Patent Publication Number: US-11395096-B2

Title: Information sharing device, information sharing method, and recording medium

Description:
This application is a National Stage Entry of PCT/JP2018/021303 filed on Jun. 4, 2018, the contents of all of which are incorporated herein by reference, in their entirety. 
     TECHNICAL FIELD 
     The present invention relates to an information sharing device, an information sharing method, and a recording medium for sharing sensing information among devices. 
     BACKGROUND ART 
     There has been a trend in which an information acquisition device (sensing device) such as a sensor or a camera is mounted on an unmanned machine and an operation is performed by a plurality of unmanned machines arranged in a specific area. For example, an application is conceivable in which a camera-equipped unmanned machine in a flying form is used to search for and monitor areas that are difficult for humans, such as disaster areas or vast areas. 
     As described above, when an operation is performed by a plurality of unmanned machines, it is desirable that each of the unmanned machines acts efficiently by avoiding overlap between the sensing area of the own machine and the sensing area of another machine as much as possible. For this purpose, it is necessary for each unmanned machine to share sensing information such as position information and sensing results of the unmanned machine with another machine sequentially. For this information sharing, wireless communication is mainly used. 
     However, when wireless communication is used for information sharing, there is a possibility that stable and continuous information sharing among unmanned machines becomes impossible due to interruption of communication caused by limitation of communication range, fluctuation of radio quality due to the environment, and influence of interfering radio waves, or the like. A loss of information from other unmanned machines may then affect the behavior of each unmanned machine, thereby reducing operational efficiency of unmanned machines. 
     On the other hand, PTL 1 to PTL 3 disclose methods for supplementing missing information. 
     In the method disclosed in PTL 1, connection candidate and identification information pairs are generated for a trajectory interrupted in a track range for mobile object, a likelihood for each pair is calculated to identify which trajectory the trajectory is associated with, and the interrupted trajectory is connected. 
     In the method of PTL 2, when presenting a time required for a vehicle to pass through a road section based on probe information collected by the vehicle, a missing section is interpolated based on a correlation coefficient with data of another section which is not missing. 
     In the method described in PTL 3, a main component analysis is performed using past probe information to linearly synthesize information having a strong correlation, and for a missing link, synthesized information of the link is used as complementary information. 
     However, in the methods disclosed in PTL 1 to PTL 3, batch processing is performed off-line based on past data to compensate for loss of data. Therefore, when there is insufficient data in the past or a sudden interruption occurs, each unmanned machine cannot autonomously supplement information. 
     A method of controlling movement of a mobile object while sharing information online is described in PTL 4 and PTL 5. 
     For example, in the method described in PTL 4, a communication status between a mobile terminal device and another mobile terminal device is determined based on the position of the mobile terminal device, the position of the another mobile terminal device, and surrounding geographical conditions, and a destination of the mobile terminal device is determined. 
     In the method described in PTL 5, when radio communication with another mobile object is interrupted, the speed and position of the mobile object after the interruption are predicted based on mobile object information received from the mobile object until the interruption. Then, movement support is performed using the predicted speed and position information. 
     CITATION LIST 
     Patent Literature 
     
         
         [PTL 1] WO 2011/021588 A 
         [PTL 2] WO 2015/059877 A 
         [PTL 3] JP 2008-123145 A 
         [PTL 4] JP 2014-138268 A 
         [PTL 5] WO 2015/151192 A 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     However, in the methods of PTL 4 and PTL 5, when communication is interrupted, sensing information of the mobile object with which the communication is interrupted cannot be received, and thus there is a possibility that accuracy of the sensing information is deteriorated. 
     An object of the present invention is to provide an information sharing device, an information sharing method, and a recording medium that enable to improve accuracy of sensing information after being shared when there is a possibility of loss of sensing information from another device, and to improve efficiency of control based on the sensing information. 
     Solution to Problem 
     In order to solve the above problems, an information sharing device according to the present invention includes an acquisition means for acquiring a sensing result of an own device, a transmission means for transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage means, a reception means for receiving the integrated information of the another device that is communicable, and an integration means for causing the integrated information storage means to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage means of the own device, the sensing result of the own device, and the integrated information of the another device. 
     An information sharing method according to the present invention includes acquiring a sensing result of an own device, transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage, receiving the integrated information of the another device that is communicable, and causing the integrated information storage to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage of the own device, the sensing result of the own device, and the integrated information of the another device. 
     A computer-readable recording medium recording an information sharing program according to the present invention, the information sharing program causing a computer to execute an acquisition function for acquiring a sensing result of an own device, a transmission function for transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage means, a reception function for receiving the integrated information of the another device that is communicable, and an integration function for causing the integrated information storage means to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage means of the own device, the sensing result of the own device, and the integrated information of the another device. 
     Advantageous Effects of Invention 
     With the information sharing device, the information sharing method, and the recording medium of the present invention, it is possible to improve accuracy of sensing information after being shared when there is a possibility of loss of sensing information from another device, and to improve the efficiency of control based on sensing information. 
    
