JP5206740B2 - Road shape detection device - Google Patents

Description

  The present invention relates to a road shape detection device that is mounted on a vehicle and detects the shape of a road on which the host vehicle travels.

  As the above-described road shape detection device, a technique for estimating the curve start position using map data of the navigation device and improving the accuracy of detecting the position of the host vehicle using the detection result by the radar is known. (For example, refer to Patent Document 1).

JP 2010-030403 A

  However, the map data possessed by the navigation device generally includes a large number of node data representing positions and a large number of link data connecting the nodes, and a sufficient amount of data for detecting the presence or absence of a curve. However, in order to detect the start position of the curve, the amount of data is often insufficient and insufficient. For this reason, in the said road shape detection apparatus, there existed a problem that possibility that a curve start position cannot be detected correctly is high.

  Accordingly, in view of such problems, it is an object of the present invention to provide a technology that can contribute to improvement in detection accuracy of a curve start position in a road shape detection device that is mounted on a vehicle and detects the shape of a road on which the host vehicle travels. The purpose.

  In the road shape detection apparatus configured to achieve such an object, the first start position estimating means includes a plurality of detection points obtained by receiving reflected waves by irradiating electromagnetic waves in the traveling direction of the host vehicle. Is used to estimate the curve start position in the traveling direction of the host vehicle (hereinafter referred to as “first start position”). On the other hand, the second start position estimating means includes node data including a large number of nodes representing the position, map data capable of expressing a road shape by link data including a large number of links connecting the nodes, the current location of the host vehicle, and A curve start position in the traveling direction of the host vehicle (hereinafter referred to as “second start position”) is estimated based on the direction of the host vehicle. The position determining means determines whether or not the distance between the first start position and the second start position is within an error range assumed when the second start position estimating means estimates the second start position. (Claim 1).

  According to such a road shape detection device, since it is determined whether or not the distance between the first start position and the second start position is within an error range assumed when estimating the second start position. By using this determination result, it is possible to specify which of the first start position and the second start position has higher detection accuracy.

Therefore, in the present invention, it is possible to contribute to improvement of the detection accuracy of the curve start position. In addition, if the start position identified as having high detection accuracy is set as the curve start position, the detection accuracy of the curve start position can be improved.
By the way, if a plurality of nodes included in the map data are arranged on a straight line in the traveling direction of the host vehicle, and there is a node that deviates from the straight line in the forward traveling direction, it can be estimated that there is a curve start position in the vicinity. Whether or not an accurate curve start position can be estimated from map data depends on the interval (density) of a plurality of nodes. That is, it represents the accuracy of the map data when estimating the curve start position where the node interval is accurate.
Therefore, in the road shape detection device of the present invention, an error for setting an error range used when determining whether or not to specify the first start position as the curve start position according to the interval of the nodes included in the map data. A range setting means is provided.
According to such a road shape detection device, it is possible to change a criterion (error range) for determining whether or not the first start position is set as the curve start position in accordance with the estimation accuracy of the curve start position in the map data.
When the present invention is dependent on the invention described in claim 6, the curvature range may be set according to the interval of the nodes included in the map data.
In the road shape detection device, the curve start position exists within a range in which a reflected wave by irradiating an electromagnetic wave in the traveling direction of the host vehicle can be received based on the current location of the host vehicle and map data. When the presence determination unit and the presence determination unit determine whether the curve start position does not exist within the range in which the reflected wave can be received, the first start position estimation unit and the second start And a prohibition unit that prohibits processing by at least one of the position estimation unit and the position determination unit (Claims 2 and 3).
According to such a road shape detection device, since any process is prohibited when the curve start position does not exist within the range in which the reflected wave can be received, the processing load at this time can be reduced. In addition, it is possible to prevent detection points different from road shapes such as road surfaces and buildings in a gradient section or the like from being used when specifying a curve start position. In the present invention, processing may be prohibited even while traveling in a curve.

