Parking control device

Abstract

Provided is a parking control device that is capable of calculating the control amount, at the current position of a vehicle deviating from a parking path, of the steering angle of the vehicle based on the angle deviation, while taking into consideration an attitude angle of the vehicle which results in favorable reversion to the parking path. The present invention provides a parking control device that: generates a planned path which has a plurality of path segments; generates a target travel path for the current path segment on the basis of the current segment planned path; calculates a positional deviation and the tangential direction of the target travel path; calculates a target attitude angle of the vehicle at the current vehicle position on the basis of the positional deviation and the tangential direction; and calculates a target travel curvature of the vehicle such that the positional deviation and the attitude angle deviation of the current attitude angle of the vehicle with respect to the target attitude angle decrease.

Description

Parking Control Device

[0001] The present disclosure relates to a parking control device.

[0002] A known parking control device is the technology of Patent Document 1. In the technology of Patent Document 1, as shown in equations (13) to (15) of Patent Document 1 and in Figure 21A and the like, a target steering angle is calculated based on the curvature of the parking path, a first target steering angle correction amount is calculated based on the lateral deviation between the parking path and the host vehicle, and a second target steering angle correction amount is calculated based on the yaw angle deviation between the yaw angle of the parking path and the yaw angle of the host vehicle, thereby correcting the target steering angle based on the curvature.

[0003] Japanese Patent Application Laid-Open No. 2018-039293

[0004] However, in the technology of Patent Document 1, for example, when both the lateral deviation and the yaw angle deviation become large, the sum of the first and second target steering angle correction amounts becomes too large, which may cause overshooting with respect to the parking path and unstable convergence. On the other hand, if the gain multiplied by each deviation is reduced to prevent overshooting, the convergence to the parking path deteriorates. That is, in the technology of Patent Document 1, the control amount based on the angle deviation is calculated based on the yaw angle (tangential direction, attitude angle) of the parking path as a reference, and the yaw angle (attitude angle) of the host vehicle that will allow good convergence to the parking path at the current position of the host vehicle that has deviated from the parking path is not taken into consideration.

[0005] Therefore, the present disclosure aims to provide a parking control device that can calculate a control amount of the steering angle of the vehicle based on the angle deviation, taking into account the attitude angle of the vehicle at its current position that has deviated from the parking path, so that the vehicle will converge well onto the parking path.

[0006] The parking control device according to the present disclosure includes: a parking path planning unit that generates a planned path having a plurality of path sections from a control start position to a target parking position; a target path generation unit that determines a current route section, which is the route section that corresponds to the current vehicle position, and generates a target driving path for the current route section based on a current section planned path, which is the planned path for the current route section; and a target curvature calculation unit that calculates a position deviation of the current vehicle position with respect to the target driving path and a tangential direction of the target driving path, calculates a target attitude angle of the vehicle at the current vehicle position based on the position deviation and the tangential direction, and calculates a target driving curvature of the vehicle such that the attitude angle deviation of the current vehicle attitude angle with respect to the target attitude angle and the position deviation are reduced.

[0007] According to the parking control device disclosed herein, a tangent direction of a target driving path is calculated, a target attitude angle of the vehicle at the current vehicle position is calculated based on the position deviation and the tangent direction of the target driving path, and a target driving curvature of the vehicle is calculated so as to reduce the attitude angle deviation of the current vehicle attitude angle from the target attitude angle and the position deviation. Therefore, a target attitude angle of the vehicle at the current vehicle position deviating from the target driving path is taken into consideration, and a target driving curvature of the vehicle is calculated based on the attitude angle deviation. Even when both the position deviation and the attitude angle deviation become large, deterioration of convergence to the target driving path can be suppressed. Furthermore, even when a planned route with a complex shape including multiple route sections is generated, a target driving path for the current route section is generated based on the planned route of the current route section corresponding to the current vehicle position, and the target driving curvature is calculated. Therefore, even when a planned route with a complex shape is set, convergence to the planned route is improved, enabling clever parking.

[0008] 1 is a schematic configuration diagram of a parking control device according to Embodiment 1. FIG. 1 is a diagram for explaining the processing of a surrounding environment acquisition unit and a target parking position information setting unit, etc., according to Embodiment 1. FIG. 2 is a diagram for explaining a planned route in the case of parallel backward entry according to Embodiment 1. FIG. 3 is a diagram for explaining a planned route in the case of parallel forward entry according to Embodiment 1. FIG. 4 is a diagram for explaining a terminal section according to Embodiment 1. FIG. 5 is a diagram for explaining determination of a current route section according to Embodiment 1. FIG. 6 is a diagram for explaining the relationship between a current section planned route and a target driving route according to Embodiment 1. FIG. 7 is a diagram for explaining polynomial fitting according to Embodiment 1. FIG. 8 is a diagram for explaining calculation of a target attitude angle according to a position deviation and a position angle adjustment gain according to Embodiment 1. FIG. 9 is a diagram for explaining setting of a target attitude angle for each position according to Embodiment 1. FIG. 10 is a diagram for explaining a position angle adjustment gain according to Embodiment 1. FIG. 11 is a diagram for explaining a position curvature adjustment gain according to Embodiment 1. FIG. 12 is a diagram for explaining an attitude angle curvature adjustment gain according to Embodiment 1. FIG. 13 is a diagram for explaining convergence stability to a target driving route according to Embodiment 1. FIG. 14 is a diagram for explaining change in adjustment gain in the case of parallel forward entry according to Embodiment 1. FIG. 1 is a diagram for explaining a change in adjustment gain in the case of parallel backward entry according to embodiment 1. FIG. 2 is a diagram for explaining a change in adjustment gain in the case of parallel backward entry according to embodiment 1. FIG. 3 is a diagram for explaining a change in adjustment gain in the case of parallel backward entry according to embodiment 1. FIG. 4 is a diagram for explaining a change in adjustment gain depending on the outside or inside of the protruding direction of the target travel path according to embodiment 1. FIG. 5 is a flowchart for explaining the processing of the parking control device according to embodiment 1. FIG. 6 is a flowchart for explaining the processing of the target route generation unit and the target curvature calculation unit according to embodiment 1. FIG. 7 is a diagram for explaining a change in target travel curvature when entering a no-entry area according to embodiment 2. FIG. 8 is a flowchart for explaining the processing of the target route generation unit and the target curvature calculation unit according to embodiment 2. FIG. 9 is a flowchart for explaining the hardware configuration of the parking control device according to embodiments 1 and 2.

[0009] 1. First Embodiment A parking control device 300 according to the first embodiment will be described with reference to the drawings. Fig. 1 is a schematic block diagram of the parking control device 300 according to the first embodiment.

[0010] The parking control device 300 includes a surrounding environment acquisition unit 100, a target parking position information setting unit 110, a vehicle information acquisition unit 120, a no-travel area generation unit 130, a parking path planning unit 140, a target path generation unit 150, a target curvature calculation unit 160, and a steering control unit 170. The vehicle is equipped with an electric steering device 180. The electric steering device 180 is a device that changes the steering angle of the wheels by the driving force of an electric motor.