    
     
       BRIEF DESCRIPTION OF DRAWING 
         FIG. 1  shows a diagram showing a configuration example of an information sharing device according to a first example embodiment of the present invention. 
         FIG. 2  shows a diagram showing an operation example of the information sharing device according to the first example embodiment of the present invention. 
         FIG. 3  shows a diagram showing a configuration example of an information sharing device according to a second example embodiment of the present invention. 
         FIG. 4  shows a diagram showing an operation example of the information sharing device according to the second example embodiment of the present invention. 
         FIG. 5  shows a diagram showing an operation example of the information sharing device according to the second example embodiment of the present invention. 
         FIG. 6  shows a diagram showing an operation example of the information sharing device according to the second example embodiment of the present invention. 
         FIG. 7  shows a diagram showing a configuration example of an information sharing device according to a third example embodiment of the present invention. 
         FIG. 8  shows a diagram showing an operation example of an information sharing device according to the third example embodiment of the present invention. 
         FIG. 9  shows a diagram showing an operation example of an information sharing device according to the third example embodiment of the present invention. 
         FIG. 10  shows a diagram showing a hardware configuration example of each example embodiment of the present invention. 
     
    
    
     EXAMPLE EMBODIMENT 
     First Example Embodiment 
     A first example embodiment of the present invention is described. 
       FIG. 1  shows a configuration example of an information sharing device  10  of the present example embodiment. 
     The information sharing device  10  of the present example embodiment includes an acquisition unit  11 , an integrated information storage unit  12 , a transmission unit  13 , a reception unit  14 , and an integration unit  15 . 
     The acquisition unit  11  acquires a sensing result of an own device. The transmission unit  13  transmits integrated information obtained by integrating information related to sensing results of the own device and another device stored in the integrated information storage unit  12 . The reception unit  14  receives integrated information of another device that is communicable. The integration unit  15  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information of the another device. 
     By the information sharing device  10  configured as described above, the information sharing device  10  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  10  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  10 , the information sharing device  10  can receive the integrated information obtained by integrating the sensing result of the another device that is not communicable via another device that is communicable, and can improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     Next,  FIG. 2  shows an example of operation of the information sharing device  10  of the present example embodiment. 
     The acquisition unit  11  acquires a sensing result of the own device (step S 101 ). The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12  (step S 102 ). The reception unit  14  receives integrated information of another device that is communicable (step S 103 ). The integration unit  15  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information of the another device (step S 104 ). 
     By operating as described above, the information sharing device  10  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  10  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of another device to still another device. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information after being shared, and to improve efficiency of control based on the sensing information. 
     As described above, in the first example embodiment of the present invention, the information sharing device  10  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  10  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  10 , the information sharing device  10  can receive the integrated information obtained by integrating the sensing result of the another device that is not communicable via another device that is communicable, and can improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information after being shared, and to improve efficiency of control based on the sensing information. 
     Second Example Embodiment 
     Next, a second example embodiment of the present invention is described. In the present example embodiment, a more specific example of the information sharing device is described. 
     First, a configuration example of an information sharing system of the present example embodiment is described with reference to  FIG. 3 . 
     The information sharing system of the present example embodiment includes one or more information sharing devices  20  and a communication network  50 . The information sharing device  20  is a device mounted on an unmanned machine (for example, a robot that performs autonomous activities in water, land, and air, or the like) for sharing information between the unmanned machines. The communication network  50  is a path for sharing information among the information sharing devices  20 . A method of communication in the communication network  50  is not limited to a specific method. 
     Next, a configuration example of the information sharing device  20  of the present example embodiment is described with reference to  FIG. 3 . An estimation unit  26  and a control unit  27  are added to the configuration example ( FIG. 1 ) of the information sharing device  10  of the first example embodiment. 
     The acquisition unit  11  acquires a sensing result of an own device. The acquisition unit  11  acquires the sensing result from a sensing device provided in the own device, such as a camera, various radars, a sonar, or the like. The acquisition unit  11  converts the acquired sensing result into a form that can be integrated in the integration unit  15 . Information acquired by the acquisition unit  11  here is a sensing result in the sensing area of the own device. 
