JP7708060B2 - Abnormal Sound Diagnostic System - Google Patents

Description

This disclosure relates to an abnormal sound diagnosis system that diagnoses abnormal sounds generated in a vehicle.

Conventionally, a hybrid vehicle including a transmission mechanism having a gear train to which an engine, a first rotating electric machine, and a second rotating electric machine are connected is known (see, for example, Patent Document 1). A control device of this hybrid vehicle determines whether or not an abnormal sound generation condition of the gear train is satisfied, and controls the first rotating electric machine to apply a pressing torque to the gear train when a dwell time, which is a period during which the abnormal sound generation condition is continuously satisfied, exceeds a predetermined value. In addition, the control device prevents a pressing torque from being applied to the gear train when the abnormal sound generation condition is not satisfied and when the dwell time is within a predetermined value. In this way, in the hybrid vehicle, it is possible to suppress the generation of abnormal sounds in the gear train that are strange to the user, while suppressing movement of the crank angle that may cause a shock when the engine is started.

JP 2016-222090 A

When an abnormal sound occurs that should be reduced by the abnormal sound reduction control (application of pushing torque) executed on the vehicle, such as the above-mentioned teeth rattle, a variety of sounds are generated in the vehicle, so it is not easy to determine whether the actually recognized abnormal sound is one that should be reduced by the abnormal sound reduction control based on hearing or the vehicle state at the time the abnormal sound occurs.

Therefore, the primary objective of this disclosure is to make it possible to accurately determine whether or not an abnormal noise generated in a vehicle should be reduced by abnormal noise reduction control executed in the vehicle.

The abnormal sound diagnosis system disclosed herein is an abnormal sound diagnosis system that includes a terminal that acquires data on sounds emitted from a vehicle and medical interview information related to abnormal sounds generated in the vehicle, and an information processing device that diagnoses the abnormal sound generated in the vehicle based on the sound data and the medical interview information from the terminal, and when the information processing device diagnoses that the abnormal sound generated in the vehicle should be reduced by abnormal sound reduction control executed in the vehicle, the terminal is capable of displaying on a display unit the change in the control signal of the abnormal sound reduction control and the change in the sound data acquired in synchronization with the output of the control signal.

In the abnormal sound diagnosis system of the present disclosure, when the information processing device diagnoses that an abnormal sound generated in a vehicle should be reduced by abnormal sound reduction control executed in the vehicle, the terminal displays on the display unit the change in the control signal for the abnormal sound reduction control and the change in the sound data acquired in synchronization with the output of the control signal. This allows the user of the abnormal sound diagnosis system to accurately determine whether or not an abnormal sound generated in the vehicle should be reduced by abnormal sound reduction control, based on the change in the sound data in response to the change in the control signal displayed on the display unit.

The vehicle may also include an electric motor, and the abnormal noise reduction control may cause the electric motor to output torque to suppress the generation of the abnormal noise.

Furthermore, the vehicle may include an engine and a power transmission mechanism having a plurality of gears and connected to the engine and the electric motor, the abnormal noise may be a gear rattle generated in the power transmission mechanism, and the abnormal noise reduction control may cause the electric motor to intermittently output a pressing torque to eliminate backlash between the gears.

In this manner, by checking the change in sound data on the display unit when no pressing torque is output from the electric motor, it becomes possible to accurately determine whether or not an abnormal sound generated in the vehicle should be reduced by the abnormal sound reduction control executed in the vehicle.

The terminal may also be a mobile terminal that includes the display unit, a sound acquisition unit that acquires the sound data, and a medical interview information acquisition unit that acquires the medical interview information, and that communicates with the information processing device to exchange information.

This makes it easier to obtain sound data, reduces the load on the mobile device, and enables more accurate diagnostic results to be obtained from the diagnostic device.

Furthermore, the information processing device may include a diagnosis unit constructed by machine learning to diagnose the cause of the abnormal sound based on given information.

1 is a schematic configuration diagram showing an abnormal sound diagnosis system according to the present disclosure. 4 is a flowchart showing a series of processes executed by an information processing device constituting the abnormal sound diagnosis system of the present disclosure. FIG. 11 is an explanatory diagram illustrating an example of an abnormal sound diagnosis result displayed on a display unit of a terminal constituting the abnormal sound diagnosis system of the present disclosure.