By the way, in the road shape detection device, an apparatus outside the road shape detection device may specify the curve start position. However, in order for the road shape detection device to specify the curve start position, position determination is performed. If the distance between the first start position and the second start position is determined to be within the error range by means, optionally comprising a specifying means for specifying a first start position as the curve starting position (claim 4) . In this case, the specific means, if not specified first start position as the curve starting position, even identify the second start position as the curve starting position Good (claim 5).

According to such a road shape detection apparatus, the curve start position can be specified according to the determination result by the position determination means.
In the road shape detection apparatus, curvature estimation means for estimating a curvature of a curve in the traveling direction of the host vehicle (hereinafter referred to as “first curvature”) based on a plurality of detection points, map data, and the map data A curvature range calculating means for calculating a curvature range (hereinafter referred to as “curvature range”) that is estimated to be within the curvature of the actual curve in the traveling direction of the host vehicle, based on error information relating to the error included in the vehicle; Curvature determining means for determining whether or not the first curvature is within the curvature range, and the specifying means has a distance between the first start position and the second start position within the error range by the position determination means. it is determined, and if the first curvature is determined to be within the curvature range by the curvature determining unit may be configured to identify a first start position as the curve starting position (claim 6).

  According to such a road shape detection device, whether or not the first start position is set as the curve start position is determined depending on whether or not the curvature of the curve estimated from the plurality of detection points is within the curvature range. It is possible to prevent the curve start position from being specified using a detection point having a curvature far from the curvature of the curve. Therefore, the curve start position can be specified accurately.

The curvature range is a value indicating the high accuracy of the map data, and this value may be a fluctuation value set for each curve or a fixed value.
Further, in the road shape detection device, each means constituting the road shape detection device repeatedly performs processing to be performed by itself at a predetermined cycle, and the specifying means uses the position determination means to perform the first start position and the second start position. If the distance from the position is within the error range, the first start position may be specified as the curve start position only when the reference number of times set to a plurality of times is determined ( claim 7 ).

According to such a road shape detection device, the first start position is specified as the curve start position only when it is determined a plurality of times, so that the influence of noise or the like can be eliminated .

Further, the road shape detection apparatus may include at least an output means for outputting a determination result by the position determination means (claim 8).
According to such a road shape detection device, the curve start position can be specified in an external device that has received the determination result.

1 is an explanatory diagram showing a schematic configuration of a driving support system 1. FIG. In embodiment, it is a schematic diagram which shows the area | region which irradiates a laser beam. It is the flowchart (a) which shows a radar process, and the flowchart (b) which shows a start determination process. It is a flowchart which shows a selection process. It is a flowchart which shows selection condition calculation processing. It is a bird's-eye view which shows typically the processing which presumes a curve start position.

Embodiments according to the present invention will be described below with reference to the drawings.
[Configuration of this embodiment]
FIG. 1 is an explanatory diagram showing a schematic configuration of the driving support system 1 of the present embodiment, and FIG. 2 is a schematic diagram showing a region where laser light is irradiated. The driving support system 1 is mounted on a vehicle such as a passenger car, for example, and includes a radar device 10 (road shape detection device), sensors 20, a vehicle control unit 30, a navigation device 40, and the like as shown in FIG. Yes. The radar apparatus 10 includes a radar control unit 11, a scanning drive unit 12, and an optical unit 13.

  The radar control unit 11 is configured as a well-known microcomputer including a CPU, a ROM, a RAM, and the like, and executes various processes such as a radar process described later according to a program stored in the ROM. The radar control unit 11 may be configured by hardware such as a circuit.

  The scanning drive unit 12 is configured as an actuator such as a motor, for example, and is configured to be able to direct the optical unit 13 in an arbitrary direction in the horizontal direction and the vertical direction in response to a command from the radar control unit 11. Yes. The scanning drive unit 12 drives the optical unit 13 so that scanning for one cycle can be performed every time a scanning start signal is received from the radar control unit 11.

  The optical unit 13 emits laser light in response to a command from the radar control unit 11, and laser light from the light emitting unit 14 (indicated by a solid line arrow in FIG. 1) is reflected on the object 50. And a light receiving unit 15 that receives reflected waves (indicated by broken arrows in FIG. 1).

