of the road curvature γ is smaller than C4 (S34 in FIG. 5). C4 is a threshold value for determining whether or not the traveling road is a large R curve according to the road curvature (that is, a threshold value for determining whether or not the traveling road is a straight road), and is a value smaller than C2 and C3. is there. When the determination condition of S34 is satisfied, the ECU 30 increments the curve determination cancellation timer (S35 in FIG. 5). On the other hand, when the determination condition of S34 is not satisfied, the ECU 30 resets the curve determination cancellation timer (S36 in FIG. 5). The curve determination release timer is a timer for determining that the vehicle is not turning when the absolute value of the road curvature γ continues to be smaller than C4 to some extent when the previous curve determination flag is ON. Since the road curvature γ may be affected by camera noise as described above, the vehicle is turning on a large R curve only when it is determined that the absolute value of the road curvature γ is smaller than C4 for a predetermined number of times. It is determined that the vehicle is not running on a straight road.

  The ECU 30 determines whether or not the curve turning flag (previous value) = OFF (S37 in FIG. 5). When it is determined in S37 that the curve turning flag (previous value) = OFF, the ECU 30 determines whether or not the curve determination establishment timer is greater than T0 (S38 in FIG. 5). If it is determined in S38 that the curve determination establishment timer is greater than T0, the state in which the absolute value of the road curvature γ is greater than C3 continues for a predetermined time when the previous curve determination flag is OFF. Is set to ON (large R curve turning) (S40 in FIG. 5). On the other hand, if it is determined in S38 that the curve determination establishment timer is T0 or less, the state where the absolute value of the road curvature γ is greater than C3 does not continue for a predetermined time when the previous curve determination flag is OFF. The curve turning flag is set to OFF (not turning to a large R curve) (S41 in FIG. 5).

  On the other hand, when it is determined in S37 that the curve turning flag (previous value) = ON, the ECU 30 determines whether or not the curve determination cancellation timer is greater than T1 (S39 in FIG. 5). If it is determined in S39 that the curve determination cancellation timer is greater than T1, the state where the absolute value of the road curvature γ is smaller than C4 continues for a predetermined time when the previous curve determination flag is ON. Is set to OFF (not turning the large R curve) (S41 in FIG. 5). On the other hand, if the curve determination cancellation timer is determined to be T1 or less in S39, the ECU 30 does not continue for a predetermined time when the absolute value of the road curvature γ is smaller than C4 when the previous curve determination flag is ON. The curve turning flag is set to ON (large R curve turning) (S40 in FIG. 5).

  Next, the ECU 30 determines whether or not the vehicle right side advance flag (previous value) = OFF at regular time intervals (S50 in FIG. 6). When it is determined in S50 that the vehicle right side advance flag (previous value) = OFF, the ECU 30 determines whether or not the yaw angle θ of the vehicle is smaller than −Ang1 (S51 in FIG. 6). Ang1 (plus value) is a threshold value for determining whether the traveling direction of the vehicle is the right side or the left side of the lane based on the yaw angle. The yaw angle θ has a positive value on the left side and a negative value on the right side. Accordingly, when the yaw angle is larger than Ang1, a left yaw angle is generated so that the vehicle traveling direction can be determined as the left side. When the yaw angle is smaller than -Ang1, the right yaw angle is determined so that the vehicle traveling direction can be determined as the right side. Indicates that has occurred.

  When it is determined in S51 that the yaw angle θ is smaller than −Ang1, the ECU 30 increments the right side travel determination establishment timer (S52 in FIG. 6). On the other hand, when it is determined in S51 that the yaw angle θ is equal to or greater than -Ang1, the ECU 30 resets the right side travel determination establishment timer (S53 in FIG. 6). The right travel determination establishment timer is a timer for determining that the vehicle is traveling on the right side of the lane when the state where the yaw angle θ is smaller than −Ang1 continues to some extent when the previous vehicle right travel flag is OFF. Since the yaw angle θ is obtained from the lane recognized from the captured image, it may be influenced by camera noise. Therefore, it is determined that the vehicle is traveling on the right side of the lane only when it is determined that the yaw angle θ is smaller than −Ang1 for a predetermined number of times.

  Then, the ECU 30 determines whether or not the right side travel determination establishment timer is greater than T2 (S54 in FIG. 6). If it is determined in S54 that the right side travel determination establishment timer is greater than T2, the state where the yaw angle θ is smaller than −Ang1 continues for a predetermined time when the previous vehicle right side travel determination flag is OFF. The progress flag is set to ON (the vehicle is traveling on the right side of the vehicle) (S56 in FIG. 6). On the other hand, if the right side travel determination establishment timer is determined to be T2 or less in S54, the ECU 30 does not continue for a predetermined time when the yaw angle θ is smaller than -Ang1 when the previous vehicle right side travel determination flag is OFF. Then, the vehicle right side progress flag is set to OFF (the vehicle is not traveling on the right side of the lane) (S57 in FIG. 6). T2 is a threshold value for determining that the state where the yaw angle θ is smaller than −Ang1 (the state where the yaw angle θ is larger than Ang1) continues for a predetermined time.

