JP7159787B2 - Travel control device and method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cruise control device and a cruise control method for controlling travel of a vehicle so as to follow a preceding vehicle that precedes the vehicle.

BACKGROUND ART Conventionally, there has been known a travel control device that controls travel of a vehicle so as to follow the preceding vehicle while maintaining an appropriate predetermined distance between the vehicle and the preceding vehicle. It is disclosed in Document 1.

The vehicle cruise control device disclosed in Patent Document 1 is a vehicle cruise control device that recognizes the driving lane of the own vehicle and a preceding vehicle in front of the own vehicle and generates a target route on which the own vehicle follows and travels. a lane route generation unit that generates the target route as a route based on the driving lane; a preceding vehicle route generation unit that generates the target route as a route based on the travel locus of the preceding vehicle; When the condition that the driving lane cannot be stably recognized is satisfied while the vehicle is being recognized, the target route is divided into a route component based on the driving lane and a route component based on the driving locus of the preceding vehicle. and a composite route generating unit that generates a composite route by mixing with a predetermined mixing ratio.

JP 2018-24344 A

By the way, in the follow-up control, in which the own vehicle follows the preceding vehicle at an appropriate inter-vehicle distance, the travel route of the own vehicle is determined repeatedly at given time intervals by a given arithmetic processing unit according to the preceding vehicle during the control. There is a need. Therefore, if the amount of calculation (amount of information processing) for calculating the travel route of the host vehicle increases, there is a possibility that the travel route cannot be obtained within the given time interval. For example, when the travel route of the own vehicle is calculated along the travel locus of the preceding vehicle as in the travel control device disclosed in Patent Document 1, the amount of calculation increases, especially when the road curves. There is a possibility that the amount of calculation will increase if the

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cruise control device and a cruise control method capable of performing follow-up cruise control with simpler calculations.

As a result of various studies, the inventors of the present invention have found that the above object can be achieved by the present invention described below. That is, the cruise control device according to one aspect of the present invention includes a measurement unit that measures the direction of the preceding vehicle that precedes the own vehicle as the preceding vehicle direction with respect to the own vehicle, and the preceding vehicle direction measured by the measurement unit. a traveling direction processing unit that finds a new traveling direction of the own vehicle between the traveling direction of the own vehicle; A follow-up control unit that controls travel of the own vehicle so as to follow. Preferably, in the travel control device described above, the measurement unit includes a radar device that detects a target object and measures the position of the detected target object, and an imaging device that captures a traveling direction of the own vehicle and generates an image. and obtaining an image area of the preceding vehicle from the image generated by the imaging apparatus, selecting an object corresponding to the obtained image area from objects detected by the radar apparatus, and performing the selection. a processing unit for determining the position of the object measured by the radar device as a second position of the preceding vehicle.

Such a running control device can set the running direction of the follow-up running control for the preceding vehicle by arithmetic processing of obtaining a new running direction of the own vehicle between the preceding vehicle direction and the running direction of the own vehicle. Follow-up travel control is possible with simple calculations.

In the above-described travel control device, the measurement unit further measures the distance between the own vehicle and the preceding vehicle to determine the second position of the preceding vehicle relative to the first position of the own vehicle. , and the traveling direction processing unit defines an XY orthogonal coordinate system having the first position of the own vehicle as the origin, the traveling direction of the own vehicle as the X axis, and the vehicle width direction of the own vehicle as the Y axis. When set, a circle having a center point on the Y-axis and passing through the first position of the own vehicle and the second position of the preceding vehicle, from the first position of the own vehicle to the own vehicle A third position is set on the arc to the second position of the preceding vehicle in the traveling direction of the vehicle, and a line segment connecting the first position of the own vehicle and the set third position is the third position of the own vehicle. The direction from the first position to the third position is set as the new running direction of the host vehicle.

It can be inferred that the arc of the circle passing through the first position of the own vehicle and the second position of the preceding vehicle has a shape reflecting the travel locus of the preceding vehicle. Therefore, the travel control device sets the direction of the line connecting the first position of the own vehicle and the third position on the arc as the new travel direction of the own vehicle. Taking into account the trajectory, the new direction of travel of the host vehicle can be determined. In particular, when the preceding vehicle travels according to the curve of the lane, the travel control device can determine the new travel direction of the own vehicle in consideration of the curve of the lane. The third position can also be set as the target position of the own vehicle, whereby the cruise control device can set the first position of the own vehicle and the third position (the target position of the own vehicle). A connecting line segment can be set as a driving route.

In another aspect, in the above-described travel control device, the travel direction processing unit adjusts the third position based on the radius of curvature of the arc and sets the third position on the arc.

Since such a travel control device adjusts the third position based on the radius of curvature of the arc, the new travel direction of the host vehicle can be determined along the curve of the lane.

In another aspect, in the above-described cruise control device, when the radius of curvature of the arc is larger than a predetermined threshold value, the traveling direction processing unit moves the third position from the center position of the arc to the position of the preceding vehicle. When the radius of curvature of the arc is equal to the threshold value, the third position is set to the center position of the arc, and when the radius of curvature of the arc is smaller than the threshold value and setting the third position on the arc by adjusting the radius of curvature of the arc so that the third position is set closer to the first position of the own vehicle than the center position of the arc.

Since such a travel control device adjusts the third position based on the radius of curvature of the arc as described above, it is possible to determine the new travel direction of the host vehicle so as to follow the curve of the lane.