     The integrated information storage unit  12  stores integrated information obtained by integrating information related to sensing results of the own device and another device. 
     The reception unit  14  receives integrated information of another device that is communicable. In the present example embodiment, the reception unit  14  requests another device for the integrated information of the another device, and receives the integrated information of the another device from the another device. It is assumed that the reception unit  14  of the present example embodiment further receives position information of another device and retains information related to the another device, such as an identifier of the another device, position information of the another device, communication status, and the like. The reception unit  14  can also receive information on the sensing area of another device. The integrated information received by the reception unit  14  is integrated information transmitted by the transmission unit  13  of another device. 
     The estimation unit  26  estimates a sensing result of another device that is not communicable. A method of estimation is described later. 
     The integration unit  15  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information of the another device. A method of integration is described later. In the present example embodiment, the integration unit  15  further integrates an estimation result estimated by the estimation unit  26  with respect to another device that is not communicable. 
     As described above, by the integration unit  15  integrating the sensing result of the own device, the integrated information of the own device, and the integrated information of another device, the integrated information becomes one in which the sensing result of the own device and the sensing result of the another device are integrated. 
     The method of storing the integrated information in the integrated information storage unit  12  is not limited to a specific method. For example, the sensing area may be divided into smaller areas, and the integrated information storage unit  12  may manage a numerical value of the integrated information for every smaller area. As a method of managing the numerical value, a method of managing a scalar value which is a single value is conceivable. For example, it is conceivable that, as a result of managing and sensing a value indicating the degree of danger as a value of the sensing result, a low numerical value is set as the value of the integrated information when there is nothing (it is safe), or conversely, a high numerical value is set as the value of the integrated information when there is an object or the like (it is dangerous). A method that manages vector values that are a plurality of values for every area is also conceivable. 
     When performing integration, with respect to integrated information of the own device, the integration unit  15  updates the integrated information of the own device according to an elapsed time since a previous update of the integrated information of the own device, and then performs integration. A method of updating according to the elapsed time is described later. 
     The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . When transmitting the integrated information of the own device, the transmission unit  13  updates the integrated information of the own device according to the elapsed time since the previous update of the integrated information of the own device, and then transmits the integrated information to another device. In the present example embodiment, when a request is received from another device, the transmission unit  13  transmits the integrated information of the own device to the another device as the request source. 
     As described above, by the transmission unit  13  transmitting the integrated information to another device, the information of the another device can be transmitted to still another device. By the reception unit  14  receiving the integrated information thus transmitted, even when communication with certain another device is interrupted, information of the another device whose communication is interrupted can be obtained from another device that is communicable. 
     The control unit  27  controls arrangement of the own device based on the integrated information stored in the integrated information storage unit  12 . 
     Next, a description is given of a method of updating integrated information of the own device in the integration unit  15  and the transmission unit  13 . 
     The integration unit  15  and the transmission unit  13  update the integrated information of the own device according to an elapsed time since the previous update of the integrated information of the own device performed by the integration unit  15  or the transmission unit  13 . For example, the integration unit  15  or the transmission unit  13  applies a function related to the elapsed time to the integrated information of the own device, to thereby obtain the integrated information that is new of the own device. 
     For example, it is assumed that the integrated information storage unit  12  stores a scalar value for a small area, and the scalar value increases according to a function according to the elapsed time, for example, Formula (1).
 
 f ( t )= F×ginc   t   (1)
 
     Here, t is the elapsed time, f(t) is the scalar value after the time t has elapsed, F is the current scalar value, and ginc is a constant that determines the amount of increase. At this time, the integration unit  15  or the transmission unit  13  can calculate f(t) by applying the above Formula (1) to the scalar value of each small area, to thereby update the scalar value of each small area. Depending on characteristics of the sensing information, it is also possible to use a function that decreases according to the elapsed time, for example, as in Formula (2).
 
 f ( t )= F×e   −λt   (2)
 
