JP2008296638A - Parking support device, display device, target locus setting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parking support device, and a target locus setting method, expanding a parkable area by lessening a restriction of geometric positional condition. <P>SOLUTION: The parking support device 10 calculates a target locus S from a parking start position O to a target parking position to guide a vehicle. The parking support device 10 comprises: a determination means 23 determining whether or not the initial target locus is intersect with a line of a long axis (Z-axis) of a parking section 34, when the vehicle cannot be guided to the target parking position G by an initial target locus in which a steering angle is not changed beyond a neutral state; and a target locus setting means 24 setting the target locus S according to a determination result by the determination means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a parking assistance apparatus and a target locus setting method for calculating a target locus from a parking start position to a target parking position and guiding a vehicle.

  Calculates the target parking position where the vehicle should be parked and the target locus to the target parking position, displays the target locus together with a guide line such as a vehicle width line, or automatically steers the vehicle along the target locus. Parking assistance devices are known. Here, the target trajectory is a trajectory that does not change the steering direction beyond the neutral state during support (hereinafter referred to as a one-circle trajectory model), and a trajectory that changes the steering direction once after the neutral state during support, that is, A trajectory (hereinafter referred to as a two-circle trajectory model) that needs to change the steering direction from the state steered rightward (leftward) to the leftward (rightward) beyond the neutral state is calculated. sell.

Both the 1-circle and 2-circle models can calculate the target locus to the target parking position when the parking start position (current position) with respect to the target parking position satisfies the geometrical position condition. The geometric position condition can be relaxed by making the trajectory model available. In view of this, there has been proposed a parking assist device that calculates a target locus using a two-circle trajectory model when the target locus cannot be calculated using a one-circle trajectory model (see, for example, Patent Document 1).
JP 2003-31413 A

  However, there is a problem that there is a restriction in the geometric position condition in which the locus calculation is possible even in the conventional two-circle orbit model. FIG. 13 shows an example of the target locus of the two-circle trajectory model at the time of parking in the garage. The vehicle is in the Ko position at the parking start position. When the target locus is represented by a locus through which the axle center of the rear wheel passes, the target locus S is a locus for guiding from the parking start position O to the target parking position G. The sections OA and CG are linear trajectories, the section AB is an arc centered at the point P1, and the section BC is an arc centered at the point P2 (may include a clothoid part). Therefore, the steering direction is switched beyond the neutral state at point B.

  In the conventional two-circle trajectory model, the path length from the parking start position O to the target parking position G is calculated to be as short as possible, so that the target path S does not exceed the Z axis (vehicle length direction) of the target parking frame. Has been calculated. For this reason, there is a restriction on the geometric position condition where the target locus can be calculated. In the figure, if the predetermined area N and the predetermined area F determined by the distance and direction of the position Ko of the vehicle with respect to the Z axis become the parking start position O, there is a possibility that the target locus S that leads to the target parking position G can be set in the case of the two-circle trajectory model Even if there is, it has been determined that the calculation of the target locus S is difficult.

  An object of this invention is to provide the parking assistance apparatus and the target locus | trajectory setting method which can ease the restrictions of geometric position conditions and can expand a parking possible area | region in view of the said subject.

  In view of the above problems, the present invention provides a parking assist device that calculates a target locus from a parking start position to a target parking position and guides the vehicle, and the target parking position is determined by an initial target locus in which the steering angle does not change beyond the neutral state. A determination unit that determines whether or not the initial target locus intersects the long axis of the parking area, and a target locus setting unit that sets the target locus according to the determination result by the determination unit. It is characterized by.

  According to the present invention, the target trajectory is set depending on whether or not the one-circle trajectory model intersects with the long axis of the parking section, so that the restriction of the geometric position condition is eased and the parking area is expanded. can do.

  In one embodiment of the present invention, when the determination unit determines that the initial target trajectory intersects the long axis, the target trajectory setting unit is a target trajectory in which the steering angle changes beyond the neutral state, If the direction of the steering angle before changing beyond the state sets the same target locus as the initial target locus, and it is determined that the initial target locus does not intersect the long axis, the target locus setting means The target trajectory changes beyond the neutral state, and the direction of the steering angle before changing beyond the neutral state is set to a target trajectory opposite to the initial target trajectory.

