JP2008191910A - Navigation device, control method thereof, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cope with an abnormal state such as a slip due to the road surface freezing which has not been detected by a conventional technology, and to improve safety, by comparing a steering angle of a steering wheel according to the vehicle information with a vehicle rotation angle detected by a gyroscopic sensor of a navigation device, and by issuing a warning if the two angles deviate from a certain relationship range. <P>SOLUTION: An angle acquisition means 23 acquires a steering angle of a steering wheel from a vehicle computer 13, and acquires a vehicle rotation angle by a gyroscopic sensor 21. A comparison and detection means 30 compares the steering angle of the steering wheel with the rotation angle by the gyroscopic sensor, and if it detects that the two angles deviate from a certain relationship range as an inconsistency, a warning output means 31 outputs a warning by the display on the screen, a sound, and the like. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is an improvement of the technology related to navigation.

In recent years, in the field of so-called navigation devices, which have become widespread rapidly, information on the operation of the original mechanism of the vehicle (hereinafter referred to as “vehicle information”) is obtained from the vehicle, and danger is detected and used for warnings, etc. Ingenuity to improve has been proposed. One example is to detect a drowsy driving based on the rotation angle of the steering wheel (steering wheel) of the vehicle, that is, the steering angle, and while the vehicle is in the tunnel, it is identified and the sensitivity of the detection is switched. It has been proposed (see, for example, Patent Document 1).
JP 2001-163081 A

  By the way, the navigation device has information unique to the navigation device obtained by the navigation sensor group, in addition to the vehicle information as described above. However, conventionally, there is no proposal for utilizing such information in combination with the vehicle information as described above, and further improvement of safety by such utilization has been potentially desired.

  The present invention solves the above-described problems of the prior art, and its purpose is to compare the steering angle of the vehicle information with the vehicle rotation angle detected by the gyro sensor of the navigation device, and both are constant. By giving a warning when the relationship is broken, it is possible to cope with an abnormal state such as a slip due to road surface freezing, which could not be detected by the prior art, and to improve safety.

  Based on the above object, one embodiment of the present invention includes a gyro sensor for detecting a rotation angle of a vehicle, and obtains a steering angle of a steering wheel from the control computer in a navigation device connected to the vehicle control computer. In addition, the angle acquisition means for acquiring the rotation angle of the vehicle by the gyro sensor, and comparing the steering angle of the steering wheel and the rotation angle of the gyro sensor to detect that they are out of a predetermined relationship as a contradiction A detection means and a warning output means for outputting a warning when the contradiction is detected are realized by an arithmetic control unit of a computer.

  In this way, by comparing the steering angle of the vehicle information with the vehicle rotation angle detected by the gyro sensor of the navigation device and alerting the driver when a contradiction such as a direction mismatch occurs, It is possible to effectively cope with an abnormal state such as slip due to road surface freezing that could not be detected, thereby improving safety.

  In another aspect of the present invention, the comparison detection unit further detects the contradiction when the state where the steering angle and the rotation angle are out of the predetermined relationship continues for a predetermined time or more. And

  In this manner, by setting the lower limit value in advance during the time when the angle difference is occurring, it is possible to easily and reliably prevent malfunction due to temporary disturbance or signal noise.

  In another aspect of the present invention, the predetermined relationship is that the steering angle of the steering wheel and the rotation angle of the gyro sensor are in a proportional relationship within a predetermined range via a vehicle speed or a moving distance and a predetermined coefficient. It is characterized by being.

  In this way, by determining the discrepancy between the steering angle and the rotation angle, the vehicle speed and the coefficient are intervened, so that whether the axle angle is used as the steering angle or the holding angle of the steering wheel is used. It is possible to easily cope with various specifications on mounting, such as whether to use a specific angular velocity or an integral rotation amount.

  Another aspect of the present invention is characterized in that the comparison detection unit stops detecting the contradiction when the vehicle speed is zero.

  As described above, when the vehicle speed is zero and the vehicle is in a stopped state, detection of contradiction is stopped, so that erroneous reporting when a turntable such as a mechanical parking lot rotates can be effectively prevented.

  Note that the method and program also conform to the above-described embodiments.

  As described above, according to the present invention, the steering angle of the vehicle information is compared with the vehicle rotation angle detected by the gyro sensor of the navigation device, and a warning is given when both deviate from a certain relationship. It is possible to improve safety by dealing with abnormal conditions such as slips caused by road surface freezing that could not be detected by the prior art.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings. Note that assumptions common to the explanation in the background art and problems are omitted as appropriate.

[1. Constitution〕
As shown in the configuration diagram of FIG. 1, the present embodiment includes a gyro sensor 21 for detecting the rotation angle of the vehicle, and a control computer (referred to as a “vehicle computer”) 13 such as an ECU mounted on the vehicle. The present invention relates to a connected navigation device (hereinafter referred to as “this device”) 15.