  On the other hand, when it is determined in S50 that the vehicle right side advance flag (previous value) = ON, the ECU 30 determines whether or not the yaw angle θ of the vehicle is larger than −Ang2 (S55 in FIG. 6). Ang2 (plus value) is a threshold value for determining that the traveling direction of the vehicle is not the right side or the left side of the lane according to the yaw angle, and is a value smaller than Ang1. The yaw angle θ has a positive value on the left side and a negative value on the right side. Therefore, when the yaw angle is smaller than Ang2, the left yaw angle is not generated so that the vehicle traveling direction can be determined to be the left side. When the yaw angle is larger than -Ang2, the right side is determined so that the vehicle traveling direction can be determined as the right side. Indicates that no yaw angle has occurred. If it is determined in S55 that the yaw angle θ of the vehicle is greater than −Ang2, the yaw angle θ is greater than −Ang2 when the previous vehicle right side advance determination flag is ON. OFF (the vehicle is not traveling on the right side of the vehicle) is set (S57 in FIG. 6). On the other hand, if it is determined in S55 that the vehicle yaw angle θ is equal to or less than −Ang2, since the yaw angle θ is still equal to or less than −Ang2 when the previous vehicle right side advance determination flag is ON, the ECU 30 sets the vehicle right side advance flag to ON. (The vehicle is traveling on the right side of the lane) is set (S56 in FIG. 6).

  Then, the ECU 30 updates the vehicle right side progress flag (previous value) with the value of the vehicle right side progress flag set this time (S58 in FIG. 6).

  Subsequently, the ECU 30 determines whether or not the vehicle left side progress flag (previous value) = OFF (S59 in FIG. 7). If it is determined in S59 that the vehicle left-side advance flag (previous value) = OFF, the ECU 30 determines whether or not the yaw angle θ of the vehicle is greater than Ang1 (S60 in FIG. 7).

  When it is determined in S60 that the yaw angle θ is larger than Ang1, the ECU 30 increments the left side travel determination establishment timer (S61 in FIG. 7). On the other hand, when it is determined in S60 that the yaw angle θ is equal to or less than Ang1, the ECU 30 resets the left side travel determination establishment timer (S62 in FIG. 7). The left travel determination establishment timer is a timer for determining that the vehicle is traveling on the left side of the lane when the state where the yaw angle θ is greater than Ang1 continues to some extent when the previous vehicle left travel flag is OFF. As described above, since the yaw angle θ may be affected by camera noise, it is determined that the vehicle is traveling on the left side of the lane only when it is determined that the yaw angle θ is greater than Ang1 for a predetermined number of times.

  Then, the ECU 30 determines whether or not the left side progress determination establishment timer is greater than T2 (S63 in FIG. 7). If it is determined in S63 that the left side travel determination establishment timer is greater than T2, the state in which the yaw angle θ is greater than Ang1 has continued for a predetermined time when the previous vehicle left side travel determination flag is OFF. The flag is set to ON (the vehicle is traveling on the left side of the vehicle) (S65 in FIG. 7). On the other hand, if it is determined in S63 that the left side travel determination establishment timer is T2 or less, the state where the yaw angle θ is greater than Ang1 has not continued for a predetermined time when the previous vehicle left side travel determination flag is OFF. The vehicle left side progress flag is set to OFF (the vehicle is not traveling on the left side of the lane) (S66 in FIG. 7).

  On the other hand, when it is determined in S59 that the vehicle left side advance flag (previous value) = ON, the ECU 30 determines whether or not the yaw angle θ of the vehicle is smaller than Ang2 (S64 in FIG. 7). If it is determined in S64 that the yaw angle θ of the vehicle is smaller than Ang2, since the yaw angle θ is smaller than Ang2 when the previous vehicle left side traveling determination flag is ON, the ECU 30 turns OFF the vehicle left side traveling flag ( The vehicle is not traveling on the left side of the vehicle) (S66 in FIG. 7). On the other hand, if the yaw angle θ of the vehicle is determined to be equal to or greater than Ang2 in S64, the ECU 30 sets the vehicle left-side progress flag to ON (the vehicle left-side progress flag is ON) because the yaw angle θ is still greater than Ang2 when the previous vehicle left-side travel determination flag is ON. Is set on the left side of the lane) (S65 in FIG. 7).

  Then, the ECU 30 updates the vehicle left side progress flag (previous value) with the value of the vehicle left side progress flag set this time (S67 in FIG. 7).

