JP2012098117A - Abnormality detection device and abnormality detection program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve detection of abnormality of an obstacle detection device with a simple process in an abnormality detection device for detecting abnormality of the obstacle detection device.SOLUTION: A radar sensor includes a signal processing unit which detects a deflection amount represented by an angle formed by a relative movement vector of an own vehicle and a direction of a central axis obtained before the start of present process and corrects the direction of the central axis so that the deflection amount approaches 0. Then, utilizing the direction of the corrected central axis, the signal processing unit detects the deflection amount again to correct the direction of the central axis so that the deflection amount approaches 0 even further. By repeating the aforementioned process, the deflection amount converges to 0 gradually. In this configuration, the radar sensor is determined to have an abnormality when a changing pattern of the deflection amount deviates from a reference pattern which is set in advance (S210 to S230).

Description

  The present invention relates to an abnormality detection device that detects an abnormality of an obstacle detection device that is mounted on a vehicle, emits a predetermined transmission wave, and detects an obstacle based on the reflected wave, and an abnormality detection program.

  As the abnormality detection device, one that detects dirt on a receiving surface that receives a reflected wave is known (see, for example, Patent Document 1). In this abnormality detection device, each of the receiving units having a plurality of channels receives reflected waves, and the deviation between the power in the channel where the received power based on the input reflected waves is maximum and the power in other channels exceeds the threshold. If the reception surface is dirty, it is determined that the receiving surface is dirty.

JP 2009-192442 A

  However, the above-described abnormality detection apparatus has a problem in that it is necessary to sequentially compare the received powers of all channels in order to detect an abnormality such as dirt on the reception surface, and the processing at this time becomes complicated.

  Therefore, in view of such problems, simple processing is performed in the abnormality detection device and the abnormality detection program for detecting an abnormality in the obstacle detection device that irradiates a predetermined transmission wave and detects an obstacle based on the reflected wave. The first object is to enable detection of an abnormality in the abnormality detection device, and the second object is to improve the detection speed when detecting an abnormality.

  In the abnormality detection device of the first configuration configured to achieve the object, the reception signal acquisition unit acquires a reception signal based on the reflected wave, and the obstacle detection unit preliminarily receives the central axis recording unit from the reception signal. The angle at which the obstacle is located with respect to the direction of the central axis and the distance to the obstacle are repeatedly detected. Then, the deflection amount detection means repeatedly detects the deflection amount that is an angle formed by the relative movement vector of the host vehicle with respect to the obstacle and the direction of the central axis, and the correction amount calculation means detects the deflection amount so that the deflection amount approaches zero. The correction amount for correcting the deflection amount in a plurality of times is repeatedly calculated.

  Further, the recording control means records the central axis as the new central axis direction obtained by correcting the central axis direction by the correction amount as the central axis direction used when the obstacle detecting means detects the obstacle. The deflection amount recording means causes the history recording unit to record the deflection amount or the parameter linked to the deflection amount as a history. The first abnormality determination means determines that the obstacle detection device is abnormal when the deflection amount or the parameter change pattern linked to the deflection amount deviates from a preset reference pattern.

  That is, in the present invention, a deflection amount that is an angle formed by the relative movement vector of the host vehicle and the direction of the central axis obtained until the start of the current process is detected, and the central axis is adjusted so that this deflection amount approaches zero. Correct the direction. Then, using the corrected direction of the central axis, the deflection amount is detected again, and the direction of the central axis is corrected so that the deflection amount further approaches zero. By repeating such processing, the deflection amount is converged to zero in a stepwise manner.

  In such a configuration, when there is no abnormality in the abnormality detection device, it is expected that a deflection amount change pattern is obtained such that the deflection amount approaches 0 with a predetermined number of repetitions. On the other hand, when there is an abnormality such as dirt in the abnormality detection device, it is considered that a change pattern of the deflection amount different from that when there is no abnormality is obtained. Therefore, in the present invention, a change pattern that is expected to be obtained when there is no abnormality is held as a reference pattern, and when the deflection amount or the parameter change pattern linked to the deflection amount deviates from this reference pattern, It is determined that there is an abnormality in the detection device.

  According to such an abnormality detection device, in a configuration in which the direction of the central axis is corrected so that the deflection amount approaches zero in steps, the deflection amount (or a parameter linked to the deflection amount) is recorded, and this change pattern is recorded. An abnormality of the abnormality detection device can be detected only by comparing with the reference pattern. Therefore, the abnormality of the abnormality detection device can be detected with a simple process.