[1-1. Steering angle sensor and vehicle computer)
First, although the vehicle computer 13 is not included in the present apparatus, the vehicle computer 13 includes a steering angle sensor 11, and the steering angle sensor 11 and the vehicle computer 13 are connected by a communication line 12 for information transmission. When the vehicle steering wheel (steering wheel) rotates, the steering angle sensor 11 converts the rotation angle of the steering wheel or the rotation angle of the wheel steering shaft into information (referred to as “steering angle information”) such as an electric signal for communication. It is transmitted to the vehicle computer 13 by the line 12. However, the communication line 12 may be configured to transmit a digital signal obtained by converting the rotation angle into a numerical value, or may be configured to transmit angle information as an analog signal as it is.

  Further, the vehicle computer 13 and the apparatus 15 are connected by a communication line 14 which is a bidirectional data communication means for exchanging information. The communication line 14 can be freely specified in details such as a communication form and a standard. A manufacturer's own in-vehicle LAN or general-purpose UART can be used. The vehicle computer 13 transmits the steering angle information to the device 15 through the communication line 14 in accordance with a predetermined communication format, command, and timing.

  As for the process of taking the information of the steering angle sensor 11 into the vehicle computer 13, a conventionally known technique is appropriately selected and used, such as the use of a sensor output movement integration process (see, for example, JP-A-8-255690). Also good.

[1-2. Information acquisition department)
In addition, the apparatus can be divided into an information capturing unit 2 that captures angle information and a comparison warning unit 3 that uses the captured information. Of these, the information capturing unit 2 includes the gyro sensor 21 and the information capturing unit 2. In addition to the A / D converter 22, the memory 24, and the buffer 25, the steering angle and the rotation angle are controlled by controlling a calculation control unit (CPU or the like) of a computer (not shown) with a predetermined control program prepared in advance. The angle acquisition means 23 for acquiring the above is realized.

  Among these, the gyro sensor 21 detects and expresses a rotational acceleration (angular acceleration) corresponding to the rotation angle when the vehicle on which the device 15 is mounted rotates while turning on a curve, right turn, left turn or the like. The rotation acceleration information is output as an analog signal, and the signal is converted into a digital signal by the A / D converter 22 and transmitted to the angle acquisition means 23.

  The angle acquisition means 23 is a processing means for realizing and executing the functions and operations of the present invention and this embodiment as will be described later, and the information transmitted as described above is stored in the memory 24 by processing in real time. At the same time, the rotation angle is calculated from the rotation acceleration using a conventionally known technique such as integration processing. In addition, the buffer 25 is configured such that the vehicle computer 13 communicates with the angle acquisition means 23 via the buffer 25 and transfers the steering wheel steering angle.

[1-3. Comparison warning section)
In addition, the comparison warning unit 3 compares the steering angle and the rotation angle acquired by the information capturing unit 2 with each other by controlling the calculation control unit of a computer (not shown) with the control program in accordance with the information capturing unit 2. The comparison detection means 30 for detecting and the warning output means 31 for outputting a warning are realized. These means 30 and 31 are also processing means for realizing and executing the functional actions of the present invention and this embodiment as will be described later. It is.

  The comparison warning unit 3 includes a monitor 33 for screen display such as a map, an image control unit 32 for controlling the display of the monitor 33, a nonvolatile memory 34 for storing warning sound data, and a D / A for sound output. It has a converter 35, an amplifier 36 and a speaker 37.

[2. (Overview of action)
In the present apparatus configured as described above, as an outline, the angle acquisition unit 23 acquires the steering angle of the steering wheel from the vehicle computer 13 and acquires the rotation angle of the vehicle by the gyro sensor 21. Then, the comparison and detection means 30 compares the steering angle of the steering wheel and the rotation angle of the gyro sensor, and if it is detected as a contradiction that the two have deviated from the predetermined relationship, the warning output means 31 displays a screen display or sound. Output a warning.

  In the present embodiment, the “steering angle” of the steering wheel may be a steering wheel, that is, a rotation angle of a steering wheel, or a steering angle of a wheel steering shaft obtained by multiplying this by a predetermined coefficient. The “relationship” between the steering angle and the rotation angle, which is used as a contradiction judgment criterion in the comparison detection means 30, is, as a simple example, between the steering angle as described above and the vehicle rotation angle per predetermined movement distance. This is a case where there is an angle difference greater than a predetermined allowable value.

