Vehicle radar system

• US 8,730,089 B2
• Filed: 07/14/2011
• Issued: 05/20/2014
• Est. Priority Date: 03/25/2011
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Shimizu, Yuji
• Primary Examiner(s): Sotomayor, John B
• Assistant Examiner(s): WINDRICH, MARCUS E
• Application Number:
  US13/183,095
• Publication Number:
  US 20120242529A1
• Time in Patent Office: 1,041 Days
• Field of Search: 342/27, 342/70, 342/85, 342107-109, 342/114
• US Class Current: 342/70
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles

Abstract

There are provided an object distinguishing unit that distinguishes an object every predetermined calculation cycle; and a state determination unit that determines a relative state between the object distinguished by the object distinguishing unit and a vehicle and that performs switching control in which based on the result of the determination, there is performed switching from one of a first angle detection unit and a second angle detection unit to the other in the next calculation cycle, and the value of an incident angle is inputted to the object distinguishing unit.

Claims

1. A vehicle radar system that is mounted in a vehicle, irradiates an electric wave toward a space in front of the vehicle, receives a reflected wave, which is originally the irradiated electric wave and has been reflected by an object in front of the vehicle, and detects the object, based on the received reflected wave, the vehicle radar system comprising:

a distance/relative speed detection unit that detects the distance and the relative speed between the vehicle and the object, based on the reflected wave;

a first angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a first plane parallel to a road surface on which the vehicle travels;

a second angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a second plane perpendicular to the first plane;

an object distinguishing unit that receives the values of the distance and the relative speed detected by the distance/relative speed detection unit and the value of the incident angle detected by one of the first angle detection unit and the second angle detection unit and that distinguishes the object for every predetermined calculation cycle, by use of these received values; and

a state determination unit that determines a relative state between the object distinguished by the object distinguishing unit and the vehicle and that performs switching control in which based on the detection of the object by one of the first angle detection unit and the second angle detection unit, there is performed switching from the one of the first angle detection unit and the second angle detection unit to the other in the next calculation cycle, and the value of the incident angle is inputted to the object distinguishing unit,

wherein in the case where a stationary object that is distinguished by the object distinguishing unit exists on a traveling track of the vehicle and a moving object exists at a position closer to the vehicle than the stationary object, the state determination unit performs the switching control in at least one of the following ways;

(1) switching from the first angle detection unit to the second angle detection unit is prohibited and the value of the incident angle detected only by the first angle detection unit is inputted to the object distinguishing unit, and (2) the rate of the calculation cycle in which the value of the incident angle detected by the first angle detection unit is utilized becomes larger than the rate of the calculation vie in which the value of the incident angle detected by the second angle detection unit is utilized.

2. A vehicle radar system that is mounted in a vehicle, irradiates an electric wave toward a space in front of the vehicle, receives a reflected wave, which is originally the irradiated electric wave and has been reflected by an object in front of the vehicle, and detects the object, based on the received reflected wave, the vehicle radar system comprising:

a distance/relative speed detection unit that detects the distance and the relative speed between the vehicle and the object, based on the reflected wave;

a first angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a first plane parallel to a road surface on which the vehicle travels;

a second angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a second plane perpendicular to the first plane;

an object distinguishing unit that receives the values of the distance and the relative speed detected by the distance/relative speed detection unit and the value of the incident angle detected by one of the first angle detection unit and the second angle detection unit and that determines every predetermined calculation cycle whether or not the object is a stationary object, by use of these received values; and

a state determination unit that performs switching control in which in accordance with the state of a relative position between the vehicle and a stationary object distinguished by the object distinguishing unit, there is performed switching from one of the first angle detection unit and the second angle detection unit to the other in the next calculation cycle, and the value of the incident angle is inputted to the object distinguishing unit, wherein in the case where a stationary object that is distinguished by the object distinguishing unit exists on a traveling track of the vehicle and the distance between the vehicle and the stationary object is smaller than a distance threshold value, the state determination unit performs the switching control in such a way that switching from the first angle detection unit to the second angle detection unit there is implemented, and the value of the incident angle is inputted to the object distinguishing unit.