Next, the form for implementing the invention of this disclosure will be described with reference to the drawings.

Figure 1 is a schematic diagram showing an abnormal sound diagnosis system 1 of the present disclosure. The abnormal sound diagnosis system 1 shown in the figure is for diagnosing the cause of abnormal sounds generated in a vehicle V, which may be a vehicle equipped with only an engine as a power generation source, an electric vehicle (BEV, FCEV), or a hybrid vehicle (HEV, PHEV) as shown in Figure 1. The vehicle V includes an engine (internal combustion engine) EG, motor generators MG1, MG2, and a power transmission mechanism TM including a planetary gear PG for power distribution, a counter drive gear Ga, a counter driven gear Gb, and a final drive gear (drive pinion gear) Gc.

The planetary gear PG of the vehicle V is a differential rotation mechanism including a sun gear Ps, a ring gear Pr, and a planetary carrier Pc that rotatably supports multiple pinion gears Pp. As shown in FIG. 1, the sun gear Ps is connected to the rotor of the motor generator MG1, and the planetary carrier Pc is connected to the crankshaft of the engine EG via a damper mechanism DD. The ring gear Pr rotates coaxially and integrally with the counter drive gear Ga (output member) of the power transmission mechanism TM. Furthermore, the final drive gear Gc of the power transmission mechanism TM meshes with the differential ring gear Dr of the differential gear DF, and is connected to the left and right wheels (drive wheels) via the differential gear DF and the drive shaft DS.

In such a vehicle V, when the engine EG is idled (operated independently) so as not to substantially output torque, there is a risk that the input gear teeth of the power transmission mechanism TM will hit the output gear teeth due to rotational fluctuations of the engine EG, causing teeth rattle noise. For this reason, in the vehicle V, when the engine EG is idled, a pressing control is executed as an abnormal noise reduction control, in which a pressing torque is intermittently output to the motor generator MG1 to eliminate backlash between the meshing gears of the power transmission mechanism TM.

As shown in FIG. 1, the abnormal sound diagnosis system 1 includes a mobile terminal 10 and a server 20 as an information processing device capable of exchanging information with the mobile terminal 10 by communication. The mobile terminal 10 is used by a worker (user of the abnormal sound diagnosis system 1) at a vehicle dealership or repair shop to respond to a user (owner) of a vehicle V in which an abnormal sound has occurred, or to perform a reproduction test in which the vehicle V is driven (operated) on a roadway or test bench to reproduce the abnormal sound. In this embodiment, the mobile terminal 10 is a smartphone including a SoC, a ROM, a RAM, an auxiliary storage device (flash memory) M, a touch panel display unit 11, a communication module 12 capable of exchanging various information with an electronic control unit (ECU) (not shown) of the server 20 or the vehicle V via wired or wireless communication, a microphone (not shown), etc. In addition, an abnormal sound diagnosis support application (program) is installed in the mobile terminal 10. As shown in FIG. 1, the mobile terminal 10 includes a medical interview information acquisition unit 13, a sound acquisition unit 14, a vehicle state acquisition unit 15, a calculation processing unit 16, an extraction unit 17, and a display control unit 18, which are constructed in cooperation with an abnormal sound diagnosis support application (software) and hardware such as the SoC of the mobile terminal 10.

The medical interview information acquisition unit 13 acquires information indicating the state of the vehicle V, etc., at the time of the occurrence of the abnormal sound, provided by the user of the vehicle V, etc., via the display unit 11 (hereinafter referred to as "medical interview information"). The medical interview information includes vehicle identification information including the vehicle model, vehicle identification number (chassis number), etc., orders, occurrence date and time, occurrence frequency, location of the abnormal sound, type of sound (onomatopoeia), physical quantities that change during the running of the vehicle V, etc., such as vehicle speed, the driving state of the vehicle V, etc., warm-up effects in an engine-equipped vehicle, selection items selected by the driver while driving the vehicle V, etc., driving environment information of the vehicle V, etc., and is input by the above-mentioned worker or the user of the vehicle V, etc. The sound acquisition unit 14 acquires time axis data of the sound (sound pressure) when the reproduction test is performed by the worker. The vehicle state acquisition unit 15 acquires information indicating the state of the vehicle V, etc. (hereinafter referred to as "vehicle state data") in synchronization with the acquisition of the time axis data of the sound by the sound acquisition unit 14 when the reproduction test is performed. The vehicle condition data includes multiple physical quantities (vehicle speed, engine speed, etc.) corresponding to the items of the medical interview information. The calculation processing unit 16 performs analysis processing of the time axis data of the sound acquired by the sound acquisition unit 14. The extraction unit 17 performs narrowing down of the analysis results by the calculation processing unit 16 according to the selection of the operator, etc. The display control unit 18 controls the display unit 11.