  According to the present invention, when the one-circle trajectory model intersects with the long axis of the parking section, a target trajectory is set by the same two-circle trajectory model as the one-circle trajectory model after the start of parking, When the model does not intersect the long axis of the parking section, the parking area can be expanded by setting a target trajectory based on a two-circle trajectory model that is the reverse of the one-circle trajectory model after the start of parking. .

  It is possible to provide a parking assist device and a target trajectory setting method that can relax the restriction of the geometric position condition and expand the parking area.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating an example of a geometric position condition in which a trajectory can be calculated using a two-circle trajectory model. The parkable area in FIG. 1 is an area in which a target locus up to the target parking position G can be calculated using a one-circle orbit model and a conventional two-circle orbit model. The parking assist device 10 according to the present embodiment allows the region N to be a parkable region by allowing a target locus that exceeds the Z-axis (vehicle length direction) of the parking section 34. If the Z axis (vehicle length direction) of the parking section 34 is not exceeded, the target trajectory is calculated by the two-circle trajectory model that steers beyond the neutral state after steering in the opposite direction to the one-circle trajectory model. Thus, this parking area can be expanded to the area F.

  FIG. 2 shows an example of a schematic configuration diagram of the parking assistance device 10. The parking assistance device 10 is controlled by the parking assistance ECU 20. The parking assist ECU 20 is configured as a microcomputer including a CPU, a ROM, a RAM, an input / output interface serving as a data interface, a communication controller communicating with another computer, and the like connected to each other via a bus. When the CPU executes the program, the determination unit 23, the target locus setting unit 24, and the maximum point steering angle calculation unit 25 are realized. The determination means 23 determines whether or not the 1-circle trajectory model intersects with the Z line of the parking section 34, and the target trajectory setting means 24 sets the target trajectory S based on the 1-circle trajectory model and the 2-circle trajectory model. The maximum point rudder angle calculating means 25 calculates the maximum value of the traveling direction of the vehicle that can be changed by turning the first circle in the direction of the vehicle.

  The parking assistance ECU 20 is provided in the vehicle interior with an operation input means 11 for inputting a driver's operation such as a touch panel and a voice input device via a vehicle LAN such as a CAN (Controller Area Network) and a LIN (Local Interconnect Network). Touch panel display 12, rear camera 13 disposed in the center of the bumper at the rear of the vehicle, reverse shift switch 14 that outputs an ON signal when the shift position is in the reverse position, and a parking switch that activates the parking assist device 10 15 is connected.

  The rear camera 13 is a CCD camera that captures a landscape in a predetermined angle area behind the vehicle, and supplies the captured image signal to the parking assist ECU 20. The parking assistance ECU 20 determines that the driver needs parking assistance when the parking switch 15 is in the on state. If the reverse shift switch 14 outputs an on signal, the parking assistance ECU 20 indicates that the vehicle is moving backward. To detect.

  By such an operation, the parking assistance ECU 20 displays the captured image captured by the rear camera 13 shown in FIG. The parking assist ECU 20 superimposes and displays the target parking frame 31 on the captured image and superimposes and displays a touch-type touch switch 32 for setting the parking target position. The driver uses the touch switch 32 to move the target parking frame 31 on the display 12 to adapt the target parking frame 31 to the actual parking section 34. At this time, if the pole 33 indicating the innermost position of the obstacle is displayed, it is possible to easily calculate a target locus avoiding the obstacle.

  Here, since the position and the optical axis of the rear camera 13 are fixed, each pixel of the target parking frame 31 and the actual position of the parking section 34 are based on the difference in the number of pixels of the rear camera 13 and the display 12. Therefore, the parking support ECU 20 detects the distance to the target parking frame 31 and the direction of the vehicle from this correspondence. Further, since the space required for the target parking frame 31 is the size of the host vehicle, the target parking frame 31 automatically becomes a figure imitating the outer shape of the host vehicle.

