JP7699414B2 - OBJECT IDENTIFICATION DEVICE, MOBILE BODY, AND OBJECT IDENTIFICATION METHOD - Google Patents

Description

This disclosure relates to an object identification device, a moving body, and an object identification method.

Conventionally, object identification devices are known that can detect objects based on the reciprocation of detection waves between a moving body such as a vehicle and the object. For example, Patent Document 1 discloses a configuration that corrects the reflection intensity of the detection wave according to the height of the object and the distance from the vehicle to the object, and can identify the type of object based on the corrected reflection intensity.

JP 2012-247215 A

However, since object identification devices detect objects based on the round-trip detection waves, they can also detect objects that are located outside the travel path, such as to the side of a moving body. Depending on the type of object, there is a possibility that such objects may collide with the moving body, so the object identification device may also treat the object as a control target.

However, when the above objects are set as control targets, small objects smaller than a certain value, such as poles that are unlikely to collide with a moving object, may also be identified. Such identification may cause other devices that operate based on the identification to malfunction, which may be annoying to users.

The objective of the present disclosure is to provide an object identification device, a moving body, and an object identification method that are capable of accurately identifying objects.

The object identification device according to the present disclosure comprises:
an area determination circuit that determines whether an object detected based on a detection wave transmitted and received by a sensor mounted on the moving body is located within a predetermined area in front of the moving body;
an identification circuit which, when it is determined by the area determination circuit that the object is located within the predetermined area, identifies whether or not the object is a controlled object based on a difference between a first coordinate of a first reflection point on the object of a detection wave received by the moving body at a first position at a first time and a second coordinate of a second reflection point on the object of a detection wave received by the moving body at a second position at a second time after the first time, and identifies the object as a non-controlled object when the difference between the first coordinate and the second coordinate is equal to or less than a predetermined value ;
Equipped with.

A moving body according to the present disclosure includes:
The above object identification device;
an object detection unit having a sensor that transmits and receives the detection wave and detects the object based on the detection wave;
Equipped with.

The object identification method according to the present disclosure includes:
1. A method for identifying an object, comprising:
determining whether or not an object detected based on a detection wave transmitted and received by a sensor mounted on the moving body is located within a predetermined area in front of the moving body;
If it is determined that the object is located within the predetermined area,
identifying whether or not the object is a controlled object based on a difference between a first coordinate of a first reflection point on the object of a detection wave received by the moving body at a first position at a first time and a second coordinate of a second reflection point on the object of a detection wave received by the moving body at a second position at a second time after the first time ;
If the difference between the first coordinates and the second coordinates is equal to or smaller than a predetermined value, the object is identified as an uncontrolled object .

This disclosure allows for accurate identification of objects.

1 is a block diagram showing an example configuration of a vehicle to which a vehicle control unit according to an embodiment of the present disclosure is applied. FIG. 2 is a diagram illustrating an example of an arrangement of an object detection unit in a vehicle. FIG. 10 is a diagram for explaining a general method for setting a discrimination threshold for reflection intensity. 11 is a diagram for explaining the relationship between an object below and a detection wave. FIG. FIG. 13 is a diagram showing an example of change in reflection intensity relative to distance from an object below. 11 is a diagram showing an example of a path of a detection wave when an object is a columnar object; FIG. FIG. 13 is a diagram illustrating an example of a relationship between a shape determination threshold and a distance. 11 is a diagram showing an example of the relationship between the reflection intensity of a columnar object and a discrimination threshold; FIG. FIG. 13 is a diagram showing an example of detection of an object located within a predetermined area. FIG. 13 is a diagram showing an example of detection of an object located within a predetermined area. FIG. 13 is a diagram showing the relationship between the distance to an object in the Y direction and the difference in coordinates of the object. FIG. 13 is a diagram showing an example of detection of an object located within a predetermined area. FIG. 13 is a diagram showing an example of detection of an object located within a predetermined area. 5 is a flowchart showing an example of an operation of identification control in a vehicle control unit. 5 is a flowchart showing an example of an operation of identification control in a vehicle control unit. FIG. 2 is a diagram illustrating an example of an arrangement of an object detection unit in a vehicle.

(Embodiment)
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. Fig. 1 is a block diagram showing an example of the configuration of a vehicle 1 to which a vehicle control unit 100 according to an embodiment of the present disclosure is applied.

As shown in FIG. 1, the vehicle 1 is a moving body that has a function of identifying whether or not an object existing around the traveling path is likely to collide with the vehicle 1. The vehicle 1 has an acceleration unit 10, a braking unit 20, a vehicle speed information acquisition unit 30, an object detection unit 40, and a vehicle control unit 100.

The acceleration unit 10 is an acceleration device that accelerates or decelerates the vehicle 1 in response to an acceleration request from the vehicle control unit 100.

The braking unit 20 is a braking device that applies the brakes to the vehicle 1 in response to a braking request from the vehicle control unit 100.

The vehicle speed information acquisition unit 30 acquires information related to the speed of the vehicle 1. Specifically, the vehicle speed information acquisition unit 30 acquires information on the vehicle speed and acceleration of the vehicle 1 from the acceleration unit 10, etc., and acquires brake information, etc. from the braking unit 20, etc. The vehicle speed information acquisition unit 30 also acquires information such as steering angle from an operating unit such as a steering wheel (not shown).

The object detection unit 40 is an on-board sensor such as sonar or radar, and detects objects present in the vicinity of the travel path of the vehicle 1 by transmitting detection waves such as ultrasonic waves or millimeter waves (electromagnetic waves) and receiving the detection waves reflected by the objects and returning. The object detection unit 40 is provided at the front end or rear end of the vehicle 1.