  As a result, the scanning drive unit 12 may be configured so that the emission direction of the laser light from the light emitting unit 14 is changed to the same direction as the direction in which the light receiving unit 15 can receive the reflected light. For example, instead of the optical unit 13, the scanning drive unit 12 may be configured to drive a mirror that reflects laser light and reflected light in an arbitrary direction.

  In this case, the laser beam is scanned in the horizontal direction by rotating a mirror having a plurality of reflecting surfaces by the scanning drive unit 12 and the angles of the reflecting surfaces are set to different angles, so that the laser beam is also vertically aligned. A configuration for scanning while shaking light may be employed. Further, a mechanism for directing a mirror having one reflecting surface in an arbitrary direction may be employed.

  As described above, the radar apparatus 10 intermittently irradiates a predetermined area in an arbitrary direction around the host vehicle (in the present embodiment, the front in the traveling direction of the host vehicle) with laser light that is an electromagnetic wave while scanning. And it is comprised as a laser radar which detects the target ahead of the own vehicle as each detection point by receiving the reflected wave (reflected light), respectively.

  Here, in the radar apparatus 10 of the present embodiment, the radar control unit 11 scans the laser light emitted from the optical unit 13 within a predetermined region using the scanning drive unit 12 as described above. As shown in FIG. 2, the laser beam is irradiated intermittently at equal intervals (equal angles) while changing the range in which the laser beam is irradiated horizontally from the upper left corner to the upper right corner of this region. When reaching the upper right corner, the laser beam is irradiated again while changing the range in which the laser beam is irradiated from the region below the upper left corner by a predetermined angle to the right side in the horizontal direction.

  By repeating this operation, the radar apparatus 10 sequentially irradiates the entire region of the predetermined region with laser light. The radar apparatus 10 detects the position of the target (detection point) each time the laser beam is irradiated based on the timing at which the reflected wave is detected and the direction in which the laser beam is irradiated.

  Note that the direction in which the radar apparatus 10 is directed can be specified by dividing the entire region irradiated with the laser light into a matrix for each region irradiated with the laser light and assigning a number to each region. For example, as shown in FIG. 2, numbers are assigned in order from the left in the horizontal direction, and these numbers are called orientation numbers. Also, numbers are assigned in order from the top in the vertical direction, and these numbers are referred to as layer numbers.

  Next, the sensors 20 include a vehicle speed sensor that detects the traveling speed of the host vehicle, a rain sensor that detects weather around the vehicle, an illuminance sensor, and the like. Detection results by these sensors 20 are input to the radar control unit 11. Moreover, the detection result by the sensors 20 is also input to the navigation device 40 or the like as necessary.

  Next, the vehicle control unit 30 is configured as a well-known microcomputer including a CPU, ROM, RAM, etc., and controls the behavior of the host vehicle in accordance with a program stored in the ROM, etc. Various processes such as notification are performed. For example, when the vehicle control unit 30 receives a command from the radar apparatus 10 to perform driving support such as changing the behavior of the host vehicle (or urging the behavior to be changed), the vehicle control unit 30 sends a control signal corresponding to the command. What is necessary is just to make it output to any of a display apparatus, an audio | voice output apparatus, a braking device, a steering apparatus, etc.

  The navigation device 40 is a well-known navigation device, and includes node data including a large number of nodes representing positions, and map data capable of expressing a road shape by link data including a large number of links connecting the nodes. ing. The navigation device 40 receives radio waves from a GPS (Global Positioning System) satellite and performs known processing such as map matching to detect the current location of the host vehicle and the direction of the host vehicle, map data, and the like. And a function for displaying the current location of the vehicle in correspondence with each other.

  In addition, the navigation device 40 according to the present embodiment transmits map data of the traveling direction of the own vehicle (at least in a region detectable by the radar device 10) to the radar device 10 in response to a request from the radar device 10. It also has a function.