[3. (Specific processing contents)
Hereinafter, a more specific processing procedure will be described with reference to the flowchart of FIG. 2. The processing procedure of this flowchart is repeatedly executed at a sufficiently short period close to real time. The processing contents include a steering angle and a rotation angle. This is an example of detecting a contradiction when a state out of the predetermined relationship as described above continues for a predetermined time or more.

[3-1. (Incorporation of steering angle information)
That is, after the control is started (step S41), the angle acquisition means 23 takes in the steering angle information representing the steering angle of the steering wheel of the vehicle from the vehicle computer 13 to the present apparatus 15 via the communication line 14 (step S42). Is stored in the memory 24 (step S43).

  Subsequently, the rotational angular velocity information representing the rotational angular velocity of the vehicle is fetched from the gyro sensor 21 (step S44) and stored in the memory (step S45), and the rotational angle ("" (Referred to as “gyro rotation angle”) (step S46).

[3-2. (Comparison of angle)
Subsequently, the comparison and detection means 30 compares the steering angle stored in the memory 24 (step S43) and the calculated gyro rotation angle (step S46) (step S47), and whether or not the two deviate from the predetermined relationship. For example, it is determined whether the angle difference is greater than or equal to a preset threshold value (step S48).

  Here, the preset threshold value is a value determined experimentally, and is determined in consideration of an error during travel, a swing width during travel of the vehicle, etc., but is preferably set so as not to react very sensitively. . This large angle difference means that the actual steering wheel rotation angle and the vehicle rotation angle are inconsistent, indicating that the vehicle tires are slipping due to road surface freezing or the like.

  That is, when the value is equal to or smaller than the threshold value (step S48), the process returns to the acquisition of the steering angle information (step S42). When the value is equal to or larger than the threshold value, 1 is added to the state count (step S49). In other words, if an immediate warning is given when it is determined that the threshold value is exceeded, there is a disadvantage that it reacts sensitively to slight vehicle movements, etc., so that the threshold value is continuously exceeded for a certain period (for example, a few seconds). Is determined by the number of counts that are periodically incremented.

  When the state count is 10 times or more (step S50), a warning is output (step S51). Here, the state count of 10 is an experimentally determined value, which may be determined in consideration of an error during traveling, a swing width during traveling of the vehicle, and the like, and should be set so as not to react very sensitively. Is desirable.

[3-3. Warning output)
In the warning output (step S51), the specific mode such as screen display or sound is free, but it is considered that the combination of the screen display and the sound output is typical. In this case, the warning output means 31 first appeals to the user's vision, so when the drawing content for the warning screen display is sent to the image control unit 32, the image control unit 32 performs necessary conversion processing such as bitmap drawing, The monitor 33 outputs and displays as an image for 10 seconds, for example.

  Further, the warning output means 31 extracts and decodes a warning sound such as ADPCM data or a warning voice phrase stored in advance in the nonvolatile memory 34 so as to appeal to the auditory sense, and decodes the decoded voice according to the digital audio signal format. The analog signal is transmitted to the D / A converter 35 and converted into an analog signal. The analog signal is amplified by the speaker output amplifier 36 and then output as a sound from the speaker 37 a predetermined number of times (for example, once).

[4. effect〕
As described above, in the present embodiment, the steering angle of the vehicle information is compared with the vehicle rotation angle detected by the gyro sensor of the navigation device, and the driver is warned when a contradiction such as a mismatch of directions occurs. As a result, it is possible to effectively cope with an abnormal state such as slip due to road surface freezing which could not be detected by the conventional technology, and improve safety.

  In this embodiment, as shown in steps S49 and S50 of FIG. 2 (flowchart), a malfunction is caused by temporary disturbance, signal noise, etc. by setting a lower limit value in advance during the time when the angle difference is occurring. Can be easily and reliably prevented.

[5. Other embodiments]
In addition, this invention is not limited to the said embodiment, The thing illustrated below and other embodiment other than that are included. For example, the warning display for 10 seconds is an example, and the driver may set an appropriate time sufficient for recognition.

In the above embodiment, the steering angle is compared with the gyro rotation angle per predetermined movement distance. However, the predetermined relationship between the angles in the contradiction detection is that the steering angle of the steering wheel and the gyro rotation angle are the vehicle speed or the movement. Whether there is a proportional relationship of a predetermined range via distance and a predetermined coefficient, for example,

Gyro rotation angle = steering angle × speed per hour × factor

Whether or not it can be judged.

  In this way, by determining the discrepancy between the steering angle and the rotation angle, the vehicle speed and the coefficient are intervened, so that whether the axle angle is used as the steering angle or the holding angle of the steering wheel is used. It is possible to easily cope with various specifications on mounting, such as whether to use a specific angular velocity or an integral rotation amount.