The coordinate value of the target parking frame 31 on the display 12 is managed in a coordinate system that represents the position and orientation of the target parking frame 31. Specifically, the position of the target parking frame 31 on the display 12 is expressed in a two-dimensional coordinate system in which the axis corresponding to the axle is the Z axis and the axis orthogonal to the Z axis is the X axis. It is expressed as coordinates (X, Z) of the position of the reference point H on the parking frame 31. Further, the direction of the target parking frame 31 on the display 12 is the inclination δ of the reference line J of the target parking frame 31 with respect to the Z axis. It is managed by. 3 is different from the Z axis of the parking section 34 in FIG. 1 (the coordinate system of the target parking frame 31 displayed on the display 12 and the coordinate system for calculating the target locus S are different).

  When the position and direction of the target parking frame 31 are determined on the display 12, the target locus setting unit 24 determines the position of the parking section 34 from the current vehicle position (parking start position O) based on the coordinate value of the target parking frame 31 ( A target locus for guiding the vehicle while avoiding an obstacle to the target parking position G) is calculated, and a target turning angle of a wheel to be steered at each position on the target locus is calculated.

  FIG. 4 is a diagram showing the target trajectory S and the relationship between the travel distance and the turning curvature. This target trajectory S is a one-circle trajectory model, and the process of retreating with the rudder angle neutral (section OA), the process of increasing the rudder angle at a constant speed (section AB), and the process of maintaining the increased rudder angle (Section BC), a process of returning the steering angle to neutral at a constant speed (section CD), and a process of retreating with the steering angle neutral (section DG).

  In such a target trajectory S, the turning curvature of the target trajectory S remains zero from point O to point A, and the turning curvature increases at a constant speed from point A to point B. It matches the turning curvature. That is, the turning radius is the minimum turning radius of the vehicle. From point B to point C, the maximum turning curvature is maintained. From point C, the turning curvature decreases at a constant speed, returns to the rudder angle neutral at point D, and reverses in a neutral state from point D to point G. . As a result, in the target locus S, the section OA and the section DG are straight lines, the section BC is a circular arc with the minimum turning radius, and the sections AB and the section CD are respectively a curved curvature curve with one end having the maximum turning curvature and the other end having a zero curvature. . Depending on the target trajectory S, not all of these processes may be performed.

  The parking assist ECU 20 is connected to a steering angle sensor 18 that detects the steering angle Ha of the steering wheel and a wheel speed sensor 16 that detects the speed V of the vehicle. The wheel speed sensor 16 is a sensor that is disposed in each wheel, for example, and generates a pulse signal at a cycle corresponding to the wheel speed. By monitoring the steering angle Ha on the basis of the direction of the vehicle at the parking start position O in the neutral steering state, the direction of the vehicle is detected at each position on the target locus S, and the pulse signal of the wheel speed sensor 16 is integrated. By doing so, the travel distance is detected. Therefore, the parking assist ECU 20 can guide the vehicle to the target parking position G according to the relationship between the travel distance and the turning curvature in FIG.

  An electric power steering ECU 17 and an electric power steering ACT 19 are connected to the parking assist ECU 20. The electric power steering ACT 19 is an actuator that rotationally drives the steering shaft via a reduction gear. The parking assist ECU 20 outputs a steering request to the electric power steering ECU 17 so that the vehicle is guided to the parking target position along the target locus. When the driver weakens the depression force of the brake pedal and the vehicle starts to move backward due to the creep force, the parking assist ECU 20 measures the vehicle position and direction with the wheel speed sensor 16 and the steering angle sensor 18 and reaches the parking target position G. The electric power steering ECU 17 is automatically turned by the target turning angle at each vehicle position. When the vehicle finally reaches the target parking position G, the driver is requested to stop the vehicle, or braking is automatically applied to stop the vehicle, and the parking support control is completed.

  In addition, clearance sonar R21 clearance sonar L22 is arrange | positioned at the right and left of the side surface of a front bumper, and when an obstacle approaches while driving | running | working a target locus | trajectory, it alert | reports to a driver | operator by sounding an automatic stop or an alarm. In addition, the vehicle travels along the reference line J before calculating the target trajectory, and the other vehicle adjacent to the parking section 34 is detected by the clearance sonar R21 and the clearance sonar L22, so that the parking section 34 is accurately recognized. can do.

  Next, a method for setting the target locus S for extending the parking area to the area F and the area N in FIG. 1 will be described based on the flowchart in FIG.

(S10)
First, the target parking frame 31 is determined by the driver. The target locus setting means 24 determines that the driver needs parking assistance by the reverse shift switch 14 and the parking switch 15 and calculates the target locus S. At this time, as shown in FIG. 6, it is assumed that the vehicle is present at any of positions Pok, PN, and PF with respect to the parking section 34. The position Pok is a position where the target trajectory S that is guided to the target parking position G by the one-circle trajectory model can be calculated. The position PN is a position where the target trajectory S is difficult to calculate by the one-circle trajectory model, and the target trajectory S is the Z axis. The position PF indicates a position where the target trajectory S is difficult to calculate in the one-circle trajectory model and the target trajectory S does not intersect the Z axis.

(S20)
Next, the target trajectory setting means 24 determines whether or not the target trajectory S based on the one-circle trajectory model can be calculated based on the position and direction of the vehicle at the parking start position O with respect to the target parking position G. Whether or not parking is possible in the parking section 34 by the one-circle trajectory model is performed by, for example, setting the coordinates of the parking start value O (X0, Z0), the minimum turning radius R, θ on the axle of the vehicle at the parking start position O. If the angle formed by the Z axis of 34 is Z0 ≧ Rsinθ and X0 ≧ R (1-cosθ), it is determined that parking is possible by the one-circle trajectory model. The determination may be made using a predetermined map.

(S30)
When the target trajectory S can be calculated from the one-circle trajectory model (Yes in S20), the parking assist ECU 20 displays a parking available display on the display 12. Further, the target trajectory S based on the one-circle trajectory model is superimposed and displayed on the captured image captured by the rear camera 13. When the driver inputs an operation to start parking, the electric power steering ECU 17 automatically turns the target steering angle at each vehicle position up to the parking target position G while measuring the vehicle position by the wheel speed sensor 16. Since the target trajectory S at this time is calculated by applying a one-circle trajectory model, the calculation load is low and processing can be performed quickly.

(S40)
When the target trajectory S cannot be calculated from the one-circle trajectory model (No in S20), the determination unit 23 determines whether or not the target trajectory S based on the one-circle trajectory model intersects the Z axis. If the position Z0 in the Z direction is, for example, Z0 <Rsinθ, it is determined that the target locus S does not intersect with the Z axis. If the position X0 in the X direction is, for example, X0 <R (1-cosθ), it intersects with the Z axis. Judge that. According to FIG. 6, the target trajectory S calculated at the position PN intersects with the Z axis and is determined as Yes, and the target trajectory S calculated at the position PF does not intersect with the Z axis and is determined as No.

(S50)
When the target trajectory S based on the one-circle trajectory model intersects the Z axis, the target trajectory setting means 24 calculates the maximum turning angle θ _MAX in the target trajectory S from the parking start position O to the target parking position G at the position PN. . Since the target trajectory S cannot be calculated with the one-circle trajectory model, the target trajectory S here is a two-circle trajectory model.

FIG. 7 is a diagram illustrating the relationship between the maximum turning angle θ _MAX of the target locus S at the position PN, the travel distance, and the turning curvature.
Section OA: Process of retreating with neutral rudder angle (turning curvature zero)
Section AB: Process of decreasing the rudder angle at a constant speed (clothoid curve)
Section BC: Process of maintaining the reduced rudder angle (maximum turning curvature (-) around point P1)
Position C: Section in which the rudder angle is increased at a constant speed CD: Process of maintaining the increased rudder angle (maximum turning curvature (+) around the point P2)
Section DE: The process of decreasing the rudder angle at a constant speed (clothoid curve)
Section EG: The process of retreating with the rudder angle neutral (turning curvature zero)
In addition, the case of steering to the right from the neutral state is positive, and the case of steering to the left is negative. Further, for the sake of explanation, the steering angle changes from the minimum steering angle (maximum on the left) to the maximum steering angle (maximum on the right) in the stopped state at the position C, but a clothoid curve may be drawn while moving.

The maximum turning angle θ _{MAX in} FIG. 7 is an angle formed by the tangent L2 between the point C in the arc CD and the point C in the arc BC and the initial direction line L1 orthogonal to the axle at the parking start position O. That is, the maximum turning angle θ _MAX is a turning angle by the section OC.

Normally, when calculating the target trajectory S using a two-circle trajectory model, it is not clear how much the vehicle should be tilted at the position C, but the loop calculation is performed, but the calculation may take time. In the present embodiment, the calculation load is reduced by calculating the maximum turning angle θ _MAX and calculating the target trajectory S in a range where the turning angle is equal to or less than θ _MAX .

FIG. 8 is an explanatory diagram for explaining the calculation of θ _{MAX at} the position PN. The angle θ formed by the initial direction line L1 and the Z axis is known, and θ _MAX = θ + α when the turning angle of the section CD is α. Therefore, if α is known, θ _Max is also known.

Since the maximum turning curvature of the sections BC and CD is known, the target trajectory setting means 24 can obtain the tangent L2 that can be taken before calculating the target trajectory S, and the initial direction line within the range of the possible tangent L2 A maximum turning angle θ _MAX at which the angle formed by L1 is maximum is calculated.

If the coordinates of the parking start value O are (X0, Z0), X0 and Z0 can be expressed as follows, where R is the minimum turning radius.
X0 = R (2cos α-1) −R cos θ (i)
Z0 = 2Rsinα + Rsinθ (ii)
Therefore, α can be expressed by the following equation.
α = arccos {(X0 + Rcos θ + R) / 2R} (iii)
The target trajectory S can be parked at the target parking position G when the turning angle from the parking start position O to the position C is smaller than θ _MAX . In other words, the target trajectory is within the range of the maximum turning angle θ _MAX or less. It is sufficient to calculate S.

(S60)
When the target trajectory S in the one-circle trajectory model does not intersect the Z axis, the target trajectory setting means 24 calculates the maximum turning angle θ _MAX in the target trajectory S from the parking start position O to the target parking position G at the position PF. . Since the target trajectory S cannot be calculated with the one-circle trajectory model, the target trajectory S here is a two-circle trajectory model.

FIG. 9 is a diagram showing the relationship between the maximum turning angle θ _MAX of the target locus S at the position PF, the travel distance, and the turning curvature.
Section OA: Process of retreating with neutral rudder angle (turning curvature zero)
Section AB: Process of increasing the rudder angle at a constant speed (clothoid curve)
Section BC: Process of maintaining an increased rudder angle (maximum turning curvature around point P1 (+))
Position C: Section in which the steering angle is decreased at a constant speed CD: Process of maintaining the decreased steering angle (maximum turning curvature (-) around the point P2)
Section DE: Process of increasing the rudder angle at a constant speed (clothoid curve)
Section EG: The process of retreating with the rudder angle neutral (turning curvature zero)
In addition, the case of steering to the right from the neutral state is positive, and the case of steering to the left is negative. For the sake of explanation, the steering angle changes from the minimum steering angle (maximum on the right) to the maximum steering angle (maximum on the left) in the stopped state at the position C. However, a clothoid curve may be drawn while moving.

The maximum turning angle θ _{MAX in} FIG. 9 is an angle formed by the tangent L2 between the point C in the arc CD and the point C in the arc BC and the initial direction line L1 orthogonal to the axle at the parking start position O. That is, the maximum turning angle θ _MAX is a turning angle by the section OC.

Normally, when calculating the target trajectory S using a two-circle trajectory model, it is not clear how much the vehicle should be tilted at the position C, but the loop calculation is performed, but the calculation may take time. In the present embodiment, the calculation load is reduced by calculating the maximum turning angle θ _MAX and calculating the target trajectory S in a range where the turning angle is equal to or less than θ _MAX .

FIG. 10 is an explanatory diagram for explaining the calculation of θ _{MAX at} the position PF. The angle θ formed between the initial direction line L1 and the Z axis is known, and θ _MAX = α−θ when the turning angle of the section CD is α. Therefore, if α is known, θ _Max is also known. In addition, in FIG. 10, the target locus | trajectory S when not including the case where straight section OA (travel distance L) is included is shown.