  By the way, in the above-described abnormality detection device, as in the abnormality detection device of the second configuration, the first abnormality determination means detects an abnormality when the deflection amount or the parameter linked to the deflection amount increases with time. You may make it determine with there.

According to such an abnormality detection device, it can be determined that there is an abnormality when the amount of deflection that should approach 0 increases with time.
In the abnormality detection device, as in the abnormality detection device of the third configuration, the first abnormality determination means uses the corrected deflection amount or a reference change rate in which a parameter linked to the corrected deflection amount is set in advance. You may make it determine with it being abnormal when it changes exceeding.

  According to such an abnormality detection device, even if the deflection amount approaches 0 as time passes, it is determined that the change is abnormal when the change rate at this time exceeds the reference change rate and is abnormally large. Can do.

  Further, in the abnormality detection device, as in the abnormality detection device of the fourth configuration, the deflection amount or the history of parameters linked to the deflection amount is deleted when the power supply of the abnormality detection device is turned off. When the first abnormality determining means determines that there is an abnormality, there is an abnormality recording means that records that there is an abnormality, and when there is an abnormality recorded, there is a history and an abnormality Protection means for protecting the effect from being deleted.

According to such an abnormality detection device, since the history is not deleted when an abnormality occurs, the cause when the abnormality occurs can be easily clarified by the history.
Further, in the abnormality detection device, as in the abnormality detection device of the fifth configuration, the reception signal acquisition means includes a plurality of obstacle detection devices having a plurality of reception channels for receiving reflected waves by different antenna elements. Received reception signals for each receiving channel, and whenever receiving signals are obtained from multiple receiving channels, the largest receiving signal power value is extracted from the receiving channels as the maximum channel, and the maximum for each receiving channel. If there is a deviation calculating means for calculating the deviation of the power value from the channel and a receiving channel where the deviation calculated by the deviation calculating means is greater than or equal to a preset candidate threshold, the abnormality determination value is incremented. It is determined that there is an abnormality in the obstacle detection device when the determination value counting means and the abnormality determination value are equal to or greater than a preset abnormality determination threshold value. A second abnormality determination unit may include a.

According to such an abnormality detection device, it can be determined that there is an abnormality even when a state in which the deviation of the received power is large continuously occurs.
Further, in the abnormality detection device, as in the abnormality detection device of the sixth configuration, when it is determined that there is an abnormality by the first abnormality determination unit, a threshold value changing unit that changes the abnormality determination threshold value to a smaller value; May be provided.

  According to such an abnormality detection device, when an abnormality is detected by the first abnormality determination unit, it is possible to shorten the time until the second abnormality determination unit determines that an abnormality has occurred.

  Further, the abnormality detection device includes abnormality output means for outputting an abnormality when the second abnormality determination means determines that there is an abnormality, like the abnormality detection device of the seventh configuration. May be.

  According to such an abnormality detection device, it can be output that there is an abnormality by the second abnormality determination means. And if the determination result by a 1st abnormality determination means is hold | maintained like the 4th structure, it can make it easy to identify the cause of abnormality.

  In the above-described abnormality detection device, as in the abnormality detection device of the eighth configuration, the deflection amount detection means repeatedly detects the deflection amount in which the latest deflection amount is added to the deflection amount detected in the past. Good.

  According to such an abnormality detection device, since the deflection amount is detected in consideration of the deflection amount detected in the past, it is abnormal when the deflection amount temporarily changes greatly due to the influence of noise or vibration. Can be prevented from being erroneously detected.

  Further, the program for achieving the above object is an abnormality detection program for causing a computer to function as each means constituting the abnormality detection device according to any one of the above items.

  According to such an abnormality detection program, at least the same effect as that of the abnormality detection device according to claim 1 can be enjoyed.

It is a block diagram which shows the structure of the vehicle control system to which invention was applied. It is an external view of a radar sensor. It is explanatory drawing which shows the transmission timing of a radar wave. It is a flowchart which shows an axial deviation correction process. It is explanatory drawing about axial deviation | shift amount (theta). It is a flowchart which shows an abnormality detection process. 6 is a graph showing a history of θshift.

Embodiments according to the present invention will be described below with reference to the drawings.
[Entire configuration of this embodiment]
FIG. 1 is a block diagram showing a schematic configuration of a vehicle control system 1 to which the present invention is applied.