     λ is a constant that determines attenuation. 
     As described above, the information sharing device  20  updates the integrated information of the own device according to the elapsed time, and thus when the sensing information changes according to the elapsed time, accuracy of the integrated information can be improved. By updating according to the elapsed time, the integrated information becomes information added with the elapsed time, that is, information added with past information. Therefore, when communication with another device becomes possible from impossible, the information sharing device  20  can obtain integrated information added with past information, that is, integrated information added with information during communication interruption. 
     Next, a description is given of an example of a method of estimating a sensing result of another device that is not communicable in the estimation unit  26 . The estimation method described here is an example, and other estimation methods may be applied to the present example embodiment. 
     For example, the estimation unit  26  can estimate a current position of another device based on position information of the another device received by the reception unit  14  in the past. For example, a method of estimating the current position based on position information (position and velocity) of another device, which is last received from the another device, on the assumption that the another device is moving straight at a fixed speed, is conceivable. 
     The estimation unit  26  can estimate the sensing area of another device, for example, based on performance and characteristics of the sensing device to be used. For example, assuming that the sensing area of another device has a simple shape (for example, a perfect circular shape centered on an estimated position), a method of estimating as the sensing area of the another device a range based on the performance and characteristics of the sensing device is conceivable. 
     The estimation unit  26  can estimate the sensing result for the estimated sensing area, for example, based on the performance of the sensing device used. For example, assuming that a uniform sensing result is obtained in the estimated sensing area, a method of using a uniform value based on the performance of the sensing device as the sensing result is conceivable. 
     As described above, the information sharing device  20  estimates the sensing result of another device that is not communicable and uses the estimated sensing result in place of the integrated information of the another device, and thereby it is possible to improve accuracy of the integrated information of the own device more than in a case where the information is missing. 
     Next, an example of an integration method in the integration unit  15  is described. Integration is a process of combining information related to sensing results of the own device and another device to estimate values that would be more appropriate as a sensing result of the entire system. The integration unit  15  causes the integrated information storage unit  12  to store integrated information obtained by integrating information related to sensing results of the own device and another device. The integration method described here is an example, and another integration method may be applied to the present example embodiment. 
     For example, it is assumed that the integrated information storage unit  12  stores a scalar value for a small area. Then, a method is conceivable in which the integration unit  15  performs integration by calculating a new scalar value for each small area, for example, according to Formula (3). 
     
       
         
           
             
               
                 
                   
                     
                       
                         