Figure 2 is a diagram showing an example of the arrangement of the object detection unit 40 in the vehicle 1. In the following description, a Cartesian coordinate system (X, Y, Z) is used. The same Cartesian coordinate system (X, Y, Z) is used in the drawings described below. For example, the X direction indicates the left-right direction of the vehicle 1, the Y direction indicates the front-rear direction (travel direction) of the vehicle 1, and the Z direction indicates the up-down direction (height direction) of the vehicle 1.

For example, as shown in FIG. 2, the object detection unit 40 has a total of four wave transmission/reception sensors 41, one at each end in the X direction at the end on the positive side in the Y direction of the vehicle 1, and two at the center in the X direction.

The wave transmission/reception sensor 41 is a sensor capable of transmitting and receiving detection waves. For example, in the case of a sonar, the wave transmission/reception sensor 41 applies a voltage of a predetermined frequency to a piezoelectric element, thereby generating and transmitting ultrasonic waves (detection waves) of the same frequency.

The wave transmission/reception sensor 41 receives the detection wave that is transmitted from one of the four wave transmission/reception sensors 41 and then reflected off the object 2. In the case of a sonar, for example, the wave transmission/reception sensor 41 converts the sound pressure of the detection wave into a voltage using a piezoelectric element, and rectifies the converted voltage to convert the received detection wave into a sound wave reception intensity (reflection intensity).

The distance between the vehicle 1 and the object 2 can be calculated by measuring the flight time of the detection wave from one of the four wave transmission/reception sensors 41 to one of the four wave transmission/reception sensors 41, via the object 2, and then round trip. In addition, by calculating the distance between the vehicle 1 and the object 2, it is possible to calculate the coordinates of the position where the detection wave is reflected by the object 2 based on the principle of triangulation.

In addition, since a total of four wave transmission/reception sensors 41 are provided, the detection wave transmitted from each of the wave transmission/reception sensors 41 can be received by each of the four wave transmission/reception sensors 41. Therefore, when a detection wave transmitted from at least one wave transmission/reception sensor 41 is received by two wave transmission/reception sensors 41, each of the detection waves received by the two wave transmission/reception sensors 41 returns to each wave transmission/reception sensor 41 via different paths D1 and D2.

In paths D1 and D2, the detection wave is reflected at different positions P1 and P2 on the object 2. Therefore, if the detection wave is received by two wave transmission/reception sensors 41, it is possible to calculate two coordinates at positions P1 and P2 of the object 2. Note that the object 2 in FIG. 2 is a wall having a plane parallel to the X direction.

Returning to FIG. 1, the vehicle control unit 100 is, for example, an ECU (Electronic Control Unit) or the like, and includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an input/output circuit (not shown). Based on a preset program, the vehicle control unit 100 identifies whether or not an object existing in the vicinity of the travel path is a control target (e.g., an object with a possibility of collision), and performs a predetermined driving control.

The vehicle control unit 100 has an identification unit 110, a shape determination unit 120, a modification unit 130, an area determination unit 140, and a control unit 150. The identification unit 110 and the area determination unit 140 correspond to the "object identification device" of the present disclosure. The identification unit 110 corresponds to the "identification circuit" of the present disclosure, and the area determination unit 140 corresponds to the "area determination circuit" of the present disclosure.

When an object 2 is located in the area ahead of the vehicle 1, and a detection wave transmitted from the vehicle 1 towards the object is reflected by the object and received by the vehicle 1, the identification unit 110 identifies whether the object is a controlled object or not based on the comparison result between the reflection intensity of the detection wave and an identification threshold. The forward area is, for example, the area on the + side of the vehicle 1 in the Y direction, that is, the area on the vehicle 1 side of a first control object determination line L1 described later.

Specifically, when the reflection intensity based on the detection wave received by any of the wave transmitting/receiving sensors 41 is equal to or greater than the discrimination threshold, the discrimination unit 110 discriminates that the object is a controlled object, and when the reflection intensity is less than the discrimination threshold, the discrimination unit 110 discriminates that the object is a non-controlled object, i.e., not a controlled object.

The discrimination threshold is a threshold that is compared with the reflection intensity based on the detection wave received by the wave transmission/reception sensor 41 to serve as a discrimination criterion for determining whether an object is a control target of the vehicle 1. When the reflection intensity of the object 2 located in the forward area is equal to or greater than the discrimination threshold, the discrimination unit 110 discriminates that the object 2 is a control target.

In addition, because the detection wave attenuates rapidly in the air, the amount of attenuation increases as the distance between the vehicle 1 and the object increases. Therefore, as shown in FIG. 3, for example, the reflection intensity based on the detection wave received by the wave transmission/reception sensor 41 also decreases as the distance between the vehicle 1 and the object increases. Therefore, the discrimination threshold is generally set to be lower as the distance between the vehicle 1 and the object increases, in accordance with the reflection intensity.

However, for objects below, such as curbs, the reflection intensity does not change in the same way as in Figure 3 due to the relationship between the angle of incidence and the angle of reflection of the detection wave, for example. For example, as shown in Figure 4, if there is an object below 2A that is closer to the vehicle 1 than the object below 2B, the object below 2A is in a position where it is difficult for the detection wave transmitted from the wave transmitting/receiving sensor 41 to hit it, and so the reflection intensity is small for the object below 2A that is located close by.

In contrast, the detection wave is more likely to hit the object below 2B, which is located at a relatively large distance from the vehicle 1, and the detection wave reflected by the object below 2B is also more likely to enter the wave transmission/reception sensor 41, resulting in a large reflection intensity. Specifically, as shown in FIG. 5, the reflection intensity tends to change with distance such that the reflection intensity gradually increases as the distance increases from a position at distance T1, and after the reflection intensity reaches a maximum value at distance T2, the reflection intensity begins to decrease.

Therefore, if a discrimination threshold is set that decreases with distance, as shown in Figure 3, the reflection intensity of the object below will exceed the discrimination threshold. The object below is located on the road surface and has a height that allows collision with the main body of the vehicle 1 to be avoided, and therefore is not an obstacle (a non-controlled object). Such an object below may be identified as a controlled object due to the emphasis on the reflection intensity. Note that Figure 4 shows an example of an object (object below) located at the rear of the vehicle 1, but the same applies to an object located in front of the vehicle 1.

Therefore, in this embodiment, as shown by the dashed line in Figure 5, the discrimination threshold is set so that the reflection intensity from the object below does not exceed the discrimination threshold. Specifically, the discrimination threshold is set to increase stepwise from a position at a distance T1 away from the vehicle 1 to a distance T2 at which the reflection intensity reaches a maximum value, and then to decrease as the distance from the vehicle 1 increases.

This makes it possible to prevent objects below, such as curbs, from being identified as objects to be controlled (obstacles).

The shape determination unit 120 determines the shape of the object based on two coordinates of the object calculated by detecting the detection waves that have propagated through different paths. Specifically, the shape determination unit 120 determines whether the object is a columnar object based on the two coordinates. A columnar object is, for example, a cylindrical object such as a pole installed at the edge of a road.

Specifically, the shape determination unit 120 calculates coordinates indicating the position where the detection wave is reflected on the object based on the principle of triangulation from the distance between the vehicle 1 and the object, which is calculated based on the round trip of the detection wave.

The shape determination unit 120 calculates two coordinates based on the detection waves received by at least two wave transmission/reception sensors 41. The shape determination unit 120 then determines whether or not the object is a columnar object based on the coordinate difference between the two coordinates. Specifically, if the coordinate difference is equal to or greater than the shape determination threshold, the shape determination unit 120 determines that the object is not a columnar object, and if the coordinate difference is less than the shape determination threshold, the shape determination unit 120 determines that the object is a columnar object.

The shape determination threshold is a threshold that corresponds to a value where the difference between two coordinates is close, such as for a columnar object that is thinner than a pedestrian or vehicle, and is set appropriately depending on the thickness of the columnar object, etc.

As shown in FIG. 6, the columnar object 2C has a circumferential surface, and therefore reflects detection waves from two different points P3 and P4 that are close to each other in coordinate positions toward the two wave transmitting and receiving sensors 41 along different paths D3 and D4.

In contrast, a non-columnar object other than the columnar object 2C (for example, an object 2 such as a wall having a plane extending in the X direction shown in FIG. 2) reflects detection waves from two different points P1 and P2 whose coordinate positions are spaced apart, along different paths D1 and D2, toward each of the two wave transmitting and receiving sensors 41.

In this way, since there is a clear difference in the coordinate difference between a columnar object and a non-columnar object, it is possible to determine whether or not an object is a columnar object based on the shape determination threshold. Furthermore, while the reflection intensity is susceptible to fluctuations in value due to disturbances (wind, rain, heat, etc.), the coordinate difference is less susceptible to disturbances, so it is possible to accurately determine whether or not an object is a columnar object.

The coordinate difference is expressed by the distance in at least the X direction component of the X direction and Y direction components of the two coordinates. Note that the coordinate difference may take into account the distance in the Y direction component in addition to the X direction component.

In addition, since the calculated coordinate difference may differ depending on the distance between the vehicle 1 and the object, in this case, for example, as shown in FIG. 7, a different shape determination threshold may be set for each distance between the vehicle 1 and the object. In the example shown in FIG. 7, the shape determination threshold is set to be larger as the distance between the vehicle 1 and the object becomes longer.

When the detection wave is reflected by two points on the object and received by the vehicle 1, the modification unit 130 modifies the discrimination sensitivity of the discrimination unit 110, which discriminates whether or not the object is a controlled object, depending on the positions of the two points. Specifically, the modification unit 130 modifies the discrimination threshold depending on the coordinate difference between the two coordinates. For example, the modification unit 130 modifies the discrimination sensitivity by changing the discrimination threshold depending on whether or not the object is a columnar object based on the determination result of the shape determination unit 120.

In this embodiment, as shown in FIG. 8, the discrimination threshold for non-columnar objects is set to a first threshold corresponding to an underlying object such as a curbstone. The first threshold is the discrimination threshold shown in FIG. 5 above. For example, when the coordinate difference between two coordinates (the distance between two points) is equal to or greater than the shape determination threshold, the discrimination threshold is set to match the reflection intensity of the detection wave for the non-controlled object.

Since the columnar object is erected on the road surface and has a certain height, the reflection strength does not increase with distance, as occurs with objects below. Therefore, the reflection strength based on the detection wave from the columnar object decreases as the distance between the vehicle 1 and the columnar object increases.

When the distance between the vehicle 1 and the columnar object increases to a certain extent, the reflection intensity of the columnar object falls below the first threshold, and the identification unit 110 identifies the columnar object as a non-controlled object, not a controlled object.

Therefore, when the object is a columnar object, the change unit 130 changes the discrimination threshold to a second threshold corresponding to the reflection intensity of the columnar object. The second threshold, like the reflection intensity of the columnar object, changes so that it becomes smaller as the distance between the vehicle 1 and the columnar object increases.

By doing this, the identification unit 110 can reliably identify the columnar object as the object to be controlled.

The change unit 130 may also determine whether or not to perform control to change the discrimination threshold depending on the distance between the vehicle 1 and the object. The greater the distance between the vehicle 1 and the object, the greater the error in the calculated coordinates of the object, which is likely to affect the accuracy of determining the columnar object.

Therefore, when the distance between the vehicle 1 and the object is equal to or less than a predetermined distance, the change unit 130 performs control to change the above-mentioned discrimination threshold. The predetermined distance is, for example, a distance at which a certain degree of accuracy in calculating the coordinates of the object is ensured, and is set appropriately according to the reflection intensity based on the detection wave of the object detection unit 40, etc.

By doing this, it is possible to identify columnar objects as objects to be controlled within a range where the accuracy of identifying columnar objects is ensured.

The area determination unit 140 determines whether the object 2 detected based on the detection wave that can be transmitted and received from the vehicle 1 is located within a predetermined area in front of the vehicle 1. As shown in FIG. 9, the predetermined area is an area on the side of the vehicle 1 and is an area between the first control object determination line L1 and the second control object determination line L2.

The first control object determination line L1 is a line that passes through a position that is a predetermined width away from the side of the vehicle 1. The predetermined width is, for example, the distance in the X direction between the edge of the road and the side of the vehicle 1 when the vehicle 1 is traveling in the center of the road, and can be set appropriately taking safety, etc. into consideration.

The second control object determination line L2 is a line that passes through a position farther away from the vehicle 1 than the first control object determination line L1. For example, when an object 2 is located between the first control object determination line L1 and the second control object determination line L2, the second control object determination line L2 is a line that passes through a position where there is a high possibility of a collision between the object 2 and the vehicle 1 when the vehicle 1 moves in the traveling direction (Y direction) and approaches the object 2, and can be set appropriately taking safety, etc. into consideration.

Note that the first control object determination line L1 and the second control object determination line L2 are shown on the negative side of the X direction of the vehicle 1 in FIG. 9 and other figures, but they may also be set on the positive side of the X direction of the vehicle 1.

The area determination unit 140 compares the discrimination threshold set by the modification unit 130 with the reflection intensity based on the detected object 2, and if the reflection intensity is equal to or greater than the discrimination threshold, determines whether or not the object 2 is located within a specified area based on the coordinates indicating the position of the object 2.

When the area determination unit 140 determines that the coordinates of the object 2 are outside the specified area, for example, closer to the vehicle 1 side (the above-mentioned forward area) than the range between the first control object determination line L1 and the second control object determination line L2, the identification unit 110 identifies the object as a control object.

If the area determination unit 140 determines that the coordinates of the object 2 are outside the specified area and are located in an area on the opposite side of the second control object determination line L2 from the vehicle 1, the identification unit 110 identifies the object as a non-controlled object.

In addition, if the area determination unit 140 determines that the coordinates of the object are located within a predetermined area, the identification unit 110 determines whether the object is a controlled object or not, depending on the curvature of the reflecting surface of the object 2 estimated based on the detection wave.

Specifically, when the area determination unit 140 determines that the coordinates of the object 2 are located within a predetermined area, the identification unit 110 determines whether or not the object is a controlled object based on the time-series change in the coordinates of the object 2. More specifically, the identification unit 110 determines whether or not the object is a controlled object based on the difference between the first coordinates and the second coordinates.

The first coordinates are coordinates indicating a first reflection point on object 2 of the detection wave received by vehicle 1 at a first position. The second coordinates are coordinates indicating a second reflection point on object 2 of the detection wave received by vehicle 1 at a second position.

The difference between the first coordinate and the second coordinate, for example, the difference between the two coordinates, may be expressed, for example, as a distance on the XY plane.

The first position is the position of the vehicle 1 when the detection wave is received by the wave transmission/reception sensor 41b, for example, at time t1. The second position is the position of the vehicle 1 when the detection wave is received by the wave transmission/reception sensor 41a, for example, at time t2, which is later than time t1.

In the following description, the position of the vehicle 1 shown in FIG. 9 is referred to as the first position, and the position of the vehicle 1 shown in FIG. 10 is referred to as the second position. In FIG. 9 and FIG. 10, the second position is located on the + side in the Y direction from the first position.

The detection wave transmitted from the wave transmission/reception sensor 41 (41a, 41b) differs between the first position and the second position, and therefore the path of the detection wave traveling back and forth between the vehicle 1 and the object 2 differs. For example, in FIG. 9, the detection wave transmitted from the wave transmission/reception sensor 41b, which is the second from the negative side in the X direction, is received by the wave transmission/reception sensor 41a, which is located at the end of the negative side in the X direction, via the first reflection point P5. Also, in FIG. 10, the detection wave transmitted from the wave transmission/reception sensor 41a, which is located at the end of the negative side in the X direction, is received by the wave transmission/reception sensor 41b, which is the second from the negative side in the X direction, via the second reflection point P6. Note that in FIG. 9 and other figures, the third wave transmission/reception sensor from the negative side in the X direction is indicated by the symbol 41c, and the wave transmission/reception sensor located at the end of the positive side in the X direction is indicated by the symbol 41d.

Due to the relationship between the angle of incidence and the angle of reflection of the detection wave, a difference occurs between the first coordinate associated with the first reflection point P5 and the second coordinate associated with the second reflection point P6.

Figure 11 shows the results of acquiring the coordinates of a cylindrical object placed on the side of the road on which vehicle 1 is traveling while vehicle 1 is moving, and calculating the difference between these two coordinates for each distance traveled by vehicle 1.

The vertical axis in FIG. 11 indicates the difference between two coordinates, and the horizontal axis indicates the distance in the Y direction. The difference between the two coordinates is the difference between the coordinates detected first and the coordinates detected at the positions corresponding to each distance. The distance in the Y direction is the distance from the position where the coordinates were detected first to the end of the vehicle. Note that, although an example has been shown in which the vehicle 1 uses different wave transmission/reception sensors 41 for transmitting waves at the first position in FIG. 9 and the second position in FIG. 10, waves may be transmitted from the same wave transmission/reception sensor 41.

In FIG. 11, the symbol L3 indicates the change in the difference in coordinates of a cylindrical object with a diameter larger than L4 and L5, and the symbol L4 indicates the change in the difference in coordinates of a cylindrical object with a diameter smaller than L3 and L5. Furthermore, the symbol L5 indicates the change in the difference in coordinates of a cylindrical object with a diameter between the diameters of L3 and L4.

As shown in FIG. 11, the smaller the diameter of the cylindrical object, the smaller the difference between the first coordinate and the second coordinate.

This indicates that the greater the curvature of the reflective surface of object 2 (the smaller the diameter), the smaller the change in coordinates over time. Therefore, the identification unit 110 compares the difference between the first coordinate and the second coordinate with a predetermined value, and determines whether or not object 2 is a controlled object based on the comparison result.

The predetermined value is, for example, a value that corresponds to the difference between the first coordinate and the second coordinate when the object is a columnar object (pole), and is a value that is set appropriately depending on the curvature of the type of object to be controlled.

For example, when the difference between the first coordinate and the second coordinate is greater than a predetermined value, the identification unit 110 identifies the object 2 as a large columnar object, with the curvature of the reflective surface of the object 2 being smaller than a predetermined value. In this case, the identification unit 110 identifies the object 2 as an object to be controlled. Note that large columnar objects include, for example, utility poles, but may also be objects that partially have a reflective surface with a small curvature.

For example, as shown in FIG. 12, when the object 2 is larger than those in FIG. 9 and FIG. 10, the vehicle 1 receives the detection wave through the first reflection point P7 and the second reflection point P8, which have a larger coordinate difference than the first reflection point P5 in FIG. 9 and the second reflection point P6 in FIG. 10. Specifically, the vehicle 1 transmits a detection wave from the wave transmission/reception sensor 41a at the first position (position of the two-dot chain line), and the detection wave is received by the wave transmission/reception sensor 41b through the first reflection point P7. The vehicle 1 also transmits a detection wave from the wave transmission/reception sensor 41b at the second position (position of the solid line), and the detection wave is received by the wave transmission/reception sensor 41a through the second reflection point P8, which has a coordinate difference of a predetermined value or more from the first reflection point P7. Note that FIG. 12 shows an example in which the vehicle 1 transmits from different wave transmission/reception sensors 41 at the first and second positions, but the same wave transmission/reception sensor may transmit the detection wave.

When a large object is located within a specified area, the object is considered as a control target, taking into consideration the possibility of collision with the vehicle 1. In this embodiment, as described above, the difference in the coordinates of the reflection point between the first position and the second position can be clearly determined, so that such an object can be accurately identified as a control target.

If the difference between the first coordinate and the second coordinate is equal to or less than a predetermined value, the identification unit 110 identifies the object 2 as an object with a large curvature of the reflective surface and a small diameter. In this case, the identification unit 110 identifies the object 2 as an uncontrolled object.

The specified area is close to the vehicle 1, but since the vehicle 1 does not protrude forward much, small objects such as poles that are unlikely to collide with the vehicle 1 even if it approaches may exist within the specified area. If such small objects are also treated as objects to be controlled, it may lead to the operation of other devices, such as braking devices, in response to the small objects. Furthermore, the malfunction of such other devices is annoying to the user.

In this embodiment, if the small object has a large curvature of the reflecting surface and is unlikely to collide with the object, the identification unit 110 identifies the small object as a non-controlled object. For example, as shown in Figures 9 and 10, if the object 2 is small, the difference in coordinates between the first reflection point P5 and the second reflection point P6 becomes small.

As a result, it is possible to identify that the object 2 is a small object based on the difference in coordinates between the first reflection point P5 and the second reflection point P6. In this embodiment, the identification unit 110 can identify the object 2 as an uncontrolled object, which can prevent other devices from malfunctioning.

In addition, after the area determination unit 140 has determined that the object is located within a predetermined area, the identification unit 110 may determine whether or not the object 2 is a controlled object based on time-series changes in the coordinates of the object at three or more times.

For example, when the determination is based on a time series change between two times, such as the difference between the coordinates at time t1 and the coordinates at time t2, as shown in Figures 9 and 10, the two coordinates may be close to each other depending on the moving speed of the vehicle 1 and the transmission and reception conditions of the detection waves of each transmission and reception sensor 41.

Therefore, in addition to the difference in coordinates at times t1 and t2, as shown in FIG. 13, the coordinates of reflection point P9 are obtained at the position at time t3 (t3>t2) and the difference in coordinates at times t2 and t3 is calculated. Then, when it is determined that both of the differences between the two sets of coordinates are equal to or less than a predetermined value (determined to be an uncontrolled object), the identification unit 110 identifies the object as an uncontrolled object.

In this way, by using the difference information between two sets of coordinates for identification control, the identification accuracy of the object identification device can be improved.

Note that, although information on the difference between two sets of coordinates is used here, information on the difference between three or more sets of coordinates may be used. Then, when the number of times that the coordinate difference among the three or more sets of coordinates is determined to be equal to or less than a predetermined value (the number of times that the object is determined to be a non-controlled object) is equal to or greater than a predetermined number, the identification unit 110 identifies the object as a non-controlled object.

The specified number of times can be set arbitrarily, such as at least two times.