  As shown in FIG. 1, the vehicle control system 1 includes a radar sensor 3 (obstacle detection device, abnormality detection device) that detects an object that is installed in front of the vehicle and is located within a predetermined detection range in front of the vehicle. Yes. The radar sensor 3 is connected to an inter-vehicle control electronic control device (hereinafter referred to as “inter-vehicle control ECU”) 30, and the inter-vehicle control ECU 30 is connected to an engine electronic control device (hereinafter referred to as “engine ECU”) via a LAN communication bus. ) 32, and various ECUs such as a brake electronic control unit (hereinafter referred to as “brake ECU”) 34. Each ECU is configured around a known microcomputer and includes at least a bus controller for performing communication via a LAN communication bus.

  The radar sensor 3 is configured as a so-called “millimeter wave radar” of the FMCW system, and transmits / receives a frequency-modulated millimeter wave band radar wave to thereby obstruct various objects (preceding vehicles, roadside objects, etc.). ), And based on these recognition results, target information relating to a preceding vehicle traveling ahead of the host vehicle and diagnostic information indicating the state of the radar sensor 3 are created and transmitted to the inter-vehicle control ECU 30. The target information includes at least the relative speed with respect to the preceding vehicle and the position (distance, azimuth) of the preceding vehicle, and the diagnosis information includes detection performance based on abnormalities such as dirt on the radar wave receiving surface. The information which shows the presence or absence of fall of is contained at least.

  The brake ECU 34 transmits the brake pedal state determined based on information from an unillustrated M / C pressure sensor to the inter-vehicle control ECU 30 in addition to detection information (steering angle, yaw rate) from an unillustrated steering sensor and yaw rate sensor. Receiving a target acceleration, a brake request, etc. from the inter-vehicle control ECU 30, and driving a brake actuator for opening and closing a pressure increase control valve / a pressure reduction control valve provided in the brake hydraulic circuit according to the received information and the determined brake state It is configured to control the braking force with.

  The engine ECU 32 transmits detection information (vehicle speed, engine control state, accelerator operation state) from a vehicle speed sensor, a throttle opening sensor, and an accelerator pedal opening sensor (not shown) to the inter-vehicle control ECU 30, and the inter-vehicle control ECU 30 receives a target acceleration. Driving the internal combustion engine by receiving a fuel cut request or the like and outputting a drive command to a throttle actuator or the like that adjusts the throttle opening of the internal combustion engine according to the operating state specified from the received information Configured to control force.

  The inter-vehicle control ECU 30 receives target information and diagnostic information from the radar sensor 3, vehicle speed and engine control state from the engine ECU 32, steering angle, yaw rate, brake control state and the like from the brake ECU 34. In addition, the inter-vehicle control ECU 30 adjusts the inter-vehicle distance to the preceding vehicle to an appropriate distance based on setting values by a cruise control switch, a target inter-vehicle setting switch, etc. (not shown) and target information received from the radar sensor 3. As a control command, a target acceleration, a fuel cut request, and the like are transmitted to the engine ECU 32, and a target acceleration, a brake request, and the like are transmitted to the brake ECU 34.

  Further, when the diagnosis information received from the radar sensor 3 indicates that the detection performance is degraded, processing for prohibiting or restricting the use of the target information from the radar sensor 3 is executed.

[Appearance of radar sensor]
Here, FIG. 2 is an external view of the radar sensor 3.
As shown in FIG. 2, the radar sensor 3 is arranged so as to cover a box-shaped housing 3a having an opening portion for accommodating a circuit element and an opening portion of the housing 3a, and an antenna for transmitting and receiving radar waves is arranged. And a radome 3c that is formed of a resin that transmits radar waves and is attached to the housing 3a so as to cover the antenna substrate 3b. FIG. 2 shows a state in which the radome 3c is removed, with the housing 3a and the antenna substrate 3b being a perspective view, and the radome 3c being a plan view.

The radar sensor 3 is attached outside the passenger compartment such as a front bumper with the attachment surface of the radome 3c (that is, the transmission / reception surface of the radar wave) facing the radiation direction of the radar wave.
[Detailed configuration of radar sensor]
Here, a detailed configuration of the radar sensor 3 will be described.

  As shown in FIG. 1, the radar sensor 3 outputs a high-frequency signal in the millimeter wave band that is modulated so as to have an up section in which the frequency increases linearly and a down section in which the frequency decreases linearly. The oscillator 10 to be generated, the amplifier 12 that amplifies the high-frequency signal generated by the oscillator 10, the distributor 14 that distributes the output of the amplifier 12 to the transmission signal Ss and the local signal L, and the radar wave corresponding to the transmission signal Ss And a receiving antenna unit 20 including n receiving antennas that receive radar waves.