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     Here, S 1  is a value of the sensing result of the own device acquired by the acquisition unit  11 . S 2  is a value of the integrated information of the own device stored in the integrated information storage unit  12 . S i  (i=3 to p) is a value of the integrated information of another device received by the reception unit  14 . S j  (j=p+1 to q) is a value of the sensing information of the another device estimated by the estimation unit  26 . m k  is a weighting coefficient for each of the elements (S 1 , S 2 , S i , S j ). (p−2) is the number of pieces of the integrated information of the another device received by the reception unit  14 , and (q−p) is the number of pieces of the integrated information of the another device estimated by the estimation unit  26 . 
     When there is an element for which no value exists for a certain small area, the weighting coefficient m k =0 for the element is set. For example, the value of S 1  does not exist for a small area outside the sensing area of the own device, and thus m 1 =0 is set. When the weighting coefficients m k  for the elements S k  in which values exist are set to the same value, Formula (3) calculates the average value of the elements in which the values exist. 
     It is considered that reliability of the sensing result estimated by the estimation unit  26  decreases according to the elapsed time from communication interruption. Therefore, the integration unit  15  may change a weighting coefficient m j  with respect to a sensing result S j  estimated by the estimation unit  26  according to the elapsed time from the communication interruption. For example, the integration unit  15  may reduce the weighting coefficient m j  with respect to the estimated sensing result S j  according to the elapsed time from communication interruption to reduce a contribution ratio of the estimated sensing result to a calculation result of Formula (3). 
     Instead of using the expression (3), the integration unit  15  may use a minimum value and a maximum value of each element S k  in each small area as a new scalar value. The integration unit  15  may determine a value of the integrated information that is new by an operation based on probability theory. 
     In order to reduce the amount of data shared among the information sharing devices  20 , the transmission unit  13  may compress and transmit the integrated information, and the integrated information received by the reception unit  14  may be decompressed. By the information sharing device  20  compressing and decompressing the integrated information, a used bandwidth of the communication network  50  can be reduced. 
     For example, a reversible compression process (zip or the like) used in a computer or the like can be used for compression and decompression. When values are managed for every small area, a method that uses a compressing method for image data, or the like is also possible. A method of compressing the number of small areas is also possible by a method of dynamically managing the number of small areas, for example, a method of grouping small areas in which the same value continues into one small area, or the like. 
     By the information sharing device  20  configured as described above, the information sharing device  20  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  20  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of the another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  20 , the information sharing device  20  can receive the integrated information obtained by integrating the sensing result of the another device that is not communicable via another device that is communicable, and it is possible to improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     The information sharing device  20  of the present example embodiment updates the integrated information of the own device according to the elapsed time. Therefore, when the sensing result changes according to the elapsed time, accuracy of the integrated information can be improved. When communication with another device becomes possible from impossible, the information sharing device  20  can obtain integrated information added with information during the communication interruption. 
     The information sharing device  20  of the present example embodiment estimates a sensing result of another device that is not communicable and integrates the sensing result with the integrated information. Therefore, accuracy of the integrated information can be improved. 
     Next, an operation example of the information sharing device  20  of the present example embodiment is described with reference to  FIGS. 4 to 6 .  FIG. 5  shows a more specific operation example of step S 202  in  FIG. 4 . 
     First, the integration unit  15  updates the integrated information stored in the integrated information storage unit  12  according to an elapsed time since a previous update (step S 201  of  FIG. 4 ). The update of the integrated information is performed in step S 201  of  FIG. 4  or step S 212  of  FIG. 6 . The reception unit  14  receives integrated information and position information from another device that is communicable (step S 202 ). 
     In step S 202 , the reception unit  14  updates communication propriety information of another device (step S 207  of  FIG. 5 ), and every another device that is communicable (step S 208 ) transmits a request to another device (step S 209 ). Then, integrated information of another device and current position information of the another device are received (step S 210 ). 
     The estimation unit  26  estimates a sensing result of another device that is not communicable (step S 203 ). The acquisition unit  11  acquires a sensing result of the own device (step S 204 ). Steps S 204  to S 201  may be performed in parallel or in a different order. 
     Next, the integration unit  15  stores the integrated information obtained by integrating the sensing result of the own device, the integrated information of the own device, the integrated information of the another device, and the estimated sensing result of the another device in the integrated information storage unit  12  (step S 205 ). Then, the control unit  27  controls an arrangement of the own device based on the integrated information of the integrated information storage unit  12  (step S 206 ). 
     Upon receiving a request from another device (step S 211  in  FIG. 6 ), the reception unit  14  updates the integrated information stored in the integrated information storage unit  12  according to the elapsed time since the previous update (step S 212 ). The integrated information of the own device and the current position information are then transmitted to the another device as the request source (step S 213 ). 
     By operating as described above, the information sharing device  20  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     As described above, in the second example embodiment of the present invention, the information sharing device  20  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  20  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of the another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  20 , the information sharing device  20  can receive the integrated information obtained by integrating the sensing result of the another device that is not communicable via another device that is communicable, and it is possible to improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     The information sharing device  20  of the present example embodiment updates the integrated information of the own device according to the elapsed time. Therefore, when the sensing result changes according to the elapsed time, accuracy of the integrated information can be improved. When communication with another device becomes possible from impossible, the information sharing device  20  can obtain integrated information added with information during the communication interruption. 
     The information sharing device  20  of the present example embodiment estimates a sensing result of another device that is not communicable and integrates the sensing result with the integrated information. Therefore, accuracy of the integrated information can be improved. 