  Further, it is desirable that the comparison detection means is configured to stop detecting the angle contradiction when the vehicle speed obtained by the navigation device is zero based on the vehicle speed pulse or information from the CAN bus. As described above, when the vehicle speed is zero and the vehicle is in a stopped state, detection of contradiction is stopped, so that erroneous reporting when a turntable such as a mechanical parking lot rotates can be effectively prevented.

The figure which shows the structure of embodiment of this invention. The flowchart which illustrates the process sequence in embodiment of this invention.

Explanation of symbols

3 ... Comparison warning unit 11 ... Steering angle sensor 12 ... Communication line 13 ... Vehicle computer 14 ... Communication line 15 ... Navigation device 21 ... Gyro sensor 22 ... A / D converter 23 ... Angle acquisition means 24 ... Memory 25 ... Buffer 30 ... Comparison detection means 31 ... warning output means 32 ... image control unit 33 ... monitor 34 ... nonvolatile memory 35 ... D / A converter 36 ... amplifier 37 ... speaker

Claims (12)

In a navigation device including a gyro sensor for detecting a rotation angle of a vehicle and connected to a control computer of the vehicle,
An angle acquisition means for acquiring a steering angle of a handle from the control computer and acquiring a rotation angle of a vehicle by the gyro sensor;
Comparison detection means for comparing the steering angle of the steering wheel and the rotation angle of the gyro sensor and detecting that both of them are out of a predetermined relationship as a contradiction,
Warning output means for outputting a warning when the contradiction is detected;
Is realized by an arithmetic control unit of a computer.   The navigation device according to claim 1, wherein the comparison detection unit detects the contradiction when a state in which the steering angle and the rotation angle are out of the predetermined relationship continues for a predetermined time or more. The predetermined relationship is that the steering angle of the steering wheel and the rotation angle of the gyro sensor are in a proportional relationship within a predetermined range via a vehicle speed or a moving distance and a predetermined coefficient. 3. The navigation device according to 2.   The navigation device according to any one of claims 1 to 3, wherein the comparison detection unit stops detecting the contradiction when the vehicle speed is zero. In a control method of a navigation device that includes a gyro sensor for detecting a rotation angle of a vehicle and is connected to a control computer of the vehicle,
An angle acquisition unit that acquires a steering angle and a rotation angle by controlling an arithmetic control unit of the computer, a comparison detection unit that compares the steering angle and the rotation angle to detect an abnormality, and a warning output unit that outputs a warning , And
The angle acquisition means acquires the steering angle of the steering wheel from the control computer and acquires the rotation angle of the vehicle by the gyro sensor, and executes an angle acquisition process.
The comparison detection means compares the steering angle of the steering wheel with the rotation angle of the gyro sensor, and detects that both are out of a predetermined relationship as a contradiction,
A method for controlling a navigation device, wherein the warning output means executes warning output processing for outputting a warning when the contradiction is detected.   6. The navigation device control according to claim 5, wherein, in the comparison detection process, the contradiction is detected when a state in which the steering angle and the rotation angle are out of the predetermined relationship continues for a predetermined time or more. Method. The predetermined relationship is that the steering angle of the steering wheel and the rotation angle of the gyro sensor are in a proportional relationship within a predetermined range via a vehicle speed or a moving distance and a predetermined coefficient. 7. A method for controlling a navigation device according to 6.   The control method of the navigation device according to any one of claims 5 to 7, wherein in the comparison detection process, the detection of the contradiction is stopped when the vehicle speed is zero. In a control program for a navigation device that includes a gyro sensor for detecting a rotation angle of a vehicle and is connected to a vehicle control computer,
The program outputs an alarm by controlling an arithmetic control unit of the computer to obtain an angle acquisition unit that acquires a steering angle and a rotation angle, a comparison detection unit that compares the steering angle and the rotation angle, and detects an abnormality. Warning output means, and
The angle acquisition unit is configured to acquire a steering angle of a handle from the control computer, and to acquire a rotation angle of the vehicle by the gyro sensor.
The comparison detection means compares the steering angle of the steering wheel and the rotation angle of the gyro sensor and detects that both are out of a predetermined relationship as a contradiction,
A control program for a navigation device, characterized in that the warning output means outputs a warning when the contradiction is detected.   The navigation device control according to claim 9, wherein in the comparison detection process, the contradiction is detected when a state in which the steering angle and the rotation angle are out of the predetermined relationship continues for a predetermined time or longer. program. The predetermined relationship is that the steering angle of the steering wheel and the rotation angle of the gyro sensor are in a proportional relationship within a predetermined range via a vehicle speed or a moving distance and a predetermined coefficient. 10. A control program for a navigation device according to 10.   The control program for a navigation device according to any one of claims 9 to 11, wherein in the comparison detection process, the detection of the contradiction is stopped when the vehicle speed is zero.

Images