By doing this, the recognition accuracy of the recognition unit 110 can be further improved.

The control unit 150 predicts the possibility of a collision between the vehicle 1 and the controlled object based on the movement of the controlled object identified by the identification unit 110 and the relative speed of the controlled object based on the movement of the vehicle 1 (vehicle speed information). The method of predicting the possibility of a collision can be, for example, a known technique.

Then, the control unit 150 outputs an acceleration request to the acceleration unit 10 or a braking request to the braking unit 20 depending on the possibility of a collision and the acceleration state of the vehicle 1.

This allows for appropriate driving control, such as controlling the braking operation for accurately identified control objects.

An example of the operation of the identification control in the vehicle control unit 100 configured as described above will be described. Figures 14 and 15 are flowcharts showing an example of the operation of the identification control in the vehicle control unit 100. The processing in Figures 14 and 15 is executed as appropriate, for example, while the vehicle 1 is traveling. This flowchart also assumes that a detection wave has been transmitted from the wave transmission/reception sensor 41.

As shown in FIG. 14, the vehicle control unit 100 determines whether or not the two wave transmission/reception sensors 41 have received a detection wave (step S101). If the result of the determination is that the two wave transmission/reception sensors 41 have not received a detection wave (step S101, NO), the process of step S101 is repeated.

On the other hand, if the detection wave is received by both wave transmission/reception sensors 41 (step S101, YES), the vehicle control unit 100 acquires information on the distance between the vehicle 1 and the object and the reflection intensity of the detection wave (step S102).

Next, the vehicle control unit 100 determines whether the distance between the vehicle 1 and the object is within a predetermined distance (step S103). If the result of the determination is that the distance is greater than the predetermined distance (step S103, NO), the process proceeds to step S105.

On the other hand, if the distance is within the predetermined distance (step S103, YES), the vehicle control unit 100 determines whether the coordinate difference between the two coordinates is less than the shape determination threshold (step S104).

If the coordinate difference is equal to or greater than the shape determination threshold (step S104, NO), the vehicle control unit 100 sets the discrimination threshold to a first threshold for non-columnar objects (step S105). On the other hand, if the coordinate difference is less than the shape determination threshold (step S104, YES), the vehicle control unit 100 sets the discrimination threshold to a second threshold for columnar objects (step S106).

As shown in FIG. 15, after step S105 or step S106, the vehicle control unit 100 determines whether the reflection intensity is equal to or greater than the discrimination threshold (step S107). If the result of the determination is that the reflection intensity is less than the discrimination threshold (step S107, NO), the process proceeds to step S111.

On the other hand, if the reflection intensity is greater than or equal to the discrimination threshold (step S107, YES), the vehicle control unit 100 determines whether the coordinates are within a predetermined area (step S108).

If the result of the determination is that the coordinates are not within the predetermined area (step S108, NO), the process transitions to step S112. Note that in step S108, if the coordinates are not within the predetermined area, this means that the coordinates are located in the area ahead of the vehicle 1. The determination process for distinguishing between the area on the opposite side of the vehicle 1 and the area ahead of the second control object determination line L2 may be additionally performed before or after step S108.

On the other hand, if the coordinates are within the predetermined area (step S108, YES), the vehicle control unit 100 determines whether the difference between the two coordinates obtained at different positions is greater than a predetermined value (step S109).

If the result of the determination is that the difference is equal to or less than the predetermined value (step S109, NO), the vehicle control unit 100 determines whether the number of times that the difference is equal to or less than the predetermined value is less than a predetermined number (step S110). If the result of the determination is that the number is less than the predetermined number (step S110, YES), the process proceeds to step S112. Here, the predetermined number is a preset number equal to or greater than 2.

On the other hand, if the number of times is equal to or greater than the predetermined number (step S110, NO), the vehicle control unit 100 identifies the object as a non-controlled object (step S111).

Returning to the judgment of step S109, if the difference is greater than the predetermined value (step S109, YES), the vehicle control unit 100 identifies the object as a control target (step S112). After step S111 or step S112, this control ends.

After step S112, the vehicle control unit 100 performs a predetermined driving control on the vehicle 1.

According to the present embodiment configured as described above, whether or not the object 2 is a control target is determined according to the curvature of the reflecting surface of the object 2. Specifically, whether or not the object 2 is a control target is determined based on the time series change in the coordinates of the object 2, for example, the difference between the first coordinates associated with the first position and the second coordinates associated with the second position.

This makes it possible to identify the size of the object 2. As a result, it is possible to accurately identify whether the object 2 is a controlled object or not.

In addition, if the difference between the two coordinates is equal to or less than a predetermined value, the object 2 can be determined to be a small object such as a pole, and therefore objects that are unlikely to collide with the vehicle 1 can be identified as non-controlled objects. Note that in this embodiment, objects can be accurately identified.

In addition, since object 2 is identified based on three or more time series changes in the coordinates of object 2, the accuracy of identifying object 2 can be improved compared to a configuration in which object 2 is identified based on two time series changes.

In addition, if the number of times that object 2 is determined to be an uncontrolled object is equal to or greater than a predetermined number of times, object 2 is identified as an uncontrolled object, thereby further improving the accuracy of identifying object 2.

In addition, since the specified area is a lateral area that is a specified width away from the side of the vehicle 1, the object to be identified according to the curvature of the reflective surface can be specified as an object in the lateral area of the vehicle 1. As a result, it is possible to identify whether an object on the side of the vehicle 1 is a control object, in addition to an object located in the forward area, making it easier to accurately identify the object 2.

In addition, the discrimination threshold is changed depending on whether the object is a columnar object or not, so columnar objects can be accurately identified as objects to be controlled.