[0011] 1-1. Surrounding Environment Acquisition Unit 100 The surrounding environment acquisition unit 100 acquires the corner position of the parking space and the aisle boundary as shown in FIG. 2 using detection information from one or more distance measurement sensors such as a camera (a surrounding monitoring camera including a monocular camera and a stereo camera), a millimeter-wave radar, a laser radar, and a sonar sensor. For example, in the case of a sonar sensor, the sonar sensor acquires the distance between the host vehicle and another vehicle considered to be an obstacle, and the distance between the host vehicle and an obstacle on the opposite side of the other vehicle, and acquires the corner position of the other vehicle as the corner position of the parking space, and the position to the obstacle on the opposite side of the other vehicle as the aisle boundary. The origin when calculating the corner position of the parking space and the aisle boundary is, for example, the position at the start of parking as shown in FIG. 2, and the direction in which the host vehicle moves forward from the parking start point toward the parking space is the X-axis direction, and the vehicle width direction is the Y-axis direction (the origin position may be any position). In addition, with regard to the x and y coordinates of the current section planned route, the target driving route, and the vehicle position, which will be described later, the positions (x0, y0) of the start points of the current section planned route and the target driving route become the origin (0, 0), and translation coordinate transformation and rotation coordinate transformation are performed on the X and Y coordinates in FIG. 2 so that the x-axis direction after transformation corresponds to the direction of the attitude angle of the start point of the current section planned route.

[0012] 1-2. Target parking position information setting unit 110 The target parking position information setting unit 110 sets a target parking position and a target parking posture angle for parking the vehicle as shown in Fig. 2 based on the corner position of the parking space and the aisle boundary acquired by the surrounding environment acquisition unit 100. The origin of the target parking position is the same as that of the surrounding environment recognition.

[0013] 1-3. Vehicle information acquisition unit 120 The vehicle information acquisition unit 120 acquires the current vehicle position and current vehicle attitude angle at the center of the rear axle of the vehicle using detection information from a wheel speed sensor, a yaw rate sensor, etc. The current vehicle position and current vehicle attitude angle are calculated, for example, based on the vehicle's travel distance per unit time calculated from the wheel speed measured by the wheel speed sensor and the change in attitude angle per unit time of the vehicle calculated from the vehicle's yaw rate measured by the yaw rate sensor, with the parking start point shown in FIG. 2 as the reference point.

[0014] 1-4. Travel-prohibited area generation unit 130 The travel-prohibited area generation unit 130 sets a travel-prohibited area based on the corner positions of the parking space and the aisle boundaries acquired by the surrounding environment acquisition unit 100. The travel-prohibited area indicates an area in which the host vehicle cannot travel when parking, as shown in Fig. 2. The travel-prohibited area generation unit 130 generates the area outside the detection range of the sensor used in the surrounding environment acquisition unit 100 as a travel-prohibited area.

[0015] 1-5. Steering Control Unit 170 The steering control unit 170 controls the target traveling curvature ρ calculated by the target curvature calculation unit 160 (described later). * Based on this, the target steering angle δ * and calculate the target steering angle δ * The steering angle of the vehicle is controlled based on the target driving curvature ρ * is the target curvature of the travel path of the host vehicle. The steering control unit 170 calculates the actual steering angle when the actual steering angle is smaller than the target steering angle δ * Here, the vehicle's running curvature ρ, turning radius r, and steering angle δ (tire angle) have the relationship shown in Equation (1) (Source: Tokyo Denki University Press, Masato Abe, Automobile Dynamics and Control, 2nd Edition).

[0016] Here, V is the vehicle speed, A is the vehicle stability factor, and 1 is the vehicle wheelbase. Using the relationship in equation (1), the target running curvature ρ * Based on this, the target steering angle δ *The current vehicle speed may be used, but during parking control, the vehicle speed V is generally within a low predetermined range. 2 may be a constant. During parking control, the host vehicle is controlled to travel at a slow speed.

[0017] 1-6. Parking Path Planning Unit 140 The parking path planning unit 140 generates a planned path from the control start position to the target parking position, including multiple route sections. Specifically, the parking path planning unit 140 generates a planned path for the host vehicle to travel from the control start position to the target parking position, based on the corner positions of the parking space acquired by the surrounding environment acquisition unit 100, the aisle boundaries, the target parking position and target parking attitude angle set by the target parking position information setting unit 110, the current host vehicle position and current host vehicle attitude angle acquired by the host vehicle information acquisition unit 120, and the no-travel area generated by the no-travel area generation unit 130. Specifically, the parking path planning unit 140 sets multiple discrete waypoints from the control start position to the target parking position, sets a section between two adjacent waypoints along the planned path as a route section, and sets the position, attitude angle, curvature, curvature change rate, and traveling direction of the host vehicle at each waypoint, as well as the route shape (straight line, clothoid curve, or circular arc) of each route section. When the planned route is regenerated, the control start position may be reset to correspond to the current vehicle position. Various known methods are used to generate the planned route.

[0018] The target route generation unit 150 determines a current route section, which is a route section corresponding to the current vehicle position, and generates a target driving route for the current route section based on the current section planned route, which is a planned route for the current route section. The target curvature calculation unit 160 calculates a target driving curvature ρ of the vehicle using the target driving route. * The details of these processes will be described later.

[0019] 3A to 3C show examples of planned routes for parallel parking, backward parallel parking, and forward parallel parking, respectively. The parking path planning unit 140 sets the position, attitude angle, curvature, curvature change rate, and traveling direction of the vehicle at each waypoint from the control start position S1 to the target parking position. The parking path planning unit 140 also sets the route shape (straight line, clothoid curve, circular arc) of each route section, and generates section planned routes, which are planned routes for each route section. The parking path planning unit 140 generates the curved section planned route using at least a clothoid curve or a circular arc.

[0020] As shown in Figures 3A to 3C, based on the position, curvature, and curvature change rate at each waypoint, the route shape of a route section where the curvature is a constant value is set to an arc, the route shape of a route section where the curvature changes at a constant rate is set to a clothoid curve, and the route shape of a route section where the curvature is 0 is set to a straight line.

[0021] The x- and y-coordinate positions of each point s from the start point to the end point of each section planned route are expressed as equations (2) and (3) in the case of a clothoid curve, and as equations (4), (5), and (6) in the case of a circular arc. The center positions xc and yc of the circular arc are expressed as equations (7) and (8). Here, point s is expressed as the travel distance from the start point on the planned route.

