Patent Publication Number: US-2021163032-A1

Title: Device control apparatus, and control method for controlling devices

Description:
TECHNICAL FIELD 
     The present invention relates to device control apparatus and control methods for device. 
     BACKGROUND OF THE INVENTION 
     Conventionally known, the voice recognition result notification method of the onboard electronic device recognizes the voice emitted by the user by the voice recognition means, and outputs a synthetic voice as a message from the speaker in accordance with the recognition result, when receiving the notification instruction again from the user, and outputs the synthetic voice from the speak er again performs notification. Then, when a predetermined time that can accept the re-notification instruction has elapsed, a predetermined process is performed based on the recognition result (e.g., Patent Document 1). 
     CITAION LIST 
     Patent Document 
     
         
         [Patent Document 1] JP 2003-271193A 
       
    
     SUMMARY OF THE INVENTION 
     Problem to be Solved by the Invention 
     However, in the above notification method, there is a problem that it takes a lot of time until the device executes a predetermined process after the user utters a voice. 
     The problem to be solved by the invention is to provide a device control apparatus and a control method for controlling device which can shorten the time from when the user speaks to when the device operates. 
     Means for Solving Problem 
     The present invention recognizes the voice of the user and identifies the type of the operation target device to be operated from among the plurality of devices and the operation content of the operation target device based on the recognized voice and controls timing of activating the operation target device with identified operation content according to the type of identified operation target, thereby, the above problems can be solved. 
     Effect of the Invention 
     The present invention can shorten the time from when the user speaks to when the device operates. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of a device control apparatus. 
         FIG. 2  is a block diagram of the controller shown in  FIG. 1 .  FIG. 3  is a flowchart showing a control flow of the controller shown in  FIG. 1 . 
     
    
    
     MODE(S) FOR CARRYING OUT THE INVENTION 
     Hereinafter, embodiments of the present invention will be described with reference to the drawings. 
     First Embodiment 
       FIG. 1  is a block diagram of a device control apparatus  1  according to the present invention. Device control apparatus  1  includes a microphone  11 , a speaker  12 , a wiper  21 , a light  22 , an audio  23 , an air conditioner  24 , a data base  30 , and a controller  100 . Device control apparatus  1  of the present embodiment is a control device to be mounted on a vehicle, recognizes the voice of the user based on the voice, and controls a plurality of on-board devices. 
     The microphone  11  converts the voice emitted by the user into an electrical signal and outputs it to the controller  100 . The microphone  11  corresponds to a detector that detects sound in the cabin, including the user&#39;s voice. Speaker  12  is a device for converting the audio signal output from the controller  100  into sound and emitting a sound toward the user in the vehicle cabin. The voice recognition system includes a microphone  11 , a speaker  12 , a database  30 , and a controller  100 . The voice recognition system utilizes known voice recognition techniques to identify information representing a user&#39;s intention from sounds detected by microphone  11 . The voice recognition system, in response to identified information, emits a sound from the speaker  12 . Thus, the voice recognition system realizes the dialogue between the user and the controller  100 . 
     The wiper  21  is a device for removing dirt on the surface of the windshield. The light  22  is a lighting apparatus for illuminating the exterior of the vehicle. The audio is a device including a radio and a reproduction device, a device for playing music in the vehicle cabin. The air conditioner  24  is an apparatus for adjusting the air conditioning (temperature, etc.) in the vehicle interior. The wiper  21  and the light  22  are device related to driving (hereinafter referred to as driving-related device). The driving-related device is device that affects the behavior of the vehicle and/or the driving operation of the user when the vehicle is driven by user operation or automatic driving. Incidentally, the driving-related device is not limited to the wiper  21  and the light  22 , for example, a handle, a winker. 
     The audio  23  and the air conditioner  24  is device not related to driving (hereinafter, also referred to as non-driving-related device). Non-driving-related device is not limited to the audio  23  and the air conditioner  24 , may be, for example, a reading light. 