In addition, since the discrimination threshold (first threshold) is set to match the reflection intensity of the non-controlled object, when the object is a non-controlled object, it is possible to reliably prevent the object from being discriminated as a controlled object.

In addition, in this embodiment, it is possible to suppress erroneous identification of an object due to the fact that the change trend of the reflection intensity is not the same depending on the shape of the object. As a result, in this embodiment, it is possible to stably identify the object.

In addition, because the system determines whether an object is a columnar object based on the coordinate difference between the two coordinates, it is possible to prevent erroneous determination of the object's shape due to the influence of disturbances. As a result, in this embodiment, the object's shape can be accurately determined.

In addition, since the system determines whether or not to change the discrimination sensitivity depending on the distance between the vehicle 1 and the object, the system can identify the columnar object as a controlled object within a range where the discrimination accuracy of the columnar object is ensured. As a result, the system can accurately determine that the object is a columnar object.

In the above embodiment, whether or not the object 2 is a controlled object is identified based on the time series changes in the coordinates of the object 2, but the present disclosure is not limited to this. For example, whether or not the object 2 is a controlled object may be identified by acquiring information on the degree of curvature of the reflective surface of the object 2 from an external device.

In addition, in the above embodiment, if the number of times that the object 2 is determined to be an uncontrolled object is equal to or greater than a predetermined number of times, the object 2 is identified as an uncontrolled object, but the present disclosure is not limited to this. For example, if the object 2 is determined to be a controlled object even once, the object 2 may be identified as a controlled object.

In addition, in the above embodiment, the identification unit 110 identifies whether or not the object 2 is a controlled object based on the time series changes in the coordinates of the object 2 at two times, but the present disclosure is not limited to this, and as shown in FIG. 6, it may also identify whether or not the object 2 is a controlled object based on the difference between two coordinates of the reflecting surface of the object 2 detected by different detection wave paths at one time.

If the difference between the two coordinates of the reflective surface of object 2 detected at one time is greater than a predetermined value, the identification unit 110 may determine that object 2 is a large columnar object with a small curvature of the reflective surface, and identify object 2 as an object to be controlled.

On the other hand, if the difference between the two coordinates of the reflective surface of object 2 detected at one time is equal to or less than a predetermined value, the identification unit 110 determines that the reflective surface of object 2 has a large curvature and a small diameter, and identifies object 2 as an uncontrolled object.

In addition, in the above embodiment, when the object 2 in the predetermined area is determined to be a small object with a large curvature, the identification unit 110 identifies the object 2 as a non-control object, but the present disclosure is not limited to this. For example, the area determination unit 140 may shift the second control object determination line L2 toward the vehicle 1 to narrow the predetermined area.

By doing this, the object 2 is removed from the specified area, and after narrowing the specified area, the object 2 can be removed from the objects to be identified by the identification unit 110.

In addition, while the above embodiment includes a shape determination unit 120 and a modification unit 130, the present disclosure is not limited to this, and the shape determination unit 120 and modification unit 130 may not be included.

In addition, in the above embodiment, the discrimination sensitivity is set to the discrimination threshold and the discrimination threshold is changed, but the present disclosure is not limited to this. For example, the discrimination sensitivity may be set to the reflection intensity and the reflection intensity may be changed instead of changing the discrimination threshold. When the discrimination sensitivity is set to the reflection intensity, the reflection intensity is changed by changing the output pressure (sound pressure, etc.) of the detection wave or the amplification degree of the detection wave.

Specifically, when the object is a columnar object, the modification unit 130 modifies the reflection intensity by increasing the output pressure of the detection wave or the amplification degree of the detection wave so that the reflection intensity exceeds the discrimination threshold (first threshold).

In this way, objects can be identified reliably.

In addition, in the above embodiment, a cylindrical object such as a pole is exemplified as a columnar object, but the present disclosure is not limited to this, and any columnar object may be used as long as the object has a shape that allows the detection wave transmitted from the wave transmitting/receiving sensor 41 to be reflected toward the two wave transmitting/receiving sensors 41 at two points on the object (for example, a columnar object with multiple reflecting portions such as an H-shaped steel beam).

An object that is to be determined as being a control target may also include a vehicle. For example, the corners of a vehicle body have a curved surface, but the curvature of this curved surface is smaller than the curvature of the curved surface of a small pole.

Therefore, if the difference between the first and second coordinates, which are the coordinates of the reflection point where the detection wave is reflected by the reflective surface, which is the curved surface of the vehicle body, is greater than a predetermined value, the vehicle can be distinguished from a small pole and identified as the controlled object.

In addition, in the above embodiment, the object detection unit 40 has four sensors, but the present disclosure is not limited to this, and any number of sensors may be included as long as there is at least one sensor capable of transmitting detection waves and two sensors capable of receiving detection waves. For example, as shown in FIG. 16, the object detection unit 40 has six wave transmitting and receiving sensors.

The six sensors are arranged with two in the center in the X direction, one at each end in the X direction, and one on each side of the vehicle 1. When the object detection unit 40 has six sensors, it is possible to increase the variety of combinations of round-trip paths of the detection wave compared to the configuration shown in FIG. 2.

In addition, in the above embodiment, the discrimination sensitivity is changed when the detection wave is reflected by two points on the object and received by the vehicle 1, but the present disclosure is not limited to this, and the discrimination sensitivity may be changed even when the detection wave is reflected by three or more points on the object and received by the vehicle 1. In this case, it is sufficient that the wave is received by three or more wave transmitting and receiving sensors.