[0022] In equations (2) to (8), ρ0 is the curvature at the start point of the planned section route, ρ(s) is the curvature at each point s of the planned section route, ν is the curvature change rate of the planned section route, γ0 is the attitude angle at the start point of the planned section route, γ(s) is the attitude angle at each point s of the planned section route, x0, y0 are the positions of the start point of the planned section route, and sgn(v x) is a sign function that outputs a sign indicating the forward or backward traveling direction of the vehicle (forward: +1, backward: -1), sgn(ν) is a sign function that outputs a sign indicating the direction of change in the curvature change rate ν (if the curvature change rate is positive: +1, if the curvature change rate is negative: -1), C(·) and S(·) are Fresnel integrals expressed by equations (9) and (10), and r is the radius of curvature. In addition, in order to generate a target traveling route for the current route section, which will be described later, the position (x 0, y) is set to the origin (0,0), and a rotational coordinate transformation is performed using cos(γ...) and sin(γ...) so that the x-axis direction of the current section planned route corresponds to the direction of the attitude angle γ at the start point of the current section planned route.

[0023]

[0024] 4, the route section immediately before the target parking position is defined as the terminal section. The terminal section is determined by the positional relationship between the target parking position and the corner position of the parking space. If the target parking position and the corner position of the parking space are far from each other, the distance from the vehicle entering the parking space to the target parking position is long, so the terminal section is long. Conversely, if the target parking position and the corner position of the parking space are close, the distance from the vehicle entering the parking space to the target parking position is short, so the terminal section is short.

[0025] As a method for generating a planned route, for example, the method of Japanese Patent No. 7267384 is used. Specifically, a virtual exit route (a route consisting of a travel distance and a curvature as shown in FIGS. 3A to 3C) from the target parking position to the control start position is generated, constraints such as not interfering with the aisle boundary and the corner position of the parking space are set for the generated exit route, an evaluation function consisting of a steering angle, a steering speed, a traveling distance, and a time required to reach the target parking position is applied, and a route that minimizes the evaluation function while satisfying the constraints is generated as the planned route.

[0026] 1-7. Target Route Generator 150 The target route generator 150 determines a current route section, which is a route section corresponding to the current vehicle position. For example, the target route generator 150 determines two consecutive waypoints that are closest to the current vehicle position, and determines the route section between the two determined waypoints as the current route section. Alternatively, the target route generator 150 may determine two consecutive waypoints whose positions and attitude angles are closest to the current vehicle position and current vehicle attitude angle, and determine the route section between the two determined waypoints as the current route section. In this case, two consecutive waypoints that are located ahead of one of the waypoints in the traveling direction of the vehicle may be determined.

[0027] An example of determining the current route section for parallel parking is shown in Figure 5. In Figure 5, the current vehicle position is closest to two consecutive waypoints S2 and S3, and waypoint S3 is located ahead of the vehicle in the direction of travel, so the route section between the two waypoints S2 and S3 is determined to be the current route section.

[0028] The target route generation unit 150 generates a target driving route for the current route section based on the current section planned route, which is the planned route for the current route section. The target route generation unit 150 generates a target driving route every time the current section planned route changes. Figure 6 shows a relationship between the current section planned route and the target driving route.

[0029] When the current section planned route is a curve, for example, a clothoid curve, since it includes a special function of the Fresnel integral as shown in Equations (2) and (3), it cannot be expressed as a function of f(x, y), and the target attitude angle and target traveling curvature cannot be calculated in the target curvature calculation unit 160. Therefore, when the current section planned route is a curve, the target route generation unit 150 generates a target traveling route by approximating the current section planned route to a polynomial curve.

[0030] On the other hand, when the current section planned route is a straight line, the target route generation unit 150 generates, as the target driving route, a straight line that passes through the start point and end point of the current section planned route. For example, as shown in equation (11-1), the target route generation unit 150 generates, as the target driving route f(x, y), a straight line that passes through the position x0, y0 of the start point of the current section planned route and has an attitude angle γ0 of the start point of the current section planned route. In this embodiment, a target driving route f(x, y) of equation (11-2) is used, which is obtained by performing a translation coordinate transformation and a rotation coordinate transformation on equation (11-1) so that the positions (x0, y0) of the start points of the current section planned route and the target driving route become the origin (0, 0) and the x-axis direction coincides with the direction of the attitude angle γ0 of the start point of the current section planned route. The x and y at which f(x, y) = 0 are the positions of the target driving route.

[0031] If the planned route for the current section is a curve, the target route generating unit 150 generates a target driving route by approximating the planned route for the current section to a polynomial curve using polynomial fitting or Taylor expansion.

[0032] A case where polynomial fitting is used will be described. FIG. 7 shows an example of polynomial fitting of the current section planned route (clothoid curve) of the current route section S2 to S3 in the tandem storage shown in FIG. 3A and FIG. 5. First, as shown in FIG. 7, the current section planned route is divided into N equal parts, and the positions of each of the N divided points are calculated to create a point cloud. The position of each point is calculated using equations (2) and (3). Then, coefficients of each degree of the polynomial that is optimal for the point cloud in a least-squares sense are calculated. For example, when a third-order polynomial is calculated, x is calculated as shown in equation (12). 3 , x 2 , x 1 , x 0 Coefficients a3, a2, a1, and a0 for the terms of each degree are calculated. The position (x0, y0) of the start point of the target travel path f(x, y) is set to the origin (0, 0). The x and y where f(x, y) = 0 are the positions of the target travel path. The degree of the polynomial curve may be any degree greater than or equal to second.

[0033] Note that the current section planned route may be short. In this case, if the degree of the polynomial curve is high, a large number of points are required for accurate approximation, resulting in low approximation accuracy. Therefore, when the current section planned route is curved, the target route generation unit 150 may decrease the degree of the polynomial curve as the length of the current section planned route becomes shorter. For example, when the length of the current section planned route, which is a curve, is equal to or greater than the judgment length, the target route generation unit 150 sets the degree of the polynomial curve to 3, and when the length of the current section planned route is less than the judgment length, the target route generation unit 150 sets the degree of the polynomial curve to 2.

[0034] Even when the route shape of the current section planned route is an arc, the target driving route f(x, y) can be expressed as a polynomial curve by calculating the positions of each point obtained by dividing the current section planned route into N equal parts using equations (4) to (6), as in the case of a clothoid curve, and calculating the polynomial coefficients.

[0035] A case where Taylor expansion is used will be described. In the case of a clothoid curve, the Fresnel integral parts of C(·) and S(·) described in equations (2) and (3) are expanded into polynomials by Taylor expansion. For example, if x0 and y0 in equations (2) and (3) are converted to 0 and the Fresnel integral parts are Taylor expanded to the lowest degree whose coefficients are not 0, equations (2) and (3) can be expanded into linear and cubic equations such as equations (13) and (14). Then, using equations (13) and (14), the target travel path f(x, y) corresponding to the current section planned route of the clothoid curve can be expressed by a cubic polynomial curve such as equation (15). The starting position (x0, y0) of the target travel path f(x, y) is set to the origin (0, 0). The x and y values ​​at which f(x, y) = 0 are the positions of the target travel path.