[Process of this embodiment]
In such a driving support system 1, for example, the following processing is performed. FIG. 3A is a flowchart showing a radar process executed by the radar control unit 11 of the radar apparatus 10, and FIG. 3B is a flowchart showing a start determination process executed by the radar control part 11 of the radar apparatus 10. 4 is a flowchart showing a selection process executed by the radar control unit 11 of the radar apparatus 10, and FIG. 5 is a flowchart showing a selection condition calculation process in the selection process.

  The radar processing is processing for measuring the distance to the object 50 in each irradiation direction while changing the irradiation direction of the laser light. This process is started, for example, when the power of the radar apparatus 10 is turned on, and thereafter, is executed every predetermined cycle (for example, every 100 ms).

  Specifically, as shown in FIG. 3A, first, the direction (azimuth number and layer number) for detecting the distance to the object is set (S110), and the irradiation direction of the laser light is directed to the set direction. The laser light is emitted from the light emitting unit 14 (S120). Then, distance measurement processing (S130) is performed.

  In this process, it is determined whether or not the reflected light of the laser beam can be detected by the light receiving unit 15, and if the reflected light can be detected, the distance to the object that reflected the laser beam according to the timing of receiving the reflected light. Is calculated. Then, the calculation result of the distance to the object is stored in a memory such as a RAM.

  Subsequently, it is determined whether or not to end scanning (S140). As to whether or not to end scanning, the light receiving unit 15 (light emitting unit 14) in the direction having the final azimuth number and layer number for detecting distance or luminance (for example, the direction in which the azimuth number and layer number take the maximum value). Judgment is made based on whether or not is directed.

If the scanning is not terminated (S140: NO), the processing from S110 onward is repeated. If the scanning is to be terminated (S140: YES), the radar process is terminated.
Next, the start determination process (FIG. 3B) will be described. This process is a process for setting whether to permit or prohibit the start of a selection process described later. This process is started, for example, when the power of the radar apparatus 10 is turned on, and thereafter, is executed every predetermined cycle (for example, every 500 ms). This processing is performed in parallel with the above-described radar processing and the like.

  In the start determination process, first, map data and host vehicle information in the traveling direction of the host vehicle are acquired from the navigation device 40 (S160). The own vehicle information acquired here corresponds to information on the current location of the own vehicle and information on the traveling direction of the own vehicle (the direction of the own vehicle).

  Subsequently, using the information acquired in the process of S160, it is determined whether or not the curve start position exists within the detection range by the radar apparatus 10 (S170: presence determination means, prohibition means). In this process, map data within a range about twice the detection range (for example, about 200 m) by the radar apparatus 10 is acquired, and there are a plurality of nodes serving as curve start positions within the detection range by the radar apparatus 10. Whether or not is detected. This process can be performed in the same manner as the process of S220 described later, but details of this process will be described in the process of S220.

  If the curve start position exists within the detection range of the radar apparatus 10 (S170: YES), the fact that the selection process described later is permitted is recorded in a memory such as a RAM (S180), and the start determination process is terminated. To do. If the curve start position does not exist within the detection range of the radar device 10 (S170: NO), the fact that the selection process described later is prohibited is recorded in a memory such as a RAM (S180), and the start determination is made. The process ends.

  Next, the selection process will be described. The selection process is a process of detecting a curve start position based on the radar device 10 and map data, and selecting a curve start position estimated to be probable from these. This process is performed at predetermined intervals (for example, every 100 ms) when, for example, the radar apparatus 10 is turned on and the fact that the selection process is permitted is recorded in a memory such as a RAM. The This processing is performed in parallel with the above-described radar processing and the like.

  In the selection process, as shown in FIG. 4, first, the curve start position (first start position) in the traveling direction of the host vehicle is estimated using the relative distances to a plurality of detection points by the radar apparatus 10 (S210). : First start position estimating means). Next, a curve start position (second start position) in the traveling direction of the host vehicle is estimated based on the map data, the current location of the host vehicle, and the direction of the host vehicle (S220: second start position estimating means).