     The database  30  is a recording medium, such as data required for voice recognition and data necessary for operation of the onboard device are recorded. Data necessary for voice recognition includes data of acoustic models necessary to distinguish words such as “a”, “i” when it is Japanese. Also, algorithms are stored in the data required for voice recognition to emphasize the similarity between the recognized voice signal and a specific sequence. In addition, data for identifying device to be operated (hereinafter, also referred to as device identification data) and data for identifying the operation of certain device (also referred to as operation identification data) are recorded in the database. For example, the identification data for identifying the air conditioner  24  includes data of the name “e-a-ko-n” and data of the name “re-i-bo” (both are Japanese name of air conditioner). Operation identification data is stored in a database after distinguishing which of two types, at least, driving-related device and non-driving-related device, corresponds to. For example, when the operation identification data is an air conditioner, it falls into the type of non-driving-related device. 
     The operation identification data is data representing various operations of the device, classified for each device, and stored in the database  30 . For example, when the device is an air conditioner  24 , the operation identification data indicates the name of the operation required to operate the air conditioner  24 , the number, and a term indicating the temperature adjustment. For example, when the user utter a voice to activate the air conditioner, it is anticipated that the user will utter terms such as “on”, “off”, “intensify”, “weaken”, “dry mode”, “ 25 ° C.”. The operation identification data includes such language data on the operation. A plurality of operation identification data relating to the air conditioner  24  is associated with the device identification data of the air conditioner  24  and is recorded in the database  30 . 
     The database  30  also stores the data of the recognition result by the voice recognition system. For example, when the user performs a dialogue with the controller  100 , the data recognized from the voice of the user is recorded in the database  30 . The voice data of the user recorded in the database  30  is analyzed and the keyword used for the above-described voice recognition process is updated so that the accuracy of the voice recognition is improved. 
     The controller  100  controls devices such as wipers  21 , lights,  22 , audio  23  and air conditioner  24 , and voice recognition systems. The controller  100  has a ROM, a CPU. The ROM has the program for controlling such devices and systems. The CPU is a unit for executing the program recorded in the ROM. The controller  100  is a control body for executing the control method of the apparatus of the present embodiment. 
     Next, with reference to  FIG. 2 , the function of the controller  100 . FIG.  2  is a block diagram of the controller  100 . The controller  100  includes a voice input/output unit  101 , a voice recognition unit  102 , a device identifying unit  103 , and an operation command unit  104  as a functional block for controlling devices using a voice recognition system. 
     The voice input/output unit  101  uses the microphone  11  to acquire the voice data of the voice uttered by the user and transmits the voice data to the voice recognition unit  102  at a predetermined cycle. The voice input/output unit  101  uses the speaker  12  to output the data of the sound generated by the voice recognition unit  102  to the user. The voice input/output unit  101  waits in a state in which the voice from the user can be acquired during operation of an apparatus such as an air conditioner  24 . In addition, the voice input/output unit  101  waits in a state in which the voice from the user can be acquired even during a dialogue. The dialogue is between the user and the controller  100  utilizing a voice recognition system. 
     The voice recognition unit  102  analyzes the user&#39;s voice data acquired by the voice input/output unit  101  and converts the voice generated by the user into character string information. For example, when the user utters “e-a-ko-n”, the voice recognition unit  102  recognizes the voice by a string of “E”, “A”, “K O”, and “N” using a natural language processing technology. Incidentally, the conversion process from the voice data to the string is affected by the noise from the outside. For example, even when the user utters “e-a-ko-n”, the voice recognition unit  102  may recognize incorrectly some of the letters like “E”, “WA”, “K O”, and “N”. Such an error in voice recognition affects the value of accuracy, which will be described later. The voice recognition unit  102  recognizes the user&#39;s voice using an acoustic model and algorithm stored in the database. Then, the voice recognition unit  102  outputs the recognition result to the device identifying unit  103 . The voice recognition unit  102  records the data of the recognized voice in the database  30 . 
     The voice recognition unit  102 , when it is performing a dialogue between the user and the controller  100 , identifies a command corresponding to the character string from a character string recognized by the voice recognition and may output the response by voice data according to the command. For example, when the user issues “kyou no tenki ha? (it means “How is the weather today?” in English)”, the voice recognition unit  102  analyzes the user&#39;s voice data to generate a string in the order of “kyo”, “u”, “no”, “te”, “n”, “ki”, and “ha”. By connecting the strings, the voice recognition unit  102  can grasp the user&#39;s intention. Then, the voice recognition unit  102  generates the data of the sound that matches the grasped user&#39;s intention and outputs the data of the sound to the voice input/output unit  101 . In the above example, since the recognition unit  102  can recognize that the user asks the weather today, the voice recognition unit  102  outputs data of the sound such as “It is sunny today.”. Thus, the dialogue between the user and the controller  100  is realized. 