[0036] When the route shape of the current section planned route is a circular arc, it can be approximated to a polynomial curve by performing Taylor expansion, just like a clothoid curve. In the case of a circular arc, the target travel route f(x, y) is expressed by equation (16), which includes a root sign. Therefore, by using terms up to the second degree of Taylor expansion for the root sign, the target travel route f(x, y) can be expressed by a fourth-order polynomial curve such as equation (17). In equations (16) and (17), sgn(v x r) is based on the sign of the vehicle's direction of travel (forward: +1, backward: -1) and the sign of the curvature radius (counterclockwise turning: +1, clockwise turning: -1). If the signs are the same, sgn(v x r) = 1, and in the case of different signs, sgn(v x r) = -1. The starting position (x0, y0) of the target travel path f(x, y) is set to the origin (0, 0). The x and y where f(x, y) = 0 are the positions of the target travel path.

[0037] In this embodiment, the clothoid curve and the circular arc are approximated to third-order and fourth-order polynomial curves, respectively, using Taylor expansion, but any degree greater than or equal to two may be used.

[0038] 1-8. Target curvature calculation unit 160 The target curvature calculation unit 160 calculates the position deviation e1 of the current vehicle position with respect to the target driving route and the tangent direction γ of the target driving route. † Calculate the position deviation e1 and the tangential direction γ † Based on this, the target attitude angle γ of the host vehicle at the current host vehicle position is calculated. * Calculate the target attitude angle γ * The current vehicle attitude angle γ ego The target driving curvature ρ of the vehicle is set so that the attitude angle deviation e2 and the position deviation e1 of the vehicle are reduced. * Calculate the following.

[0039] In this embodiment, when the current section planned route is a curve, the target curvature calculation unit 160 calculates the position deviation e and the tangent direction γ using a target travel route f(x, y) of a polynomial curve that approximates the current section planned route. †When the current section planned route is a straight line, the target curvature calculation unit 160 calculates the position deviation e and the tangential direction γ using the straight line target travel route f(x, y) representing the current section planned route. † Calculate the following.

[0040] < Target attitude angle γ of the own vehicle * > Calculation of target attitude angle γ of the vehicle at the current vehicle position * As the position error e approaches 0, the target attitude angle γ * is the tangent direction γ of the target travel path † For example, equations (18) to (20) are used. † In equation (19) that calculates ∂ x f(x, y), ∂ y f(x, y) indicate the first partial differentials of the target driving path f(x, y) with respect to x and y, respectively. Arctan2(·) is a known function that can also be expressed as atan2(·). Here, x and y in equation (19) are used to represent the position of the target driving path that corresponds to the current vehicle position (for example, the position used to calculate the position deviation e1 or the position closest to the vehicle position). Here, the tangential direction γ † is the target attitude angle γ * In the equation (20) for calculating the position deviation e1, the target traveling path f(x, y) is the tangent direction of the current vehicle position x on the x-axis and the y-axis. ego , y ego is substituted. ego , y egoare coordinate-transformed to match the x, y coordinates of the target driving route. The position deviation e1 calculated by equation (20) is the position deviation of the current vehicle position in the y-axis direction with respect to the target driving route. Note that the position deviation e1 may also be calculated as the shortest distance, a position deviation in the normal direction of the target driving route, or the like. Note that in this embodiment, for the target driving route f(x, y) in equations (19) and (20), equation (11) is used if the current section planned route is a straight line, equation (12) or equation (15) is used if the current section planned route is a clothoid curve, and equation (12) or equation (17) is used if the current section planned route is a circular arc.

[0041]

[0042] Target attitude angle γ of the vehicle * In equation (18) that calculates the above equation, K1 is a position angle adjustment gain, which is an adjustment gain that adjusts the amount of change in the tilt angle of the target attitude angle relative to the position error e1. K1 is set to a positive value. The position error e1 is multiplied by the position angle adjustment gain K1. As shown in FIG. 8, as K1e1 increases or decreases from 0, a sin(tanh(K1e1)) increases or decreases from 0 and asymptotically approaches +π / 2 or -π / 2. Any function of any shape may be used as long as it has a similar tendency. The tangential direction γ † From sgn(v x ) asin(tanh(K1e1)) is subtracted, and the target attitude angle γ * is calculated. x ) is a sign function (forward: +1, backward: -1) according to the traveling direction of the vehicle.

[0043] FIG. 9 shows the target attitude angle γ when the vehicle is assumed to be at each position. * are indicated by arrows (vectors). That is, each arrow represents the target attitude angle γ * 9, as the absolute value of the position deviation e1 increases, the tangential direction γ of the target travel route increases. †The target attitude angle γ * 8 and 10, by increasing or decreasing the position angle adjustment gain K1, it is possible to adjust the gain (degree) of increase or decrease in the absolute value of the tilt angle relative to the increase or decrease in the absolute value of the position error e1. In other words, by increasing the position angle adjustment gain K1, it is possible to adjust the gain (degree) of increase or decrease in the absolute value of the target attitude angle γ * On the other hand, by reducing the position angle adjustment gain K1, the target attitude angle γ can be increased for the same absolute value of the position deviation e1. * The absolute value of the tilt angle can be reduced, and the convergence to the target driving path can be made gentler.

[0044] By using equations (18) to (20), the derivative of the Lyapunov function candidate V expressed by equation (21) with respect to the moving distance s becomes negative, and if the robot travels for a sufficiently long time, the position error e converges to 0. Therefore, due to the stability of the Lyapunov function, the target attitude angle γ can be calculated from equation (20). * Calculate the target attitude angle γ * It is guaranteed that the vehicle traveling along the route will stably converge to the target route.

[0045] <Target driving curvature of the own vehicle ρ * The target curvature calculation unit 160 calculates the target attitude angle γ of the host vehicle. * The current vehicle attitude angle γ ego The target driving curvature ρ of the vehicle is set so that the attitude angle deviation e2 and the position deviation e1 of the vehicle are reduced. * Calculate the following.

[0046] In this embodiment, the following equations (22) to (25) are used: * In the equation (22) that calculates the target attitude angle γ of the vehicle, the first term on the right side is * The value dγ obtained by differentiating * / ds, and the target attitude angle γ *is the basic value of the target traveling curvature based on the rate of change of the position deviation e1. The second term on the right-hand side is the component of the target traveling curvature that reduces the position deviation e1, and the position deviation e1 is multiplied by the position curvature adjustment gain K2. The position curvature adjustment gain K2 is an adjustment gain that adjusts the amount of change in the target traveling curvature relative to the position deviation e1. K2 is set to a positive value. The third term on the right-hand side is the component of the target traveling curvature that reduces the attitude angle deviation e2, and the attitude angle deviation e2 is multiplied by the attitude angle curvature adjustment gain K3. The attitude angle curvature adjustment gain K3 is an adjustment gain that adjusts the amount of change in the target traveling curvature relative to the attitude angle deviation e2. K3 is set to a positive value.