  In these processes, it is detected that a plurality of detection points by the radar apparatus 10 and a plurality of nodes based on the map data are arranged on a straight line in the traveling direction of the host vehicle, and in this state, this node is further forward in the traveling direction. When a plurality of detection points or nodes existing at positions deviating from the straight line are detected, the position where the detection point or node deviating from the straight line first exists may be estimated as the curve start position. For example, in the process of S220, the map data 60 is composed of a large number of nodes 61 and a large number of links 62 connecting the nodes 61 as shown in FIG. The curve start position is detected.

  Subsequently, a range (error range) where an actual curve start position is estimated to exist based on the map data is set (S230: error range setting means, position determination means). In this processing, a point farthest from the own vehicle (point A in FIG. 6A) among a plurality of nodes arranged in a straight line is used as a reference, and within a predetermined distance from this point (FIG. 6A ) Is set as an estimated range.

  Subsequently, it is determined whether or not a curve start position estimated using a plurality of detection points by the radar apparatus 10 exists within the estimated range (S240: position determination means). If there is a curve start position estimated using a plurality of detection points by the radar apparatus 10 within this range (S240: YES), a selection condition calculation process (S250) is performed.

  The selection condition calculation process is a process for confirming whether or not the curve corresponding to the curve start position detected by the radar apparatus 10 is a curve that is actually detected. In this selection condition calculation process, as shown in FIG. 5, first, the curvature (first curvature) of the curve in the traveling direction of the host vehicle is estimated based on a plurality of detection points by the radar apparatus 10 (S410: curvature estimation means). .

  Then, the curvature (second curvature) of the curve in the traveling direction of the host vehicle is estimated based on the map data (particularly the positions of a plurality of nodes) (S420: curvature range calculation means). Thus, when estimating the 1st curvature and the 2nd curvature, Hough transform, a least squares method, etc. should just be used about a detection point and a node beyond a curve start position.

  Subsequently, a curvature range (curvature range) estimated to fit the curvature of the actual curve in the traveling direction of the host vehicle is calculated based on the map data and error information related to the error included in the map data (S430). . Here, as the error information, a value indicating the accuracy of the map data such as the density of a plurality of nodes constituting the curve (the number of nodes per unit distance) may be used.

  Subsequently, it is determined whether or not the first curvature is within the curvature range (S440: curvature determination means). If the first curvature is within the curvature range (S440: YES), the fact that the selection condition is satisfied is recorded in a memory such as a RAM (S450), and the selection condition calculation process is terminated.

If the first curvature is outside the curvature range (S440: NO), the fact that the selection condition is not satisfied is recorded in a memory such as a RAM (S460), and the selection condition calculation process is terminated.
When such selection condition calculation processing is completed, the process returns to FIG. 4 to determine whether or not the fact that the selection condition is satisfied is recorded in a memory such as a RAM (S260). If the selection condition is satisfied (S260: YES), the counter value is incremented (S270), and the process proceeds to S280 described later.

  Further, when there is no curve start position estimated using a plurality of detection points by the radar apparatus 10 within the range estimated in the process of S240 (S240: NO), and the selection condition is set in the process of S260. If not satisfied (S260: NO), it is determined whether a condition for clearing the counter value (counter clear condition) is satisfied (S310). Here, as the counter clear condition, for example, an arbitrary condition can be set, for example, when the counter value does not exceed the reference value within a certain time.

  If the counter clear condition is satisfied (S310: YES), the counter value is cleared (S320), and the process proceeds to S330. If the counter clear condition is not satisfied (S310: NO), the process immediately proceeds to S330.

  Incidentally, in the process of S280, it is determined whether or not the counter value is equal to or greater than a predetermined constant n (reference number, n is a value of 2 or more) (S280). That is, in the process of S280, in order to eliminate the case where the curve start position by the radar apparatus 10 is detected by the influence of noise or the like, it is determined whether or not the conditions of S240 and S260 are satisfied more than n times. Like to do.

