JP3879610B2 - Obstacle detection device, program, and recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an obstacle detection apparatus, a program, and a recording medium that can detect obstacles around a vehicle by using ultrasonic waves.
[0002]
[Prior art]
Conventionally, as an obstacle detection device mounted on a vehicle, there is one using a plurality of ultrasonic sensors (sonar) that transmit ultrasonic waves.
In this obstacle detection device, ultrasonic waves are transmitted around the vehicle according to a predetermined order from a plurality of sonars mounted around the vehicle. Then, the reflected wave reflected by the ultrasonic wave hitting the obstacle or the like is received, and the presence or absence of the obstacle is determined by comparing the received wave with a threshold value. In addition, the distance from the obstacle is detected based on the time from transmission to reception of the ultrasonic wave.
[0003]
[Problems to be solved by the invention]
However, in the above-described technology, there is a possibility of erroneous detection only by detecting an obstacle once by sonar. Therefore, obstacle detection is performed by multiple transmissions / receptions. Had a problem that it took too much time to send and receive multiple times with all sonars.
[0004]
That is, in order to detect an obstacle, high detection accuracy and a short detection time are desired, but conventionally, the detection time is long and further improvement has been demanded.
The present invention has been made to solve the above-described problems, and its object is to achieve both high detection accuracy and short detection time when an obstacle is detected using a plurality of ultrasonic sensors. An object of the present invention is to provide an obstacle detection device, a program, and a recording medium.
[0005]
[Means for Solving the Problems and Effects of the Invention]
(1) The invention of claim 1 relates to an obstacle detection device for detecting obstacles around a vehicle by operating a plurality of ultrasonic sensors in a predetermined order, and in the present invention, When there is an ultrasonic sensor that detects the obstacle among the plurality of ultrasonic sensors, the predetermined predetermined value is set so that priority is given to the order of operation of the ultrasonic sensor that detects the obstacle. Control means for activating an ultrasonic sensor that detects the obstacle is provided every other order.
[0006]
That is, in the present invention, when there is an ultrasonic sensor which detects an obstacle, by changing the normal operating sequence, since the priority order of operation of the ultrasonic sensor that detected the obstacle, i.e. Since the ultrasonic sensor that detects the obstacle is operated every other predetermined sequence set in advance, the detection area corresponding to the ultrasonic sensor is quickly searched only several times necessary for detection accuracy. Can do. Thereby, both high detection accuracy and a short detection time can be realized.
[0012]
( 2) In the invention of claim 2 , when changing the operation order of the ultrasonic sensors, the ultrasonic sensors other than the ultrasonic sensors to be operated with priority are arranged in the predetermined order. It is characterized by operating.
For example, when the ultrasonic sensors A to D are normally operated in the order of A → B → C → D, when priority is given to the order of the ultrasonic sensor C, A → C → B → C → D → C In addition, the operation sequence of the ultrasonic sensor C is set during the normal sequence.
[0013]
As a result, it is possible to realize both the detection of obstacles in the entire surroundings and the reconfirmation of a specific obstacle.
( 3) The invention of claim 3 is characterized in that when the obstacle is no longer detected, the operation order of the ultrasonic sensors is returned to the predetermined order set in advance.
[0014]
The present invention exemplifies the operation sequence of the ultrasonic sensors when no obstacle is detected.
That is, in the present invention, when the obstacle is no longer detected, the operation order of the ultrasonic sensors is returned to a predetermined order, so that the detection of the obstacle around the vehicle is performed as usual. (Each ultrasonic sensor) can be performed quickly without interfering with each other.
[0015]
( 4) The invention according to claim 4 is characterized in that the operation interval of the ultrasonic sensor to be operated with priority is set to an interval of a predetermined time or more so as not to cause erroneous detection by its own ultrasonic wave.
In other words, if ultrasonic waves are transmitted and received by the same ultrasonic sensor in a short time, the ultrasonic waves interfere with each other to hinder obstacle detection. Therefore, in the present invention, the operation is performed within a range that does not hinder obstacle detection. Leave time. Thereby, an obstruction can be detected reliably.