[0047] As shown in FIG. 11 , by increasing the position curvature adjustment gain K2, the absolute value of the component of the target curvature corresponding to the position deviation e1 can be increased for the same absolute value of the position deviation e1, thereby accelerating convergence to the target travel path. On the other hand, by decreasing the position curvature adjustment gain K2, the absolute value of the component of the target curvature corresponding to the position deviation e1 can be decreased for the same absolute value of the position deviation e1, thereby accelerating convergence to the target travel path. Also, as shown in FIG. 12 , by increasing the attitude angle curvature adjustment gain K3, the absolute value of the component of the target curvature corresponding to the attitude angle deviation e2 can be increased for the same absolute value of the attitude angle deviation e2, thereby accelerating convergence to the target travel path. On the other hand, by decreasing the attitude angle curvature adjustment gain K3, the absolute value of the component of the target curvature corresponding to the attitude angle deviation e2 can be decreased for the same absolute value of the attitude angle deviation e2, thereby accelerating convergence to the target travel path.

[0048]

[0049] In equation (22), ∇f(x ego , y ego ) is the gradient of the target driving path f(x, y) in vector analysis, and the current vehicle position x ego , y egois substituted. sinc(·) is a known Zinc function, and as the absolute value of the attitude angle error e2 increases from 0, the output value of the function decreases from 1 toward 0. In other words, as the absolute value of the attitude angle error e2 increases, the absolute value of the component of the second term on the right side of equation (22) decreases. Equation (23) is an equation obtained by differentiating equation (18) with respect to the travel distance s. Equation (24) is an equation obtained by differentiating equation (19) with respect to the travel distance s. In equation (24), ∂ x f, ∂ xx f, ∂ yx f, ∂ y f, ∂ yy f denotes the first and second partial differentials of the target driving path f(x, y) with respect to x and y, respectively. As in equation (19), the position of the target driving path corresponding to the current vehicle position is used for x and y of each first and second partial differential of the target driving path f(x, y).

[0050] 13, by using equations (22) to (25), the derivative of the Lyapunov function candidate V expressed by equation (26) with respect to the travel distance s becomes negative, and if the vehicle travels for a sufficiently long time, the position error e and attitude angle error e included in V converge to 0. Therefore, due to the stability of the Lyapunov function, the target travel curvature ρ can be calculated from equation (22). * Calculate the target driving curvature ρ * It is guaranteed that the vehicle traveling along the target travel path will stably converge to the target travel path. Here, w in equation (26) is a weight gain.

[0051] <Changes in each adjustment gain> The target curvature calculation unit 160 changes one or more of the position angle adjustment gain K1, which is an adjustment gain that adjusts the amount of change in the tilt angle of the target attitude angle relative to the position deviation e1, the position curvature adjustment gain K2, which is an adjustment gain that adjusts the amount of change in the target running curvature relative to the position deviation e1, and the attitude angle curvature adjustment gain K3, which is an adjustment gain that adjusts the amount of change in the target running curvature relative to the attitude angle deviation e2.

[0052] According to this configuration, each adjustment gain can be appropriately changed depending on the situation, thereby enabling the vehicle to converge favorably on the target driving route.

[0053] <Changing Each Adjustment Gain According to the Type of Parking Method> In this embodiment, the target curvature calculation unit 160 changes one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 according to the type of parking method. For example, the types of parking methods include parallel backward entry, parallel backward entry, parallel forward entry, parallel forward exit, parallel backward exit, and parallel forward exit. The types of parking methods are set by combining parallel or parallel, forward or backward, entry or exit, and whether or not a turn is required. Alternatively, the type of parking method may be set for each typical pattern of the planned route.

[0054] The position angle adjustment gain K1, position curvature adjustment gain K2, and attitude angle curvature adjustment gain K3, which have been adjusted in advance for each type of parking method through simulation and actual vehicle evaluation, etc., based on the driving constraints of each vehicle (maximum vehicle speed, maximum steering speed, maximum steering angle, etc.), are stored in advance in a storage device such as a ROM for each type of parking method, and the target curvature calculation unit 160 reads out and sets the position angle adjustment gain K1, position curvature adjustment gain K2, and attitude angle curvature adjustment gain K3 that correspond to the current type of parking method.

[0055] According to this configuration, it is possible to set the optimum adjustment gains for each type of parking method, thereby enabling the vehicle to converge favorably on the target driving path.

[0056] <Changes in each adjustment gain before and after a turning point> Furthermore, when the current route section is one or more specific route sections that are set to include a turning point, the target curvature calculation unit 160 changes one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3.

[0057] Before and after the turning point, the attitude angle of the planned route changes significantly, and forward and reverse directions are switched, so the position deviation e1 and attitude angle deviation e2 are likely to become large, resulting in a special state different from other states. According to the above configuration, one or more of the three adjustment gains are changed in a specific route section that includes a turning point, so even if the position deviation e1 and attitude angle deviation e2 become large before and after the turning point, it is possible to ensure good convergence of the host vehicle to the target driving route.

[0058] The specific route section including the turning point may be set for each type of parking method (for example, parallel backward entry, parallel backward entry, parallel forward entry, parallel forward exit, parallel backward exit, and parallel forward exit). Also, the set value of each adjustment gain for the specific route section may be set for each type of parking method.

[0059] For example, in the case of a parallel reverse parking entry, the route section S7 to S9 in Fig. 3A before the final turning point is set as a specific route section, and one or more of the three adjustment gains are changed between the specific route section and other route sections. In the case of a parallel reverse parking entry, the route section S6 to S9 in Fig. 3B before the final turning point is set as a specific route section, and one or more of the three adjustment gains are changed between the specific route section and other route sections. In the case of a parallel forward parking entry, the route section S6 to S10 in Fig. 3C after the final turning point is set as a specific route section, and one or more of the three adjustment gains are changed between the specific route section and other route sections.

[0060] For example, in the case of parallel forward parking, as shown on the left side of FIG. 14, in the route section from the final turning point to the target parking position (corresponding to S6 to S10 in FIG. 3C), if the current position of the vehicle is far from the target driving route, if the position angle adjustment gain K1 is large, the target attitude angle γ * 14, the absolute value of the tilt angle of the vehicle becomes large, and the vehicle may overshoot the target driving route and take a bulging trajectory. Therefore, as shown on the right side of Fig. 14, in this specific route section, the position angle adjustment gain K1 is set smaller than in route sections other than the specific route section (for example, the reference value), and the target attitude angle γ of the vehicle is set smaller. * By reducing the absolute value of the tilt angle, it is possible to suppress overshooting of the host vehicle relative to the target driving route, and to allow the host vehicle to smoothly follow the target driving route.

[0061] In the case of parallel backward parking, if the attitude angle of the host vehicle cannot follow the attitude angle of the target driving route in the route section before the final turning point before entering the parking space (corresponding to S7 to S9 in FIG. 3A), as shown in FIG. 15, even if the vehicle is steered in the route section from the turning point to the target parking position, the position and attitude angle of the host vehicle may not sufficiently reach the position and attitude angle of the target parking position. Therefore, as shown in FIG. 16, in a specific route section before the final turning point, the attitude angle curvature adjustment gain K3 is set larger than in route sections other than the specific route section (for example, a reference value), and the attitude angle deviation e2 is preferentially reduced. This reduces the attitude angle deviation e2 at the turning point, and reduces the deviation of the attitude angle of the host vehicle at the target parking position. Furthermore, even if the position deviation e1 becomes large to some extent at the turning point, the attitude angle deviation e2 can be reduced and the attitude angle of the vehicle is set to an angle that makes it easy to move toward the target parking position, so that the attitude angle of the vehicle can be changed so that it moves toward the target parking position in the route section from the turning point toward the target parking position, thereby reducing deviation of the vehicle's position at the target parking position.