  If the counter value is larger than the constant n (S280: YES), the curve start position by the radar apparatus 10 is selected (S290: specifying means), and the selected curve start position is output to the vehicle control unit 30 (S340). The process ends. On the other hand, if the counter value is equal to or smaller than the constant n (S280: NO), the curve start position estimated based on the map data is selected (S330: specifying means), and based on the curve start position by the radar apparatus 10 and the map data. The selected curve start position is output to the vehicle control unit 30 together with information on which one of the curve start positions is selected (S340: output means), and the selection process is terminated.

  When such a selection process is performed, the curve start position (within the range [1] in FIG. 6 (a)) where the actual road curve start position is estimated to exist based on the map data (in the range [1] in FIG. 6A) ( When the position [3] in FIG. 6A exists (only when the selection condition is satisfied), the curve start position by the radar apparatus 10 is employed as shown in FIG. In this case, as compared with the case where the curve start position based on the map data (point B in FIG. 6A) is adopted, the error from the actual curve start position (the position of the broken line in FIG. 6A). Can be reduced.

  Further, the curve start position ([[] in FIG. 6 (b)) by the radar apparatus 10 is within the range where the actual curve start position of the road is estimated from the map data (within the range [1] in FIG. 6 (b)). 4], the curve start position based on the map data (point B in FIG. 6B) is adopted as shown in FIG. 6B. In this case, compared with the case where the curve start position (position [4] in FIG. 6B) by the radar apparatus 10 is adopted, the actual road curve start position (the position of the broken line in FIG. 6A). ) Can be reduced.

[Effects of this embodiment]
In the driving support system 1 described in detail above, the radar control unit 11 of the radar apparatus 10 is obtained by receiving a reflected wave by irradiating an electromagnetic wave in the traveling direction of the host vehicle in the selection process. A curve start position (first start position) in the traveling direction of the host vehicle is estimated using relative distances to a plurality of detection points. Then, the radar control unit 11 includes node data including a large number of nodes representing positions, map data capable of expressing a road shape by link data including a large number of links connecting the nodes, the current location of the host vehicle, and the host vehicle. Based on the direction, the curve start position (second start position) in the traveling direction of the host vehicle is estimated. Then, the radar control unit 11 determines whether or not the distance between the first start position and the second start position is within an error range assumed when the radar control unit 11 estimates the second start position. .

  According to such a radar apparatus 10, since it is determined whether or not the distance between the first start position and the second start position is within an error range assumed when the second start position is estimated, Using the determination result, it is possible to specify which of the first start position and the second start position has higher detection accuracy.

  Therefore, in the present invention, it is possible to contribute to improvement of the detection accuracy of the curve start position. In addition, if the start position identified as having high detection accuracy is set as the curve start position, the detection accuracy of the curve start position can be improved.

  Further, in the radar apparatus 10, the radar control unit 11 specifies the first start position as the curve start position when it is determined that the distance between the first start position and the second start position is within the error range, When the first start position is not specified as the curve start position, the second start position is specified as the curve start position.

According to such a radar apparatus 10, the curve start position can be specified according to the determination result by the radar control unit 11.
Further, in the radar apparatus 10, the radar control unit 11 estimates the curvature of the curve (first curvature) in the traveling direction of the host vehicle based on the plurality of detection points, and uses the map data and error information relating to errors included in the map data. Based on this, a curvature range (curvature range) that is estimated to be within the curvature of the actual curve in the traveling direction of the host vehicle is calculated. Then, it is determined whether or not the first curvature is within the curvature range, it is determined that the distance between the first start position and the second start position is within the error range, and the radar control unit 11 performs the first operation. When it is determined that the curvature is within the curvature range, the first start position is specified as the curve start position.

  According to such a radar apparatus 10, whether or not the first start position is set as the curve start position is determined depending on whether or not the curvature of the curve estimated from the plurality of detection points is within the curvature range. Therefore, it is possible to prevent the curve start position from being specified using a detection point far from the curvature. Therefore, the curve start position can be specified accurately.

  Further, the radar apparatus 10 repeatedly performs the process of specifying the curve start position at a predetermined cycle, and the radar control unit 11 determines that the distance between the first start position and the second start position is within the error range. Only when the reference number of times set to a plurality of times is determined, the first start position is specified as the curve start position.