In addition, in the above embodiment, identification control is performed when the detection wave is received by two wave transmission/reception sensors, but the present disclosure is not limited to this, and when the detection wave is received by one wave transmission/reception sensor, the identification threshold may be set to a first threshold value related to non-cylindrical objects to identify the object.

In addition, in the above embodiment, the object identification device (identification unit, shape determination unit, and modification unit) is incorporated into the vehicle control unit, but the present disclosure is not limited to this, and it does not have to be incorporated into the vehicle control unit.

In addition, the above embodiments are merely examples of concrete ways of implementing the present disclosure, and the technical scope of the present disclosure should not be interpreted in a limiting manner based on them. In other words, the present disclosure can be implemented in various forms without departing from its gist or main features.

In the object detection device of the above-mentioned embodiment and modified example, the notation "... part" used for each component may be replaced with other notations such as "... circuitry", "... assembly", "... device", "... unit", or "... module", as described above.

In addition, the object detection device of the above-described embodiment and modified example performs object detection processing by, for example, having the CPU 11 execute a program installed in the ROM 13.

However, the program executed by the object detection device may be provided as a file in an installable or executable format recorded on a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, or a digital versatile disk (DVD). Alternatively, the program may be downloaded via a network and executed by a computer.

In addition, at least a portion of the functionality of the object detection device may be realized by a dedicated hardware circuit that does not have a CPU.

In this way, the object detection device of the above-mentioned embodiment and modified example can be realized by software, hardware, or software in conjunction with hardware. In addition, the object detection device of the above-mentioned embodiment and modified example may be realized by a system, device, method, integrated circuit, computer program, or recording medium, or may be realized by any combination of a system, device, method, integrated circuit, computer program, and recording medium. Note that a program product is a computer-readable medium on which a computer program is recorded.

Furthermore, each functional block of the object detection device of the above-mentioned embodiment and modified example may be realized in part or in whole as an LSI, which is an integrated circuit, and each process of the object detection device of the above-mentioned embodiment and modified example may be controlled in part or in whole by one LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of one chip that includes some or all of the functional blocks. The LSI may have a data input and output. Depending on the degree of integration, the LSI may be called an IC, a system LSI, a super LSI, or an ultra LSI.

However, the method of integration is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacture, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells inside the LSI, may be used. Each process of the object detection device of the above-mentioned embodiment and modified example may be realized as digital processing or analog processing.

Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derived technologies, it is natural that such technology can be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

The object identification device disclosed herein is useful as an object identification device, vehicle, and object identification method capable of stably identifying objects.

REFERENCE SIGNS LIST 1 vehicle 10 acceleration section 20 braking section 30 vehicle speed information acquisition section 40 object detection section 41, 41a, 41b, 41c, 41d wave transmission/reception sensor 100 vehicle control unit 110 identification section 120 shape determination section 130 change section 140 area determination section 150 control section

Claims (12)

an area determination circuit that determines whether an object detected based on a detection wave transmitted and received by a sensor mounted on the moving body is located within a predetermined area in front of the moving body;
an identification circuit which, when it is determined by the area determination circuit that the object is located within the predetermined area, identifies whether or not the object is a controlled object based on a difference between a first coordinate of a first reflection point on the object of a detection wave received by the moving body at a first position at a first time and a second coordinate of a second reflection point on the object of a detection wave received by the moving body at a second position at a second time after the first time, and identifies the object as a non-controlled object when the difference between the first coordinate and the second coordinate is equal to or less than a predetermined value ;
An object identification device comprising: when the area determination circuit determines that the object is located within the predetermined area, the identification circuit determines whether or not the object is the controlled object based on time-series changes in coordinates of the object at three or more times.
The object identification device according to claim 1 . the identification circuit identifies the object as an uncontrolled object when the number of times the object has been determined to be an uncontrolled object is multiple;
The object identification device according to claim 1 or 2 . The predetermined area is an area spaced a predetermined width from a side surface of the moving body.
The object identification device according to any one of claims 1 to 3 . when an object located within the predetermined area is identified as an object other than the object to be controlled, the area determination circuit narrows the predetermined area so that the position of the object is outside the predetermined area.
The object identification device according to claim 4 . An object identification device according to any one of claims 1 to 5 ;
A sensor that transmits and receives the detection wave;
an object detection unit that detects the object based on the detection wave;
A mobile body comprising: 1. A method for identifying an object, comprising:
determining whether or not an object detected based on a detection wave transmitted and received by a sensor mounted on the moving body is located within a predetermined area in front of the moving body;
If it is determined that the object is located within the predetermined area,
identifying whether or not the object is a controlled object based on a difference between a first coordinate of a first reflection point on the object of a detection wave received by the moving body at a first position at a first time and a second coordinate of a second reflection point on the object of a detection wave received by the moving body at a second position at a second time after the first time ;
If the difference between the first coordinates and the second coordinates is equal to or smaller than a predetermined value, the object is identified as an uncontrolled object .
Object identification method. Whether the object is the controlled object or not is determined by
If it is determined that the object is located within the predetermined area, a determination is made based on time-series changes in coordinates of the object at three or more times.
The object identification method according to claim 7 . The object is
If the number of times that the object is determined to be an uncontrolled object is more than one, the object is identified as an uncontrolled object.
The object identification method according to claim 7 or 8 . The predetermined area is an area spaced a predetermined width from a side surface of the moving body.
The object identification method according to any one of claims 7 to 9 . When an object located within the predetermined area is identified as an object other than the controlled object, the predetermined area is narrowed so that the position of the object is outside the predetermined area.
The object identification method according to claim 10 . A sensor for transmitting and receiving detection waves;
an object detection unit that detects an object based on the detection wave;
A moving body comprising:
A moving body using the object identification method according to any one of claims 7 to 11 .

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