     Voice recognition unit  102  specifies which classification the utterance from the user corresponds to among the utterance of the operation request, the user response wait, and the dialogue cancellation request. The operation request indicates that the user is requesting operation of the device. The user response wait indicates a state in which the voice recognition unit is waiting for a response from the user. The dialogue cancellation request indicates that the user is requesting to cancel the dialogue with the system. 
     When the utterance from the user corresponds to the utterance of the operation request, the voice recognition unit  102  outputs the data of the character string specified by the voice recognition to the device specific unit  103 . 
     When the utterance from the user corresponds to the user response wait, the voice recognition unit  102  maintains a waiting state for the user&#39;s response for a predetermined period. In the present embodiment, when the wiper operation is specified based on the voice of the user, the voice recognition unit  102  performs confirmation with the user before operating the wiper because the wiper affects the driving operation of the user. In such a case, the voice recognition unit  102  is in a state of waiting for a user response. The voice recognition unit  102  may notify the user of the recognition result of the voice in the state of waiting for the user response. For example, when the wiper operation is identified based on the user&#39;s voice, the voice recognition unit  102  may output a voice such as “Would you like to operate the wiper?” to the user from the speaker  12 . By outputting such a voice, it is possible to confirm the correctness of the recognition result to the user. 
     When the utterance from the user corresponds to a dialogue cancellation request, the dialogue between the user and the controller  100  is cancelled. For example, when the user utters a “Stop the voice recognition system.” and the voice recognition unit  102  can recognize the user&#39;s intention, the dialogue is cancelled. 
     Device identifying unit  103  identifies the operation target device and the operation contents intended by the user based on the recognition result of the voice by the voice recognition unit  102 . Device identifying unit  103  refers to the data of the string (corresponding to the voice of the user) indicated by the recognition result and the device identification data recorded in the database  30  and identifies a name matching or similar to the name indicated by the string from the name of the device stored in the database. 
     Device identifying unit  103  refers to the data of the string (corresponding to the voice of the user) indicated by the recognition result and the operation identification data recorded in the database  30  from among the names of the operation contents stored in the database and identifies a name matching or similar to the name indicated by the string. 
     The device identifying unit  103 , when identifying the operation target device and the operation contents, calculates the value of the accuracy of them. The accuracy of the operation target device shows the similarity between voice data recognized from voice data and device identification data. The accuracy of operation contents shows similarity (similarity of character strings) between voice data recognized from voice data and operation identification data. The higher the value of the accuracy, the more likely it is that the device which the user wants to operate and the device identified in voice recognition correspond. The higher the value of the accuracy, the more likely it is that the operation which the user wants and the operation identified in voice recognition correspond. In other words, the accuracy of the operation target device and the accuracy of the operation contents indicate the accuracy of the recognition result in the voice recognition system. 
     The value of the accuracy is represented by, for example, a value from 0 to 1. When a plurality of devices can be identified from the voice data, the device identifying section  103  calculates the value of the accuracy for each identified device. When a plurality of operation contents can be identified from the voice data, the device identifying section  103  calculates the value of the accuracy for each identified operation content. 
     The device identifying unit  103  compares the calculated value of accuracy and the threshold value of accuracy. When the calculated value of accuracy is higher than the threshold value of accuracy, the device corresponding to the calculated accuracy is identified as the operation target device. The threshold value of accuracy is set in advance. Thus, the device identifying unit  103  identifies the operation target device based on the recognized voice. The device identification data are classified into driving-related device and non-driving-related device in the database  30 . Therefore, when the operation target device is identified, the classification of the operation target device is also specified. 
     The device identifying unit  103 , similarly for the operation contents, compares the calculated value of accuracy and the threshold value. When the calculated value of accuracy is higher than the threshold value of accuracy, the operation content corresponding to the calculated accuracy is specified as the operation content of the operation target device. Thus, the device identifying unit  103  identifies the operation contents of the operation target device based on the recognized voice. 