     Third Example Embodiment 
     Next, a third example embodiment of the present invention is described. In the present example embodiment, a configuration in which position information is shared between devices in addition to the integrated information is described. 
     First,  FIG. 7  shows a configuration example of an information sharing device  30  of the present example embodiment. A configuration example of the information sharing device  30  of the present example embodiment is a configuration in which a position-related information storage unit  38  is added to the configuration example ( FIG. 3 ) of the information sharing device  20  of the second example embodiment. 
     An acquisition unit  11 , an integrated information storage unit  12 , an integration unit  15 , and a control unit  27  of the present example embodiment are similar to those of the second example embodiment. 
     The position-related information storage unit  38  stores position-related information regarding each of information sharing devices  30  in the information sharing system. The position-related information includes at least an identifier of an information sharing device  30  and position information of the information sharing device  30 . The position-related information may further include an update time of the position information of the information sharing device  30 , sensing area information of the information sharing device  30 , and the communication propriety information between the own device and another device when the information sharing device  30  is the another device. 
     The reception unit  14  of the present example embodiment receives from another device that is communicable the position-related information stored in the position-related information storage unit  38  of the another device in addition to the integrated information of the another device. When having received the position-related information, the reception unit  14  updates the position-related information in the position-related information storage unit  38  based on the received position-related information. For example, the reception unit  14  compares an update time of the received position-related information with the update time of the position-related information stored in the position-related information storage unit  38 . If the received position-related information includes information whose update time is newer, the position-related information stored in the position-related information storage unit  38  is updated with the information. 
     In addition to the integrated information of the own device, the transmission unit  13  of the present example embodiment transmits the position-related information stored in the position-related information storage unit  38  to another device. 
     When estimating a sensing result of another device that is not communicable, the estimation unit  26  of the present example embodiment estimates the sensing result based on the position-related information stored in the position-related information storage unit  38 . For example, the estimation unit  26  can estimate the current position of the another device by using the position-related information stored in the position-related information storage unit  38  instead of the “position information of another device received in the past” in the second example embodiment. When the position-related information also includes information of sensing areas, for example, the latest sensing area of the another device can be estimated as the current sensing area of the another device. 
     As described above, it is possible to update the position-related information regarding another device that is not communicable with the own device via another device that is communicable with the own device. Consequently, estimation accuracy of the current position of another device can be improved, and therefore, estimation accuracy of the sensing result of the another device in the estimation unit  26  can be improved. 
     By the information sharing device  30  configured as described above, the information sharing device  30  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  30  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  30 , the information sharing device  30  can receive the integrated information obtained by integrating a sensing result of the another device that is not communicable via another device that is communicable, and it is possible to improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     The information sharing device  30  of the present example embodiment receives the position-related information from another device, updates the position-related information stored in the own device based on the received position-related information, and transmits the updated position-related information to the another device. Thus, it is possible to update the position-related information regarding the another device that is not communicable with the own device via another device that is communicable with the own device. Consequently, it is possible to improve estimation accuracy of the sensing result of another device in the estimation unit  26 . 
     Next, an operation example of the information sharing device  30  of the present example embodiment is described with reference to  FIGS. 4, 8, and 9 .  FIG. 8  shows a more specific operation example of step S 202  (integrated information acquisition operation) of  FIG. 4 . 
     A general flow of operation of the information sharing device  30  is similar to that of the operation example of the second example embodiment ( FIG. 4 ). 
     In step S 308  of  FIG. 9 , the transmission unit  13  of the present example embodiment updates the position-related information related to the own device of the position-related information storage unit  38  with the latest position information of the own device. In step S 309  of  FIG. 9 , the transmission unit  13  transmits the position-related information stored in the position-related information storage unit  38  instead of the current position information. 
     In step S 304  of  FIG. 8 , the reception unit  14  of the present example embodiment receives the position-related information stored in the position-related information storage unit  38  of the another device instead of the current position information of the another device. In step S 305  of  FIG. 8 , the reception unit  14  updates the position-related information stored in the position-related information storage unit  38  based on the received position-related information. 
     In step S 203  of  FIG. 4 , the estimation unit  26  estimates the sensing result of the another device that is not communicable based on the position-related information stored in the position-related information storage unit  38 . In the present example embodiment, since the position-related information updated in step S 202  is used in step S 203 , step S 203  needs to be performed between step S 202  and step S 205 . 
     The other operations are similar to those in the second example embodiment, and thus the description thereof is omitted. 
     By operating as described above, the information sharing device  30  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     As described above, in the third example embodiment of the present invention, the information sharing device  30  causes the integrated information storage unit  12  to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage unit  12  of the own device, the sensing result of the own device, and the integrated information received from another device. The transmission unit  13  transmits the integrated information stored in the integrated information storage unit  12 . Thus, the information sharing device  30  can transmit the integrated information obtained by integrating the integrated information of the own device with the sensing result of the own device and the integrated information of another device to still another device. Consequently, even if there is another device that is not communicable with the information sharing device  30 , the information sharing device  30  can receive the integrated information obtained by integrating a sensing result of the another device that is not communicable via another device that is communicable, and it is possible to improve accuracy of the integrated information. Therefore, when there is a possibility of loss of sensing information from another device, it is possible to improve accuracy of sensing information (integrated information) after being shared, and to improve efficiency of control based on the sensing information. 