  Next, the ECU 30 determines whether or not the driver right steering flag (previous value) = OFF at regular time intervals (S70 in FIG. 8). If it is determined in S70 that the driver right steering flag (previous value) = OFF, the ECU 30 determines whether or not the driver's steering torque is greater than MT1 (S71 in FIG. 8). MT1 (plus value) is a threshold value for determining whether the steering direction by the driver is the right direction or the left direction based on the steering torque by the driver. The steering torque has a positive value in the right direction and a negative value in the left direction. Therefore, when the steering torque is greater than MT1, a right steering torque is generated so that the driver's steering direction can be determined as the right direction. When the steering torque is smaller than −MT1, the driver's steering direction can be determined as the left direction. This indicates that a left steering torque is generated.

  If it is determined in S71 that the steering torque is greater than MT1, the ECU 30 increments the driver right steering determination establishment timer (S72 in FIG. 8). On the other hand, if it is determined in S71 that the steering torque is equal to or less than MT1, the ECU 30 resets the driver right steering determination establishment timer (S73 in FIG. 8). The driver right steering determination establishment timer is a timer for determining that the driver is steering in the right direction when the state where the steering torque is greater than MT1 continues to some extent when the previous driver right steering flag is OFF. Since the steering torque detected by the steering torque sensor 10 may include noise, it is determined that the driver is steering rightward only when it is determined that the steering torque is greater than MT1 for a predetermined number of times. To do.

  Then, the ECU 30 determines whether or not the driver right steering determination establishment timer is greater than T3 (S74 in FIG. 8). If it is determined in S74 that the driver right steering determination establishment timer is greater than T3, the ECU 30 maintains the driver right steering flag because the steering torque is greater than MT1 for a predetermined time when the previous driver right steering flag is OFF. Is set to ON (the driver is steering rightward) (S76 in FIG. 8). On the other hand, if it is determined in S74 that the driver right steering determination establishment timer is equal to or less than T3, since the steering torque is not greater than MT1 for a predetermined time when the previous driver right steering flag is OFF, the ECU 30 The right steering flag is set to OFF (the driver is not steering in the right direction) (S77 in FIG. 8). T3 is a threshold value for determining that the state where the steering torque is larger than MT1 (the state where the steering torque is smaller than -MT1) continues for a predetermined time.

  On the other hand, when it is determined in S70 that the driver right steering flag (previous value) = ON, the ECU 30 determines whether or not the steering torque by the driver is smaller than MT2 (S75 in FIG. 8). MT2 (plus value) is a threshold value for determining that the steering direction by the driver is not right or left by the steering torque by the driver, and is a value smaller than MT1. The steering torque has a positive value in the right direction and a negative value in the left direction. Therefore, when the steering torque is smaller than MT2, no right steering torque is generated so that the steering direction of the driver can be determined as the right direction. When larger than −MT2, the steering direction of the driver is determined as the left direction. It indicates that the leftward steering torque is not generated as much as possible. When it is determined in S75 that the steering torque of the driver is smaller than MT2, the steering torque becomes smaller than MT2 when the previous driver right steering flag is ON. Is not steered in the direction) (S77 in FIG. 8). On the other hand, if it is determined in S75 that the steering torque of the driver is equal to or greater than MT2, the steering torque is still equal to or greater than MT2 when the previous driver right steering flag is ON. Is being steered) (S76 in FIG. 8).

  Then, the ECU 30 updates the driver right steering flag (previous value) with the value of the driver right steering flag set this time (S78 in FIG. 8).

  Subsequently, the ECU 30 determines whether or not the driver left steering flag (previous value) = OFF (S79 in FIG. 9). When it is determined in S79 that the driver left steering flag (previous value) = OFF, the ECU 30 determines whether or not the driver's steering torque is smaller than -MT1 (S80 in FIG. 9).

  When it is determined in S80 that the steering torque is smaller than -MT1, the ECU 30 increments the driver left steering determination establishment timer (S81 in FIG. 9). On the other hand, if it is determined in S80 that the steering torque is equal to or greater than -MT1, the ECU 30 resets the driver left steering determination establishment timer (S82 in FIG. 9). The driver left steering determination establishment timer is a timer for determining that the driver is steering leftward when the state where the steering torque is smaller than −MT1 continues to some extent when the previous driver left steering flag is OFF. . As described above, noise may be included in the steering torque. Therefore, only when it is determined that the steering torque is smaller than −MT1 for a predetermined number of times, it is determined that the driver is steering leftward.

  Then, the ECU 30 determines whether or not the driver left steering determination establishment timer is greater than T3 (S83 in FIG. 9). If it is determined in S83 that the driver left steering determination establishment timer is greater than T3, the state in which the steering torque is smaller than -MT1 has continued for a predetermined time when the previous driver left steering flag is OFF. The flag is set to ON (the driver is steering leftward) (S85 in FIG. 9). On the other hand, if it is determined in S83 that the driver left steering determination establishment timer is equal to or less than T3, since the steering torque is less than -MT1 for a predetermined time when the previous driver left steering flag is OFF, the ECU 30 The driver left steering flag is set to OFF (the driver is not steering leftward) (S86 in FIG. 9).

  On the other hand, if it is determined in S79 that the driver left steering flag (previous value) = ON, the ECU 30 determines whether or not the steering torque by the driver is greater than −MT2 (S84 in FIG. 9). If it is determined in S84 that the driver's steering torque is greater than -MT2, the steering torque has become greater than -MT2 when the previous driver left steering flag is ON. Is not steered leftward) (S86 in FIG. 9). On the other hand, if it is determined in S84 that the driver's steering torque is -MT2 or less, since the steering torque is still -MT2 or less when the previous driver left steering flag is ON, the ECU 30 sets the driver left steering flag to ON (the driver is (S85 in FIG. 9) is set.

  Then, the ECU 30 updates the driver left steering flag (previous value) with the value of the driver left steering flag set this time (S87 in FIG. 9).

  Next, the ECU 30 determines whether or not the curve turning flag = ON at regular time intervals (S90 in FIG. 10). When it is determined in S90 that the curve turning flag is ON (that is, when the vehicle is turning in a curve), the ECU 30 determines whether or not the absolute value of the road curvature γ is larger than the maximum curvature in the curve (FIG. 10). S91). The maximum curvature in the curve indicates the maximum road curvature of the road while the vehicle is turning, and is updated every time the absolute value of the road curvature γ is larger than the maximum curvature in the curve set up to the previous time during the curve. Is done. When it is determined in S91 that the absolute value of the road curvature γ is larger than the maximum curvature in the curve, the ECU 30 updates the maximum curvature in the curve with the absolute value of the road curvature γ (S92 in FIG. 10). On the other hand, when it is determined in S91 that the absolute value of the road curvature γ is equal to or less than the maximum curvature in the curve, the ECU 30 holds the maximum curvature in the previous curve.

  The ECU 30 determines whether or not the curve exit vicinity flag (previous value) = OFF (S93 in FIG. 10). If it is determined in S93 that the curve exit vicinity flag is OFF, the ECU 30 resets the curve exit vicinity determination release timer (S94 in FIG. 10). Then, the ECU 30 determines whether or not the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve) (S95 in FIG. 10). Kr is a coefficient for determining whether or not the vehicle has reached the vicinity of the curve exit during a curve turn, and is a value smaller than 1. Kr is set such that the curve exit vicinity flag is turned on before the curve turning flag (small R curve turning flag) is turned off. Therefore, (Kr × maximum curvature in the curve) is smaller than the maximum curvature in the curve, and the vehicle exits the curve when the absolute value of the road curvature γ decreases from the maximum curvature in the curve to (Kr × maximum curvature in the curve). Indicates that you have reached the vicinity.

  When it is determined in S95 that the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve), the ECU 30 increments the curve exit vicinity determination establishment timer (S96 in FIG. 10). On the other hand, if it is determined in S95 that the absolute value of the road curvature is equal to or greater than (Kr × maximum curvature in the curve), the ECU 30 resets the curve exit vicinity determination establishment timer (S97 in FIG. 10). The curve exit vicinity determination establishment timer indicates that the vehicle has reached the vicinity of the curve exit when the absolute value of the road curvature γ is less than (Kr x maximum curvature in the curve) when the previous curve exit flag is OFF. It is a timer for determining. Since the road curvature γ may be affected by camera noise as described above, only when it is determined that the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve) for a predetermined number of times. It is determined that the vehicle is near the curve exit.

  Then, the ECU 30 determines whether or not the curve exit vicinity determination establishment timer is greater than T4 (S98 in FIG. 10). If it is determined in S98 that the curve exit vicinity determination establishment timer is greater than T4, the state where the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve) when the previous curve exit vicinity flag is OFF is the predetermined time. Since it has continued, the ECU 30 sets the curve exit vicinity flag to ON (the vehicle is in the vicinity of the curve exit) (S104 in FIG. 10). On the other hand, if the curve exit vicinity determination establishment timer is determined to be T4 or less in S98, the state where the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve) when the previous curve exit vicinity flag is OFF is predetermined. Since the time does not continue, the ECU 30 sets the curve exit vicinity flag to OFF (the vehicle is not near the curve exit) (S105 in FIG. 10). T4 is a threshold value for determining that the state where the absolute value of the road curvature γ is smaller than (Kr × maximum curvature in the curve) continues for a predetermined time.

  On the other hand, when it is determined in S93 that the curve exit vicinity flag is ON, the ECU 30 resets the curve exit vicinity determination establishment timer (S99 in FIG. 10). Then, the ECU 30 determines whether or not the absolute value of the road curvature γ is larger than (Kr × maximum curvature in the curve) (S100 in FIG. 10).

  When it is determined in S100 that the absolute value of the road curvature γ is larger than (Kr × maximum curvature in the curve), the ECU 30 increments the curve exit vicinity determination cancellation timer (S101 in FIG. 10). On the other hand, when it is determined in S100 that the absolute value of the road curvature γ is equal to or less than (Kr × maximum curvature in the curve), the ECU 30 resets the curve exit vicinity determination cancellation timer (S102 in FIG. 10). The curve exit vicinity determination release timer, when the previous curve exit neighborhood flag is ON, the vehicle reaches the vicinity of the curve exit when the absolute value of road curvature γ continues to some extent greater than (Kr x maximum curvature in the curve). It is a timer for determining that it has not been performed. Since the road curvature γ may be affected by camera noise as described above, only when it is determined that the absolute value of the road curvature γ is greater than (Kr × maximum curvature in the curve) for a predetermined number of times. It is determined that the vehicle is not near the curve exit.

  Then, the ECU 30 determines whether or not the curve exit vicinity determination cancellation timer is greater than T5 (S103 in FIG. 10). When it is determined in S103 that the curve exit vicinity determination cancellation timer is greater than T5, the state where the absolute value of the road curvature γ is greater than (Kr × maximum curvature in the curve) when the previous curve exit vicinity flag is ON is a predetermined time. Since it has continued, the ECU 30 sets the curve exit vicinity flag to OFF (the vehicle is not in the vicinity of the curve exit) (S105 in FIG. 10). On the other hand, if it is determined in S103 that the curve exit vicinity determination cancellation timer is T5 or less, the state where the absolute value of the road curvature γ is larger than (Kr × maximum curvature in the curve) when the previous curve exit vicinity flag is ON is predetermined. Since the time has not continued, the ECU 30 sets the curve exit vicinity flag to ON (the vehicle is in the vicinity of the curve exit) (S104 in FIG. 10). T5 is a threshold value for determining that the state where the absolute value of the road curvature γ is larger than (Kr × maximum curvature in the curve) continues for a predetermined time.

  On the other hand, when it is determined in S90 that the curve turning flag is OFF (that is, when the vehicle is traveling on a straight road), the ECU 30 resets the maximum curvature in the curve to 0 (S106 in FIG. 10) and determines the vicinity of the curve exit. The release timer is reset (S107 in FIG. 10), the curve exit vicinity determination establishment timer is reset (S108 in FIG. 10), and the curve exit vicinity flag is set to OFF (S109 in FIG. 10).

  Then, the ECU 30 updates the curve exit vicinity flag (previous value) with the value of the curve exit vicinity flag set this time (S110 in FIG. 10).

  Next, the ECU 30 determines whether the small R-curve turning flag (previous value) = ON and the small R-curve turning flag = OFF at regular intervals (that is, the current determination is a small R curve in the previous determination). Therefore, it is determined whether or not the vehicle has reached the exit of the small R curve (S120 in FIG. 11). If the determination condition of S120 is satisfied, the vehicle has reached the exit of the small R curve, and thus the ECU 30 sets the integral output reset flag to ON (S128 in FIG. 11).

  If the determination condition of S120 is not satisfied, the ECU 30 determines whether the small R curve turning flag = ON and the curve exit vicinity flag = ON (that is, whether the vehicle has reached the vicinity of the curve exit during the small R curve turning). Is determined (S121 in FIG. 11). When the determination condition of S120 is satisfied, the ECU 30 determines whether or not the driver is turning left based on the curve radius R, the driver left steering flag is OFF, and the integral value ID is less than 0 (that is, the driver is turning while the vehicle is turning left). Is not steered to the left and the direction of the additional torque by the lane keeping based on the integral value ID is determined to be the left) (S122 in FIG. 11). When the determination condition of S122 is satisfied, the ECU 30 reaches the vicinity of the curve exit during the small R curve turn in the left direction, the additional torque direction of the lane keep based on the integral value ID is leftward, and the driver is not steering left. Then, the integral output reset flag is set to ON (S128 in FIG. 11). On the other hand, if the determination condition of S122 is not satisfied, the ECU 30 determines whether the vehicle is turning right, the driver right steering flag is OFF, and the integrated value ID is greater than 0 based on the curve radius R (that is, the vehicle turns to the right curve). It is determined whether or not the driver is not steering rightward and the direction of the additional torque by the lane keeping based on the integral value ID is rightward) (S123 in FIG. 11). When the determination condition of S123 is satisfied, the ECU 30 reaches the vicinity of the curve exit during the small right turn of the right direction, the additional torque direction of the lane keep based on the integral value ID is the right direction, and the driver is not steering to the right. Then, the integral output reset flag is set to ON (S128 in FIG. 11).

  On the other hand, when the determination condition of S123 is not satisfied, the ECU 30 determines whether or not the curve turning flag (previous value) = ON and the curve turning flag = OFF (that is, the previous determination was a large R curve but the current determination). Since it is no longer a large R curve, it is determined whether or not the vehicle has reached the exit of the large R curve (S124 in FIG. 11). If the determination condition of S124 is satisfied, the ECU 30 determines whether or not the vehicle left side traveling flag = ON and the integral value ID is smaller than 0 (that is, both the vehicle traveling direction and the additional torque direction by lane keeping based on the integral value ID are left. Whether or not the direction is determined) is determined (S125 in FIG. 11). When the determination condition of S125 is satisfied, the ECU 30 reaches the curve exit during a large R-curve turn, and the direction in which the vehicle travels coincides with the direction of the additional torque by the lane keeping based on the integral value ID. The reset flag is set to ON (S128 in FIG. 11). On the other hand, when the determination condition of S125 is not satisfied, the ECU 30 determines whether or not the vehicle right side traveling flag = ON and the integral value ID is greater than 0 (that is, the direction of the additional torque by the lane keeping based on the vehicle traveling direction and the integral value ID). (S126 in FIG. 11). When the determination condition of S126 is satisfied, the vehicle reaches the curve exit during a large R curve turn, and the vehicle traveling direction and the additional torque direction by lane keeping based on the integral value ID coincide with each other in the right direction. The reset flag is set to ON (S128 in FIG. 11).

  If the determination condition of S124 is not satisfied, the curve exit or the vicinity of the curve exit is not reached when the curve is turning, or the curve is not turning, so the ECU 30 sets the integral output reset flag to OFF (FIG. 11). S127). If the determination condition of S126 is not satisfied, the vehicle has reached the exit of the large R curve, but the traveling direction of the vehicle does not match the additional torque direction by the lane keeping based on the integral value ID. The reset flag is set to OFF (S127 in FIG. 11).

Then, the F / F controller 31 of the ECU 30 calculates the yaw rate ω _γ by multiplying the multiplication value of the road curvature γ and the vehicle speed V by the gain K _γ at regular time intervals.

Further, the ECU 30 calculates a deviation Δθ = (θ ₀ −θ) between the yaw angle θ and the target yaw angle θ _0, and calculates the yaw rate ω _θ by multiplying the deviation Δθ by the gain K _θ .

Further, the ECU 30 calculates a deviation ΔD = (D ₀ −D) between the offset D and the target offset D ₀ . Then, the integrator 32 of the ECU 30 determines whether or not the integration output reset flag is ON (S130 in FIG. 12). When it is determined in S130 that the integration output reset flag is ON, the integrator 32 resets the integration value ID to 0 (S131 in FIG. 12). Here, in the case of a small R curve, the integral value ID is always reset to 0 at the curve exit, and in particular, the direction of the additional torque of the lane keep based on the integral value ID is in the curve inward direction and the driver is steered in the curve inward direction. When it is not, the integral value ID is reset to 0 as soon as the curve exit is approached. In the case of a large R curve, the integral value ID is basically not reset even at the curve exit, but the integral value ID is only obtained when the vehicle traveling direction and the direction of the additional lane keeping torque based on the integral value ID coincide at the curve exit. Is reset to zero. By these resets, unnecessary integral values disappear at or near the curve exit, and lane keeping torque based on the integral value is not added to the steering mechanism.

  On the other hand, when it is determined in S130 that the integration output reset flag is OFF, the integrator 32 time-integrates the deviation ΔD and calculates the integral value ID of the offset (S132 in FIG. 12).

Further, the ECU 30, multiplied by the gain _{K D} the deviation ΔD with multiplying the gain _{K ID} to the integral value ID, and calculates a yaw rate omega _D by adding the two multiplied values.

The ECU 30 calculates the target yaw rate ω by adding the three calculated yaw rates ω _γ , ω _D , and ω _θ . Then, the target lateral acceleration calculator 33 of the ECU 30 multiplies the target yaw rate ω by the vehicle speed V to calculate the target lateral acceleration G. Further, the output torque calculator 34 of the ECU 30 selects either the map TI at the time of increase or the map TR at the time of return based on the steering direction of the lane keep and the sign of the target lateral acceleration G, and refers to the selected map. An output torque T corresponding to the value of the target lateral acceleration G is extracted. Then, the ECU 30 transmits an output torque signal indicating the output torque T to the EPS ECU 41.

  The EPS ECU 41 receives the output torque signal, and multiplies the output torque indicated by the output torque signal by a predetermined coefficient. Then, the EPS ECU 41 adds the multiplication value (additional torque) to the assist torque, and drives and controls the motor 42 according to the assist torque + additional torque. The motor 42 generates a predetermined torque under the control of the ECPECU 41, and adds the torque to the steering mechanism. Then, an assist torque corresponding to the steering torque by the driver is applied to the steering mechanism, and an auxiliary additional torque for causing the vehicle to travel along the vehicle center is applied.

  FIG. 13 shows a case where the feedforward output becomes insufficient due to a small curve radius or a high vehicle speed, the offset OF1 occurs outside the lane of the vehicle, and the integral value outside the curve increases. In this case, since the lane keeping device 1 resets the integrated value when the vehicle reaches the curve exit or the vicinity of the curve exit, the torque in the curve inward direction based on the integral term is not added to the additional torque of the lane keep. Therefore, the travel locus ML1 of the vehicle becomes a locus along the center line of the lane even after passing the curve exit CC, and the vehicle is not involved in the curve.