Since the maximum turning curvature of the sections BC and CD is known, the target trajectory setting means 24 can obtain the tangent L2 that can be taken before calculating the target trajectory S, and the initial direction line within the range of the possible tangent L2 A maximum turning angle θ _MAX at which the angle formed by L1 is maximum is calculated.

If the coordinates of the parking start value O are (X0, Z0), X0 and Z0 can be expressed as follows, where R is the minimum turning radius.
X0 = R (1-2 cos α + cos θ) (iv)
Z0 = R (2 sin α−sin θ) (v)
If the straight travel distance from the parking start position O is M, the following relationship is obtained.

X0−Lsin θ = R (1-2 cos α + cos θ) (vi)
Z0−L cos θ = R (2 sin α−sin θ) (vii)
From (vi) and (vii), α can be expressed by the following equation.
α = arcsin {(Z0−Lcos θ + Rsin θ) / 2R} (viii)
The target trajectory S can be parked at the target parking position G when the turning angle from the parking start position O to the position C is smaller than θ _MAX . In other words, the target trajectory is within the range of the maximum turning angle θ _MAX or less. It is sufficient to calculate S.

(S70)
Next, the target trajectory setting means 24 determines whether or not the target trajectory S of the two-circle trajectory model in which the turning angle is equal to or less than the maximum turning angle θ _MAX calculated in step S50 or S60 can be calculated. Α is calculated from an angle θ formed by the known parking start position X0, the initial direction line L1, and the Z axis of the parking section 34. Therefore, it can be determined whether or not the target locus S can be calculated only from the position Z0 in the Z-axis direction of the parking start position O.

When the target trajectory S intersects the Z axis (S50), from equation (ii), Z0 ≧ R (2sin α + sin θ) (ix)
When satisfying the above condition, it is determined that the target locus S of the two-circle orbit model has been calculated. Further, the linear movement distance L at this time is L = Z0− (R (2 sin α + sin θ)).

When the target locus S does not intersect the Z axis (S60), from the equation (v), Z0 ≧ R (2sin α−sin θ) (x)
When satisfying the above condition, it is determined that the target locus S of the two-circle orbit model has been calculated.

Since it is clear how much the vehicle should be tilted at the position C since θ _MAX is calculated, the target locus setting means 24 calculates the target locus S in a range where the turning angle is equal to or less than θ _MAX . Therefore, it is possible to minimize the loop calculation and reduce the calculation load.

In addition, since the maximum turning angle θ _MAX is determined based on the maximum turning curvature including the clothoid curve, it is possible to calculate the target locus S that is easy to generate a locus while preventing overturning.

(S80)
When the target trajectory S can be calculated by the two-circle trajectory model (Yes in S70), the parking assist ECU 20 displays a parking available display on the display 12. Further, the target trajectory S based on the two-circle trajectory model is superimposed on the photographed image photographed by the rear camera 13. When the driver inputs a parking start operation, the electric power steering ECU 17 automatically sets only the target turning angle at each vehicle position up to the parking target position G while measuring the vehicle position by the wheel speed sensor 16 and the steering angle sensor 18. Steer.

  When the target trajectory S cannot be calculated from the two-circle trajectory model (No in S70), the parking assist ECU 20 displays on the display 12 that parking is impossible and ends the process.

  FIG. 11 shows an example of the parking possible area by the target locus S crossing the Z axis. FIG. 11A shows a case where the vehicle deflection angle at the parking start position O is shallow with respect to the X axis, and FIG. 11B shows a case where the vehicle deflection angle is deep. For comparison, FIGS. 11A and 11B show a parking area by a one-circle trajectory model, but the parking area is expanded by allowing a two-circle trajectory model that intersects the Z axis.

  FIG. 12 shows an example of the parking possible area by the target locus S that does not intersect the Z axis. FIG. 12A shows a case where the vehicle deflection angle at the parking start position O is shallow with respect to the X axis, and FIG. 12B shows a case where the vehicle deflection angle is deep. For comparison, FIGS. 12A and 12B show a parking area by a one-circle trajectory model, but the parking area is expanded by allowing a two-circle trajectory model that intersects the Z axis.

As described above, the parking assist device 10 according to the present embodiment allows a trajectory having a long path length, such as a trajectory exceeding the Z-axis (vehicle length direction) of the parking section 34 or a trajectory moving away from the parking section 34. The parking area can be expanded. In addition, since the maximum point steering angle θ _MAX is calculated in advance, the impossibility of calculation can be reduced.

It is a figure which shows an example of the geometrical position conditions in which a locus | trajectory calculation is possible by a 2 circle locus model. It is an example of the schematic block diagram of a parking assistance apparatus. It is a figure which shows an example of the picked-up image displayed on a display. It is a figure which shows the relationship between the target locus | trajectory S and a travel distance, and a turning curvature. It is a flowchart figure which shows the procedure of the setting method of the target locus | trajectory S which expands a parking possible area | region. It is a figure which shows an example of the relationship between a parking area and the position of a vehicle. It is a figure which shows the relationship of the maximum turning angle (theta) _MAX of the target locus | trajectory S in the position PN, a travel distance, and a turning curvature. It is explanatory drawing explaining calculation of (theta) _MAX in position PN. It is a figure which shows the relationship of the maximum turning angle (theta) _MAX of the target locus | trajectory S in the position PF, a travel distance, and a turning curvature. It is explanatory drawing explaining calculation of (theta) _MAX in position PF. It is a figure which shows an example of the parking possible area | region by the target locus | trajectory S which cross | intersects a Z-axis. It is a figure which shows an example of the parking possible area | region by the target locus | trajectory S which does not cross | intersect a Z-axis. It is a figure which shows an example of the target locus | trajectory of the 2-circle track | orbit model at the time of garage parking (conventional figure).

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Parking assistance apparatus 11 Operation input means 12 Display 13 Rear camera 14 Reverse shift switch 15 Parking switch 16 Wheel speed sensor 17 Electric power steering ECU
18 Steering angle sensor 19 Electric power steering ACT
20 Parking assistance ECU
21 Clearance Sonar R
22 Clearance Sonar L
23 determining means 24 target trajectory setting means 25 maximum point rudder angle calculating means

Claims (7)

In the parking assistance device that guides the vehicle by calculating the target locus from the parking start position to the target parking position,
If the steering angle cannot be guided to the target parking position by the initial target trajectory that does not change beyond the neutral state,
Determining means for determining whether or not the initial target trajectory intersects the long axis of the parking section;
Target trajectory setting means for setting a target trajectory according to a determination result by the determination means;
A parking assistance device comprising: When the determining means determines that the initial target trajectory intersects the long axis, the target trajectory setting means is a target trajectory in which the steering angle changes beyond the neutral state, and changes beyond the neutral state. The direction of the steering angle before starting is set to the same target locus as the initial target locus,
When it is determined that the initial target trajectory does not intersect with the long axis, the target trajectory setting means is a target trajectory in which the steering angle changes beyond the neutral state, and the steering before changing beyond the neutral state Set a target trajectory whose corner direction is opposite to the initial target trajectory.
The parking support apparatus according to claim 1, wherein A direction perpendicular to the axle of the vehicle at a predetermined position for switching the steering angle from either the left or right maximum turning curvature to the opposite turning curvature;
A direction perpendicular to the axle of the vehicle at the parking start position and a maximum turning angle calculating means for calculating a maximum turning angle formed by the vehicle;
The target trajectory setting means sets a target trajectory in which a turning angle at the predetermined position is equal to or less than the maximum turning angle.
The parking support apparatus according to claim 2, wherein   The parking assist device according to claim 2, wherein the target locus includes an arc of a maximum turning curvature of the vehicle and a clothoid portion connected to the arc.   The parking assist device according to claim 3, further comprising a vehicle steering device that steers the vehicle along the target locus.   The display apparatus which displays the said target locus | trajectory in any one of Claim 1 thru | or 4. In the target trajectory setting method of the parking assist device that guides the vehicle by calculating the initial target trajectory from the parking start position to the target parking position,
When the steering angle cannot be guided to the target parking position by the initial target trajectory that does not change beyond the neutral state,
A step of determining whether the initial target trajectory intersects the long axis of the parking section;
A target trajectory setting means for setting a target trajectory according to a determination result by the determination means;
A target trajectory setting method for a parking assistance device, comprising:

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