In another aspect, the cruise control device described above further includes a speed measuring unit that measures the speed of the own vehicle, and the running direction processing unit measures the speed of the own vehicle based on the speed of the own vehicle measured by the speed measuring unit. The third position is adjusted to set on the arc.

Since such a travel control device adjusts the third position based on the speed of the own vehicle, when the preceding vehicle steers to change the direction of travel, the vehicle does not swell outward or move inward. can be reduced.

In another aspect, in the above-described travel control device, the travel direction processing unit changes the third position to the The third position is set to the second position side of the preceding vehicle from the center position of the arc, and the third position is set to the center of the arc when the speed of the own vehicle measured by the speed measuring unit matches the second threshold value. position, and if the speed of the own vehicle measured by the speed measuring unit is smaller than the second threshold value, the third position is set on the first position side of the own vehicle from the center position of the arc. , the third position is adjusted and set on the arc based on the speed of the own vehicle measured by the speed measuring unit.

In such a cruise control device, when the preceding vehicle is steered to change the traveling direction and the speed of the own vehicle is greater than the second threshold value, the third position is shifted from the center position of the arc to the third position of the preceding vehicle. Since it is set on the 2nd position side, it is possible to suppress outward swelling, and when the speed of the own vehicle is smaller than the second threshold value, the third position is shifted from the center position of the arc to the first position of the own vehicle. Since it is set on the side, it is possible to suppress inward movement.

A travel control method according to another aspect of the present invention includes a measuring step of measuring a direction of a preceding vehicle that precedes the own vehicle as a preceding vehicle direction with respect to the own vehicle, and the preceding vehicle direction measured in the measuring step. A traveling direction processing step of obtaining a new traveling direction of the own vehicle between the traveling direction of the own vehicle, and a traveling direction of the preceding vehicle along the new traveling direction of the own vehicle obtained in the traveling direction processing step. a follow-up control step of controlling travel of the own vehicle so as to follow, and the measuring step further includes measuring a distance between the own vehicle and the preceding vehicle to determine the distance between the own vehicle and the preceding vehicle. The second position of the preceding vehicle is measured with respect to the position, and the traveling direction processing step takes the first position of the own vehicle as an origin, the traveling direction of the own vehicle as the X axis, and the width direction of the own vehicle. is set as the Y-axis, a circle having a center point on the Y-axis and passing through each of the first position of the own vehicle and the second position of the preceding vehicle. A third position is set on an arc extending from the first position of the vehicle to the second position of the preceding vehicle in the running direction of the own vehicle, and the first position of the own vehicle and the set third position are set. The direction of the connecting line segment from the first position of the vehicle to the third position is defined as the new running direction of the vehicle .

With this type of travel control method, the travel direction of the following travel control for the preceding vehicle can be set by arithmetic processing of obtaining a new travel direction of the own vehicle between the direction of the preceding vehicle and the travel direction of the own vehicle. Follow-up travel control is possible with simple calculations.

The cruise control device and the cruise control method according to the present invention can perform follow-up cruise control with simpler calculations.

It is a figure for demonstrating the structure of the traveling control apparatus in embodiment. FIG. 4 is a diagram for explaining a circle passing through a first position of the host vehicle and a second position of the preceding vehicle, which is required for follow-up cruise control; 3 is a diagram for explaining a third position set on an arc of the circle shown in FIG. 2; FIG. FIG. 4 is a diagram for explaining a traveling direction and a traveling route based on third positions set on the arc shown in FIG. 3; 4 is a flow chart showing an operation related to follow-up running control in the running control device; It is a figure for demonstrating one effect of the said travel control apparatus.

One or more embodiments of the invention are described below with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments. It should be noted that the configurations denoted by the same reference numerals in each figure indicate the same configurations, and the description thereof will be omitted as appropriate. In the present specification, reference numerals with suffixes omitted are used when referring to generically, and reference numerals with suffixes are used when referring to individual configurations.

FIG. 1 is a diagram for explaining the configuration of a travel control device according to an embodiment. FIG. 1A is a block diagram showing the configuration of a travel control device, and FIG. 1B is a diagram for explaining the arrangement positions of a radar device and an imaging device. FIG. 2 is a diagram for explaining a circle passing through a first position of the subject vehicle and a second position of the preceding vehicle, which is required for follow-up cruise control. FIG. 2A is a diagram for explaining the XY orthogonal coordinate system and the circle, and FIG. 2B is a diagram for explaining how to find the radius of the circle. 3 is a diagram for explaining a third position set on an arc of the circle shown in FIG. 2. FIG. FIG. 4 is a diagram for explaining the travel direction and travel route based on the third position set on the arc shown in FIG.

A cruise control device in an embodiment is a device that controls the own vehicle so as to follow the preceding vehicle while maintaining an inter-vehicle distance from the preceding vehicle that precedes the own vehicle at an appropriate predetermined distance. a measuring unit for measuring the direction of the preceding vehicle preceding the own vehicle as the preceding vehicle direction, and a new running direction of the own vehicle between the preceding vehicle direction measured by the measuring unit and the running direction of the own vehicle. and a following control unit that controls the running of the own vehicle so as to follow the preceding vehicle while following the new running direction of the own vehicle determined by the running direction processing unit. . More specific description will be given below.

For example, as shown in FIG. 1A, the travel control device CTS in the embodiment includes a radar device 1-1, an imaging device 1-2, a control processing unit 2, a storage unit 3, a power unit 4, and a braking unit. 5 and a steering unit 6 .