  According to such a radar apparatus 10, since the first start position is specified as the curve start position only when the distance between the first start position and the second start position is determined to be within the error range or more than the reference number of times, The influence of noise or the like can be eliminated.

  Further, in the radar apparatus 10, the radar control unit 11 sets an error range used when determining whether or not to specify the first start position as the curve start position in accordance with the interval of the nodes included in the map data. . A curvature range is also set according to the interval between nodes included in the map data.

  According to such a radar apparatus 10, it is possible to change a criterion (error range, curvature range) for determining whether or not the first start position is set as the curve start position in accordance with the estimation accuracy of the curve start position in the map data. it can.

  In the radar apparatus 10, the radar control unit 11 starts a curve within a range in which a reflected wave by irradiating an electromagnetic wave in the traveling direction of the host vehicle can be received based on the current location of the host vehicle and map data. It is determined whether or not the position exists. Then, when it is determined that the curve start position does not exist within the range in which the reflected wave can be received, at least a part of the process of specifying the curve start position is prohibited.

  According to such a radar apparatus 10, any processing is prohibited when there is no curve start position, so that the processing load can be reduced. In addition, it is possible to prevent detection points different from road shapes such as road surfaces and buildings in a gradient section or the like from being used when specifying a curve start position. In the present invention, processing may be prohibited even while traveling in a curve.

[Other Embodiments]
Embodiments of the present invention are not limited to the above-described embodiments, and can take various forms as long as they belong to the technical scope of the present invention.

  For example, in the above embodiment, the radar control unit 11 outputs the selected curve start position to an external device (the vehicle control unit 30 or the like). Information on which one of the start position, the second start position, and each start position is recommended to be selected may be output. Alternatively, the number of times that the selection condition is satisfied (counter value) may be output.

  According to such a radar apparatus 10, the curve start position can be specified in an external apparatus that has received the curve start position determination result. That is, it is possible to determine which curve start position is adopted by the application using the curve start position with reference to the determination result of the curve start position.

  In the above embodiment, when setting a range (error range) where an actual curve start position is estimated based on map data (S230), a predetermined fixed value is adopted. A value corresponding to the density of coordinate points may be adopted.

  For example, in the example shown in FIG. 6A, the actual curve start position is a point farthest from the host vehicle (point A in FIG. 6A) among a plurality of nodes arranged in a straight line. It can be estimated that it exists between the first node deviating from the straight line (point B in FIG. 6 (a)) and the node immediately before this straight point A (point C in FIG. 6 (a)). Therefore, in the process of S230, the region between the points A, B, and C may be set as a range in which the curve start position is estimated to exist. That is, a range having a different size can be set according to the interval between nodes included in the map data.

  In the above embodiment, it is determined whether the curvatures of the curves match as a selection condition. Instead of this configuration, a change in the slope of the road on which the host vehicle is traveling is detected, and the slope is When changing (especially when changing from an ascending direction to a descending direction), the curve start position by the radar apparatus 10 may not be adopted.

  In this way, when the radar apparatus 10 cannot accurately capture the curve target and the detection accuracy is expected to deteriorate, the curve start position based on the map data that is expected to be more accurate. Can be adopted.

  Furthermore, in the above embodiment, the start determination process is performed. However, the selection process may always be performed without performing the start determination process. Further, in the selection process, at least the processes of S210 to S240, S290, S330, and S340 may be performed, and other processes may be omitted.

  DESCRIPTION OF SYMBOLS 1 ... Driving assistance system, 10 ... Radar apparatus, 11 ... Radar control part, 12 ... Scanning drive part, 13 ... Optical unit, 14 ... Light emission part, 15 ... Light-receiving part, 20 ... Sensors, 30 ... Vehicle control part, 40 ... navigation device, 60 ... map data, 61 ... node, 62 ... link.