[0016]
(5) The invention of claim 5 is a program for causing a computer to function as a control means in the obstacle detection apparatus according to any of the claims 1-4.
[0017]
(6) The invention of claim 6 is a computer-readable recording medium recording a program according to claim 5.
In the case of the program, for example, it can be used by recording it on a computer-readable recording medium such as a flexible disk, a magneto-optical disk, a CD-ROM, or a hard disk, and loading it into a computer system and starting it as necessary. In addition, the program may be recorded as a computer-readable recording medium such as a ROM or a backup RAM, and the ROM or the backup RAM may be incorporated into a computer system.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Examples of embodiments of the obstacle detection device, program, and recording medium of the present invention will be described below.
Example 1
The obstacle detection apparatus according to the present embodiment performs control to change the order of operation of the plurality of ultrasonic sensors according to whether or not an obstacle is detected.
[0019]
a) A basic configuration of the obstacle detection apparatus according to the present embodiment will be described with reference to FIGS.
As shown in FIG. 1, the obstacle detection device 1 of the present embodiment is a control device having a microcomputer (microcomputer) 3 as a main part. The microcomputer 3 is arranged at six locations around the vehicle. An ultrasonic sensor 5 and a storage device (for example, a memory such as an EEPROM) 7 for storing various data, setting values, and the like are connected.
[0020]
The microcomputer 3 is connected with a display device 9 for displaying the detection result of the obstacle, and a front alarm buzzer 11 and a rear alarm buzzer 13 for notifying the distance from the obstacle by sound.
Of these, the ultrasonic sensor 5 is shown in FIG. 2 (on the display surface of the display device 9) as indicated by the display lamps 5a to 5f. These sensors are arranged at a total of six locations, left and right, and transmit ultrasonic waves in a predetermined direction and receive the reflected waves.
[0021]
Specifically, as shown in FIG. 3, the left front corner sensor (FCL) is located on the left side of the front bumper 15, the right front corner sensor (FCR) is located on the right side of the front bumper 15, and the left side of the rear bumper 17. Left rear corner sensor (RCL), on the left side of the center of the rear bumper 17, back left sensor (RL), on the right side of the center of the rear bumper 17, back right sensor (RR), on the right side of the rear bumper 17, A right rear corner sensor (RCR) is disposed.
[0022]
And, an obstacle in the left front corner area of the vehicle diagonally left front is detected by the left front corner sensor (FCL), and an obstacle in the right front corner area of the vehicle diagonally right front of the vehicle is detected by the right front corner sensor (FCR). The left rear corner sensor (RCL) detects an obstacle in the left rear corner area diagonally left rear of the vehicle, and the back left sensor (RL) detects an obstacle in the back left area on the left rear side of the vehicle. The right sensor (RR) detects an obstacle in the back right area on the right rear side of the vehicle, and the right rear corner sensor (RCR) detects an obstacle in the right rear corner area on the right rear side of the vehicle.
[0023]
Thereby, an obstacle in each detection area around the vehicle can be detected.
b) Next, a method for detecting an obstacle by the obstacle detection apparatus 1 will be described.
[0024]
Here, as shown in FIG. 4, a case where an obstacle in the back right region is detected by the back right sensor (RR) will be described as an example.
(1) Main process This process is the entire process during system operation.
[0025]
As shown in the flowchart of FIG. 5, first, when the power is turned on, in step 100, the system is initialized. That is, the microcomputer 3 used in the obstacle detection apparatus 1 is initialized.
In the following step 110, the resource is initialized. That is, data such as a counter used for each process is initialized.
[0026]
In the following step 120, as will be described in detail later, an obstacle search process for detecting an obstacle by the ultrasonic sensor 5 is performed.
In the following step 130, a process for notifying the obstacle detected by the obstacle search process is performed.