  The radar sensor 3 sequentially selects one of the antennas constituting the reception antenna unit 20, and receives the reception signal Sr from the selected antenna to the subsequent stage, and the reception supplied from the reception switch 21. An amplifier 22 that amplifies the signal Sr, a mixer 23 that generates the beat signal BT by mixing the reception signal Sr and the local signal L amplified by the amplifier 22, and an unnecessary signal component from the beat signal BT generated by the mixer 23 Filter 24, A / D converter 25 that samples the output of filter 24 and converts it into digital data, and controls start and stop of oscillator 10 and sampling of beat signal BT via A / D converter 25. In addition, signal processing using the sampling data (generation of target information and diagnostic information) and inter-vehicle control It communicates with CU 30, and a signal processing unit 26 that performs processing such as transmitting and receiving information obtained as a result of the information and signal processing required for signal processing.

  In addition, each antenna which comprises the receiving antenna part 20 shall be allocated to receiving channel CH1-CHn, respectively. The signal processing unit 26 is configured around a known microcomputer including at least a CPU, a memory such as a ROM and a RAM (central axis recording unit, history recording unit), and further via an A / D converter 25. An arithmetic processing device (for example, a DSP) or the like is provided for executing fast Fourier transform (FFT) processing or the like on the captured data.

[Overview of radar sensor operation]
In the radar sensor 3 configured as described above, when the oscillator 10 is started in accordance with a command from the signal processing unit 26, the oscillator 10 generates a high frequency signal, and the amplifier 14 amplifies the high frequency signal amplified by the amplifier 12. Thus, the transmission signal Ss and the local signal L are generated, and the transmission signal Ss is transmitted as a radar wave through the transmission antenna 16.

  Then, the reflected wave transmitted from the transmitting antenna 16 and reflected back to the object is received by all the receiving antennas constituting the receiving antenna unit 20, and the receiving channel CHi (i = i = selected by the receiving switch 21). 1 to n) received signals Sr are amplified by the amplifier 22 and then supplied to the mixer 23.

  Then, the mixer 23 generates the beat signal BT by mixing the received signal Sr with the local signal L from the distributor 14. The beat signal BT is sampled by the A / D converter 25 after the unnecessary signal components are removed by the filter 24 and taken into the signal processing unit 26.

  The reception switch 21 is switched so that all reception channels CH1 to CHn are selected a predetermined number of times (for example, 512 times) during one modulation period of the radar wave composed of the upstream and downstream sections, The A / D converter 25 performs sampling in synchronization with this switching timing. In other words, sampling data is accumulated for each reception channel CH1 to CHn and for each up / down section of the radar wave during one modulation section of the radar wave.

  Then, as shown in FIG. 3, the signal processing unit 26 of the radar sensor 3 executes radar transmission for three modulation sections every preset measurement period (100 ms in the present embodiment), and the three modulations. Based on the sampling data obtained in each section, information necessary for generating target information is collected, and abnormality such as dirt on the receiving surface is determined. Note that the processing related to the generation of target information (that is, the processing for detecting the angle at which an obstacle is located with respect to the direction of the central axis and the distance to the obstacle based on the reflected wave) is the same as the known processing. Description is omitted (obstacle detection means).

[Axis deviation correction processing]
In the radar sensor 3 of the present embodiment, an axis deviation correction process for correcting the direction of the center axis of the sensor is performed. FIG. 4 is a flowchart showing an axis deviation correction process executed by the signal processing unit 26. This processing is based on the relative movement vector with respect to the obstacle, which is the reference position when detecting the position (particularly the azimuth) of the obstacle. This is a correction process.

  The axis deviation correction process can be realized as the same process as that described in Japanese Patent No. 3331882, Japanese Patent No. 3414267, etc., and therefore the explanation of the axis deviation correction process is simple. To do. Further, the processing of S120 to S140 corresponds to the deflection amount detection means in the present invention.

  The shaft misalignment correction process is started at every measurement cycle described above, and as shown in FIG. 4, first, the steering angle of the host vehicle is acquired from a steering sensor (not shown), and this steering angle travels linearly. It is determined whether it is less than a reference rudder angle that can be recognized as being (S110). If the steering angle of the host vehicle is equal to or greater than the reference steering angle (S110: NO), the host vehicle is turning and there is a possibility that an accurate amount of shaft misalignment cannot be detected.

