Object detection device and recording medium

1. An object detection device comprising:

a processor; and

a memory storing instructions that, when executed by the processor, cause the object detection device to:

receive, from a radar device that transmits a transmission wave and receives a reflected wave that is the transmission wave reflected by an object around a subject vehicle, detection result information indicative of an intensity, an azimuth, and a Doppler velocity of the reflected wave, the Doppler velocity being a velocity obtained from a Doppler frequency shift of the reflected wave, and determine whether the detection result information is first detection result information corresponding to a moving object or second detection result information corresponding to a still object;

calculate distances from the radar device to respective reflection points of the moving object based on the first detection result information;

supply, to a predetermined device, first reflection point information indicative of the distances of the respective reflection points of the moving object and azimuths of the respective reflection points of the moving object based on the radar device;

determine that the first reflection point information is to be supplied to the predetermined device in a case where the moving object is determined to be closer to the radar device than the still object based on second reflection point information indicative of the distances of the respective reflection points of the still object and azimuths of the respective reflection points of the still object viewed from the radar device and the first reflection point information;

determine whether a density of the reflection points of the still object per unit azimuth is equal to or higher than a predetermined threshold value based on the second reflection point information,

wherein the distances from the radar device to respective reflection points of the still object are determined based on the second detection result information, and

wherein the second reflection point information is supplied for determining whether the moving object is closer to the radar device than the still object in a case where the density of the reflection points is equal to or higher than the threshold value, and the second reflection point information is not supplied for determining whether the moving object is closer to the radar device than the still object in a case where the density of the reflection points is less than the threshold value.

2. The object detection device according to claim 1 , wherein

the instructions, when executed by the processor, cause the object detection device to determine that the detection result information is the second detection result information in a case where the azimuth of the reflected wave is an angle θ with respect to a traveling direction of the subject vehicle and where the Doppler velocity is a product of a velocity of the subject vehicle and cos θ.

3. The object detection device according to claim 1 , wherein the instructions, when executed by the processor, cause the object detection device to perform interpolation on the distances of the respective reflection points of the moving object indicated by the first reflection point information based on a distance of a reflection point present at an azimuth shifted by a predetermined angle from a right-angled direction that crosses at right angles with a traveling direction of the subject vehicle in a case where the moving object is present in the right-angled direction with respect to the traveling direction of the subject vehicle.

4. The object detection device according to claim 1 , wherein the instructions, when executed by the processor, cause the object detection device to determine that moving object type information indicative of a type of moving object corresponding to a shape having a highest degree of matching is to be supplied to the predetermined device together with the first reflection point information based on a shape of a plurality of reflection points indicated by the first reflection point information and pattern information indicative of shapes of respective predetermined types of moving objects.

5. The object detection device according to claim 1 , wherein the instructions, when executed by the processor, cause the object detection device to receive the first reflection point information indicative of Doppler velocities of the respective reflection points of the moving object at a predetermined time interval,

calculate, based on the Doppler velocities indicated by the first reflection point information received at a first timing and the time interval, predicted positions of the respective reflection points of the moving object at a second timing that is later than the first timing; and

smooth positions of the respective reflection points indicated by the first reflection point information received at the second timing based on the predicted positions.

6. The object detection device according to claim 5 , wherein

the instructions, when executed by the processor, cause the object detection device to calculate, based on the Doppler velocities of a plurality of reflection points of the moving object, the predicted positions of the respective reflection points of the moving object.

7. A non-transitory computer-readable recording medium storing a program causing a computer to:

receive, from a radar device that transmits a transmission wave and receives a reflected wave that is the transmission wave reflected by an object around a subject vehicle, detection result information indicative of an intensity, an azimuth, and a Doppler velocity of the reflected wave, the Doppler velocity being a velocity obtained from a Doppler frequency shift of the reflected wave, and determine whether the detection result information is first detection result information corresponding to a moving object or second detection result information corresponding to a still object;

calculate distances from the radar device to respective reflection points of the moving object based on the first detection result information; and

supply, to a predetermined device, reflection point information indicative of the distances of the respective reflection points of the moving object and azimuths of the respective reflection points of the moving object based on the radar device;

determine that the first reflection point information is to be supplied to the predetermined device in a case where it was determined that the moving object is closer to the radar device than the still object based on second reflection point information indicative of the distances of the respective reflection points of the still object and azimuths of the respective reflection points of the still object viewed from the radar device and the first reflection point information;

determine whether a density of the reflection points of the still object per unit azimuth is equal to or higher than a predetermined threshold value based on the second reflection point information;

calculate distances from the radar device to respective reflection points of the still object based on the second detection result information; and

supply the second reflection point information for determining whether the moving object is closer to the radar device than the still object in a case where the density of the reflection points is equal to or higher than the threshold value, and not supply the second reflection point information for determining whether the moving object is closer to the radar device than the still object in a case where the density of the reflection points is equal to or higher than the threshold value in a case where the density of the reflection points is less than the threshold value.