     The information sharing device  30  of the present example embodiment receives the position-related information from another device, updates the position-related information stored in the own device based on the received position-related information, and transmits the updated position-related information to the another device. Thus, it is possible to update the position-related information regarding the another device that is not communicable with the own device via another device that is communicable with the own device. Consequently, it is possible to improve estimation accuracy of the sensing result of another device in the estimation unit  26 . 
     [Hardware Configuration Example] 
     A configuration example of hardware resources for achieving the information sharing device ( 10 ,  20 ,  30 ) according to each of the example embodiments of the present invention described above by using one information processing device (computer) is described. The information sharing device may be achieved by using at least two information processing devices physically or functionally. The information sharing device may be achieved as a dedicated device. Only a part of the functions of the information sharing device may be achieved by using the information processing device. 
       FIG. 10  is a diagram schematically showing a hardware configuration example of the information processing device capable of achieving the information sharing device of each of the example embodiments of the present invention. The information processing device  90  includes a communication interface  91 , an input-output interface  92 , an arithmetic device  93 , a storage device  94 , a non-transitory storage device  95 , and a drive device  96 . 
     The communication interface  91  is a communication means for the information sharing device of each of the example embodiments to communicate with an external device by wire or/and wireless. In a case where the information sharing device is achieved by using at least two information processing devices, the devices may be connected so as to be able to communicate with each other via the communication interface  91 . 
     The input-output interface  92  is a man-machine interface such as a keyboard as an example of an input device and a display as an output device. 
     The arithmetic device  93  is an arithmetic processing device such as a general-purpose central processing unit (CPU) or a microprocessor. For example, the arithmetic device  93  can read various programs stored in the non-transitory storage device  95  into the storage device  94  and execute processing according to the read programs. 
     The storage device  94  is a memory device such as a random access memory (RAM), which can be referred to from the arithmetic device  93 , and stores programs, various data, and the like. The storage device  94  may be a volatile memory device. 
     The non-transitory storage device  95  is a non-transitory storage device such as a read only memory (ROM), a flash memory, or the like, and can store various programs, data, and the like. 
     The drive device  96  is, for example, a device that reads or writes data to a recording medium  97 , which is described later. 
     The recording medium  97  is, for example, any recording medium capable of recording data, such as an optical disk, a magneto-optical disk, a semiconductor flash memory, or the like. 
     Each of the example embodiments of the present invention may be achieved, for example, by configuring an information sharing device with the information processing device  90  illustrated in  FIG. 10 , and supplying to the information sharing device a program capable of achieving the functions described in each of the example embodiments described above. 
     In this case, the example embodiment can be achieved by executing a program supplied to the information sharing device by the arithmetic device  93 . It is also possible to configure not all but a part of the functions of the information sharing device by the information processing device  90 . 
     The program may be recorded on the recording medium  97 , and the program may be appropriately stored in the non-transitory storage device  95  in a shipping stage, an operating stage, or the like of the information sharing device. In this case, as a method of supplying the program, a method of installing the program in the information sharing device using an appropriate jig may be employed in a manufacturing stage before shipment, an operating stage, or the like. The program may be supplied by a general procedure such as downloading from the outside through a communication line such as the Internet. 
     The whole or part of the example embodiments disclosed above can be described as, but not limited to, the following supplementary notes. 
     (Supplementary Note 1) 
     An information sharing device comprising: 
     an acquisition means for acquiring a sensing result of an own device; 
     a transmission means for transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage means; 
     a reception means for receiving the integrated information of the another device that is communicable; and 
     an integration means for causing the integrated information storage means to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage means of the own device, the sensing result of the own device, and the integrated information of the another device. 
     (Supplementary Note 2) 
     The information sharing device according to supplementary note 1, further comprising 
     a control means for controlling the own device based on the integrated information stored in the integrated information storage means. 
     (Supplementary Note 3) 
     The information sharing device according to supplementary note 1 or 2, wherein 
     the integration means updates the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter integrates the integrated information of the own device. 
     (Supplementary Note 4) 
     The information sharing device according to any one of supplementary notes 1 to 3, wherein 
     the transmission means updates the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter transmits the integrated information of the own device. 
     (Supplementary Note 5) 
     The information sharing device according to any one of supplementary notes 1 to 4, further comprising 
     an estimation means for estimating the sensing result of the another device that is not communicable, 
     wherein the integration means further integrates the sensing result that is estimated of the another device. 
     (Supplementary Note 6) 
     The information sharing device according to supplementary note 5, wherein 
     The reception means further receives position information of the another device, and 
     the estimation means estimates a current position of the another device based on the position information of the another device. 
     (Supplementary Note 7) 
     The information sharing device according to any one of supplementary notes 1 to 6, wherein 
     the reception means further receives position-related information related to a position of the another device and updates the position-related information stored in a position-related information storage means based on the position-related information, and 
     the transmission means further transmits the position-related information stored in the position-related information storage means. 
     (Supplementary Note 8) 
     The information sharing device according to supplementary note 5, wherein 
     the reception means further receives position-related information related to a position of the another device and updates the position-related information stored in a position-related information storage means based on the position-related information, 
     the transmission means further transmits the position-related information stored in the position-related information storage means, and 