The radar device 1-1 is connected to the control processing unit 2, transmits a predetermined transmission wave under the control of the control processing unit 2, and receives a reflected wave of the transmission wave reflected by the target, thereby is detected and the position of the object is determined by measuring the direction of the object and the distance to the object. In this embodiment, the radar device 1-1 also obtains the relative velocity of the object with respect to the host vehicle VCs based on the Doppler shift of the reflected wave with respect to the transmitted wave for the detection of the preceding vehicle and the follow-up control. there is The radar device 1-1, for example, in this embodiment, as shown in FIG. It is provided at the front end and measures an object in front of the own vehicle in a predetermined first object range (range) R1. In one example, for example, the radar device 1-1 includes a transmitter that transmits a millimeter-wave transmission wave while scanning the first target range R1, and a receiver that receives a reflected wave of the transmission wave reflected by an object. and a signal processing unit that obtains the position of the object by obtaining the direction of the object and the distance to the object based on the transmitted wave and the reflected wave. The signal processing unit obtains the direction of the object from the transmission direction of the transmission wave in scanning the first target range R1, and determines the direction of the object based on the time difference between the transmission timing of the transmission wave and the reception timing of the reflected wave. A distance to an object is obtained (TOF (Time-Of-Flight) method). Note that the radar device 1-1 is not limited to such a configuration, and may be an appropriate type of radar device. For example, the radar device 1-1 may be a laser radar device using laser light instead of a millimeter wave band, and the radar device 1-1 may include a plurality of receiving antennas, and the plurality of receiving antennas may be It may be a device that obtains the direction of the object from the phase difference of the received reflected waves.

The radar device 1 - 1 outputs the position (direction, distance) and relative velocity of the object thus measured to the control processing unit 2 . When a plurality of objects are detected, the radar device 1-1 outputs each position (each direction and each distance) and each relative velocity of each of the plurality of objects to the control processing unit 2. FIG.

The imaging device 1-2 is a device that is connected to the control processing unit 2 and generates an image under the control of the control processing unit 2. FIG. The imaging device 1-2 is mounted on the own vehicle VCs so as to pick up an image in front of the own vehicle VCs (traveling direction) so as to include the road surface. For example, in the present embodiment, as shown in FIG. 1B, the image pickup device 1-2 is configured so that the ceiling surface (inner surface of the roof) in the vicinity of the windshield of the own vehicle VCs includes the road surface. The imaging direction (optical axis direction) is directed obliquely downward so as to capture an image of the front (traveling direction) in a predetermined second target range (angle of view) R2. In one example, for example, the imaging device 1-2 is an imaging optical system that forms an optical image of a subject (object) on a predetermined imaging plane, and is arranged with a light receiving surface aligned with the imaging plane, An area image sensor that converts the optical image of the subject into an electrical signal, and an image processing unit that performs image processing on the output of the area image sensor to generate image data representing the image of the subject. A digital camera. The imaging device 1 - 2 outputs the generated image to the control processing section 2 .

The power unit 4 is a device that is connected to the control processing unit 2 and generates power for driving (moving) the host vehicle VCs under the control of the control processing unit 2 . The power generated by the power unit 4 is transmitted to the drive wheels via a power transmission mechanism that transmits power, thereby rotating the drive wheels. The power unit 4 includes, for example, a prime mover such as an engine, a motor, and a hybrid device thereof, and accessories thereof.

The braking unit 5 is a device that is connected to the control processing unit 2 and applies braking force to the own vehicle VCs according to the control of the control processing unit 2 to decelerate the own vehicle VCs. The braking unit 5 can stop the own vehicle VCs as a result of decelerating the own vehicle VCs, and can also keep the own vehicle VCs stopped as a result of continuing to apply a braking force while the own vehicle VCs is stopped. The braking unit 5 includes, for example, brake devices such as disc brakes and regenerative brakes, and accessories thereof.

The steering unit 6 is a device that is connected to the control processing unit 2 and that steers the host vehicle VCs under the control of the control processing unit 2 . The steering section 6 includes a steering device for changing the direction of the steered wheels of the own vehicle VCs and its accessories.

By controlling the power section 4 and the braking section 5 respectively, the acceleration of the own vehicle VCs is adjusted, and the speed (vehicle speed) of the own vehicle VCs is adjusted. By controlling the steering unit 6, the traveling direction of the host vehicle VCs is adjusted.

The storage unit 3 is a circuit that is connected to the control processing unit 2 and stores various predetermined programs and various predetermined data under the control of the control processing unit 2 . The various predetermined programs include, for example, a control program for controlling each section 1-1, 1-2, 3 to 6 of the traveling control device CTS according to the function of each section, and a detection program by the radar device 1-1. A preceding vehicle processing program for obtaining the direction of the preceding vehicle VCp based on the position (direction, distance) of the object measured and the image generated by the imaging device 1-2, and the direction of the preceding vehicle VCp (preceding vehicle direction). and the traveling direction of the own vehicle VCs, while along the traveling direction processing program for obtaining the new traveling direction of the own vehicle CVs, and the traveling direction of the new own vehicle VCs obtained by the traveling direction processing program, leading It includes a control processing program such as a follow-up control program for controlling travel of the own vehicle VCs so as to follow the vehicle VCp. The various predetermined data include data necessary for executing each program, such as a rule for setting the third position on the arc (constant α, which will be described later). The storage unit 3 includes, for example, a ROM (Read Only Memory) that is a nonvolatile memory element, an EEPROM (Electrically Erasable Programmable Read Only Memory) that is a rewritable nonvolatile memory element, and the like. The storage unit 3 includes a RAM (Random Access Memory) or the like that serves as a so-called working memory of the control processing unit 2 that stores data generated during execution of the predetermined program.