  Further, if the steering angle of the host vehicle is less than the reference steering angle (S110: YES), it indicates that the host vehicle is running in a substantially straight line. In this case, a reception signal (reception signal for each of a plurality of reception channels) based on the reflected wave is acquired, and the axis deviation amount θ is calculated (S120: reception signal acquisition means).

  The axis deviation amount θ is obtained by detecting a relative movement vector of the host vehicle with respect to the obstacle and calculating an angle formed by the relative movement vector and the direction of the central axis recorded in a memory such as a RAM. That is, if the relative movement vector and the direction of the central axis coincide with each other, as shown in FIG. 5A, the axis deviation amount θ (the amount of deflection of the sensor axis) becomes 0, and the relative movement vector and the direction of the central axis If they do not match, a non-zero axis deviation amount θ is detected as shown in FIG.

  Then, correction for subtracting the steering angle θs of the host vehicle from the axis deviation amount θ is performed, and this value is set to θshift (S130). If the steering angle θs of the host vehicle can be ignored, S130 may be omitted.

  Subsequently, θshift obtained in the current process is corrected using θshift obtained in the previous process. For example, a weighted average of the values of each θshift is taken, and this value is set as a new θshift (S140).

  Then, θshift is recorded as a history in a memory such as a RAM (S150: deflection amount recording means), and a correction value for correcting the direction of the central axis in this processing is calculated (S160: correction amount calculation means). As this correction value, for example, a value obtained by dividing θshift by a constant α larger than 1 may be adopted, or a predetermined value corresponding to the magnitude of the value of θshift may be adopted. That is, this correction value is set to a value that approaches the value of θshift in a plurality of times, instead of setting it to 0 in one process.

  Subsequently, the direction of the central axis is corrected by the correction value, the corrected direction of the central axis is recorded in a memory such as a RAM (S170: recording control means), and the axis deviation correction process is terminated. In the next axial deviation correction process, the axial deviation amount θ and the like are calculated using the corrected direction of the central axis.

[Abnormality detection processing]
Next, processing for detecting an abnormality of the radar sensor 3 using the result of the axis deviation correction processing will be described with reference to FIG. FIG. 6 is a flowchart showing an abnormality detection process performed by the signal processing unit 26 in parallel with the axis deviation correction process.

  In the abnormality detection process, the processes in S210 to S230 correspond to the first abnormality determination means in the present invention, and the processes in S340 and S350 correspond to the second abnormality determination means in the present invention. Moreover, although the abnormality detection process is a process that is repeatedly performed, the repetition period may be the same period as the axis deviation correction process or a period longer than this.

  Here, the abnormality of the radar sensor 3 means that the reflected wave is reflected by some channels, such as when the sensor axis itself is displaced due to an impact caused by a collision, or when dirt or cracks occur on a part of the receiving surface. This indicates a state in which the reception is not performed normally.

  In the abnormality detection process, first, a history of θshift recorded in a memory such as a RAM is extracted (S210). Then, it is determined whether or not there is an abnormality in the inclination when the history is displayed as a graph (S220).

  FIG. 7 is a graph showing the history of θshift. When there is no abnormality in the radar sensor 3, θshift approaches 0 as time passes, as shown in FIG. This is because the direction of the central axis is corrected so that θshift approaches 0 with the passage of time in the above-described axis deviation correction processing.

  However, when there is an abnormality in the radar sensor 3, the absolute value of θshift increases with time as shown by the thick line in FIG. 7B, or as shown by the thick line in FIG. The absolute value of θshift changes extremely (over the reference rate of change) over time. Accordingly, in the process of S220, a previously assumed change pattern of θshift is recorded in a memory such as a ROM as a reference pattern, and the actually detected change pattern of θshift deviates from the reference pattern (for example, FIG. 7). When the deviation is 20% or more from the reference pattern indicated by the thin line in FIG.

  If there is an abnormality in the inclination (S220: YES), the axis deviation flag is set to ON in the memory such as RAM (S230: abnormality recording means, protection means), and the process proceeds to S240. Note that the memory such as the RAM in the present embodiment is configured to be erased when the vehicle power supply (for example, the ignition switch) is turned off, but when the axis deviation flag is turned on, for example, Back-up is performed in the nonvolatile memory, and information for specifying an abnormality such as history, flag, and diagnosis is not erased from the vehicle.