     the estimation means estimates a current position of the another device based on the position-related information stored in the position-related information storage means. 
     (Supplementary Note 9) 
     An information sharing method comprising: 
     acquiring a sensing result of an own device; 
     transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage means; 
     receiving the integrated information of the another device that is communicable; and 
     causing the integrated information storage means to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage means of the own device, the sensing result of the own device, and the integrated information of the another device. 
     (Supplementary Note 10) 
     The information sharing method according to supplementary note 9, further comprising 
     controlling the own device based on the integrated information stored in the integrated information storage means. 
     (Supplementary Note 11) 
     The information sharing method according to supplementary note 9 or 10, further comprising 
     updating the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter integrating the integrated information of the own device. 
     (Supplementary Note 12) 
     The information sharing method according to any one of supplementary notes 9 to 11, further comprising 
     updating the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter transmitting the integrated information of the own device. 
     (Supplementary Note 13) 
     The information sharing method according to any one of supplementary notes 9 to 12, further comprising: 
     estimating the sensing result of the another device that is not communicable; and 
     further integrating the sensing result that is estimated of the another device. 
     (Supplementary Note 14) 
     The information sharing method according to supplementary note 13, further comprising: 
     receiving position information of the another device; and 
     estimating a current position of the another device based on the position information of the another device. 
     (Supplementary Note 15) 
     The information sharing method according to any one of supplementary notes 9 to 14, further comprising: 
     receiving position-related information related to a position of the another device and updating the position-related information stored in a position-related information storage means based on the position-related information; and 
     transmitting the position-related information stored in the position-related information storage means. 
     (Supplementary Note 16) 
     The information sharing method according to supplementary note 13, further comprising: 
     receiving position-related information related to a position of the another device and updating the position-related information stored in a position-related information storage means based on the position-related information; 
     transmitting the position-related information stored in the position-related information storage means; and 
     estimating a current position of the another device based on the position-related information stored in the position-related information storage means. 
     (Supplementary Note 17) 
     A computer-readable recording medium recording an information sharing program, the information sharing program causing a computer to execute: 
     an acquisition function for acquiring a sensing result of an own device; 
     a transmission function for transmitting integrated information obtained by integrating information related to the sensing result of the own device and another device stored in an integrated information storage means; 
     a reception function for receiving the integrated information of the another device that is communicable; and 
     an integration function for causing the integrated information storage means to store the integrated information that is new obtained by integrating the integrated information stored in the integrated information storage means of the own device, the sensing result of the own device, and the integrated information of the another device. 
     (Supplementary Note 18) 
     The computer-readable recording medium recording the information sharing program according to supplementary note 17, the information sharing program causing the computer to further execute 
     a control function for controlling the own device based on the integrated information stored in the integrated information storage means. 
     (Supplementary Note 19) 
     The computer-readable recording medium recording the information sharing program according to supplementary note 17 or 18, wherein 
     the integration function updates the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter integrates the integrated information of the own device. 
     (Supplementary Note 20) 
     The computer-readable recording medium recording the information sharing program according to any one of supplementary notes 17 to 19, wherein 
     the transmission function updates the integrated information of the own device according to an elapsed time since a time of a previous update of the integrated information of the own device, and thereafter transmits the integrated information of the own device. 
     (Supplementary Note 21) 
     The computer-readable recording medium recording the information sharing program according to any one of supplementary notes 17 to 20, the information sharing program causing the computer to further execute 
     an estimation function for estimating the sensing result of the another device that is not communicable, 
     wherein the integration function further integrates the sensing result that is estimated of the another device. 
     (Supplementary Note 22) 
     The computer-readable recording medium recording the information sharing program according to supplementary note 21, wherein 
     the reception function further receives position information of the another device, and 
     the estimation function estimates a current position of the another device based on the position information of the another device. 
     (Supplementary Note 23) 
     The computer-readable recording medium recording the information sharing program according to any one of supplementary notes 17 to 22, wherein 
     the reception function further receives position-related information related to a position of the another device and updates the position-related information stored in a position-related information storage means based on the position-related information, and 
     the transmission function further transmits the position-related information stored in the position-related information storage means. 
     (Supplementary Note 24) 
     The computer-readable recording medium recording the information sharing program according to supplementary note 21, wherein 
     the reception function further receives position-related information related to a position of the another device and updates the position-related information stored in a position-related information storage means based on the position-related information, 
     the transmission function further transmits the position-related information stored in the position-related information storage means, and 
     the estimation function estimates a current position of the another device based on the position-related information stored in the position-related information storage means. 
     While the invention has been particularly shown and described with reference to exemplary embodiments thereof, the invention is not limited to these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims. 
     REFERENCE SIGNS LIST 
     
         
           10 ,  20 ,  30  Information sharing device 
           11  Acquisition unit 
           12  Integrated information storage unit 
           13  Transmission unit 
           14  Reception unit 
           15  Integration unit 
           26  Estimation unit 
           27  Control unit 
           38  Position-related information storage unit 
           90  Information processing device 
           91  Communication interface 
           92  Input-output interface 
           93  Arithmetic device 
           94  Storage device 
           95  Non-transitory storage device 
           96  Drive device 
           97  Recording medium