[0062] 17 shows the behavior of the route section (corresponding to S6 to S9 in FIG. 3B ) before the final turning point before entering the parking space in the case of parallel backward parking. If the attitude angle of the host vehicle cannot track the attitude angle of the target driving route, even if steering is performed in the route section from the turning point to the target parking position, the position and attitude angle of the host vehicle may not sufficiently reach the position and attitude angle of the target parking position (not shown). Therefore, as shown in FIG. 17 , in a specific route section before the final turning point, the attitude angle curvature adjustment gain K3 is set larger than in route sections other than the specific route section (e.g., a reference value), and the attitude angle deviation e2 is preferentially reduced. This reduces the attitude angle deviation e2 at the turning point, thereby reducing the deviation of the attitude angle of the host vehicle at the target parking position. Furthermore, even if the position deviation e1 becomes large to some extent at the turning point, the attitude angle deviation e2 can be reduced and the attitude angle of the vehicle is set to an angle that makes it easy to move toward the target parking position, so that the attitude angle of the vehicle can be changed so that it moves toward the target parking position in the route section from the turning point toward the target parking position, thereby reducing deviation of the vehicle's position at the target parking position.

[0063] <Changing Adjustment Gains According to Each Deviation> Furthermore, the target curvature calculation unit 160 may change one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 based on the position deviation e1 and the attitude angle deviation e2.

[0064] According to this configuration, by changing the adjustment gain based on the position deviation e1 and the attitude angle deviation e2, it is possible to optimize the convergence to the target travel path.

[0065] For example, when the absolute value of the attitude angle deviation e2 is equal to or greater than the determination value of the attitude angle deviation and the absolute value of the position deviation e1 is less than the determination value of the position deviation, the target curvature calculation unit 160 may increase the attitude angle curvature adjustment gain K3 above its reference value and decrease the position curvature adjustment gain K2 below its reference value, where the reference value is the value of the control gain before being increased or decreased.

[0066] According to this configuration, the absolute value of the large attitude angle deviation e2 can be reduced with priority over the absolute value of the small position deviation e1, thereby improving the convergence to the target travel route.

[0067] For example, the adjustment gain may be increased or decreased when the current route section is one or more specific route sections that are set to include a turning point (for example, one or more specific route sections after the turning point). * When the angle of the steering wheel changes, the attitude angle deviation e2 increases, but the position deviation e1 does not change much. Therefore, the absolute value of the attitude angle deviation e2, which has increased before and after the turning point, can be reduced with priority over the absolute value of the position deviation e1, which does not change much before and after the turning point.

[0068] On the other hand, when the absolute value of the attitude angle deviation e2 is less than the attitude angle judgment value and the absolute value of the position deviation e1 is equal to or greater than the position deviation judgment value, the target curvature calculation unit 160 decreases the attitude angle curvature adjustment gain K3 below the reference value and increases the position curvature adjustment gain K2 above the reference value.

[0069] According to this configuration, the absolute value of the large positional deviation e1 can be reduced with priority over the absolute value of the small attitude angle deviation e2, thereby improving the convergence to the target travel path.

[0070] <Changing adjustment gains according to curvature and inside or outside of protruding direction> As shown in FIG. 18 , when the current section planned route is a curve, the target curvature calculation unit 160 may change one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 depending on whether the current vehicle position is located inside or outside of the protruding direction of the target driving route.

[0071] When the current vehicle position is located inside the target driving route in the direction of projection, the target driving route geometrically approaches the vehicle as the vehicle moves in the traveling direction. On the other hand, when the current vehicle position is located outside the target driving route in the direction of projection, the target driving route geometrically moves away from the vehicle as the vehicle moves in the traveling direction. Therefore, even if the attitude angle deviation e2 and position deviation e1 are the same and the adjustment gains K1, K2, and K3 are the same, the convergence to the target driving route geometrically changes depending on whether the vehicle position is located outside or inside the target driving route. By changing the adjustment gains depending on whether the vehicle position is located outside or inside the target driving route, the convergence to the target driving route can be improved.

[0072] For example, when the current vehicle position is located inside the target driving path in the protruding direction, the target curvature calculation unit 160 decreases one or more of the position angle adjustment gain K1, position curvature adjustment gain K2, and attitude angle curvature adjustment gain K3 (e.g., position angle adjustment gain K1) from a reference value, and when the current vehicle position is located outside the target driving path in the protruding direction, the target curvature calculation unit 160 increases one or more of the position angle adjustment gain K1, position curvature adjustment gain K2, and attitude angle curvature adjustment gain K3 (e.g., position angle adjustment gain K1) from a reference value. Here, the reference value is the value of the control gain before being increased or decreased.

[0073] According to this configuration, when the vehicle position is located inside the target driving route, convergence to the target driving route is geometrically improved, so by decreasing the adjustment gain, convergence is deteriorated in terms of control, and the geometric improvement in convergence and the control-related deterioration in convergence are balanced, thereby optimizing the convergence.When the vehicle position is located outside the target driving route, convergence to the target driving route is geometrically deteriorated, so by increasing the adjustment gain, convergence is improved in terms of control, and the geometric deterioration in convergence and the control-related improvement in convergence are balanced, thereby optimizing the convergence.

[0074] The target curvature calculation unit 160 determines whether the target driving route curves to the left or right of the traveling direction based on the target driving route (for example, the positive or negative value of the second-order differential coefficient of the target driving route in equations (12), (15), and (17)), and determines whether the host vehicle is located to the left or right of the traveling direction with respect to the target driving route based on the relative position between the target driving route and the current host vehicle position (the positive or negative value of the position deviation e1 calculated in equation (20)). For example, as shown in FIG. 18 , if the target driving route curves to the left of the traveling direction, the outside of the protruding direction is the right side of the traveling direction of the target driving route, and the inside of the protruding direction is the left side of the traveling direction of the target driving route.

[0075] When the current section planned route is curved, the target curvature calculation unit 160 may change one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 based on the curvature of the target driving route.

[0076] When the curvature of the target travel route changes, the appropriate adjustment gain changes accordingly. Therefore, by changing the adjustment gain based on the curvature of the target travel route, it is possible to optimize the convergence.

[0077] For example, when the current section planned route is curved, the target curvature calculation unit 160 may increase one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 (e.g., the position angle adjustment gain K1) from a reference value as the absolute value of the curvature of the target driving route increases. Here, the reference value is the value of the control gain before being increased or decreased (e.g., the value of the control gain when the current section planned route is straight).

[0078] As the absolute value of the curvature of the target driving route increases, the steering amount required to make the vehicle follow the target driving route increases. Therefore, by increasing the adjustment gain as the absolute value of the curvature of the target driving route increases, convergence can be improved.

[0079] For example, the curvature of the target driving path is calculated by using the second-order derivative of the target driving path in Equation (12), Equation (15), or Equation (17). Note that the third-order derivative corresponding to the curvature change rate may also be considered.

[0080] Furthermore, when the current section planned route is curved and the current vehicle position is on the outside of the projecting direction of the target traveling route, the target curvature calculation unit 160 may gradually increase one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 (for example, the position angle adjustment gain K1) from a reference value as the absolute value of the curvature of the target traveling route increases. Furthermore, when the current vehicle position is on the inside of the projecting direction of the target traveling route, the target curvature calculation unit 160 may gradually decrease one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3 (for example, the position angle adjustment gain K1) from a reference value as the absolute value of the curvature of the target traveling route increases.

[0081] When the vehicle position is outside the protruding direction of the target driving route, the convergence gradually deteriorates geometrically as the absolute value of the curvature of the target driving route increases. Therefore, by gradually increasing the adjustment gain as the absolute value of the curvature of the target driving route increases and gradually improving the convergence in terms of control, it is possible to balance the deterioration of the geometric convergence and the improvement of the convergence in terms of control, and to optimize the convergence. On the other hand, when the vehicle position is inside the protruding direction of the target driving route, the convergence gradually improves geometrically as the absolute value of the curvature of the target driving route increases. Therefore, by gradually decreasing the adjustment gain as the absolute value of the curvature of the target driving route increases and gradually improving the convergence in terms of control, it is possible to balance the deterioration of the geometric convergence and the improvement of the convergence in terms of control, and to optimize the convergence.

[0082] <Flowchart of Parking Control Device 300> Next, a schematic processing procedure (parking control method) of the parking control device 300 according to this embodiment will be described with reference to the flowchart shown in FIG.

[0083] In step S100, as described above, the host vehicle information acquisition unit 120 acquires the current host vehicle position and the current host vehicle attitude angle. In step S101, as described above, the surrounding environment acquisition unit 100 acquires the surrounding environment such as the corner position of the parking space and the aisle boundary. In step S102, as described above, the target parking position information setting unit 110 sets the target parking position and the target parking attitude angle for parking the host vehicle based on the surrounding environment such as the corner position of the parking space and the aisle boundary.

[0084] In step S103, as described above, the no-travel area generating unit 130 sets the no-travel area based on the surrounding environment such as the corner position of the parking space and the passage boundary, etc. In step S104, the parking path planning unit 140 generates a planned path having multiple route sections from the control start position to the target parking position.

[0085] In step S105, as described above, the target route generation unit 150 determines the current route section, which is the route section corresponding to the current vehicle position, and generates a target driving route for the current route section based on the current section planned route, which is the planned route for the current route section.

[0086] In step S106, as described above, the target curvature calculation unit 160 calculates the position deviation of the current host vehicle position with respect to the target driving route and the tangential direction of the target driving route, calculates a target attitude angle of the host vehicle at the current host vehicle position based on the position deviation and the tangential direction, and calculates a target driving curvature ρ of the host vehicle that reduces the attitude angle deviation of the current host vehicle attitude angle with respect to the target attitude angle and the position deviation. * Calculate the following.

[0087] In step S107, as described above, the steering control unit 170 calculates the target traveling curvature ρ calculated in step S201. * Based on this, the target steering angle δ * and calculate the target steering angle δ *The steering angle of the vehicle is controlled based on the above.

[0088] In step S108, it is determined whether the vehicle has reached the target parking position and the target parking attitude angle. If it has, the process ends, and if it has not, the process returns to step S100.

[0089] <Flowchart of target path generation unit 150 and target curvature calculation unit 160> Next, using the flowchart shown in Figure 20, we will explain the general processing procedure (parking control method) of the target path generation unit 150 and the target curvature calculation unit 160 according to this embodiment.

[0090] In step S200, as described above, the target route generation unit 150 determines the current route section, which is the route section corresponding to the current vehicle position. In step S201, the target route generation unit 150 determines whether the current section planned route is curved or straight. If it is curved, the process proceeds to step S202, and if it is straight, the process proceeds to step S203.

[0091] In step S202, as described above, the target route generation unit 150 generates a target driving route by approximating the current section planned route to a polynomial curve. In step S203, as described above, the target route generation unit 150 generates a straight-line target driving route based on the current section planned route.

[0092] In step S204, as described above, the target curvature calculation unit 160 calculates the position deviation e1 of the current vehicle position with respect to the target driving route and the tangent direction γ of the target driving route using the target driving route. † Calculate the following.

[0093] In step S205, as described above, the target curvature calculation unit 160 sets the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3. In this embodiment, the target curvature calculation unit 160 changes one or more of the position angle adjustment gain K1, the position curvature adjustment gain K2, and the attitude angle curvature adjustment gain K3. One or more of the above-described methods for changing the adjustment gains are used to change each adjustment gain.

[0094] In step S206, as described above, the target curvature calculation unit 160 calculates the position deviation e1 and the tangent direction γ of the target travel path. † Based on this, the target attitude angle γ of the host vehicle at the current host vehicle position is calculated. * At this time, the position angle adjustment gain K1 is used.

[0095] In step S207, as described above, the target curvature calculation unit 160 calculates the target attitude angle γ of the host vehicle. * The current vehicle attitude angle γ ego The target driving curvature ρ of the vehicle is set so that the attitude angle deviation e2 and the position deviation e1 of the vehicle are reduced. * At this time, the position curvature adjustment gain K2 and the attitude angle curvature adjustment gain K3 are used.

[0096] 2. Second Embodiment Next, a parking control device 300 according to a second embodiment will be described. Description of the same components as those in the first embodiment will be omitted. The basic configuration of the parking control device 300 according to this embodiment is the same as that of the first embodiment, but processing by a target curvature calculation unit 160 is added to the first embodiment.

[0097] In this embodiment, the target curvature calculation unit 160 calculates the target traveling curvature ρ * When the vehicle is driven based on the target curvature ρ, it is determined whether the vehicle will enter the no-entry area, and if it is determined that the vehicle will enter the no-entry area, the target curvature ρ * Change the

[0098] According to this configuration, the target driving curvature ρ * Since the vehicle is prevented from entering a no-entry area, the vehicle can be made to converge on the target driving route.

[0099] As shown on the left side of FIG. 21, the target curvature calculation unit 160 calculates a target traveling curvature ρ *The travel path of the host vehicle and the range of movement of the host vehicle's contour are predicted by the above formula. For example, the case where the host vehicle is moved by a determined distance is predicted. If the range of movement of the host vehicle's contour enters a no-entry area, the target curvature calculation unit 160 repeatedly calculates the target travel curvature ρ until the range of movement of the host vehicle's contour does not enter the no-entry area. * is changed in an increasing or decreasing direction so as to reduce the risk of intrusion into the no-entry area. As shown on the right side of Figure 21, although the convergence to the target driving route deteriorates, it is possible to make the host vehicle travel along the target driving route while preventing intrusion into the no-entry area.