On the other hand, if there is no abnormality in the inclination (S220: NO), the process immediately proceeds to S240. Subsequently, in the process of S240, a deviation (difference) in received power received by each channel is calculated (S240: deviation calculating means). In this process, every time a reception signal is obtained from a plurality of reception channels, the maximum reception signal power value (reception power) among the reception channels is extracted as the maximum channel. The deviation of the power value is calculated.
Then, it is determined whether or not each received power deviation is abnormal (S250). Here, if there is a difference between the received power deviations by more than a reference value (for example, 20% of the received power of the maximum channel: candidate threshold), it is determined that there is an abnormality. If there is an abnormality in the deviation of each received power (S250: YES), it is determined whether or not the axis deviation flag is ON (S310).

  If the axis deviation flag is in an ON state (S310: YES), the abnormality detection threshold value, which is a reference value for whether or not an abnormality is output, is changed to a small value (S320: threshold value changing means), and the process of S330 is performed. Transition. In the process of S320, for example, the abnormality detection threshold value is set to about a half value. However, the threshold value may not be less than the lower limit value so that the threshold value does not become extremely small.

  If the axis deviation flag is OFF (S310: NO), the process immediately proceeds to S330, and an abnormality determination value that is a value for determining abnormality in a memory such as a RAM is incremented (S330: determination value). The counting means) compares the abnormality determination value with the abnormality detection threshold value (S340). If the abnormality determination value is equal to or greater than the abnormality detection threshold (S340: YES), the abnormality diagnosis is turned on (S350: abnormality output means), and the abnormality detection process is terminated. If the abnormality determination value is less than the abnormality detection threshold (S340: NO), the abnormality detection process is immediately terminated.

  Thus, when the abnormal diagnosis is turned on, for example, a backup is made in a non-volatile memory, and information for specifying the abnormality such as history, flag, and diagnosis is not erased from the vehicle, and this abnormal diagnosis ( The fact that there is an abnormality) is output to the inter-vehicle control ECU 30.

  By the way, if there is no abnormality in the deviation of each received power in the processing of S250 (S250: NO), the maximum value of each received power deviation is compared with the release value set to a value smaller than the reference value ( S410). If the maximum deviation of each received power is less than the release value (S410: YES), the abnormality determination value is reset (S420), the abnormality diagnosis is set to the OFF state (S430), and the abnormality detection process is terminated. If the maximum deviation of each received power is greater than or equal to the release value (S410: NO), the detection process is immediately terminated.

  In the present embodiment, the axis deviation flag once turned on is not turned off in the above processing. The axis deviation flag is subjected to another process when the radar sensor 3 is repaired or maintained. At this time, the adjustment completion flag indicating that the adjustment of the axis deviation is completed is turned on in a memory such as the RAM of the signal processing unit 26. When it becomes a state, it becomes an OFF state.

[Effects of this embodiment]
In the radar sensor 3 constituting the vehicle control system 1 described in detail above, the signal processing unit 26 acquires a reception signal based on the reflected wave, and records it in advance in a memory such as a RAM of the signal processing unit 26 from this reception signal. The angle at which the obstacle is located with respect to the direction of the center axis and the distance to the obstacle are repeatedly detected. Then, the signal processing unit 26 repeatedly detects a deflection amount that is an angle formed by the relative movement vector of the host vehicle with respect to the obstacle and the direction of the central axis, and sets the deflection amount to a plurality of times so that the deflection amount approaches zero. The correction amount for correcting separately is calculated repeatedly.

  Further, the signal processing unit 26 sets the new central axis direction obtained by correcting the central axis direction by the correction amount as the central axis direction used when detecting an obstacle, and the RAM of the signal processing unit 26. And the deflection amount is recorded as a history in a memory such as a RAM of the signal processing unit 26. Then, the signal processing unit 26 determines that the radar sensor 3 is abnormal when the deflection amount change pattern deviates from a preset reference pattern.

  That is, in the present invention, a deflection amount that is an angle formed by the relative movement vector of the host vehicle and the direction of the central axis obtained until the start of the current process is detected, and the central axis is adjusted so that this deflection amount approaches zero. Correct the direction. Then, using the corrected direction of the central axis, the deflection amount is detected again, and the direction of the central axis is corrected so that the deflection amount further approaches zero. By repeating such processing, the deflection amount is converged to zero in a stepwise manner.