[0027]
Specifically, the display lamps 5a to 5f corresponding to the position of the ultrasonic sensor 5 of the display device 9 are turned on (or flashing), and the front alarm buzzer 11 and the rear alarm buzzer corresponding to the position of the obstacle. Processing such as ringing 13 is performed.
(2) Obstacle Search Process This process is a process for operating the ultrasonic sensor 5 to detect an obstacle.
[0028]
As shown in the flowchart of FIG. 6, in step 200, it is determined whether or not it is a processing timing (for example, a timing of 20 ms) for operating the ultrasonic sensor 5 to detect an obstacle. If an affirmative determination is made here, the process proceeds to step 210. If a negative determination is made, the present process is temporarily terminated.
[0029]
In step 210, as will be described in detail later, a transmission / reception sensor determination process for determining the ultrasonic sensor 5 to be operated to detect an obstacle is performed.
In subsequent step 220, the ultrasonic sensor 5 determined in step 210 is operated to transmit ultrasonic waves and perform ultrasonic transmission / reception processing to receive the reflected waves.
[0030]
In subsequent step 230, it is determined whether there is an obstacle based on the received ultrasonic wave. If an affirmative determination is made here, the process proceeds to step 240, while if a negative determination is made, the process proceeds to step 260.
In step 240, since the obstacle is detected by the transmission / reception of the ultrasonic wave this time, the counter CSENSx set corresponding to the ultrasonic sensor operated this time, that is, the counter CSENSx that counts the number of times the obstacle has been detected. Is incremented (counted up).
[0031]
As shown in FIG. 7A, a predetermined detection sensor storage area A is set in the memory 7, and the detection sensor storage area A corresponds to each of the six ultrasonic sensors 5. Each counter CSENSx is stored.
The sensor No. in the detection sensor storage area A is a predetermined basic order (basic order) when the ultrasonic sensor 5 is operated, that is, the ultrasonic wave is not easily interfered with, and the surroundings of the vehicle are short-time. The order is to be searched. The basic order is a sequential search cycle in the order of “RL → FCR → RR → FCL → RCR → RCL”.
[0032]
In the following step 250, since the obstacle is detected by the ultrasonic sensor 5 operated this time, the sensor No. of the ultrasonic sensor (detection sensor) 5 that has detected the obstacle is shown in FIG. As shown, the data is stored in a predetermined detection sensor storage area B of the memory 7.
[0033]
Therefore, when there is a sensor No. stored in the detection sensor storage area B, it indicates that there is an obstacle in the detection area of the ultrasonic sensor 5.
If the sensor No. is not stored, no obstacle is detected.
[0034]
On the other hand, in step 260, since no obstacle is detected, the counter CSENSx corresponding to the ultrasonic sensor 5 operated this time is reset (set to 0). In the subsequent step 270, since no obstacle has been detected in the ultrasonic sensor 5 operated this time, the No. of the ultrasonic sensor 5 that has detected the obstacle is deleted from the detection sensor storage area B. This process ends.
[0035]
By the above-described processing, each time an obstacle is detected, the corresponding counter CSENSx is incremented. If no obstacle is detected, the data (sensor No. and counter CSENSx) is cleared, so according to the number of obstacles detected. In step 130 of FIG. 5, the obstacle can be notified with high accuracy.
[0036]
(3) Transmission / reception sensor determination process This process is a process for changing the order of the ultrasonic sensors 5 to be operated according to the detection state of the obstacle.
Here, prior to the description of this processing, first, a method of prioritizing the operation order of the detection sensors (that is, raising the priority order) will be described.
[0037]
As shown in FIG. 4, when an obstacle is detected by the back right sensor RR in the first search cycle, the operation sequence of each ultrasonic sensor 5 after the second operation of the back right sensor RR is performed. To change. That is, the priority of the operation of the back right sensor RR after that (after the third time) is raised.