The server 20 as an abnormal sound diagnosis device is a computer (information processing device) including a CPU, ROM, RAM, input/output devices, a communication module, etc., and is installed and managed by, for example, an automobile manufacturer that manufactures the vehicle V. The server 20 is configured with an abnormal sound diagnosis unit 21 that diagnoses abnormal sounds generated in the vehicle V, etc., through cooperation between hardware such as a CPU and a pre-installed abnormal sound diagnosis application. The abnormal sound diagnosis unit 21 includes a neural network (convolutional neural network) constructed by supervised learning (machine learning) to diagnose the cause of the abnormal sound generated in the vehicle V, etc., and the parts that are the source of the abnormal sound, based on the interview information and sound time axis data acquired by the mobile terminal 10. In addition, when the server 20 finds that a new abnormal sound has occurred in the vehicle V, etc., re-learning is performed for the abnormal sound diagnosis unit 21 using the sound time axis data acquired for the new abnormal sound and the contents of each item of the interview information, etc., as teacher data.

Furthermore, the server 20 includes a storage device 22 that stores an abnormal sound database that stores information on a plurality of abnormal sounds that are known to occur in the vehicle for each vehicle model. The abnormal sound database stores information such as time axis data of the sound, the cause of the abnormal sound, the part that is the source of the abnormal sound, the contents of the medical interview information provided by the user, etc., and measures to eliminate the abnormal sound, for each of a plurality of abnormal sounds. In addition, the server 20 updates the abnormal sound database based on information acquired from a large number of vehicles including the vehicle V, and information (reports) on newly discovered abnormal sounds transmitted from automobile manufacturers (developers, etc.), vehicle dealers, maintenance shops, etc. Note that, as a technique for constructing the abnormal sound diagnosis unit 21, for example, those described in the following papers (1) to (5) or a combination thereof can be used.
(1) Unsupervised Filterbank Learning Using Convolutional Restricted Boltzmann Machine for Environmental Sound Classification
(2) LEARNING FROM BETWEEN-CLASS EXAMPLES FOR DEEP SOUND RECOGNITION
(3) Novel Phase Encoded Mel Filterbank Energies for Environmental Sound Classification
(4) Knowledge Transfer from Weakly Labeled Audio using Convolutional Neural Network for Sound Events and Scenes
(5) Novel TEO-based Gammatone Features for Environmental Sound Classification

Next, the procedure for diagnosing abnormal sounds generated in the vehicle V using the abnormal sound diagnosis system 1 will be described with reference to Figures 2 and 3.

When a worker at a vehicle dealership or repair shop is requested by a user of a vehicle V to eliminate an abnormal sound, the worker listens to the user's medical history and then performs a reproduction test to obtain information necessary for diagnosing the abnormal sound. When performing the reproduction test, the worker connects the mobile terminal 10 to the electronic control device of the vehicle V, and places or fixes the mobile terminal 10 or an external microphone connected to the mobile terminal 10 in an appropriate position on the vehicle V. The worker also starts an abnormal sound diagnosis support application and turns on the start switch of the vehicle V. Accordingly, the mobile terminal 10 obtains information such as the vehicle identification number or chassis number of the vehicle V from the electronic control device. Furthermore, the worker taps the recording start button displayed on the display unit 11 and drives (operates) the vehicle V on a roadway or a test stand to reproduce the driving condition in which the abnormal sound occurred based on the medical history from the user of the vehicle V.