  In such a configuration, when there is no abnormality in the radar sensor 3, it is expected that a deflection amount change pattern is obtained such that the deflection amount approaches 0 at a predetermined number of repetitions. On the other hand, when the radar sensor 3 has an abnormality such as dirt, it is considered that a change pattern of the deflection amount different from that when there is no abnormality is obtained. Therefore, the radar sensor 3 holds a change pattern expected to be obtained when there is no abnormality as a reference pattern, and the radar sensor 3 has an abnormality when the deflection amount change pattern deviates from the reference pattern. I am trying to judge.

  According to such a radar sensor 3, in a configuration in which the direction of the central axis is corrected so that the deflection amount gradually approaches zero, the deflection amount is recorded, and the change pattern is simply compared with the reference pattern. An abnormality of the sensor 3 can be detected. Therefore, the abnormality of the radar sensor 3 can be detected with a simple process.

In the radar sensor 3, the signal processing unit 26 determines that the deflection amount is abnormal when the deflection amount increases with time.
According to such a radar sensor 3, it can be determined that there is an abnormality when the amount of deflection that should approach 0 increases with time.

  Further, in the radar sensor 3, the signal processing unit 26 determines that it is abnormal when the corrected deflection amount or the parameter linked to the corrected deflection amount changes beyond a preset reference change rate.

  According to such a radar sensor 3, even if the deflection amount approaches 0 with the passage of time, if the change rate at this time exceeds the reference change rate and is abnormally large, it is determined to be abnormal. Can do.

  Further, in the radar sensor 3, the deflection amount history is configured to be deleted when the power of the radar sensor 3 is turned off, and the signal processing unit 26 is determined to be abnormal. At this time, the fact that there is an abnormality is recorded, and when the fact that there is an abnormality is recorded, the history is protected from being deleted.

According to such a radar sensor 3, since the history is not deleted when an abnormality occurs, the cause when the abnormality occurs can be easily clarified by the history.
In the radar sensor 3, the signal processing unit 26 acquires reception signals for each of the plurality of reception channels from the radar sensor 3 having a plurality of reception channels that receive reflected waves with different antenna elements, and receives the reception signals from the plurality of reception channels. Each time a received signal is obtained, the maximum received signal power value among the received channels is extracted as the maximum channel, and the deviation of the power value from the maximum channel is calculated for each received channel. The signal processing unit 26 increments the abnormality determination value if the deviation calculated by the signal processing unit 26 is greater than or equal to a preset candidate threshold among the reception channels, and the abnormality determination value is set in advance. When the value exceeds the set abnormality determination threshold, it is determined that the radar sensor 3 is abnormal.

According to such a radar sensor 3, even when a state in which the deviation of the received power is large continuously occurs, it can be determined that there is an abnormality.
Further, in the radar sensor 3, the signal processing unit 26 changes the abnormality determination threshold to a smaller value when it is determined that there is an abnormality due to the deflection amount change pattern deviating from the reference pattern.

  According to the radar sensor 3 as described above, when an abnormality is detected due to the deviation pattern of the deflection amount deviating from the reference pattern, the time required to determine an abnormality due to a large deviation in received power can be reduced. Can do.

In the radar sensor 3, when the signal processing unit 26 determines that there is an abnormality due to a large deviation in received power, the signal processing unit 26 outputs that there is an abnormality.
According to such a radar sensor 3, it can be output that there is an abnormality by the signal processing unit 26. At this time, if there is an abnormality due to the deviation pattern of the deflection amount deviating from the reference pattern, the cause of the abnormality can be easily identified by referring to the history.

Further, in the radar sensor 3, the signal processing unit 26 repeatedly detects a deflection amount obtained by adding a deflection amount detected in the past to the latest deflection amount.
According to such a radar sensor 3, since the deflection amount is detected in consideration of the deflection amount detected in the past, it is abnormal when the deflection amount temporarily changes greatly due to the influence of noise or vibration. Can be prevented from being erroneously detected.

[Other Embodiments]
Embodiments of the present invention are not limited to the above-described embodiments, and can take various forms as long as they belong to the technical scope of the present invention.

  For example, in the above-described embodiment, the shaft misalignment correction process is ended during turning, but if the amount of shaft misalignment can be accurately detected, the process of correcting the shaft misalignment may be continued. In the present embodiment, the present invention is applied to a millimeter wave radar. However, the present invention may be applied to an apparatus that detects an abnormality of a distance detection apparatus such as a laser radar or a sonar.