[0038]
For example, (first time) “RL → FCR → RR (with detection) → FCL → RCR → RCL”, (second time) “RL → FCR → RR (second time operation) → FCL → RR → RRR → RR → RCL → RR ”, (from the third time)“ RL → RR → FCR → [RR] → FCL → RR → RCR → RR → RCL → RR. After the operation of (RR), the priority order of the detection sensors is increased so that the detection sensors are operated every other basic order.
[0039]
Note that the RR with an underline is given priority, and the [RR] shown in parentheses [] is the same as the case where priority is given (the same applies hereinafter).
Thus, normally, the same ultrasonic sensor 5 is activated every 120 ms, but when the priority is increased as in this case, the back right sensor (RR) which is the same ultrasonic sensor 5 is activated at 40 ms. When there are no obstacles, the normal basic order is restored.
[0040]
-Next, the process at the time of actually changing the order of the ultrasonic sensor 5 is demonstrated.
As shown in the flowchart of FIG. 8, in step 300, the sensor No. stores in the detection sensor storage area B shown in FIG. 7B whether there is an ultrasonic sensor 5 that has already detected an obstacle. Judgment is made based on whether or not If an affirmative determination is made here, the process proceeds to step 310, while if a negative determination is made, the process proceeds to step 320.
[0041]
In step 310, since an obstacle has already been detected, it is determined whether or not it is time to operate the ultrasonic sensor 5 in accordance with the basic order described above. If an affirmative determination is made here, the process proceeds to step 330, while if a negative determination is made, the process proceeds to step 370.
[0042]
That is, as described above, when the obstacle is detected by the back right sensor (RR), the operation timing of the back right sensor (RR) in the next search cycle is prioritized. It is determined whether there is any.
In step 330, since it is not time to prioritize the back right sensor (RR), the ultrasonic sensor 5 according to the basic order is determined as the ultrasonic sensor 5 to be activated. That is, the ultrasonic sensor 5 to be operated next is determined according to the counter CSENS indicating the basic order (counter indicating the sensor No.).
[0043]
In the following step 340, the counter CSENS is incremented.
In the following step 350, it is determined whether or not the counter CSENS is 6 or less, that is, whether or not one search cycle has been completed. Then, the process proceeds to step 360.
[0044]
In step 360, the counter CSENS is set to the first 1, and the process is temporarily terminated.
On the other hand, in step 370, which is determined to be negative in step 310 and is a timing for increasing the priority of the detection sensors, the detection sensor for increasing the priority is the same as the ultrasonic sensor 5 in the basic order (sequential transmission timing). It is determined whether or not the ultrasonic sensor 5 is the same. If an affirmative determination is made here, the process proceeds to step 390, whereas if a negative determination is made, the process proceeds to step 380.
[0045]
In step 390, since the basic order of the ultrasonic sensors 5 to be operated is the same as when the priority is raised (for example, [RR]), the basic order (the next operation is performed from the detection sensor storage area A). The ultrasonic sensor 5 to be determined is determined, and the process is temporarily terminated.
[0046]
On the other hand, in step 380, since the basic order of the ultrasonic sensor 5 to be operated is different from that in the case where the priority is raised (for example, because it is the RR ), the ultrasonic sensor 5 to be operated next from the detection sensor storage area B. As described above, the detection sensor (that is, the back right sensor (RR)) whose priority is to be increased is determined, and the present process is temporarily terminated.
[0047]
Therefore, the priority of detection sensors can be raised by the above-described processing.
c) Next, the effect of the obstacle detection apparatus 1 of the present embodiment will be described.
In the present embodiment, an obstacle is detected by operating a plurality of ultrasonic sensors 5 according to a basic order. When there is an ultrasonic sensor 5 that detects an obstacle, the obstacle is detected. The order of operation of the ultrasonic sensors 5 is changed, and the ultrasonic sensors 5 are preferentially operated.
[0048]
This preferentially searches for a detection area that may be an obstacle, so that there is an effect that the detection accuracy of the obstacle is increased.