  In FIG. 14, the slope of the low road surface cant is large inside the curve, a large lateral acceleration in the direction of the curve due to the road surface cant acts on the vehicle, an offset OF2 is generated inside the vehicle lane, and the integral value inside the curve is The case where it increases is shown. In this case, since the lane keeping device 1 resets the integrated value when the vehicle reaches the curve exit, the additional torque of the lane keep does not include the torque in the curve outward direction based on the integral term. Therefore, the travel locus ML2 of the vehicle is a locus along the center line of the lane even after passing the curve exit, and the lane departure of the vehicle does not occur.

  According to the lane keeping device 1, by resetting the integral value of the unnecessary offset at the curve exit or in the vicinity of the curve exit, unnecessary torque based on the integral value is not added to the additional torque by the lane keep. Therefore, in the lane keeping device 1, it is possible to add an appropriate lane keeping steering torque even at the curve exit, and it is possible to improve the accuracy of traveling the vehicle along the lane center.

  In particular, the lane keeping device 1 determines whether or not to reset the integral value by dividing into three at the curve exit of the small R curve, the vicinity of the curve exit, and the curve exit of the large R curve. Can be determined with high accuracy.

  When judging at the curve exit of a small R curve, the lane keep device 1 always resets the integral term, so even if the road surface cant steeply steep, lane departure does not occur, and even at a small curve radius and high vehicle speed, the curve is involved. It does not occur.

  When judging near the curve exit of the small R curve, the lane keeping device 1 only when the direction in which the additional torque based on the integrated value acts and the direction of the curve match and the driver is not steering in the curve direction. Since the timing of resetting the integral value is advanced, even if the curve radius is small, there is no incursion of the curve due to insufficient feedforward output. At this time, since the steering direction of the driver is also taken into consideration, the reset timing can be determined with high accuracy even when the road curvature γ is influenced by noise of the CCD camera 20 (captured image).

  When determining at the curve exit of the large R curve, the lane keeping device 1 resets the integrated value only when the direction in which the additional torque based on the integrated value acts and the traveling direction of the vehicle coincide with each other. The reset can be surely performed only when it is pushed further in the traveling direction by the additional torque based on it, and only the reset with high necessity can be performed.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is implemented in various forms, without being limited to the said embodiment.

  For example, although the present embodiment is applied to the lane keeping device, it can also be applied to other devices, for example, an automatic steering device.

  In this embodiment, the steering torque is applied by using the electric power steering device. However, the lane keeping device may be provided with an actuator that assists the rack and pinion. Therefore, the present invention can be applied to a vehicle that does not include a power steering device. Further, the present invention can be applied not only to an electric power steering device but also to a hydraulic power steering device, and may be configured to add steering torque by controlling an actuator that adjusts hydraulic pressure.

  In this embodiment, the lane keep control is performed by adding torque to the steering mechanism. However, the lane keep control may be performed by another parameter that can change the steering state such as the steering angle. Good.

  In the present embodiment, the lane is detected by recognizing a pair of white lines. However, the lane may be detected by recognizing other lines such as a yellow line other than the white line, or a road shoulder. Alternatively, the lane may be detected by another method such as detecting the lane by recognizing a block that partitions the lane and the sidewalk. Further, although the present embodiment is applied to a road having a lane, the present invention can also be applied to a road having no lane. In this case, it is necessary to detect the shoulder of the road.

  In the present embodiment, a lane (traveling road) is recognized based on an image captured by a camera, and a curve radius (road curvature), a vehicle yaw angle, and a vehicle offset are calculated based on the recognized lane. However, the road and these parameters may be obtained by other methods, for example, when detecting based on processing in the navigation system and map information, when detecting using various sensors, road-to-vehicle communication, etc. In some cases, information is obtained from outside the vehicle.

  In the present embodiment, the traveling direction of the vehicle is determined based on the yaw angle of the vehicle. However, the traveling direction of the vehicle is detected by other methods such as obtaining the traveling direction of the vehicle obtained by the navigation system. May be.

  In the present embodiment, the curve exit is determined based on the road curvature (curve radius). However, the curve exit may be determined by other methods such as acquiring current position information obtained by the navigation system. Good.

  In this embodiment, the integral reset control at the exit of the large R curve, the integral reset control at the exit of the small R curve, and the integral reset control near the exit of the small R curve are performed. It may be configured to perform only one control or two controls of the integral reset control.

  In this embodiment, the vicinity of the exit at the small R curve is determined using the driver steering direction. However, when the accuracy of information such as road curvature obtained based on the captured image is high (camera If the influence of noise is small), the determination may be made without using the steering direction of the driver.

It is a block diagram of the lane keeping apparatus which concerns on this Embodiment. FIG. 2 is a control block diagram of the lane keeping device of FIG. 1. 2 is a map of output torque with respect to target lateral acceleration in the lane keeping device of FIG. 1. It is a flowchart which shows the flow of the small R curve determination process in ECU of the lane keeping apparatus of FIG. It is a flowchart which shows the flow of the large R curve determination process in ECU of the lane keeping apparatus of FIG. It is a flowchart which shows the flow of the right side progress determination part of the vehicle advancing direction determination process in ECU of the lane keeping apparatus of FIG. It is a flowchart which shows the flow of the left side progress determination part of the vehicle advancing direction determination process in ECU of the lane keeping apparatus of FIG. 2 is a flowchart showing a flow of a right steering determination portion of a driver steering direction determination process in an ECU of the lane keeping device of FIG. 1. 3 is a flowchart showing a flow of a left steering determination portion of a driver steering direction determination process in the ECU of the lane keeping device of FIG. 1. It is a flowchart which shows the flow of the curve exit vicinity determination process in ECU of the lane keeping apparatus of FIG. It is a flowchart which shows the flow of the integral output reset determination process in ECU of the lane keeping apparatus of FIG. It is a flowchart which shows the flow of the integral output reset process in ECU of the lane keeping apparatus of FIG. It is an example of a driving | running locus | trajectory when not resetting the driving | running track | truck when resetting the integral value in case offset (integral value of offset) exists in the curve lane outside of a vehicle. FIG. 6 is an example of a travel locus when the integral value is reset and a travel locus when the reset is not performed when an offset (an integral value of the offset) exists inside the curve of the lane of the vehicle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Lane keeping device, 2 ... Steering wheel, 3 ... Steering shaft, 4 ... Steering gear box, 5 ... Rack bar, 6 ... Knuckle arm, 10 ... Steering torque sensor, 11 ... Vehicle speed sensor, 20 ... CCD camera, 21 ... Image processing unit, 30 ... ECU, 31 ... F / F controller, 32 ... integrator, 33 ... target lateral acceleration calculator, 34 ... output torque calculator, 40 ... electric power steering device, 41 ... EPSECU, 42 ... motor

Claims (7)

A travel path detecting means for detecting a travel path of the vehicle, a shift amount detecting means for detecting a shift amount from a predetermined position of the travel path of the vehicle, an integrating means for integrating the shift amount to obtain an integral term, And a calculation means for calculating a steering output for controlling the steering mechanism based on an amount of deviation from the predetermined position of the travel path and an integral term, and the steering mechanism so that the vehicle travels along the predetermined position of the travel path. In the steering device to be controlled,
A curve radius detecting means for detecting a curve radius of the road;
Curve exit judging means for judging whether or not the vehicle position is an exit of a curved road;
Vehicle traveling direction detection means for detecting the traveling direction of the vehicle,
When the vehicle exit is determined to be an exit of the curved road by the curve exit determining means while traveling on a curved road having a curve radius detected by the curve radius detecting means, the vehicle travel detected by the vehicle traveling direction detecting means. A steering device, wherein the integral term is reset when the direction and the steering control direction based on the integral term coincide.   The steering apparatus according to claim 1, wherein the vehicle traveling direction detection means detects the traveling direction based on an angle of the vehicle with respect to a traveling path.   The steering apparatus according to claim 1, wherein the curve exit determination unit determines based on a curve radius. A travel path detecting means for detecting a travel path of the vehicle, a shift amount detecting means for detecting a shift amount from a predetermined position of the travel path of the vehicle, an integrating means for integrating the shift amount to obtain an integral term, And a calculation means for calculating a steering output for controlling the steering mechanism based on an amount of deviation from the predetermined position of the travel path and an integral term, and the steering mechanism so that the vehicle travels along the predetermined position of the travel path. In the steering device to be controlled,
A curve radius detecting means for detecting a curve radius of the road;
A curve exit judging means for judging whether the vehicle position is an exit of a curved road,
Steering characterized in that the integral term is reset when the curve exit determining means determines that the vehicle position is the exit of the curve road while traveling on a curved road having a curve radius detected by the curve radius detecting means or less. apparatus. A travel path detecting means for detecting a travel path of the vehicle, a shift amount detecting means for detecting a shift amount from a predetermined position of the travel path of the vehicle, an integrating means for integrating the shift amount to obtain an integral term, And a calculation means for calculating a steering output for controlling the steering mechanism based on an amount of deviation from the predetermined position of the travel path and an integral term, and the steering mechanism so that the vehicle travels along the predetermined position of the travel path. In the steering device to be controlled,
A curve radius detecting means for detecting a curve radius of the road;
And a curve direction detecting means for detecting a direction in which a curved road is bent,
When the curve radius detected by the curve direction detection means coincides with the steering control direction based on the integral term while traveling on a curved road whose curve radius detected by the curve radius detection means is a predetermined radius or less, the integral term A steering device characterized in that the timing for resetting the vehicle is earlier than the timing based on the exit of the curved road. A steering direction detection means for detecting the steering direction by the driver;
6. The timing for resetting an integral term is advanced when a steering direction by a driver detected by the steering direction detection unit is different from a turning direction of a curved road detected by the curve direction detection unit. Steering device.   The steering apparatus according to claim 5 or 6, wherein the integral term is reset when approaching the exit of the curved road.

Images