Peripheral object detection apparatus and peripheral object detection method
View Patent ↗A peripheral object detection apparatus that is installed in a vehicle to detect a peripheral object obstructing travel by a vehicle includes: a radar that obtains a reflection intensity by transmitting an electromagnetic wave and receiving an electromagnetic wave reflected by an object; and a determination unit that calculates an integrated value of an amount of variation in the reflection intensity within a predetermined section, obtained by the radar, and determines on the basis of the integrated value whether or not the object is a low object not obstructing travel by the vehicle.
1. A peripheral object detection apparatus that is installed in a vehicle to detect an obstacle obstructing travel by the vehicle, comprising:
a radar configured to obtain a reflection intensity by transmitting an electromagnetic wave and receiving an electromagnetic wave reflected by an object; and
a driver assist ECU configured to:
calculate a first integrated value comprising an integrated value of absolute values of differences in the reflection intensity within a predetermined section where values of reflection intensity are obtained by the radar,
calculate a base up amount of the reflection intensity within the predetermined section for each reflection point using a slope of the reflection intensity, and
determine on the basis of a second integrated value, obtained by subtracting the base up amount from the first integrated value, whether or not the object is a low object not obstructing travel by the vehicle.
2. The peripheral object detection apparatus according to claim 1 , wherein the driver assist ECU is configured to calculate at least one of a slope of the reflection intensity within the predetermined section where values of reflection intensity are obtained and a maximum value of an amount of variation in the reflection intensity within the predetermined section where values of reflection intensity are obtained, and determine whether or not the object is a low object on the basis of the second integrated value and the at least one of the slope and the maximum value.
3. The peripheral object detection apparatus according to claim 1 , wherein the driver assist ECU is configured to determine that the object is a low object when the second integrated value is smaller than a first threshold.
4. The peripheral object detection apparatus according to claim 3 , wherein the driver assist ECU is configured to calculate a slope of the reflection intensity within the predetermined section where values of reflection intensity are obtained, and determine that the object is a low object when the second integrated value is smaller than the first threshold and the slope is smaller than a second threshold.
5. The peripheral object detection apparatus according to claim 3 , wherein the driver assist ECU is configured to calculate a maximum value of an amount of variation in the reflection intensity within the predetermined section where values of reflection intensity are obtained, and determines that the object is a low object when the second integrated value is smaller than the first threshold and the maximum value is smaller than a second threshold.
6. The peripheral object detection apparatus according to claim 3 , wherein the driver assist ECU is configured to calculate a slope of the reflection intensity within the predetermined section where values of reflection intensity are obtained and a maximum value of an amount of variation in the reflection intensity within the predetermined section where values of reflection intensity are obtained, and determine that the object is a low object when the second integrated value is smaller than the first threshold, the slope is smaller than a second threshold, and the maximum value is smaller than a third threshold.
7. The peripheral object detection apparatus according to claim 1 , wherein the driver assist ECU is configured to determine that if the object is not a low object, the object is an obstacle obstructing travel by the vehicle.
8. The peripheral object detection apparatus according to claim 1 , wherein the low object is an object over which the vehicle can pass.
9. The peripheral object detection apparatus according to claim 1 , wherein the radar transmits and receives millimeter waves, and the predetermined section is a section in which millimeter waves traveling in a multipath environment can be sufficiently received by the radar when millimeter waves transmitted by the radar return after being reflected by an object.
10. The peripheral object detection apparatus according to claim 1 , wherein the predetermined section is a section in which the object can be detected before collision so that collision avoidance assist by a pre-crash system can be activated.
11. The peripheral object detection apparatus according to claim 1 , wherein the predetermined section is set in advance based on data obtained in an actual vehicle experiment.
12. A peripheral object detection method for detecting an obstacle obstructing travel by a vehicle, comprising:
obtaining a reflection intensity by transmitting an electromagnetic wave from a radar installed in the vehicle and receiving an electromagnetic wave reflected by an object;
calculating a first integrated value comprising an integrated value of absolute values of differences in the obtained reflection intensity within a predetermined section where values of reflection intensity are obtained;
calculating a base up amount of the reflection intensity within the predetermined section for each reflection point using a slope of the reflection intensity, and
determining on the basis of a second integrated value, obtained by subtracting the base up amount from the first integrated value, whether or not the object is a low object not obstructing travel by the vehicle.
13. The peripheral object detection method according to claim 12 , wherein obtaining a reflection intensity comprises transmitting a millimeter wave and receiving the millimeter wave reflected by the object; and
the predetermined section is a section in which millimeter waves traveling in a multipath environment can be sufficiently received by the radar when millimeter waves transmitted by the radar return after being reflected by an object.
14. The peripheral object detection method according to claim 12 , further comprising setting the predetermined section as a section in which the object can be detected before collision so that collision avoidance assist by a pre-crash system can be activated.
15. The peripheral object detection method according to claim 12 , further comprising setting the predetermined section in advance based on data obtained in an actual vehicle experiment.
16. The peripheral object detection method according to claim 12 , further comprising calculating a slope of the reflection intensity within the predetermined section of values of reflection intensity, and determining that the object is a low object when the second integrated value is smaller than a first threshold and the slope is smaller than a second threshold.
17. The peripheral object detection method according to claim 12 , further comprising calculating a maximum value of an amount of variation in the reflection intensity within the predetermined section of values of reflection intensity, and determining that the object is a low object when the second integrated value is smaller than a first threshold and the maximum value is smaller than a second threshold.
18. The peripheral object detection method according to claim 12 , further comprising calculating a slope of the reflection intensity within the predetermined section of values of reflection intensity and a maximum value of an amount of variation in the reflection intensity within the predetermined section of values of reflection intensity, and determining that the object is a low object when the second integrated value is smaller than a first threshold, the slope is smaller than a second threshold, and the maximum value is smaller than a third threshold.