  In the above embodiment, whether or not there is an abnormality is determined based on the change pattern of the deflection amount itself, but a parameter linked to the deflection amount may be used instead of the deflection amount itself.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle control system, 3 ... Radar sensor, 3a ... Housing, 3b ... Antenna board, 3c ... Radome, 10 ... Oscillator, 12 ... Amplifier, 14 ... Distributor, 16 ... Transmission antenna, 20 ... Reception antenna part, 21 DESCRIPTION OF SYMBOLS ... Reception switch, 22 ... Amplifier, 23 ... Mixer, 24 ... Filter, 25 ... A / D converter, 26 ... Signal processing part, 30 ... Inter-vehicle control ECU, 32 ... Engine ECU, 34 ... Brake ECU.

Claims (9)

An abnormality detection device that detects an abnormality of an obstacle detection device that is mounted on a vehicle, irradiates a predetermined transmission wave within a predetermined angle range in the vehicle width direction, and detects an obstacle based on the reflected wave,
Received signal acquisition means for acquiring a received signal based on the reflected wave;
Obstacle detection means for repeatedly detecting an angle at which the obstacle is located with respect to the direction of the central axis recorded in advance in the central axis recording unit from the received signal and a distance to the obstacle;
A deflection amount detecting means for repeatedly detecting a deflection amount that is an angle formed by a relative movement vector of the host vehicle with respect to the obstacle and a direction of the central axis;
Correction amount calculation means for repeatedly calculating a correction amount when correcting the deflection amount in a plurality of times so that the deflection amount approaches 0;
In the central axis recording unit, a new central axis direction obtained by correcting the central axis direction by the correction amount is used as the central axis direction used when the obstacle detecting means detects the obstacle. Recording control means for recording;
A deflection amount recording means for recording the deflection amount or a parameter linked to the deflection amount as a history in a history recording unit;
First abnormality determining means for determining that there is an abnormality in the obstacle detection device when the deflection amount or a parameter change pattern linked to the deflection amount deviates from a preset reference pattern;
An abnormality detection device characterized by comprising: The abnormality detection device according to claim 1,
The abnormality detection device according to claim 1, wherein the first abnormality determination means determines that an abnormality occurs when the deflection amount or the parameter linked to the deflection amount increases with time. In the abnormality detection device according to claim 1 or 2,
The first abnormality determining means determines that an abnormality is present when the corrected deflection amount or a parameter linked to the corrected deflection amount changes beyond a preset reference change rate. Anomaly detection device. In the abnormality detection apparatus according to any one of claims 1 to 3,
The history is configured to be deleted when the abnormality detection device is turned off.
An abnormality recording means for recording that there is an abnormality when the first abnormality determining means determines that there is an abnormality;
Protecting means for protecting the history and the fact that there is an abnormality from being deleted when it is recorded that there is an abnormality,
An abnormality detection device characterized by comprising: In the abnormality detection device according to any one of claims 1 to 4,
The reception signal acquisition means acquires a reception signal for each of the plurality of reception channels from an obstacle detection device having a plurality of reception channels that receive the reflected waves by mutually different antenna elements,
The abnormality detection device is
Each time a reception signal is obtained from the plurality of reception channels, the reception channel having the maximum power value of the reception signal is extracted as the maximum channel, and the power value with the maximum channel is determined for each reception channel. Deviation calculating means for calculating the deviation of
A determination value counting means for incrementing an abnormality determination value if any of the reception channels has a deviation calculated by the deviation calculation means equal to or greater than a preset candidate threshold;
Second abnormality determination means for determining that the obstacle detection device has an abnormality when the abnormality determination value is equal to or greater than a predetermined abnormality determination threshold;
An abnormality detection device comprising: In the abnormality detection device according to claim 5,
An abnormality detection apparatus comprising: a threshold value changing unit that changes the abnormality determination threshold value to a smaller value when the first abnormality determination unit determines that there is an abnormality. In the abnormality detection device according to claim 5 or 6,
An abnormality detection device, comprising: an abnormality output means for outputting that there is an abnormality when the second abnormality determination means determines that there is an abnormality. In the abnormality detection device according to any one of claims 1 to 7,
The abnormality detection device, wherein the deflection amount detection means repeatedly detects a deflection amount in which a deflection amount detected in the past is added to the latest deflection amount.   The abnormality detection program for functioning a computer as each means which comprises the abnormality detection apparatus of any one of Claims 1-8.