     The device identifying unit  103  transmits the information of identified operation device object, information of identified operation content, and a signal including information of accuracy to the operation command unit  104 , also records their information in the database  30 . When the controller  100  operates the device by the dialogue between the user and the controller  100 , the information of the operation target device, the operation contents, and the accuracy are held in the database  30  during the dialogue. The device identifying unit  103 , when the dialogue ends, or when the operation of the operation target device ends, resets the information held in the database. 
     The device identifying unit  103  compares the calculated value of accuracy and the threshold value of accuracy. When the calculated value of accuracy is equal to or less than the threshold value of accuracy, device identifying unit  103  outputs a signal for requesting re-uttering to the user to the voice recognition unit  102 . The device identifying unit  103 , when it is impossible to identify the operation target device, outputs a signal of the re-uttering request to the device identifying unit  103  in order to tell the name of the device to the user. Further, the device identifying unit  103 , when it is not possible to identify the operation contents, outputs a signal of the re-uttering request to the device identifying unit  103  in order to tell the operation contents in words to the user. Further, the device identifying unit  103 , when it is impossible to calculate the value of the accuracy from the voice data recognized by the voice recognition, outputs a signal for requesting a re-utterance to the user to the voice recognition unit  102 . 
     The operation command unit  104  controls the operation target device based on the information of the operation target device and the operation contents. The operation command unit  104  controls the timing to activate the target device in the operation content depending on the type of the target device. 
     The value of the accuracy of voice recognition by the voice recognition system may be lowered by the voice quality of the user and the sound in the cabin, etc.. Therefore, when the device is activated by the user&#39;s voice, it is also conceivable to confirm the user&#39;s intention by using the dialogue between the user and the system prior to starting operation for all device operations. However, in the case of confirming the intention of the user for the operation of all devices, since it takes time for the dialogue by voice recognition, the time from the user&#39;s voice to the operation of the device increase. 
     In the present embodiment, the controller  100  classifies the type of a plurality of devices a device requiring or not requiring a response from the user to control the operation timing. In other words, when the device requires a response from the user, the controller  100  notifies the user to confirm whether or not the device should be operated, and when the controller confirms that the user wants the device is operated, the controller  100  turns the device activate. Notification to the user is made by a dialogue between the user and the controller  100 . In addition, when the device does not require a response from the user, the controller  100  does not notify the user to confirm whether or not the device should be operated, and activate the device. When the operation target device is a device that does not require a response from the user, the controller  100  may notify the user that the operation of the device starts to activate the device without waiting for a response from the user. 
     As described above, the types of multiple devices are divided into driving-related device and non-driving-related device. The operation command unit  104 , when the operation target device is a driving-related device, performs dialogue with the user prior to operating in identified operation content. When the operation target device is a non-driving related device, the operation command unit  104  controls the operation timing in accordance with the accuracy of the voice recognition result. In other words, when the value of the accuracy is equal to or greater than the threshold value, the operation command unit  104  does not check the operation to the user and activate the operation target device in identified operation content. When the value of the accuracy is less than the threshold value, the operation command unit  104  performs operation check with the user prior to activate the operation target device with identified operation details. Then, the operation command unit  104  transmits a command value indicating identified operation content to the operation target device. 
     Next, with reference to  FIG. 3 , a control flow of the controller  100 .  FIG. 3  is a flowchart showing a control flow of the controller  100 . The control flow illustrated in  FIG. 3  is repeatedly executed at a predetermined cycle. 
     In step S  1 , the controller  100  uses a microphone  11  to acquire the voice of the user. In step S 2 , the controller  100  executes a voice recognition processing. The voice recognition processing is processed by a voice recognition system for recognizing the voice of a user using the voice data output from the microphone  11 . The controller  100  stores the voice data recognized in the database  30 . That is, the controller  100  executes the storage control for storing the data indicating the recognition result of the voice in the database  30  and the voice recognition control in parallel. Thus, it is possible to increase the accuracy of voice recognition since the past recognition results can be utilized in voice recognition processing. 
     In step S 3 , the controller  100  determines whether or not a new voice is recognized from the result of the voice recognition processing. The new voice is a voice for initiating a dialogue between the user and the controller  100 . When it is determined that a new voice is recognized, the controller  100  makes it possible to interact with the user. For example, when the voice recognition system has a noise canceling function in order to increase the voice recognition accuracy, the controller  100  keeps the noise canceling function operating. The controller  100  executes the control flow of step S 1  when it is determined that the new voice is not recognized. The control loop in steps S 1  to S 3  is repeatedly executed so that a state waiting for an utterance from the user is maintained. 
     In step S 4 , the controller  100  starts the device identification processing for identifying the operation target device and the operation contents based on the voice recognized. In step S 5 , the controller  100  determines whether or not the user is intended for device operation. For example, when a character string recognized by voice recognition does not fall under the name indicated by the device identification data, the controller  100  determines that the user is not intend ed for device operation and executes the control flow of step S 1 . The controller  100  also calculates the value of the accuracy for the identified voice. 
     When it is determined that the user is intended for device operation is intended, in step S 6 , the controller  100  compares the calculated value of the accuracy with the accuracy threshold value, and determines whether or not the operation target device can be specified based on the comparison result. When it is impossible to identify the operation target device, the controller  100  executes the control flow of step S 1 . At this time the controller  100  may output a voice from the speaker  12  for telling that the operation target device could not be identified and for requesting the user to re-utterance. 
     When it is determined that the operation target device can be identified, in step S 7 , the controller  100  compares the calculated value of the accuracy with the accuracy threshold value, and determines whether or not the operation contents corresponding to the operation target device can be identified. When the operation contents cannot be identified, the controller  100  executes the control flow of step S 1 . At this time, the controller  100  may output a voice from the speaker  12  for telling that the operation contents could not be identified and may for requesting the user to re-utterance. 
     As described above, when it is impossible to identify at least one of the operation target device and the operation contents based on the voice recognized, the controller  100  requests a re-utterance to the user. This allows the user to quickly understand what to do to operate the device. 
     In step S 8 , the controller  100  determines whether the operation target device and the operation contents correspond. When the operation target device and the operation content do not correspond to each other, the controller  100  executes the control flow of step S 17 . 
     When the operation target device and the operation contents correspond, in step S 9 , the controller  100  determines whether or not the type of identified operation target device corresponds to the driving-related device. When the operation target device corresponds to a driving-related device, in Step S 10 , the controller  100  performs a notification (hereinafter, referred to as the operation confirmation) by voice to the user to confirm whether or not the user is intended to activate the operation target device. For example, when the wiper is identified as an operation target device, the controller  100  outputs a sound such as “Do you operate the wiper?” from the speaker  12 . 
     In step S 11 , the controller  100  holds a standby state waiting for a re-utterance by the user. When the controller  100  confirms the response to activate the device from the user while waiting for a re-utterance, it activates the device in the control flow of step S 16 , which will be described later. 
     In the control flow of step S 9 , when it is determined that the type of identified operation target device does not fall under the driving-related device (that is, when it is determined that the type of identified operation target device falls under the non-driving-related device), the controller  100  determines whether the value of the accuracy of the voice recognition result is equal to or greater than the determination threshold value. 
     When the value of the accuracy of the voice recognition result is less than the determination threshold value, the controller  100  performs an operation check by voice to the user in step S 13 . In step S 14 , the controller  100  holds a standby state waiting for a re-utterance by the user. When the controller  100  confirms the response to activate the device from the user while waiting for a re-utterance, it activates the device in the control flow of step S 16 , which will be described later. 
     In step S 15 , the controller  100  determines whether or not recognized voice indicating an error within a predetermined period from the time of starting the standby state by the control processing in step S  11  or step S 14 . When the voice indicating an error within a predetermined period is recognized by the voice recognition processing, the controller  100  executes the control processing of step S 18 . When the voice indicating the error is not recognized within a predetermined time, the controller  100  executes the control flow of step S 16 . 
     When it is determined that the value of the accuracy of the voice recognition result is equal to or more than the determination threshold value in the control flow of step S 12 , the controller  100  executes the control flow of step S 16  without performing operation confirmation by voice such as the control flow of step S 10  or step S 13 . Note that, in steps from S 12  to S 16 , a notification of start of activating the identified operation target device may be performed before activating the identified operation target device. For example, when the operation target device is an “air conditioner” and the operation content is “21° C”, the notification content in this case is a notification that “set the air conditioner to 21° C”. In other words, when the identified operation target device is a non-driving-related device and the value of the accuracy of the voice recognition result is equal to or greater than the threshold value, no notification is given to the user to confirm to activate the device, but a one-way notification to tell starting the operation of the operation target device may be given. 
     In step S 16 , the controller  100  activates identified operation target device by identified operation content. When identified operation device object is a driving-related device, the controller  100  performs an operation check in the control flow of step S 10 . When the controller confirms a response to activate the device from the user in the control flow of step S  11  and step S 15 , the controller  100  activates the operation target device. When identified operation device target is a non-driving-related device and the value of the accuracy of the voice recognition result is less than the threshold, the operation is confirmed in the control flow of step S 13  . When the response to activate the device from the user in the control flow of steps S 14  and S 15 , the controller  100  activates the operation-target device. The controller  100  may perform operation check again when it is impossible to confirm the response from the user within a predetermined period after the operation check in the control flow of step S 10  or step S 13  . The controller  100  may notify the user that the voice recognition processing ceases without operating the device when it is impossible to confirm the response from the user within a predetermined period after performing the operation check in the control flow of step S 10  or step S 13 . 
     When it is determined that the operation target device and the operation contents do not correspond in the control flow of step S 8 , the controller  100  outputs an error message from the speaker  12  in step S 17 . An error message indicates that the operation details cannot be identified or that the operation target device cannot be identified. In step S 18 , the controller  100  outputs a voice from the speaker  12  for requesting a re-utterance to the user and executes the control processing of step S 1 . 
     In the above-described embodiment, each hardware described in  FIG. 1  is exemplified as a device mounted on a vehicle, but a part of the hardware described in  FIG. 1  or a part of the function of the controller  100  described in  FIG. 2  may be realized by a part of a server connected by a network. For example, the voice recognition unit  102  may be provided in a server connected by a network, and the voice data from the voice input/output unit  101  provided in the vehicle may be received to transmit the result recognized by the voice to the vehicle. Further, a portion of the hardware described in  FIG. 1  or a portion of the function of the controller  100  described in  FIG. 2  may be realized by a mobile terminal connected by a network. For example, a mobile device having a voice input unit  101  and a voice recognition unit  102  may perform voice recognition of the user&#39;s utterance and interactions with the user and may be configured to transmit the results recognized by the voice to the vehicle. 
     As described above, in the present embodiment, the device control apparatus recognizes the voice using the sound data detected by the detector, identifies the type of the operation target device to be operated from among the plurality of devices and the operation contents of the operation target device based on the recognized voice, and controls the timing to activate the operation target device by the operation contents according to the type of identified operation target device. Thus, it is possible to accelerate the operation timing according to the type of device. As a result, the time from the user speaking to the time operating the device can be shortened. 
     In the present embodiment, when identified operation target is the first device, the first device is operated by identified operation content, and when identified operation target is the second device (the electronic component that differs in type from the first device), a notification is issued to the user in advance of activating the second device by identified operation content. Thus, in the case of operating a device requiring operation confirmation to the user in voice recognition, since the notification for requesting a response to the user is performed, the optimum target device transmission process and the operation execution process can be executed. 
     Further, in the present embodiment, the device control apparatus distinguishes the type of a plurality of devices into the non-driving-related devices (corresponding to the first device) and the driving-related devices (corresponding to the second device). Thus, whether or not the operation target device affects the behavior or driving operation of the vehicle, it is possible to select the target device transmission process and the operation execution process properly according to whether or not the operation target device affects the driving operation of the vehicle. 
     In this embodiment, when identified operation target is a non-driving-related device, the non-driving-related device is activated by identified operation content without notifying the user. Thus, since the transition to direct operation without performing the operation confirmation to the user, it is possible to execute the operation promptly without making the user wait. 
     In the present embodiment, when identified operation target is a non-driving-related-device, the non-driving-related device is activated in identified operation content without giving notification to the user to request a response. Thus, since the transition to direct operation without performing the operation confirmation to the user, it is possible to execute the operation promptly without making the user wait. 
     In the present embodiment, the device control apparatus stores the data of the voice, the data indicating the type of the operation target device, and the data indicating the operation contents in the database, refers to the data stored in the database, and identifies to identify the operation target device and the operation contents corresponding to the voice detected by the microphone  11  (corresponding to the detector). Thus, it is possible to increase the accuracy of voice recognition. 
     Further, in the present embodiment, the device control apparatus executes in parallel a voice recognition control for recognizing the voice and the device specific control for identifying the type and operation contents of the operation target device. Thus, after the utterance of the user, it is possible to promptly execute the device specific control. 