While the vehicle V is running (operating), the sound acquisition unit 14 of the mobile terminal 10 acquires time axis data of the sound emitted from the vehicle V at predetermined time intervals (micro time) and stores it in the auxiliary storage device M, and the vehicle state acquisition unit 15 acquires vehicle state data specified by the operator in response to medical interview information from the user of the vehicle V, etc., from the electronic control device of the vehicle V at predetermined time intervals (micro time) in synchronization with the acquisition of the sound time axis data by the sound acquisition unit 14, and stores it in the auxiliary storage device M. When the operator taps the recording stop button displayed on the display unit 11, the acquisition of the sound time axis data and vehicle state data is completed.

After the reproduction test is completed, the calculation processing unit 16 performs STFT (Short-Time Fourier Transform) on the time axis data of the sound to obtain a spectrogram (acoustic spectrogram) showing the relationship between time, frequency, and sound pressure, and the display control unit 18 displays the spectrogram on the display unit 11. In this embodiment, the spectrogram is a color map in which the horizontal axis is the time axis and the vertical axis is the frequency axis, and the sound pressure level is color-coded to show the relationship between time and sound pressure level for each frequency. In addition, the operator selects (specifies) on the display unit 11 the range (hereinafter referred to as the "diagnosis range") of the spectrogram to be diagnosed (analyzed) by the abnormal sound diagnosis unit 21 (server 20). Furthermore, the operator inputs the interview information into the input screen displayed on the display unit 11. Then, when the operator taps the information transmission button displayed on the display unit 11, the information necessary for diagnosing the abnormal sound is transmitted from the communication module 12 of the mobile terminal 10 to the server 20. In this embodiment, the information transmitted from the mobile terminal 10 to the server 20 includes time axis data of the sound acquired by the sound acquisition unit 14, vehicle condition data acquired by the vehicle condition acquisition unit 15, medical interview information, and information defining the diagnostic range selected by the operator.

Figure 2 is a flowchart showing a series of processes executed by the abnormal sound diagnosis unit 21 of the server 20 in response to receiving information from the mobile device 10.

As shown in FIG. 2, the abnormal sound diagnosis unit 21 of the server 20 acquires the sound time axis data, vehicle condition data, medical interview information, and information defining the diagnosis range from the mobile terminal 10 (step S100), and diagnoses the cause of the abnormal sound generated in the vehicle V using the neural network based on this information (step S110). The diagnosis result obtained in step S110 includes the abnormal sound name, the part that is the source of the abnormal sound, etc. Furthermore, based on the abnormal sound name etc. obtained in step S110, the abnormal sound diagnosis unit 21 determines whether the abnormal sound generated in the vehicle V should be reduced by the abnormal sound reduction control executed in the vehicle V (step S120).

If it is determined that the abnormal sound generated in the vehicle V should be reduced by the abnormal sound reduction control (step S120: YES), the abnormal sound diagnosis unit 21 obtains information on the abnormal sound reduction control corresponding to the abnormal sound and sample abnormal sound data (time axis data) when the abnormal sound occurred from the storage device 22 (step S130). For example, if the abnormal sound name obtained in step S110 is "gear rattle during engine EG idling operation" that is reduced by the above-mentioned pressing control, in step S130, the abnormal sound diagnosis unit 21 obtains from the storage device 22 information that the abnormal sound reduction control is pressing control and sample abnormal sound data when the gear rattle occurs during engine EG idling operation. Also, if it is determined that the abnormal sound generated in the vehicle V should not be reduced by the abnormal sound reduction control (step S120: NO), the processing of step S130 is skipped.

After the process of step S120 or S130, the abnormal sound diagnosis unit 21 creates a final diagnosis result based on the diagnosis result in step S110 (step S140). The final diagnosis result by the abnormal sound diagnosis unit 21 includes the abnormal sound name, the part that is the source of the abnormal sound, the cause of the abnormal sound, and measures to eliminate the abnormal sound read from the storage device 22. Furthermore, when the process of step S130 is executed, the final diagnosis result by the abnormal sound diagnosis unit 21 includes information on abnormal sound reduction information (for example, a recommendation for verification by executing the above-mentioned pressing control and the procedure for doing so) and sample abnormal sound data. Furthermore, the abnormal sound diagnosis unit 21 transmits the result created in step S160 to the mobile terminal 10, and ends the series of processes in FIG. 2.