3. The vehicle radar system according to claim 2, wherein the distance threshold value is a fixed distance threshold value that is preliminarily set.

4. The vehicle radar system according to claim 2, wherein the distance threshold value is a variable distance threshold value that is calculated based on a relative speed between the vehicle and a stationary object detected by the distance/relative speed detection unit.

5. A vehicle radar system that is mounted in a vehicle, irradiates an electric wave toward a space in front of the vehicle, receives a reflected wave, which is originally the irradiated electric wave and has been reflected by an object in front of the vehicle, and detects the object, based on the received reflected wave, the vehicle radar system comprising:

a distance/relative speed detection unit that detects the distance and the relative speed between the vehicle and the object, based on the reflected wave;

a first angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a first plane parallel to a road surface on which the vehicle travels;

a second angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a second plane perpendicular to the first plane;

an object distinguishing unit that receives the values of the distance and the relative speed detected by the distance/relative speed detection unit and the value of an incident angle of the reflected wave detected by one of the first angle detection unit and the second angle detection unit and that determines every predetermined calculation cycle whether or not the object is a stationary object, by use of these received values; and

a state determination unit that performs switching control in which in accordance with the state of a relative position between the vehicle and a stationary object distinguished by the object distinguishing unit, there is performed switching from one of the first angle detection unit and the second angle detection unit to the other in the next calculation cycle, and the value of the incident angle is inputted to the object distinguishing unit, wherein in the case where a stationary object that is distinguished by the object distinguishing unit exists on a traveling track of the vehicle, the state determination unit performs the switching control in such a way that the rate of the calculation cycle in which the value of the incident angle detected by the second angle detection unit is utilized becomes larger than the rate of the calculation cycle in which the value of the incident angle detected by the first angle detection unit is utilized, each time the distance between the vehicle and the stationary object becomes smaller than any one of a plurality of distance threshold values.

6. The vehicle radar system according to claim 5, wherein the distance threshold value is a fixed distance threshold value that is preliminarily set.

7. The vehicle radar system according to claim 5, wherein the distance threshold value is a variable distance threshold value that is calculated based on a relative speed between the vehicle and a stationary object detected by the distance/relative speed detection unit.

8. A vehicle radar system that is mounted in a vehicle, irradiates an electric wave toward a space in front of the vehicle, receives a reflected wave, which is originally the irradiated electric wave and has been reflected by an object in front of the vehicle, and detects the object, based on the received reflected wave, the vehicle radar system comprising:

a distance/relative speed detection unit that detects the distance and the relative speed between the vehicle and the object, based on the reflected wave;

a first angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a first plane parallel to a road surface on which the vehicle travels;

a second angle detection unit that detects an incident angle of the reflected wave having a direction along which there extends a second plane perpendicular to the first plane;

an object distinguishing unit that receives the values of the distance and the relative speed detected by the distance/relative speed detection unit and the value of an incident angle of the reflected wave detected by one of the first angle detection unit and the second angle detection unit and that determines every predetermined calculation cycle whether or not the object is a stationary object, by use of these received values;

an obstacle determination unit that determines whether or not a stationary object distinguished by the object distinguishing unit is an obstacle to the travel of the vehicle; and

a state determination unit that performs switching control in which in accordance with the state of a relative position between the vehicle and a stationary object distinguished by the object distinguishing unit, there is performed switching from one of the first angle detection unit and the second angle detection unit to the other in the next calculation cycle, and the value of the incident angle is inputted to the object distinguishing unit, wherein in the case where a stationary object that is distinguished by the object distinguishing unit exists on a traveling track of the vehicle, while the vehicle approaches the stationary object, the state determination unit performs the switching control in such a way that the switching between the first angle detection unit and the second angle detection unit is prohibited and the value of the incident angle detected only by the first angle detection unit is inputted to the object distinguishing unit, at a time point when the obstacle determination unit fixes determination, regardless of the result of the determination.