Further, when the ultrasonic sensor 5 is simply operated according to a predetermined basic order, it takes a lot of time to operate the same ultrasonic sensor a plurality of times (for the purpose of increasing detection accuracy). However, in this embodiment, since the ultrasonic sensor 5 that has detected the obstacle is preferentially operated, it does not take much time even if the ultrasonic sensor 5 is operated a plurality of times.
[0049]
Therefore, in this embodiment, there is a remarkable effect that both high detection accuracy and short detection time can be realized.
(Example 2)
Next, the second embodiment will be described, but the description of the same parts as the first embodiment will be omitted.
[0050]
In this embodiment, as shown in FIG. 9, an example in which an obstacle is detected in the back left (RL) region and the left rear corner (RCL) region will be described.
First, an obstacle is usually detected by repeating a search cycle of “RL → FCR → RR → FCL → RCR → RCL”.
[0051]
Here, (first time) “RL → FCR → RR → FCL → RCR → RCL (with detection)”, (second time) “RL (with detection) → FCR → RR → FCL → RR → RCR → RR → RCL ( Consider the case of “second detection)”.
In this case (from the third time) “RL (second detection) → FCR → RCL → RR → RL → FCL → RCL → RCR → RL → [RCL] → [RL] → FCR → RCL → RR → RL → FCL → RCL → RCR → RL ... After the second detection sensor operation, the detection sensor order is set every other basic order.
[0052]
In particular, in this embodiment, since there are two detection sensors, the left rear corner sensor (RCL) that has detected an obstacle first has priority over the back left sensor (RL) that has detected an obstacle later, and both detections are made. Increase sensor priority.
If there is no obstacle in the left rear corner (RCL) area, the priority order of the left rear corner sensor (RCL) is restored, and similarly, there is no obstacle in the back left (RL) area. Restores the priority of the back left sensor (RL).
[0053]
In this embodiment, when the priority is raised as described above, the back left sensor (RL transmission interval is shortened from the normal 120 ms to 80 ms (partly 40 ms). The transmission interval of (RCL) is shortened from the usual 120 ms to 80 ms (partially 60 ms).
[0054]
In the present embodiment, even when an obstacle is detected in a plurality of detection areas, as in the first embodiment, both a high detection accuracy and a short detection time can be realized.
(Example 3)
Next, although Example 3 will be described, description of the same parts as those in Example 1 will be omitted.
[0055]
In this embodiment, as shown in FIG. 10, an example in which an obstacle is detected in the left front corner (FCL) region and the back left (RL) region will be described.
First, an obstacle is usually detected by repeating a search cycle of “RL → FCR → RR → FCL → RCR → RCL”.
[0056]
Here, (first time) “RL → FCR → RR → FCL (with detection) → RCR → RCL”, (second time) “RL (with detection) → FCR → RR → FCL (second detection) → RCR → FCL Consider the case of “→ RCL”.
In this case (from the third time) “ FCL → RL (second detection) → FCL → FCR → RL → FCL → RCL → RCR → RL → [RCL] → [RL] → FCR → RCL → RR → RL → RR → [FCL] → RCR → RL → RCR → FCL → [RL] → FCL → FCR → RL → RR → [FCL] → RCR → RL → RCL → FCL ... After operation, the order of detection sensors is set every other basic order.
[0057]
In particular, in this embodiment, since there are two detection sensors, the left front corner (FCL) that previously detected the obstacle has priority over the back left sensor (RL) that subsequently detected the obstacle, and both detection sensors Increase priority.
When there is no obstacle in the left front corner (FCL) area, the priority order of the left front corner sensor (FCL) is restored, and similarly, when there is no obstacle in the back left (RL) area, The priority order of the back left sensor (RL) is restored.
[0058]
In the present embodiment, when the priority is raised as described above, the transmission interval of the back left sensor (RL) is shortened from the normal 120 ms to 80 ms (partly 60 ms). Further, the transmission interval of the left front corner sensor (FCL) is shortened from the usual 120 ms to 80 ms (partly 40 ms).
[0059]
In the present embodiment, even when an obstacle is detected in a plurality of detection areas, as in the first embodiment, both a high detection accuracy and a short detection time can be realized.
