Object detection apparatus

• US 10,453,343 B2
• Filed: 10/20/2015
• Issued: 10/22/2019
• Est. Priority Date: 10/22/2014
• Status: Active Grant

• Current Assignee: DENSO Corporation, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: DENSO Corporation
• Inventors: Fukuman, Masumi, Ohbayashi, Motonari, Kida, Akihiro
• Primary Examiner(s): Baghdasaryan, Hovhannes
• Application Number:
  US14/918,373
• Publication Number:
  US 20160116586A1
• Time in Patent Office: 1,463 Days
• CPC Class Codes: B60W 30/09 Taking automatic action to avoid collision, e.g. braking and steering
• CPC Class Codes: G01S 15/46 Indirect determination of position data
• CPC Class Codes: G01S 15/66 Sonar tracking systems
• CPC Class Codes: G01S 15/878 wherein transceivers are operated, either sequentially or simultaneously, both in bi-static and in mono-static mode, e.g. cross-echo mode
• CPC Class Codes: G01S 15/931 of land vehicles
• CPC Class Codes: G01S 2015/465 by Trilateration, i.e. two transducers determine separately the distance to a target, whereby with the knowledge of the baseline length, i.e. the distance between the transducers, the position data of the target is determined
• CPC Class Codes: G01S 2015/938 in the bumper area radar in bumper area G01S2013/93275; bumper with obstacle sensor of electric or electronic type B60R19/483
• CPC Class Codes: G08G 1/166 for active traffic, e.g. moving vehicles, pedestrians, bikes

Abstract

An object detection apparatus includes a first detection unit that detects an object based on a reflected version of probing waves transmitted by a first distance sensor and received as direct waves by the first distance sensor, a second detection unit that detects the object based on a reflected version of the probing waves received as indirect waves by a second distance sensor, a position calculation unit that calculates position data of the object using a trilateration method, a counter update unit that updates a counter value of a reliability level determination counter by an update amount, and an update amount setting unit that variably sets the value of the update amount depending on which position within detection areas of the first and second distance sensors the position data calculated in the current detection cycle shows the object to be in.

Claims

1. An object detection apparatus for detecting a presence of an object in a vicinity of a moving body which includes at least first and second object detection sensors, comprising:

a first detection unit that detects the object based on a reflected version of probing waves transmitted by the first object detection sensor and received as direct waves by the first object detection sensor;

a second detection unit that detects the object based on a reflected version of the probing waves received as indirect waves by the second object detection sensor;

a position calculation unit that calculates position data of the object based on detection results of the first and second detection units;

a counter update unit that updates a counter value of a reliability level determination counter by an update amount depending on the number of times that the first and second detection units have detected the object, the counter value being an index representing reliability of the position data; and

an update amount setting unit that variably sets a value of the update amount depending on which position within detection areas of the first and second object detection sensors the position data calculated in a current detection cycle shows the object to be in,

wherein the update amount setting unit is configured to set the update amount as a first positive value in response to the object being calculated to be in a first position, and to set the update amount as a second positive value in response to the object being calculated to be in a second position, the first positive value and the second positive value being different.

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

for each of the first and second object detection sensors, the detection area includes a stable detection area in which the object can be stably detected, and

the update amount setting unit sets the value of the update amount such that the reliability represented by the counter value of the reliability level determination counter becomes higher when the position of the object shown by the position data calculated in the current detection cycle is within the stable detection area than when the position of the object shown by the position data calculated in the current detection cycle is outside the stable detection area.

3. The object detection apparatus according to claim 1,

further comprising a location-success determination unit that determines whether or not a location method holds after transmission of the probing waves, the location method configured to calculate a measurement point based on a distance between two known points and distances from the two known points to the measurement point,

the update amount setting unit setting the value of the update amount such that the reliability represented by the counter value of the reliability level determination counter becomes higher when the location-success determination unit has determined that the location method holds than when the location-success determination unit has determined that the location method does not hold.

4. The object detection apparatus according to claim 1,

further comprising a position prediction unit that predicts the position of the object from a history of the position data calculated until a previous detection cycle, and a location-failure determination unit that determines whether or not the location method does not hold after transmission of the probing waves,

the update amount setting unit setting the value of the update amount depending on the position of the object predicted by the position prediction unit when the location-failure determination unit determines that the location method does not hold.

5. The object detection apparatus according to claim 4, wherein,

for each of the first and second object detection sensors, the detection area includes a stable detection area in which the object can be stably detected,

the object detection apparatus further comprises a predicted position determination unit that determines whether the position of the object predicted by the position prediction unit is within or outside the stable detection area, and

the update amount setting unit sets the value of the update amount such that, if the location-failure determination unit determines that the location method does not hold, the reliability represented by the counter value of the reliability level determination counter becomes lower when the position of the object predicted by the position prediction unit is within the stable detection area than when the position of the object predicted by the position prediction unit is outside the stable detection area.

6. The object detection apparatus according to claim 1, wherein the first and second object detection sensors are ultrasonic sensors which transmit ultrasonic waves as the probing waves.

7. The object detection apparatus according to claim 1, wherein the update amount setting unit is configured to set the update amount as a negative value or reset the counter value in accordance with the number of times both the direct waves and the indirect waves are not detected.

8. The object detection apparatus according to claim 1, wherein the update amount setting unit is configured to set the update amount as zero in accordance with the number of times only one of the direct waves and the indirect waves are detected.