Claims (8)

A road shape detection device that is mounted on a vehicle and detects the shape of a road on which the vehicle travels,
Using the relative distances to a plurality of detection points obtained by receiving reflected waves by irradiating electromagnetic waves in the traveling direction of the host vehicle, a curve start position (hereinafter referred to as “first” in the traveling direction of the host vehicle). First starting position estimating means for estimating a starting position ”),
Based on node data including a large number of nodes representing the position, map data that can express a road shape by link data including a large number of links connecting the nodes, the current position of the own vehicle, and the direction of the own vehicle Second start position estimating means for estimating a curve start position in the traveling direction (hereinafter referred to as “second start position”);
Position determination means for determining whether the distance between the first start position and the second start position is within an error range assumed when the second start position estimation means estimates the second start position. When,
An error range setting means for setting the error range according to an interval of nodes included in the map data;
A road shape detection apparatus comprising:   In the road shape detection device according to claim 1,
  Presence determination that determines whether or not a curve start position exists within a range in which a reflected wave by irradiating an electromagnetic wave in the traveling direction of the host vehicle can be received based on the current location of the host vehicle and the map data Means,
  When it is determined by the presence determination means that the curve start position does not exist within the range in which the reflected wave can be received, the first start position estimation means, the second start position estimation means, and the position determination means Prohibit means for prohibiting processing by at least one of the means;
  A road shape detection apparatus comprising:   A road shape detection device that is mounted on a vehicle and detects the shape of a road on which the vehicle travels,
  Using the relative distances to a plurality of detection points obtained by receiving reflected waves by irradiating electromagnetic waves in the traveling direction of the host vehicle, a curve start position (hereinafter referred to as “first” in the traveling direction of the host vehicle). First starting position estimating means for estimating a starting position ”),
  Based on node data including a large number of nodes representing the position, map data that can express a road shape by link data including a large number of links connecting the nodes, the current position of the own vehicle, and the direction of the own vehicle Second start position estimating means for estimating a curve start position in the traveling direction (hereinafter referred to as “second start position”);
  Position determination means for determining whether the distance between the first start position and the second start position is within an error range assumed when the second start position estimation means estimates the second start position. When,
  Presence determination that determines whether or not a curve start position exists within a range in which a reflected wave by irradiating an electromagnetic wave in the traveling direction of the host vehicle can be received based on the current location of the host vehicle and the map data Means,
  When it is determined by the presence determination means that the curve start position does not exist within the range in which the reflected wave can be received, the first start position estimation means, the second start position estimation means, and the position determination means Prohibit means for prohibiting processing by at least one of the means;
  A road shape detection apparatus comprising: In the road shape detection device according to any one of claims 1 to 3 ,
Specifying means for specifying the first start position as a curve start position when the position determination means determines that the distance between the first start position and the second start position is within the error range;
A road shape detection apparatus comprising: In the road shape detection device according to claim 4 ,
The road shape detection device, wherein the specifying unit specifies the second start position as the curve start position when the first start position is not specified as the curve start position. In the road shape detection device according to claim 4 or 5 ,
Curvature estimation means for estimating a curvature of a curve in the traveling direction of the host vehicle (hereinafter referred to as “first curvature”) based on the plurality of detection points;
Based on the map data and error information regarding errors included in the map data, a curvature range (hereinafter referred to as “curvature range”) that is estimated to be within the curvature of the actual curve in the traveling direction of the host vehicle is calculated. A curvature range calculating means to perform,
Curvature determining means for determining whether the first curvature is within the curvature range;
With
The specifying means determines that the distance between the first start position and the second start position is within the error range by the position determination means, and the first curvature is within the curvature range by the curvature determination means. When it is determined that the road shape is within the range, the first start position is specified as the curve start position. In the road shape detection device according to any one of claims 4 to 6 ,
Each means constituting the road shape detection device repeatedly performs a process to be performed by itself at a predetermined cycle,
The specifying unit is configured to perform the first determination only when the position determination unit determines that the distance between the first start position and the second start position is within the error range. A road shape detection device characterized by specifying a start position as a curve start position. In the road shape detection device according to any one of claims 1 to 7,
Output means for outputting at least the determination result by the position determination means;
A road shape detection apparatus comprising: