Audio output device, audio output method, program, and storage medium

Abstract

This audio output device includes an acquisition unit for acquiring a positioning accuracy of a GPS, and an audio guidance unit for performing an audio guidance using information independent on the position of a mobile object if the positioning accuracy is lower than the reference value.

Description

[Technical field]

[0001] The present invention relates to a technique that can be used in audio output. [Background technology]

[0002] In a car navigation device or the like, if the positioning accuracy of a GPS (Global Positioning System) drops during route guidance, the positioning accuracy of the current position drops, making accurate guidance difficult. Patent Document 1 proposes a method for providing a vehicle application execution device that is capable of executing applications even in a situation where GPS radio waves are blocked when a vehicle is equipped with multiple applications that have different position accuracy requirements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-106790 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, even with Patent Document 1, applications that require relatively high positional accuracy, such as route guidance and distance measurement applications, cannot necessarily be executed in a situation where GPS radio waves are blocked.

[0005] The present invention has been made to solve the above-mentioned problems, and has as its main object to prevent a decrease in guidance accuracy even when the positioning accuracy of GPS decreases. [Means for solving the problem]

[0006] The invention described in the claims is a voice output device, comprising: an acquisition unit that acquires a positioning accuracy of a GPS; and a voice guidance unit that performs voice guidance using information that does not depend on the position of a moving object when the positioning accuracy is lower than a reference value. When the positioning accuracy is no longer equal to or greater than the reference value, the voice guidance unit outputs voice guidance regarding the next guide point. do.

[0007] The invention described in the claims is a voice output method executed by a voice output device, comprising: an acquisition step of acquiring a positioning accuracy of a GPS; and a voice guidance step of providing voice guidance using information that does not depend on the position of a moving object when the positioning accuracy is lower than a reference value. The voice guidance step includes outputting voice guidance regarding a next guide point when the positioning accuracy is no longer equal to or greater than the reference value. do.

[0008] The claimed invention is a program executed by a content output device having a computer, the program causing the computer to function as an acquisition means for acquiring GPS positioning accuracy, and as a voice guidance means for providing voice guidance using information that is not dependent on the position of a moving object when the positioning accuracy is lower than a reference value. When the positioning accuracy is no longer equal to or greater than the reference value, the voice guidance means outputs a voice guidance regarding a next guide point. do. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a voice output system according to an embodiment. [Diagram 2] FIG. 1 is a block diagram showing a schematic configuration of an audio output device. [Diagram 3] FIG. 2 is a diagram showing an example of a schematic configuration of a server device. [Figure 4] 4 is a flowchart illustrating a process performed in the audio output device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In one preferred embodiment of the present invention, the audio output device includes an acquisition unit that acquires GPS positioning accuracy, and an audio guidance unit that provides audio guidance using information that is not dependent on the position of a moving object when the positioning accuracy is lower than a reference value.

[0011] The above voice output device obtains the positioning accuracy of the GPS, and when the positioning accuracy is lower than a reference value, provides voice guidance using information that is not dependent on the position of the moving object. This makes it possible to prevent the accuracy of route guidance from decreasing even if the positioning accuracy of the GPS decreases.

[0012] In another aspect of the above-mentioned voice output device, the voice guidance unit uses information on landmarks at the guidance point. In this aspect, the voice output device can provide voice guidance using information that is not dependent on the position of the moving object.

[0013] In another aspect of the above voice output device, the voice guidance unit outputs voice guidance regarding the next guide point when the positioning accuracy is no longer equal to or greater than the reference value. In this aspect, the user can grasp information regarding the next guide point in advance.

[0014] In another aspect of the above-mentioned audio output device, when the positioning accuracy is no longer equal to or greater than the reference value, the audio guidance unit outputs a message indicating that the positioning accuracy is decreasing. In this aspect, it becomes possible for a user to understand that the positioning accuracy is decreasing.

[0015] In another aspect of the above voice output device, when the positioning accuracy is no longer equal to or greater than the reference value, the voice guidance unit outputs a message indicating that the positioning accuracy is deteriorating and voice guidance regarding the next guide point. In this aspect, the user can understand that the positioning accuracy is deteriorating, and further, can grasp information regarding the next guide point in advance.

[0016] In another aspect of the above audio output device, the acquisition unit acquires the positioning accuracy based on map data. In this aspect, the audio output device can acquire the positioning accuracy based on the map data.

[0017] According to another preferred embodiment of the present invention, a voice output method executed by a voice output device includes an acquisition step of acquiring a positioning accuracy of a GPS, and a voice guidance step of providing voice guidance using information that does not depend on the position of a moving object when the positioning accuracy is lower than a reference value. This makes it possible to prevent a decrease in the accuracy of route guidance even if the positioning accuracy of the GPS decreases.

[0018] According to another preferred embodiment of the present invention, a program executed by a computer causes the computer to function as an acquisition means for acquiring the positioning accuracy of the GPS, and as a voice guidance means for providing voice guidance using information that does not depend on the position of the moving object when the positioning accuracy is lower than a reference value. By executing this program on a computer, the above-mentioned voice output device can be realized. This program can be stored in a storage medium and handled. EXAMPLES

[0019] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0020] [System Configuration] (Overall composition) 1 is a diagram showing a configuration example of an audio output system according to an embodiment. The audio output system 1 according to the embodiment includes an audio output device 100 and a server device 200. The audio output device 100 is mounted on a vehicle Ve. The server device 200 communicates with a plurality of audio output devices 100 mounted on a plurality of vehicles Ve.

[0021] The audio output device 100 basically performs route search processing, route guidance processing, and the like for a user who is a passenger of a vehicle Ve. For example, when a destination or the like is input by a user, the audio output device 100 transmits an upload signal S1 including position information of the vehicle Ve and information related to the specified destination to the server device 200. The server device 200 calculates a route to the destination by referring to map data, and transmits a control signal S2 indicating the route to the destination to the audio output device 100. The audio output device 100 provides route guidance to the user by audio output based on the received control signal S2.

[0022] Furthermore, the audio output device 100 provides various types of information to the user through dialogue with the user. For example, when the user makes an information request, the audio output device 100 supplies the server device 200 with an upload signal S1 including information indicating the content or type of the information request and information regarding the running state of the vehicle Ve. The server device 200 acquires and generates the information requested by the user and transmits it to the audio output device 100 as a control signal S2. The audio output device 100 provides the received information to the user by audio output.

[0023] (Audio output device) The audio output device 100 moves together with the vehicle Ve and provides route guidance mainly through audio so that the vehicle Ve travels along the guide route. Note that "route guidance mainly through audio" refers to route guidance that allows the user to grasp information necessary for driving the vehicle Ve along the guide route at least from audio alone, and does not exclude the audio output device 100 displaying a map around the current position as an auxiliary. In this embodiment, the audio output device 100 outputs various information related to driving by audio, such as at least points on the route where guidance is required (also called "guidance points"). Here, the guidance points correspond to, for example, intersections where the vehicle Ve must turn right or left, and other important passing points for the vehicle Ve to travel along the guide route. The audio output device 100 provides audio guidance related to the guidance points, such as the distance from the vehicle Ve to the next guidance point and the traveling direction at the guidance point. Hereinafter, the audio related to the guidance for the guide route will also be called "route audio guidance".

[0024] The audio output device 100 is attached, for example, to an upper portion of a windshield or on a dashboard of the vehicle Ve. The audio output device 100 may be built into the vehicle Ve.

[0025] 2 is a block diagram showing a schematic configuration of the audio output device 100. The audio output device 100 mainly includes a communication unit 111, a storage unit 112, an input unit 113, a control unit 114, a sensor group 115, a display unit 116, a microphone 117, a speaker 118, an outside-vehicle camera 119, and an inside-vehicle camera 120. The elements in the audio output device 100 are connected to each other via a bus line 110.

[0026] The communication unit 111 performs data communication with the server device 200 under the control of the control unit 114. The communication unit 111 may receive, for example, map data for updating a map DB (DataBase) 4 (described later) from the server device 200.

[0027] The storage unit 112 is configured with various types of memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), and a non-volatile memory (including a hard disk drive, a flash memory, etc.). The storage unit 112 stores programs for the audio output device 100 to execute predetermined processes. The above-mentioned programs may include an application program for providing route guidance by voice, an application program for playing music, and an application program for outputting content other than music (such as television). The storage unit 112 is also used as a working memory for the control unit 114. The programs executed by the audio output device 100 may be stored in a storage medium other than the storage unit 112.

[0028] The storage unit 112 also stores a map database (hereinafter, database will be referred to as "DB") 4. Various data necessary for route guidance is recorded in the map DB 4. The map DB 4 stores, for example, road data that represents a road network by a combination of nodes and links, and facility data that indicates facilities that are candidates for a destination, a stop-off point, or a landmark. The map DB 4 may be updated based on map information that the communication unit 111 receives from a map management server under the control of the control unit 114.

[0029] The input unit 113 is a button, a touch panel, a remote controller, etc. that is operated by the user. The display unit 116 is a display or the like that displays information based on the control of the control unit 114. The microphone 117 collects sounds inside the vehicle Ve, particularly sounds uttered by the driver, etc. The speaker 118 outputs sounds for route guidance to the driver, etc.

[0030] The sensor group 115 includes an external sensor 121 and an internal sensor 122. The external sensor 121 is one or more sensors for recognizing the surrounding environment of the vehicle Ve, such as a lidar, a radar, an ultrasonic sensor, an infrared sensor, or a sonar. The internal sensor 122 is a sensor for measuring the position of the vehicle Ve, such as a Global Navigation Satellite System (GNSS) receiver, a gyro sensor, an Inertial Measurement Unit (IMU), a vehicle speed sensor, or a combination of these. Note that the sensor group 115 may include any sensor that allows the control unit 114 to directly or indirectly (i.e., by performing an estimation process) derive the position of the vehicle Ve from the output of the sensor group 115.

[0031] The exterior camera 119 is a camera that captures the outside of the vehicle Ve. The exterior camera 119 may be only a front camera that captures the view in front of the vehicle, or may include a rear camera that captures the view behind the vehicle in addition to the front camera, or may be an omnidirectional camera that can capture the entire surroundings of the vehicle Ve. On the other hand, the interior camera 120 is a camera that captures the inside of the vehicle Ve, and is provided at a position that can capture at least the area around the driver's seat.

[0032] The control unit 114 includes a central processing unit (CPU), a graphics processing unit (GPU), and the like, and controls the entire audio output device 100. For example, the control unit 114 estimates the position (including the direction of travel) of the vehicle Ve based on the output of one or more sensors of the sensor group 115. Furthermore, when a destination is specified by the input unit 113 or the microphone 117, the control unit 114 generates route information indicating a guide route that is a route to the destination, and performs route guidance based on the route information, the estimated position information of the vehicle Ve, and the map DB4. In this case, the control unit 114 causes the speaker 118 to output route voice guidance. Furthermore, the control unit 114 controls the display unit 116 to display information on the music being played, video content, a map of the surroundings of the current position, and the like.

[0033] The processing executed by the control unit 114 is not limited to being realized by software using a program, but may be realized by any combination of hardware, firmware, and software. The processing executed by the control unit 114 may be realized by using an integrated circuit programmable by a user, such as an FPGA (field-programmable gate array) or a microcomputer. In this case, the program executed by the control unit 114 in this embodiment may be realized by using this integrated circuit. In this way, the control unit 114 may be realized by hardware other than a processor.

[0034] The configuration of the audio output device 100 shown in FIG. 2 is an example, and various modifications may be made to the configuration shown in FIG. 2. For example, instead of the map DB4 being stored in the storage unit 112, the control unit 114 may receive information necessary for route guidance from the server device 200 via the communication unit 111. In another example, instead of including the speaker 118, the audio output device 100 may be electrically connected to an audio output unit configured separately from the audio output device 100 or by a known communication means, thereby outputting audio from the audio output unit. In this case, the audio output unit may be a speaker provided in the vehicle Ve. In yet another example, the audio output device 100 may not include the display unit 116. In this case, the audio output device 100 may not perform any control regarding the display, and may be electrically connected to a display unit provided in the vehicle Ve or the like by wire or wirelessly, thereby causing the display unit to execute a predetermined display. Similarly, instead of including the sensor group 115, the audio output device 100 may acquire information output by a sensor provided in the vehicle Ve from the vehicle Ve based on a communication protocol such as CAN (Controller Area Network).

[0035] (Server device) The server device 200 generates route information indicating a guide route along which the vehicle Ve should travel, based on an upload signal S1 including a destination and the like received from the audio output device 100. The server device 200 then generates a control signal S2 related to information output in response to the user's information request, based on the user's information request and the traveling state of the vehicle Ve indicated in the upload signal S1 transmitted thereafter by the audio output device 100. The server device 200 then transmits the generated control signal S2 to the audio output device 100.

[0036] Furthermore, the server device 200 generates content for providing information to the user of the vehicle Ve and for dialogue with the user, and transmits the content to the audio output device 100. Information provided to the user is mainly push-type information provided from the server device 200 side, triggered by the vehicle Ve entering a predetermined driving situation. Also, dialogue with the user is basically pull-type dialogue that is initiated by a question or inquiry from the user. However, dialogue with the user may also be initiated by push-type content provision.

[0037] 3 is a diagram showing an example of a schematic configuration of the server device 200. The server device 200 mainly includes a communication unit 211, a storage unit 212, and a control unit 214. The elements in the server device 200 are connected to each other via a bus line 210.

[0038] The communication unit 211 performs data communication with external devices such as the audio output device 100 under the control of the control unit 214. The storage unit 212 is composed of various types of memory such as RAM, ROM, and non-volatile memory (including a hard disk drive, a flash memory, etc.). The storage unit 212 stores a program for the server device 200 to execute a predetermined process. The storage unit 212 also includes a map DB4.

[0039] The control unit 214 includes a CPU, a GPU, and the like, and controls the entire server device 200. The control unit 214 also executes a program stored in the storage unit 212 to operate together with the audio output device 100 and executes route guidance processing and information provision processing for the user. For example, the control unit 214 generates route information indicating a guidance route or a control signal S2 related to information output in response to an information request from the user, based on an upload signal S1 received from the audio output device 100 via the communication unit 211. Then, the control unit 214 transmits the generated control signal S2 to the audio output device 100 via the communication unit 211.

[0040] [Push-type content provision] Next, push-type content provision will be described. Push-type content provision means that when the vehicle Ve is in a predetermined driving state, the audio output device 100 outputs audio content related to the driving state to the user. Specifically, the audio output device 100 acquires driving state information indicating the driving state of the vehicle Ve based on the output of the sensor group 115 as described above, and transmits the information to the server device 200. The server device 200 stores table data for performing push-type content provision in the storage unit 212. The server device 200 refers to the table data, and when the driving state information received from the audio output device 100 mounted on the vehicle Ve matches a trigger condition defined in the table data, the server device 200 acquires output content using text data corresponding to the trigger condition and transmits the content to the audio output device 100. The audio output device 100 outputs the output content received from the server device 200 as audio. In this way, the content corresponding to the driving state of the vehicle Ve is output as audio to the user.

[0041] The driving situation information may include at least one piece of information that can be acquired based on the functions of each unit of the audio output device 100, such as the position of the vehicle Ve, the direction of the vehicle, traffic information (including speed restrictions and congestion information, etc.) around the position of the vehicle Ve, the current time, the destination, etc. The driving situation information may also include any of the voice (excluding the user's speech) acquired by the microphone 117, the image captured by the outside camera 119, and the image captured by the inside camera 120. The driving situation information may also include information received from the server device 200 via the communication unit 111.

[0042] [Guidance based on GPS positioning accuracy] Next, guidance according to the positioning accuracy of GPS will be described. Guidance according to the positioning accuracy of GPS means that the audio output device 100 calculates the positioning accuracy of GPS and changes the guidance content at the guide point according to the result. Specifically, during route guidance of the vehicle equipped with the audio output device 100, the audio output device 100 uses satellite signals of GPS satellites to measure the current position of the vehicle (hereinafter, referred to as "own vehicle position") and calculates the positioning accuracy of the own vehicle position. Then, when the vehicle reaches the guide point, the audio output device 100 judges whether the positioning accuracy of GPS is equal to or higher than a predetermined reference value, and provides audio guidance to the user based on the judgment result. Note that factors that cause the positioning accuracy to decrease include a case where the reception level of the GPS signal is decreased underground or in a tunnel, or a case where the GPS signal becomes multipath.

[0043] Here, if the positioning accuracy of the GPS is not equal to or greater than a predetermined reference value, the accuracy of the current position of the vehicle and the accuracy of the distance from the current position of the vehicle to the guide point will be low. Therefore, the audio output device 100 provides audio guidance using information that is not dependent on the current position of the vehicle or the distance from the current position of the vehicle to the guide point. Examples of information that is not dependent on the current position of the vehicle or the distance from the current position of the vehicle to the guide point include landmarks such as intersections and facilities. For example, if the positioning accuracy of the GPS is not equal to or greater than a predetermined reference value, the audio output device 100 provides audio guidance such as "Turn right at XX intersection."

[0044] On the other hand, when the positioning accuracy of the GPS is equal to or higher than a predetermined reference value, the voice output device 100 performs voice guidance using information on the current position of the vehicle and the distance from the current position of the vehicle to the guide point. For example, when the positioning accuracy of the GPS is equal to or higher than a predetermined reference value, the voice output device 100 performs voice guidance such as "Turn right 300 m ahead."

[0045] (Processing flow) FIG. 4 is a flowchart for explaining the process performed in the voice guidance device.

[0046] This process is realized by the control unit 114 shown in Fig. 2 executing a program prepared in advance. This process is repeatedly executed at predetermined time intervals during route guidance by the audio output device 100.

[0047] The control unit 114 determines whether the vehicle has reached a guidance output point based on the vehicle position of the vehicle equipped with the voice output device 100 and map information (step S11). The "guidance output point" is a point where voice guidance regarding the next guidance point should be output, and is usually set to a point where the distance to the next guidance point is less than a predetermined distance. If the vehicle has not reached the guidance output point (step S11: No), the process ends.

[0048] On the other hand, when the vehicle has reached the guidance output point (step S11: Yes), the control unit 114 acquires the positioning accuracy of the GPS (step S12) and judges whether the positioning accuracy of the GPS is equal to or higher than a predetermined reference value (step S13). When the positioning accuracy of the GPS is equal to or higher than the predetermined reference value (step S13: Yes), the control unit 114 performs route guidance using distance information (step S14). For example, the control unit 114 outputs a guidance voice such as "Turn right at 300 m ahead" as described above. On the other hand, when the positioning accuracy of the GPS is not equal to or higher than the predetermined reference value (step S13: No), the control unit 114 performs route guidance using landmarks such as intersections (step S15). For example, the control unit 114 outputs a voice guidance such as "Turn right at XX intersection" as described above.

[0049] Next, the control unit 114 determines whether the vehicle has reached the destination based on the vehicle's own position and the information of the preset guide route (step S16). If the vehicle has not reached the destination (step S16: No), the process returns to step S11 and continues. On the other hand, if the vehicle has reached the destination (step S16: Yes), the process ends.

[0050] [Variations] Preferred modifications of the above-described embodiment will now be described. These modifications can be applied to the above-described embodiment in any combination. (Variation 1-1) In the above embodiment, when the voice output device 100 arrives at a guidance output point, it judges whether the positioning accuracy of the GPS is equal to or greater than a predetermined reference value, and performs voice guidance based on the judgment result, but the application of the present disclosure is not limited to this. For example, the voice output device 100 may constantly judge whether the positioning accuracy of the GPS is equal to or greater than a predetermined reference value. Then, when the positioning accuracy of the GPS is no longer equal to or greater than the predetermined reference value, the voice output device 100 provides voice guidance of information regarding the next guide point regardless of whether it is the timing of the original voice guidance. In this case, the information regarding the next guide point is information that does not depend on the current position of the vehicle or the distance from the current position of the vehicle to the guide point. As a result, even if the user enters an area with low GPS positioning accuracy, the user can know the next guide point in advance, and anxiety during driving is reduced.

[0051] (Variation 1-2) Also, similarly to the above-mentioned modified example 1-1, the audio output device 100 may constantly determine whether the GPS positioning accuracy is equal to or greater than a predetermined reference value, and when the GPS positioning accuracy is no longer equal to or greater than the predetermined reference value, provide audio guidance to the effect that the GPS positioning accuracy is deteriorating. For example, when the GPS positioning accuracy is no longer equal to or greater than the predetermined reference value, the audio output device 100 provides audio guidance such as "GPS positioning accuracy is deteriorating." This allows the user to understand that the positioning accuracy is deteriorating.

[0052] (Variation 1-3) Furthermore, the above-mentioned modified example 1-1 and modified example 1-2 may be combined. That is, the audio output device 100 may constantly determine whether the positioning accuracy of the GPS is equal to or greater than a predetermined reference value, and when the positioning accuracy of the GPS is no longer equal to or greater than the predetermined reference value, may provide voice guidance to the effect that the positioning accuracy of the GPS has decreased and information on the next guide point. For example, when the positioning accuracy of the GPS is no longer equal to or greater than a predetermined reference value, the audio output device 100 may provide voice guidance such as "Since the positioning accuracy of the GPS has decreased, we will inform you of the next guide point. Turn right at the XX intersection." Also, for example, the audio output device 100 may further add landmark information that is information that does not depend on the position of the moving object and notify the user, such as "Since the positioning accuracy of the GPS has decreased, we will inform you of the next guide point. Turn right at the XX intersection, which is the intersection facing the XX convenience store." or "Since the positioning accuracy of the GPS has decreased, we will inform you of the next guide point. Proceed in the direction of XX at the XX junction, which is the first branch point in the tunnel." This allows the user to know that the positioning accuracy has decreased and to receive information regarding the next guide point, thereby reducing anxiety while driving.

[0053] (Variation 2) In the above embodiment, the audio output device 100 calculates the positioning accuracy for the current position and determines whether the GPS positioning accuracy is equal to or greater than a predetermined reference value, but the application of the present disclosure is not limited to this. For example, the audio output device 100 may obtain the positioning accuracy from the map data of the server device 200. Specifically, the multiple audio output devices 100 mounted on the multiple vehicles Ve transmit the positioning accuracy calculated during route guidance to the server device 200, and the server device 200 reflects the received positioning accuracy in the map data in advance. Then, the audio output device 100 may obtain the positioning accuracy from the map data during subsequent route guidance, and provide voice guidance to the user based on the positioning accuracy.

[0054] In this case, when the user specifies a destination and the server device 200 determines a route to the destination, the server device 200 can know which sections on the guide route have high GPS positioning accuracy and which sections have low GPS positioning accuracy by referring to the map data. Therefore, even if the server device 200 does not receive information on the GPS positioning accuracy at the vehicle position of the vehicle Ve from the voice output device 100, it is sufficient for the server device 200 to provide guidance using distance in sections in the map data where the GPS positioning accuracy is high and to provide guidance using landmarks in sections where the GPS positioning accuracy is low.

[0055] (Variation 3) When there are multiple guide points in a place where the GPS positioning accuracy is reduced, such as a long tunnel, the voice output device 100 cannot update the vehicle position in the section, and cannot provide voice guidance on information about each guide point. Therefore, the voice output device 100 may update the vehicle position and provide voice guidance on information about the next guide point by voice operation by the user. For example, when there are multiple guide points in a long tunnel, when the vehicle Ve passes a guide point in the tunnel, the user speaks that the vehicle Ve has passed the guide point, and notifies the voice output device 100. The voice output device 100 updates the vehicle position based on the user's speech, and provides voice guidance on information about the next guide point in the tunnel. This makes it possible for the user to grasp the next guide point even if there are consecutive sections where the GPS positioning accuracy is reduced.

[0056] In the above-described embodiment, the program can be stored using various types of non-transitory computer readable media and can be supplied to a control unit, which is a computer. The non-transitory computer readable medium includes various types of tangible storage media. Examples of the non-transitory computer readable medium include magnetic storage media (e.g., flexible disks, magnetic tapes, hard disk drives), magneto-optical storage media (e.g., magneto-optical disks), CD-ROM (Read Only Memory), CD-R, CD-R / W, and semiconductor memory (e.g., mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)).

[0057] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. In other words, the present invention naturally includes various modifications and corrections that a person skilled in the art could make in accordance with the entire disclosure, including the claims, and the technical ideas. In addition, the disclosures of the above cited patent documents and the like are incorporated herein by reference. [Explanation of symbols]

[0058] 100 Audio output device 200 Server device 111, 211 Communications Department 112, 212 Storage section 113 Input section 114, 214 Control section 115 Sensor Group 116 Display section 117 Mike 118 Speaker 119 Exterior Camera 120 In-car camera

Claims

1. An acquisition unit that acquires the positioning accuracy of a GPS; a voice guidance unit that performs voice guidance using information that does not depend on the position of the moving object when the positioning accuracy is lower than a reference value; Equipped with The voice guidance unit is a voice output device that outputs voice guidance regarding the next guide point when the positioning accuracy is no longer equal to or greater than the reference value.

2. The voice output device according to claim 1 , wherein the voice guidance unit uses information on landmarks at the guidance points.

3. 3 . The audio output device according to claim 1 , wherein the audio guidance unit outputs a message indicating that the positioning accuracy has decreased when the positioning accuracy is no longer equal to or greater than the reference value.

4. The audio output device according to claim 1 , wherein the acquisition unit acquires the positioning accuracy based on map data.

5. An audio output method executed by an audio output device, comprising: An acquisition step of acquiring a positioning accuracy of a GPS; a voice guidance step of providing voice guidance using information that does not depend on the position of the moving object when the positioning accuracy is lower than a reference value; Equipped with The voice guidance step is a voice output method for outputting voice guidance regarding a next guide point when the positioning accuracy is no longer equal to or greater than the reference value.

6. An acquisition means for acquiring the positioning accuracy of the GPS; a voice guidance means for providing voice guidance using information that is not dependent on the position of the moving object when the positioning accuracy is lower than a reference value; The computer functions as The voice guidance means is a program that outputs voice guidance regarding the next guide point when the positioning accuracy is no longer equal to or greater than the reference value.

7. A storage medium storing the program according to claim 6.

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