When the diagnostic result from the server 20 is received by the mobile terminal 10, the diagnostic result is displayed on the display unit 11. This allows the worker to accurately explain the diagnostic result from the server 20 to the user of the vehicle V and quickly proceed with measures against the abnormal sound. For example, if the abnormal sound diagnosis unit 21 of the server 20 diagnoses that the abnormal sound generated in the vehicle V is a rattle sound during idling, the worker can verify the diagnosis result by the server 20 by playing back the sample abnormal sound data from the server 20 and the time axis data of the sound obtained in the previous reproduction test on the mobile terminal 10 and comparing the two, or by comparing the sample abnormal sound data with the sound actually emitted from the vehicle V. Furthermore, if the abnormal sound diagnosis unit 21 of the server 20 diagnoses that the abnormal sound generated in the vehicle V should be reduced by abnormal sound reduction control, the worker can verify the diagnosis result by the server 20 according to the information on abnormal sound reduction control included in the diagnosis result from the server 20.

When verifying the diagnostic results by the server 20, the worker connects a terminal such as a personal computer (a terminal different from the mobile terminal 10) on which a separately prepared diagnostic work tool is installed to the electronic control device of the vehicle V via a cable (dongle). The diagnostic work tool is capable of outputting a control signal for noise reduction control such as pressing control from outside to the vehicle V with the execution of the noise reduction device by the electronic control device of the vehicle V disabled. The worker also connects the mobile terminal 10 to the terminal via short-range wireless communication or a cable, and fixes an external microphone connected to the mobile terminal 10 to the engine compartment of the vehicle V or the like. The worker then turns on the start switch of the vehicle V and performs a reproduction test using the diagnostic work tool and the mobile terminal 10.

When the server 20 diagnoses that rattle noise occurs during engine EG idling in the vehicle V, the reproduction test involves outputting a control signal from the diagnostic work tool while the engine EG is idling, causing the motor generator MG1 to output the above-mentioned pressing torque. In addition, while the reproduction test is being performed, a signal indicating the output state of the control signal (output state of the pressing torque) is transmitted from the diagnostic work tool to the communication module 12 of the mobile terminal 10, and the sound acquisition unit 14 of the mobile terminal 10 acquires time axis data of the sound from the external microphone in synchronization with the output of the control signal from the diagnostic work tool. Then, as shown in FIG. 5, the display control unit 18 displays the signal waveform (changing mode) of the control signal for the abnormal sound reduction control and the sound pressure waveform (changing mode) of the time axis data of the sound acquired by the sound acquisition unit 14 on the display unit 11 with the time axes aligned.

This allows the operator (user of the abnormal sound diagnosis system 1) to accurately determine whether an abnormal sound generated in the vehicle V (e.g., a gear rattle during idling) is a gear rattle that should be reduced by the abnormal sound reduction control (e.g., a pressing control) from the change in sound pressure (time axis data of sound) in response to a change in the control signal of the abnormal sound reduction control displayed on the display unit 11. That is, when the server 20 diagnoses that a gear rattle is generated during idling of the engine EG in the vehicle V, the pressing control as the abnormal sound reduction control is to intermittently output a pressing torque to the motor generator MG1 to eliminate backlash between the gears, as shown in FIG. 3. Therefore, by checking the change in sound pressure when the pressing torque is not output from the motor generator MG1 on the display unit 11, it becomes possible to accurately determine whether an abnormal sound generated in the vehicle V is a gear rattle that should be reduced by the pressing control executed in the vehicle V. In the example shown in FIG. 3, the sound pressure (amplitude) is large when no pushing torque is output from the motor generator MG1, so it is determined that some abnormality is causing rattle noise during engine EG idling, even when pushing torque is being applied.

The abnormal sound diagnosis system 1 also includes a display unit 11, a medical interview information acquisition unit 13 that acquires medical interview information, and a sound acquisition unit 14 that acquires sound time axis data, as well as a mobile terminal 10 that exchanges information with a server 20 through communication. This makes it possible to easily acquire sound time axis data and reduce the load on the mobile terminal 10, thereby enabling more accurate diagnosis results to be obtained from the server 20. However, the abnormal sound diagnosis support application installed on the mobile terminal 10 may also be installed on a tablet terminal, a laptop or desktop personal computer, or the like, and the tablet terminal or the like may be used instead of the mobile terminal 10. The abnormal sound diagnosis system 1 may also be configured as a single information processing device such as a personal computer.

Furthermore, the abnormal noise to be judged in step S120 of FIG. 2 is not limited to the rattle noise during idling of the engine EG that should be reduced by the pressing control, but may be, for example, an abnormal noise generated by the variable valve timing mechanism of the engine, as long as it can be reduced by a predetermined abnormal noise reduction control. Furthermore, the abnormal noise reduction control is not limited to the output of torque from the motor generator MG1, etc., but may be, for example, the adjustment of the opening of an electronically controlled throttle valve. Therefore, the verification of the diagnosis result of the server 20 by comparing the signal waveform (changing state) of the control signal of the abnormal noise reduction control with the sound pressure waveform of the time axis data of the sound can be performed not only in the vehicle V including the engine, the motor generators MG1 and MG2, and the power transmission mechanism TM, but also in a one-motor hybrid vehicle including the engine, the motor generator, and the transmission, a vehicle equipped with only an engine as a power source, and an electric vehicle.

In addition, when a reproduction test is performed in response to the diagnosis result from the server 20, instead of using the above-mentioned diagnostic work tool, the mobile terminal 10 may request the server 20 to transmit a control signal for the abnormal sound reduction control, and the control signal transmitted from the server 20 to the in-vehicle communication device may operate the control target of the abnormal sound reduction control. Furthermore, the above-mentioned diagnostic work tool may be installed in the mobile terminal 10, in which case a control signal may be output from the mobile terminal 10 to operate the control target of the abnormal sound reduction control.

The invention disclosed herein is in no way limited to the above embodiment, and it goes without saying that various modifications can be made within the scope of the present disclosure. Furthermore, the above embodiment is merely one specific form of the invention described in the Summary of the Invention section, and does not limit the elements of the invention described in the Summary of the Invention section.

The disclosed invention is extremely useful for diagnosing abnormal noises occurring in vehicles.

1 Abnormal sound diagnosis system, 10 Mobile terminal, 11 Display unit, 12 Communication module, 13 Questionnaire information acquisition unit, 14 Sound acquisition unit, 15 Vehicle state acquisition unit, 16 Calculation processing unit, 17 Extraction unit, 18 Display control unit, 20 Server (information processing device), 21 Abnormal sound diagnosis unit, 22 Storage device, Ga Counter drive gear, Gb Counter driven gear, Gc Final drive gear, MG1, MG2 Motor generator, PG Planetary gear, TM Power transmission mechanism, V Vehicle.

Claims (5)

An abnormal sound diagnosis system including: a terminal that acquires data of a sound emitted from a vehicle and inquiry information regarding an abnormal sound generated in the vehicle; and an information processing device that diagnoses the abnormal sound generated in the vehicle based on the sound data and the inquiry information from the terminal,
The abnormal sound diagnosis system is capable of displaying on a display unit, when the information processing device diagnoses that the abnormal sound generated in the vehicle is one that should be reduced by abnormal sound reduction control executed in the vehicle, the change in the control signal of the abnormal sound reduction control and the change in the sound data acquired in synchronization with the output of the control signal. The abnormal sound diagnosis system according to claim 1,
The abnormal noise diagnosis system wherein the vehicle includes an electric motor, and the abnormal noise reduction control causes the electric motor to output a torque for suppressing the generation of the abnormal noise. The abnormal sound diagnosis system according to claim 2,
The vehicle includes an engine and a power transmission mechanism having a plurality of gears and connected to the engine and the electric motor,
the abnormal noise is a gear rattle generated in the power transmission mechanism,
The abnormal noise reduction control is an abnormal noise diagnosis system that causes the electric motor to intermittently output a pressing torque to eliminate backlash between the gears. The abnormal sound diagnosis system according to any one of claims 1 to 3,
The terminal is a portable terminal that includes the display unit, a sound acquisition unit that acquires the sound data, and a medical interview information acquisition unit that acquires the medical interview information, and that communicates with the information processing device to exchange information. The abnormal sound diagnosis system according to any one of claims 1 to 3,
The information processing device is an abnormal sound diagnosis system including a diagnosis unit constructed by machine learning so as to diagnose the cause of the abnormal sound based on given information.