[0100] 22 shows a flowchart of the target route generation unit 150 and the target curvature calculation unit 160 according to this embodiment. Steps S200 to S207 in FIG. 22 are the same as steps S200 to S207 in FIG. 20 according to the first embodiment, and therefore a description thereof will be omitted. In this embodiment, in step S208, as described above, the target curvature calculation unit 160 calculates the target traveling curvature ρ * When the vehicle is driven based on the target curvature ρ, it is determined whether the vehicle will enter the no-entry area, and if it is determined that the vehicle will enter the no-entry area, the target curvature ρ * Change the

[0101] <Hardware Configuration of Parking Control Device 300> Fig. 23 is a hardware configuration diagram including the parking control device 300 according to the first and second embodiments. For example, as shown in Fig. 23, the processor H101 reads and executes a program stored in the memory H102, thereby realizing each function of the parking control device 300. Furthermore, the functions of the parking control device 300 according to the first and second embodiments may be installed into the memory H102 from the storage medium H103 in which the program H104 is stored. As described above, the functions of the parking control device 300 according to the first and second embodiments can be realized by software, hardware, etc., or a combination thereof.

[0102] Although various exemplary embodiments and examples are described in this disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this disclosure specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0103] 140: Parking path planning unit, 150: Target path generation unit, 160: Target curvature calculation unit, 170: Steering control unit, 300: Parking control device, K1: Position angle adjustment gain, K2: Position curvature adjustment gain, K3: Attitude angle curvature adjustment gain, e1: Position deviation, e2: Attitude angle deviation, f(x, y): Target driving path, γ * :Target attitude angle, γ † :Tangential direction, γ ego : Vehicle attitude angle, ρ * : Target curvature

Claims

1. A parking control device comprising: a parking route planning unit that generates a planned route having a plurality of route sections from a control start position to a target parking position; a target route generation unit that determines a current route section that corresponds to a current vehicle position and generates a target travel route for the current route section based on a current section planned route that is the planned route of the current route section; and a target curvature calculation unit that calculates a position deviation of the current vehicle position with respect to the target travel route and a tangential direction of the target travel route, calculates a target attitude angle of the vehicle at the current vehicle position based on the position deviation and the tangential direction, and calculates a target travel curvature of the vehicle such that an attitude angle deviation between the target attitude angle and the current vehicle attitude angle and the position deviation decrease.

2. The parking control device according to claim 1, wherein when the current section planned route is a curve, the target route generation unit approximates the current section planned route with a polynomial curve to generate the target travel route, and when the current section planned route is a curve, the target curvature calculation unit calculates the position deviation and the tangential direction using the polynomial curve.

3. The parking control device according to claim 1 or 2, wherein the target curvature calculation unit varies one or more of a position angle adjustment gain that is an adjustment gain for adjusting a change amount of an inclination angle of the target attitude angle with respect to the position deviation, a position curvature adjustment gain that is an adjustment gain for adjusting a change amount of the target travel curvature with respect to the position deviation, and an attitude angle curvature adjustment gain that is an adjustment gain for adjusting a change amount of the target travel curvature with respect to the attitude angle deviation.

4. The parking control device according to claim 3, wherein the target curvature calculation unit varies one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain according to a type of parking method.

5. The parking control device according to claim 3, wherein when the current section planned route is a curve, the target curvature calculation unit varies one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain according to whether the current vehicle position is located outside or inside a protruding direction of the target travel route.

6. The parking control device according to claim 3, wherein when the current section planned path is a curve, if the current vehicle position is located inside the protruding direction of the target travel path, the target curvature calculation unit decreases one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain from a reference value, and if the current vehicle position is located outside the protruding direction of the target travel path, the target curvature calculation unit increases one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain from the reference value.

7. The parking control device according to claim 3, wherein when the current section planned path is a curve, the target curvature calculation unit changes one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain based on the curvature of the target travel path.

8. The parking control device according to claim 3, wherein when the current section planned path is a curve, as the absolute value of the curvature of the target travel path increases, the target curvature calculation unit increases one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain from a reference value.

9. The parking control device according to claim 3, wherein when the current section planned path is a curve, if the current vehicle position is outside the protruding direction of the target travel path, as the absolute value of the curvature of the target travel path increases, the target curvature calculation unit gradually increases one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain from a reference value, and if the current vehicle position is inside the protruding direction of the target travel path, as the absolute value of the curvature of the target travel path increases, the target curvature calculation unit gradually decreases one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain from the reference value.

10. The parking control device according to claim 3, wherein when the current path section is one or more specific path sections set including a turning point, the target curvature calculation unit changes one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain.

11. The parking control device according to claim 3, wherein the target curvature calculation unit changes one or more of the position angle adjustment gain, the position curvature adjustment gain, and the attitude angle curvature adjustment gain based on the position deviation and the attitude angle deviation.

12. The parking control device according to claim 11, wherein when the absolute value of the attitude angle deviation is greater than or equal to a determination value of the attitude angle deviation and the absolute value of the position deviation is less than a determination value of the position deviation, the target curvature calculation unit increases the attitude angle curvature adjustment gain from a reference value and decreases the position curvature adjustment gain from the reference value.

13. The parking control device according to claim 11, wherein when the current path section is one or more specific path sections set including a switching point, the absolute value of the attitude angle deviation is greater than or equal to a determination value of the attitude angle deviation, and the absolute value of the position deviation is less than a determination value of the position deviation, the target curvature calculation unit increases the attitude angle curvature adjustment gain from a reference value and decreases the position curvature adjustment gain from the reference value.

14. The parking control device according to claim 11, wherein when the absolute value of the attitude angle deviation is less than a determination value of the attitude angle deviation and the absolute value of the position deviation is greater than or equal to a determination value of the position deviation, the target curvature calculation unit decreases the attitude angle curvature adjustment gain from a reference value and increases the position curvature adjustment gain from the reference value.

15. The parking path planning unit generates the current section planned path of the curve using at least a clothoid curve or an arc. When the current section planned path is a curve, the target curvature calculation unit approximates the current section planned path to a polynomial curve using polynomial fitting or Taylor expansion to generate the target travel path. The parking control device according to claim 2.

16. The parking control device according to claim 2 or 15, wherein when the current section planned path is a curve, the target curvature calculation unit decreases the degree of the polynomial curve as the length of the current section planned path becomes shorter.

17. The parking control device according to claim 1, wherein the target curvature calculation unit determines whether the host vehicle enters a prohibited entry area when the host vehicle travels based on the target travel curvature, and when it is determined that the host vehicle enters, changes the target travel curvature so as not to enter.

18. The parking control device according to claim 1, further comprising a steering control unit that calculates a target steering angle based on the target travel curvature and controls the steering angle of the host vehicle based on the target steering angle.

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