Needless to say, the present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the scope of the present invention.
[0060]
(1) For example, when detecting the distance to an obstacle, the priority order can be increased as the distance from the obstacle is shorter.
For example, when there are a plurality of ultrasonic sensors that detect an obstacle, the priority order can be increased as the ultrasonic sensor has a shorter distance from the obstacle.
[0061]
Thereby, when an obstacle is detected near the vehicle, the presence of the obstacle can be confirmed promptly. Therefore, it is possible to set the optimum detection state by comparing the importance of the detection of the obstacles in the entire surroundings and the reconfirmation of the specific obstacle. (2) For example, in the first to third embodiments, the obstacle detection apparatus has been described. However, the present invention is not limited thereto, and the present invention can be applied to a program for executing processing based on the above-described algorithm and a recording medium storing the program. .
[0062]
Examples of the recording medium include various recording media such as an electronic control device configured as a microcomputer, a microchip, a flexible disk, a hard disk, and an optical disk. That is, there is no particular limitation as long as it stores a program that can execute the processing of the obstacle detection device described above.
[0063]
The program is not limited to a program stored in a recording medium, but can be applied to a program transmitted / received through a communication line such as the Internet.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram illustrating a system configuration of an obstacle detection apparatus according to a first embodiment.
FIG. 2 is an explanatory diagram illustrating a display device according to a first embodiment.
FIG. 3 is an explanatory diagram illustrating each ultrasonic sensor and its detection area according to the first embodiment.
FIG. 4 is an explanatory diagram illustrating a case where an obstacle is detected by a back right sensor (RR) according to the first embodiment.
FIG. 5 is a flowchart illustrating main processing according to the first exemplary embodiment.
FIG. 6 is a flowchart illustrating obstacle search processing according to the first embodiment.
7A and 7B show storage contents of a memory according to the first embodiment, where FIG. 7A is an explanatory diagram showing the contents of a storage area A, and FIG.
FIG. 8 is a flowchart illustrating transmission / reception sensor determination processing according to the first embodiment.
FIG. 9 is an explanatory diagram illustrating a case where an obstacle is detected by a back left sensor (RL) and a left rear corner sensor (RCL) according to the second embodiment.
FIG. 10 is an explanatory diagram showing a case where an obstacle is detected by a left front corner sensor (FCL) and a back left sensor (RL) according to a third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Obstacle detection apparatus 3 ... Microcomputer 5 ... Ultrasonic sensor 7 ... Memory | storage device 9 ... Display apparatus 11 ... Front alarm buzzer 13 ... Back alarm buzzer FCL ... Left front corner sensor FCR ... Right front corner sensor RCL ... Left rear corner sensor RL ... Back left sensor RR ... Back right sensor RCR ... Right rear corner sensor

Claims (6)

In the obstacle detection device for detecting obstacles around the vehicle by operating a plurality of ultrasonic sensors in a predetermined order set in advance,
When there is an ultrasonic sensor that detects the obstacle among the plurality of ultrasonic sensors, the predetermined predetermined value is set so that priority is given to the order of operation of the ultrasonic sensor that detects the obstacle. An obstacle detection apparatus comprising control means for operating an ultrasonic sensor that detects the obstacle in every other order . The ultrasonic sensor other than the ultrasonic sensor to be operated with priority is operated in the predetermined order when the order of operation of the ultrasonic sensors is changed. obstacle detection device according to 1. 3. The obstacle detection apparatus according to claim 1, wherein when the obstacle is no longer detected, the operation order of the ultrasonic sensors is returned to the predetermined order set in advance. 4. Working distance of the ultrasonic sensor for actuating said preferentially, as not to cause erroneous detection by its ultrasound, according to any of the claims 1-3, characterized in that the predetermined or more hour intervals Obstacle detection device. The program for functioning a computer as a control means in the obstacle detection apparatus in any one of the said Claims 1-4 . Computer readable recording medium recording a program according to claim 5.

Images