The control processing unit 2 controls each unit 1-1, 1-2, 3 to 6 of the cruise control device CTS according to the function of each unit, and causes the vehicle VCs to follow the preceding vehicle VCp ahead of the own vehicle VCs. A circuit for controlling the running of the vehicle VCs. The control processing unit 2 is configured including, for example, a CPU (Central Processing Unit) and its peripheral circuits. The control processing unit 2 functionally includes a control unit 21, a preceding vehicle processing unit 22, a traveling direction processing unit 23, and a follow-up control unit 24 by executing the control processing program.

The control unit 21 controls each unit 1-1, 1-2, 3 to 6 of the cruise control device CTS according to the function of each unit, and controls the overall control of the cruise control device CTS.

The preceding vehicle processing unit 22 obtains the direction of the preceding vehicle VCp based on the position (direction, distance) of the object detected and measured by the radar device 1-1 and the image generated by the imaging device 1-2. be. More specifically, in the present embodiment, the preceding vehicle processing unit 22 uses the position (direction, distance) of the object detected and measured by the radar device 1-1 and the image generated by the imaging device 1-2. Based on this, the second position of the preceding vehicle VCp is determined. First, the preceding vehicle processing unit 22 selects an object having a relative speed to the own vehicle VCs from among the objects detected by the radar device 1-1. Next, the preceding vehicle processing unit 22 determines whether or not the vehicle is captured in an image area of a predetermined size corresponding to the position of the selected object in the image generated by the imaging device 1-2. . For example, the preceding vehicle processing unit 22 determines whether the vehicle is reflected in the image area by determining whether a predetermined feature amount related to the vehicle is extracted from the image area. More specifically, for example, an edge is extracted from the image region by an edge filter, a straight line is extracted from the extracted edge by Hough transform of the straight line, and a rectangle formed by the extracted straight line is extracted as the feature amount. It is determined whether or not Further, for example, a template representing a vehicle is prepared in advance, and the preceding vehicle processing unit 22 performs template matching on the image area to determine whether the vehicle is extracted or not. determine whether or not Further, for example, a machine learning model (for example, a convolutional neural network model (CNN model), etc.) that has undergone machine learning (for example, deep learning, etc.) to extract a vehicle is prepared in advance, and the preceding vehicle processing unit 22 extracts the vehicle from the image area. It is determined whether or not the vehicle is captured in the image area based on whether or not the vehicle is extracted by the machine learning model. Then, if the result of the determination is that a vehicle is reflected in the image area, the preceding vehicle processing unit 22 sets the selected object as the preceding vehicle VCp, and sets the selected object as the preceding vehicle VCp. is the second position of the preceding vehicle VCp (the direction and distance of the object) measured in .

In this manner, the preceding vehicle processing unit 22 obtains the direction, in this embodiment, the position of the preceding vehicle VCp based on the measurement result of the radar device 1-1 and the generated image of the imaging device 1-2. It is preferable that the first target range R1 of the device 1-1 is at least horizontally included in the second target range R2 of the imaging device 1-2 (R1≦R2 in the horizontal direction).

The traveling direction processing unit 23 obtains a new traveling direction of the own vehicle CVs between the direction of the preceding vehicle VCp (preceding vehicle direction) and the traveling direction of the own vehicle VCs. Note that the direction of the preceding vehicle VCp is not necessarily along the line passing through the center axis of the preceding vehicle VCp in the longitudinal direction of the vehicle. For example, the direction of the preceding vehicle VCp is the direction of the preceding vehicle VCp as seen from the own vehicle VCs, the direction of the movement direction of the preceding vehicle VCp estimated from the detection point detected by the radar device 1-1, and the like.

More specifically, in the present embodiment, first, as shown in FIG. 2A, the traveling direction processing unit 23 sets the first position Ps of the own vehicle VCs as the origin (0, 0), and calculates the traveling direction of the own vehicle VCs. is set as the X axis, and the vehicle width direction of the own vehicle VCs is set as the Y axis. A circle (auxiliary circle) CR passing through each of the second positions Pp is obtained. More specifically, as shown in FIG. 2B, the coordinate values of the second position Pp of the preceding vehicle VCp are (x, y), the radius of the auxiliary circle CR is R, and the point with coordinate values (0, y) is Pa and Pb is the intersection of the auxiliary circle CR and the Y-axis that is not at the first position (origin) Ps. Then, from the right triangle PsPpPb and the right triangle PaPpPb having the side PpPb in common, the radius R of the auxiliary circle CR is given by ( x ² +y ² )/(2y), and the auxiliary circle CR is a circle with center point Pc(0, R) and radius R=(x ² +y ² )/(2y). Next, as shown in FIG. 3, the traveling direction processing unit 23 moves from the first position Ps of the own vehicle VCs on the auxiliary circle CR toward the traveling direction of the own vehicle VCs to the second position Pp of the preceding vehicle VCp. A third position Pt is set on the arc AR of . As can be seen from FIG. 3, the arc AR can be inferred to have a shape that reflects the travel locus of the preceding vehicle VCp. The third position Pt is set in accordance with appropriately defined rules in advance. For example, when the coordinate value of the third position Pt is (x', y'), the X coordinate value x' of the third position Pt is the constant α of the X coordinate value x at the second position Pp of the preceding vehicle VCp. (x'=α·x, 0<α<1), and the Y coordinate value y' of the third position Pt is obtained by substituting x'=α·x into the formula representing the auxiliary circle CR. be done. The constant α is appropriately set to, for example, 0.3, 0.5, 0.7, or the like. FIG. 3 shows the third position Pt(x', y') when the constant α is 0.5. Then, as shown in FIG. 4, the traveling direction processing unit 23 determines the line segment PsPt connecting the first position Ps of the vehicle VCs and the set third position Pt from the first position Ps of the vehicle VCs to the third position Ps. The direction DRs toward the position Pt is set as the new running direction of the host vehicle.

That is, the traveling direction processing unit 23 uses the first position Ps of the own vehicle VCs as the origin, the traveling direction of the own vehicle VCs as the X axis, and the vehicle width direction of the own vehicle VCs as the Y axis. In a circle (auxiliary circle) CR having a center point Pc on the Y-axis and passing through a first position Ps of the host vehicle VCs and a second position Pp of the preceding vehicle VCp, when a system is set, A third position Pt is set on an arc AR from a first position Ps of the own vehicle VCs to a second position Pp of the preceding vehicle VCp toward the traveling direction of the own vehicle VCs (positive side of the X axis). , the direction DRs of the line segment PsPt connecting the first position Ps of the own vehicle VCs and the set third position Pt toward the third position Pt from the first position Ps of the own vehicle VCs is defined as the new direction DRs of the own vehicle VCs. It is the running direction of the vehicle.

The follow-up control unit 24 controls travel of the own vehicle VCs so that it follows the preceding vehicle VCp while following the new travel direction of the own vehicle determined by the travel direction processing unit 23 . More specifically, for example, in the present embodiment, the follow-up control unit 24 sets the third position Pt obtained by the traveling direction processing unit 23 as the target position, and the first position Ps and the third position Pt of the own vehicle VCs. and the steering angle change amount and vehicle speed change amount (acceleration change amount) in one control cycle in the control cycle of the follow-up running control that is repeatedly executed is defined as the host vehicle VCs and the preceding vehicle VCp, the distance between them, and the distance (target distance) between the first position Ps and the third position Pt of the own vehicle VCs. and control at least one of the power unit 4 and the braking unit 5 so as to obtain the obtained vehicle speed change amount (acceleration change amount). For each of these steering angle change amount and vehicle speed change amount (acceleration change amount), for example, a relational expression or a lookup table representing the relationship between them and the relative speed, the inter-vehicle distance, and the target distance is created in advance and stored in a storage unit. 3, and obtained using the relational expression and the lookup table.

In the cruise control device CTS having such a configuration, the radar device 1-1, the imaging device 1-2, and the preceding vehicle processing unit 22 of the control processing unit 2 determine the direction of the preceding vehicle preceding the own vehicle with respect to the own vehicle. It corresponds to an example of a measuring unit that measures the direction of the preceding vehicle, and further measures the distance between the own vehicle and the preceding vehicle to determine the second position of the preceding vehicle relative to the first position of the own vehicle. It corresponds to an example of a measuring unit that measures a position.

Next, the operation of this embodiment will be described. FIG. 5 is a flowchart showing the operation of follow-up running control in the running control device. FIG. 6 is a diagram for explaining one effect of the travel control device.

When the host vehicle VCs starts operating and a switch (not shown) for turning on/off the follow-up control is turned on, the cruise control device CTS initializes necessary parts and starts operating. By executing the control processing program, the control processing unit 2 is functionally configured with a control unit 21 , a preceding vehicle processing unit 22 , a traveling direction processing unit 23 and a follow-up control unit 24 . Then, the control processing unit 2 operates as follows in one control cycle of the follow-up cruise control that is repeatedly executed at predetermined time intervals, thereby causing the preceding vehicle VCp that precedes the own vehicle VCs. The running of the own vehicle VCs is controlled so as to follow the .

In FIG. 5, the control processor 2 first extracts the preceding vehicle VCp and measures its second position Pp (S1). More specifically, the control processing unit 2 acquires the position (direction, distance) of the object from the radar device 1-1, acquires the image from the imaging device 1-2, and the preceding vehicle processing unit 22 acquires an image from them. The second position Pp of the preceding vehicle VCp is obtained by performing the processing as described above. At this time, the control processing unit 2 sets the relative speed to the object measured by the radar device 1-1 as the relative speed to the preceding vehicle VCp.

Next, the control processing unit 2 uses the traveling direction processing unit 23 to generate an offset (preceding It is determined whether or not the Y coordinate value y) of the vehicle VCp is equal to or less than a predetermined offset threshold value (OS threshold value) set in advance (S2). If the distance (offset) between the host vehicle VCs and the preceding vehicle VCp in the vehicle width direction is small, it is impossible to form the auxiliary circle CR that can perform the follow-up running control with accuracy according to specifications. Processing S2 is executed. From this point of view, the OS threshold is appropriately set in advance to, for example, 10 cm, 20 cm, 30 cm, or the like. As a result of this determination, if the offset y is equal to or less than the OS threshold (Yes), the control processing unit 2 terminates the current control cycle. If the threshold value is exceeded, No), the control processing unit 2 next executes processing S3.

In this process S3, the control processing unit 2 causes the traveling direction processing unit 23 to perform the assisting operation based on the first position Ps of the host vehicle VCs and the second position Pp of the preceding vehicle VCp as described above with reference to FIG. Find the circle CR.

Following this processing S3, the control processing unit 2 causes the traveling direction processing unit 23 to set the third position Pt on the arc AR of the auxiliary circle CR obtained in processing S3, as described above with reference to FIG. (S4).

Following this process S3, the control processing unit 2 performs follow-up running control based on the third position Pt set in this process S4 (S5), and ends the current control cycle. More specifically, the control processing unit 2 first causes the traveling direction processing unit 23 to determine the direction DRs of the line segment PsPt from the first position Ps to the third position Pt as described above with reference to FIG. , the new running direction of the own vehicle, and the follow-up control unit 24 controls the running of the own vehicle VCs so as to follow the preceding vehicle VCp while following the new running direction of the own vehicle. In this follow-up travel control, as described above, the follow-up control unit 24 sets the third position Pt as the target position, sets the line segment PsPt as the travel route, and sets the steering angle change amount in one control cycle. and a vehicle speed change amount (acceleration change amount) are obtained, the steering unit 6 is controlled so as to achieve the obtained steering angle change amount, and the power unit 4 and At least one of the braking units 5 is controlled.

Such control is repeatedly executed until follow-up running control is turned off, and follow-up running control is performed.

As described above, the cruise control device CTS and the cruise control method implemented in the cruise control device CTS in the embodiment can set a new running direction of the own vehicle VCs between the direction of the preceding vehicle VCp and the running direction of the own vehicle VCs. Since it is possible to set the traveling direction of the follow-up travel control for the preceding vehicle VCp by the arithmetic processing of obtaining, the follow-up travel control can be performed with a simpler calculation.

As described above, it can be inferred that the arc AR in the auxiliary circle CR passing through the first position Ps of the own vehicle VCs and the second position Pp of the preceding vehicle VCp has a shape reflecting the travel locus of the preceding vehicle VCp. Therefore, the cruise control device CTS and the cruise control method control the direction from the first position Ps to the third position Pt of the line segment PsPt connecting the first position Ps of the own vehicle VCs and the third position Pt on the arc AR. , the traveling direction of the new vehicle VCs, so that the traveling direction of the new vehicle VCs can be determined in consideration of the traveling locus of the preceding vehicle VCp, as shown in FIG. In particular, when the preceding vehicle VCp travels according to the curve of the lane, the travel control device CTS and the travel control method can determine the travel direction of the new host vehicle VCs in consideration of the curve of the lane. When the lane is curved, as shown in FIG. 6, if a line segment PsPp connecting the first position Ps of the own vehicle VCs and the preceding vehicle VCp is set in the travel route, the lane However, in this embodiment, the cruise control device CTS and the cruise control method set the third position Pt as the target position of the vehicle. , the line segment PsPt connecting the first position Ps of the own vehicle VCs and the third position (target position of the own vehicle VCs) Pt can be set as the travel route, so that the deviation of the own vehicle VCs from the lane can be reduced.

In the above-described embodiment, the third position Pt set on the arc is set according to a rule set appropriately in advance, but is not limited to this, and is adjusted and set on the arc AR can be

For example, the traveling direction processing unit 23 may adjust the third position Pt based on the radius of curvature of the arc AR and set it on the arc AR. The travel control device CTS having such a travel direction processing unit 23 adjusts the third position Pt based on the radius of curvature of the arc AR. Can determine the direction of travel. More specifically, for example, when the radius of curvature of the arc AR is greater than a predetermined threshold (first threshold) Th1, the traveling direction processing unit 23 moves the third position Pt from the central position of the arc AR. The third position Pt is set to the second position side of the preceding vehicle VCp, and when the curvature radius of the arc AR matches the threshold value Th1, the third position Pt is set to the center position of the arc AR, and When the radius of curvature is smaller than the threshold value Th1, the above-mentioned A third position Pt is adjusted and set on the arc AR. Further, for example, when the curvature radius of the arc AR is equal to or greater than a predetermined threshold value Th1, the traveling direction processing unit 23 moves the third position Pt from the center position of the arc AR to the second position side of the preceding vehicle VCp. and when the radius of curvature of the arc AR is less than the threshold value, the arc The third position Pt is adjusted and set on the arc AR based on the radius of curvature of AR. Since the travel control device CTS having such a travel direction processing unit 23 adjusts the third position Pt based on the radius of curvature of the arc AR as in each of the cases described above, the travel is more along the curve of the lane. The direction of travel of the new host vehicle VCs can be determined.

In this case, instead of the radius of curvature of the arc AR, the radius of curvature of the lane on which the vehicle VCs travels may be used. For example, from the image of the imaging device 1-2, a pair of lane boundary lines (lane markers) are extracted by a known conventional means, and the radius of curvature of the lane specified by the extracted pair of lane boundary lines (eg average radius of curvature of the lane from the own vehicle to the preceding vehicle, etc.) is obtained.