     In the present embodiment, the value of the accuracy indicating the recognition result of the operation target device and the operation contents is calculated. The device control apparatus can execute the optimum processing using the accuracy. 
     In the present embodiment, the recognition result of the user&#39;s voice is notified to the user. Thus, since the device control apparatus can check whether the recognition result is correct or not, it is possible to quickly move to the request of execution or re-utterance of the operation. 
     In the present embodiment, the device control apparatus performs dialogue with the user by outputting a sound using a speaker in response to the recognized voice, and stops the dialogue in accordance with the recognition result of the voice. Since the device control apparatus can grasp the intention of the user in this way, it is possible to immediately stop the dialogue. 
     As shown in  FIG. 3 , when at least one of the operation target device and the operation content cannot be specified, one of the control flow in steps S 1  to S 7  and the control flow in steps S 1  to S 8  is executed. 
     In a modification of the embodiment, while the control loop is repeatedly executed, when a predetermined time has elapsed in a state in which at least one of the operation target device and the operation content can not be specified, the controller  100  requests a re-utterance to the user. Thus, since the shortage of information necessary for device operation can be communicated to the user, it is possible to require the user to supplement the information. 
     In another modification of the present embodiment, while the control loop is repeatedly executed, when a predetermined time has elapsed in a state of the calculated value of the accuracy less than or equal to a predetermined value, it requests a re-utterance to the user. Thus, it is possible to prevent the unstable operation of the system due to insufficient accuracy, since the accuracy requires a re-utterance when it is less than the threshold value. 
     In another modification of the present embodiment, before the lapse of the above predetermined period, when identifying the error of the recognition result of the voice from the dialogue with the user, it requests a re-utterance to the user. Thus, it is possible to quickly shift to re-utterance without waiting for the request of re-utterance. 
     In another modification of the present embodiment, when identified operation target is a driving-related device, the device control apparatus activates the device that differs from the driving-related device before activating the driving-related device in the identified operation content. Controller  100  may illuminate the lamp as a device different from the driving-related device. The lamp indicates the start of operation of a particular driving-related device by flashing. Thus, the user can recognize that the operation target is a driving-related device before the driving-related device operates. 
     In another modification of the present embodiment, when identified operation target is a non-driving-related device, the device control apparatus activates the non-driving-related device in the predetermined operation content prior to activate of the non-driving-related device in identified operation content. As an example, when the user&#39;s request is to reduce the air volume of the air conditioner, the controller  100  repeats the operation several times to reduce the air volume of the air conditioner for a slight time of about 0.2 seconds. “Reduce the air volume” intended by the user is intended to reduce the air volume for a long time not a few seconds, but the controller reduces the air volume for a short time as an operation different from identified operation content. Thus, the user can recognize that the air conditioner is an operation object. As another example, when the user&#39;s purpose is to “set the radio to radio station AA,” the device control apparatus conveys that the audio is to be operated to the user by flowing a unique sound for a small amount of time, about 0.2 seconds, from the audio. Thus, it is possible to communicate the operation target device safely and promptly to the user. 
     In another modification of the present embodiment, based on the recognized voice, when it is impossible to identify at least one of the operation target device and the operation contents, and outputs a sound or light from the out put device. The device control apparatus can transmit the operation target to the user by an illumination indicative of the operation of the driving-related device. Since the transmission in a short time by the alarm sound or light, it is possible to quickly re-utterance and the voice recognition. The output device may be a speaker  12 . 
     In the control flow of step S 10 , the device control apparatus outputs a voice to the user but it may convey the information of the operation target device to the user by the inherent operation of the non-driving-related device  152 . For example, when non-driving-related device  152  is audio, the inherent operation corresponds to an inherent sound. 
     EXPLANATIONS OF LETTERS OR NUMERALS 
       1  . . . Device control apparatus 
       11  . . . Microphone 
       12  . . . Speaker 
       21  . . . Wiper 
       22  . . . Light 
       23  . . . Audio 
       24  . . . Air conditioner 
       30  . . . Database 
       100  . . . Controller 
       101  . . . Voice input/output unit 
       102  . . . Voice recognition unit 
       103  . . . Device identifying unit 
       104  . . . Operation command unit