Further, for example, the cruise control device CTS further includes a speed measuring unit 7 that measures the speed of the own vehicle VCs, as indicated by the dashed line in FIG. The speed measurement unit 7 is connected to the control processing unit 2 , measures the speed (vehicle speed) of the own vehicle VCs under the control of the control processing unit 2 , and outputs the measured speed of the own vehicle VCs to the control processing unit 2 . The traveling direction processing unit 23 may adjust the third position Pt based on the speed of the own vehicle VCs measured by the speed measuring unit 7 and set it on the arc AR. The travel control device CTS having such a travel direction processing unit 23 adjusts the third position Pt based on the speed of the host vehicle VCs. It is possible to reduce bulging outward and inward movement. More specifically, for example, when the speed of the own vehicle VCs measured by the speed measuring unit 7 is greater than a predetermined second threshold value Th2, the traveling direction processing unit 23 moves the third position Pt to the arc When the speed of the host vehicle VCs measured by the speed measuring unit 7 is set to the second position side of the preceding vehicle VCp from the center position of the AR, the third position Pt is set to the central position of the arc AR, and when the speed of the own vehicle VCs measured by the speed measuring unit 7 is smaller than the second threshold Th2, the third position Pt is set to the central position of the arc AR The third position Pt is adjusted based on the speed of the vehicle VCs measured by the speed measuring unit 7 so as to be set on the first position side of the vehicle VCs and set on the arc AR. Further, for example, when the speed of the own vehicle VCs measured by the speed measuring unit 7 is equal to or greater than a predetermined second threshold value Th2, the traveling direction processing unit 23 moves the third position Pt from the center position of the arc AR. When the speed of the own vehicle VCs measured by the speed measuring unit 7 is less than the second threshold value Th2, the third position Pt is set to the second position side of the preceding vehicle VCp, and the third position Pt is set to the center of the arc AR. The third position Pt is adjusted based on the speed of the own vehicle VCs measured by the speed measuring unit 7 so as to be set on the first position side of the own vehicle VCs from the position and set on the arc AR. The travel control device CTS having such a travel direction processing unit 23 can detect the speed of the own vehicle VCs when the speed of the own vehicle VCs is greater than the second threshold value Th2 or when the preceding vehicle VCp is steered to change the travel direction. is greater than or equal to the second threshold value Th2, the third position Pt is set to the second position side of the preceding vehicle VCp from the center position of the arc AR, so that it is possible to suppress outward bulging, and the own vehicle VCs is smaller than the second threshold Th2 or the speed of the own vehicle VCs is smaller than the second threshold Th2, the third position Pt is moved from the center position of the arc AR to the third position of the own vehicle VCs. Since it is set on the 1 position side, it is possible to suppress inward movement.

In the above-described embodiment, the moving object is detected from the measurement result of the radar device 1-1, and the preceding vehicle VCp is detected by determining whether or not the moving object is a vehicle from the image of the imaging device 1-2. Although the preceding vehicle BCp is detected and the position of the preceding vehicle BCp is obtained, the preceding vehicle processing unit 22 may obtain the second position of the preceding vehicle VCp as follows. First, the preceding vehicle processing unit 22 obtains the image area of the preceding vehicle VCp from the image generated by the imaging device 1-2. For example, a predetermined feature amount related to a vehicle is extracted from an image, and an image area having the feature amount is extracted as an image area of the preceding vehicle VCp (for example, an edge is extracted from the image by an edge filter, and the extracted A straight line is extracted from the edge obtained by Hough transform of the straight line, a rectangle formed by the extracted straight line is extracted as the feature amount, and the extracted rectangular area is extracted as the image area of the preceding vehicle VCp). Further, for example, a template representing a vehicle is prepared in advance, and an image area correlated with the template is extracted from the image as an image area of the preceding vehicle VCp by template matching. Further, for example, a machine learning model that is machine-learned so as to extract a vehicle is prepared in advance, and the image region of the preceding vehicle VCp is extracted from the image by the machine learning model. Next, the preceding vehicle processing unit 22 selects, as the preceding vehicle VCp, an object corresponding to the obtained image area from among the objects detected by the radar device 1-1. Then, the preceding vehicle processing unit 22 sets the position (direction and distance of the object) of the selected object measured by the radar device 1-1 as the second position of the preceding vehicle VCp.

Further, in the above-described embodiment, the measurement unit that measures the direction of the preceding vehicle that precedes the own vehicle as the preceding vehicle direction with respect to the own vehicle includes the radar device 1-1, the imaging device 1-2, and the Although the preceding vehicle processing unit 22 is included in the configuration, the present invention is not limited to this and may be configured as appropriate.

For example, the measuring unit includes a radar device, detects a moving object existing in front of the host vehicle VCs based on the Doppler shift measured by the radar device, and defines the detected moving object as the preceding vehicle VCp. The direction DRp of the preceding vehicle (moving object) VCp measured by the radar device may be output to the control processing unit 2 . As shown in FIG. 4, the running direction processing unit 23 of the control processing unit 2 determines a distance between the direction DRp of the preceding vehicle VCp output from the radar device and the current running direction (X-axis direction) of the host vehicle VCs. , to determine the direction of travel of the new host vehicle VCs. For example, the new traveling direction of the own vehicle _VCs is determined by the traveling direction of the own vehicle VCs ( (2/3)×θ ₀ , (1/2)×θ ₀ , and (1/3)×θ ₀ with respect to the X-axis direction). When the angle between the running direction and the current running direction (X-axis direction) of the own vehicle VCs is θs, θs=β·θ ₀ , β is 2/3, 1/2, 1/3, etc. A constant set appropriately in advance (0<β<1)).

Further, for example, the measurement unit may be a stereo camera provided with a pair of imaging devices that are spaced apart by a predetermined base line length and arranged such that their optical axes are parallel. Such a stereo camera extracts an image area of the preceding vehicle from one of the images generated by one of the pair of imaging devices, and uses the extracted image area of the preceding vehicle as a template to capture the pair of images. The parallax is obtained by extracting the image area of the preceding vehicle from the other image by template matching from the other image of the device, and the position of the preceding vehicle is determined based on the parallax obtained by the so-called triangulation principle. Find (direction and distance).

In the above-described embodiment, when the computational load is relatively low, instead of the follow-up travel control that finds a new travel direction of the own vehicle VCs between the direction of the preceding vehicle VCp and the travel direction of the own vehicle BVCs, Follow-up travel control may be executed in which the travel route of the own vehicle is calculated along the travel locus of the preceding vehicle.

Although the present invention has been adequately and fully described above through embodiments with reference to the drawings in order to express the present invention, modifications and/or improvements to the above-described embodiments can easily be made by those skilled in the art. It should be recognized that it is possible. Therefore, to the extent that modifications or improvements made by those skilled in the art do not depart from the scope of the claims set forth in the claims, such modifications or improvements do not fall within the scope of the claims. is interpreted to be subsumed by

CTS: travel control device VCs own vehicle VCp preceding vehicle Ps first position Pp of own vehicle VCs second position Pt of preceding vehicle VCp third position DRs new traveling direction CR of own vehicle VCs auxiliary circle AR arc 1-1 radar device 1 -2 Imaging device 2 Control processing unit 3 Storage unit 4 Power unit 5 Braking unit 6 Steering unit 7 Speed measurement unit 21 Control unit 22 Leading vehicle processing unit 23 Traveling direction processing unit 24 Following control unit

Claims (6)

a measurement unit that measures a direction of a preceding vehicle that precedes the own vehicle as a preceding vehicle direction with respect to the own vehicle;
a traveling direction processing unit for obtaining a new traveling direction of the own vehicle between the preceding vehicle direction measured by the measuring unit and the traveling direction of the own vehicle;
a follow-up control unit that controls travel of the own vehicle so as to follow the preceding vehicle while following the new travel direction of the own vehicle determined by the travel direction processing unit;
The measurement unit further measures a second position of the preceding vehicle with respect to the first position of the own vehicle by measuring a distance between the own vehicle and the preceding vehicle ;
When the traveling direction processing unit sets an XY orthogonal coordinate system having the first position of the own vehicle as the origin, the traveling direction of the own vehicle as the X axis, and the vehicle width direction of the own vehicle as the Y axis, , a circle having a center point on the Y-axis and passing through the first position of the own vehicle and the second position of the preceding vehicle, from the first position of the own vehicle to the running direction of the own vehicle. (d) setting a third position on an arc extending to the second position of the preceding vehicle; and forming a line connecting the first position of the own vehicle and the set third position from the first position of the own vehicle to the above-described third position; setting the direction toward the third position as the new traveling direction of the own vehicle ;
travel control device. The traveling direction processing unit adjusts the third position based on the radius of curvature of the arc and sets it on the arc.
The traveling control device according to claim 1 . When the curvature radius of the arc is greater than a predetermined threshold value, the traveling direction processing unit sets the third position to the second position side of the preceding vehicle from the center position of the arc, and is equal to the threshold value, the third position is set to the center position of the arc, and if the radius of curvature of the arc is smaller than the threshold value, the third position is set to the center position of the arc. adjusting the third position based on the radius of curvature of the arc so as to set it on the first position side of the vehicle, and setting it on the arc;
The traveling control device according to claim 2 . Further comprising a speed measuring unit that measures the speed of the own vehicle,
The traveling direction processing unit adjusts the third position based on the speed of the own vehicle measured by the speed measuring unit and sets it on the arc.
The traveling control device according to claim 1 . When the speed of the host vehicle measured by the speed measuring unit is greater than a second threshold value, the traveling direction processing unit sets the third position to the second position side of the preceding vehicle from the center position of the arc. , and when the speed of the own vehicle measured by the speed measuring unit matches the second threshold value, the third position is set to the center position of the arc, and the speed measured by the speed measuring unit is set to When the speed of the own vehicle is smaller than the second threshold value, the speed of the own vehicle measured by the speed measuring unit is set so that the third position is set closer to the first position of the own vehicle than the center position of the arc. adjusting the third position to set it on the arc based on the velocity of
The traveling control device according to claim 4 . a measuring step of measuring a direction of a preceding vehicle that precedes the own vehicle as a preceding vehicle direction with respect to the own vehicle;
a traveling direction processing step of obtaining a new traveling direction of the own vehicle between the preceding vehicle direction measured in the measuring step and the traveling direction of the own vehicle;
a follow-up control step of controlling travel of the own vehicle so as to follow the preceding vehicle while following the new travel direction of the own vehicle obtained in the travel direction processing step;
The measuring step further measures a second position of the preceding vehicle relative to the first position of the own vehicle by measuring a distance between the own vehicle and the preceding vehicle ;
In the traveling direction processing step, when an XY orthogonal coordinate system is set with the first position of the own vehicle as the origin, the traveling direction of the own vehicle as the X axis, and the vehicle width direction of the own vehicle as the Y axis. , a circle having a center point on the Y-axis and passing through the first position of the own vehicle and the second position of the preceding vehicle, from the first position of the own vehicle to the running direction of the own vehicle. (d) setting a third position on an arc extending to the second position of the preceding vehicle; and forming a line connecting the first position of the own vehicle and the set third position from the first position of the own vehicle to the above-described third position; setting the direction toward the third position as the new traveling direction of the own vehicle ;
travel control method.

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