Travel distance calculation device and travel distance calculation method

Abstract

A travel distance calculation device (1) comprises: a detection unit (10) that detects the travel distance of a mobile body (2) using a sensor in which the average error rate of errors included in a detection value is a first error rate; a storage unit (20) that stores the integrated travel distance of the mobile body (2) from a defined position based on the travel distance of the mobile body (2) detected by the detection unit (10); and a correction unit (30) that corrects the integrated travel distance by multiplying the integrated travel distance stored in the storage unit (20) by a second error rate made to vary so as to converge to the first error rate as the integrated travel distance increases.

Description

[Technical Field]

[0001] The present disclosure relates to a travel distance calculation device and a travel distance calculation method for calculating the travel distance of a moving object. [Background technology]

[0002] Conventionally, in a mobile object or the like, errors are included when calculating the traveled distance, and therefore the calculated traveled distance is corrected taking into account the expected errors. For example, Patent Document 1 discloses a technology in which a vehicle positioning system compares the actual measured distance between multiple position markers installed on the road with the accumulated traveled distance calculated from the vehicle speed pulse, calculates an error rate from the comparison result, and corrects the accumulated traveled distance using the calculated error rate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-163782 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology assumes a constant error rate, and therefore, the longer the travel distance of the vehicle, i.e., the longer the travel distance of the moving object, the greater the amount of correction to the cumulative travel distance, which can result in a large difference between the actual travel distance and the corrected cumulative travel distance.

[0005] The present disclosure has been made in view of the above, and has an object to provide a running distance calculation device that can improve the accuracy of calculating the running distance of a moving object. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the travel distance calculation device of the present disclosure includes a detection unit that detects the travel distance of a moving object using a sensor in which an average error rate of errors included in detected values ​​is a first error rate, and a calculation unit that calculates a travel distance based on the travel distance of the moving object detected by the detection unit. Accumulation The device is characterized by comprising a memory unit that stores the accumulated mileage, and a correction unit that corrects the accumulated mileage by multiplying the accumulated mileage stored in the memory unit by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage becomes longer. [Effects of the Invention]

[0007] The traveling distance calculation device of the present disclosure has an effect of being able to improve the accuracy of calculating the traveling distance of a moving object. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a configuration example of a travel distance calculation device according to an embodiment. [Figure 2] FIG. 1 is a first block diagram showing an example of the configuration of a detection unit included in a running distance calculation device according to an embodiment; [Figure 3] FIG. 2 is a second block diagram showing an example of the configuration of a detection unit included in the mileage calculation device according to the embodiment; [Figure 4] FIG. 10 is a diagram showing an example of an output error distribution of a sensor used in a detection unit included in a traveling distance calculation device according to an embodiment. [Figure 5] FIG. 10 is a diagram showing an example of an error rate employed by a correction unit included in the traveling distance calculation device according to the embodiment; [Figure 6] FIG. 10 is a diagram showing an example of a range of a position of a moving object when a correction unit included in the traveling distance calculation device according to the embodiment corrects an accumulated traveling distance of the moving object; [Figure 7] 1 is a flowchart showing the operation of a running distance calculation device according to an embodiment; [Figure 8] FIG. 1 is a diagram showing an example in which a processing circuit included in a traveling distance calculation device according to an embodiment is configured with a processor and a memory. [Figure 9]FIG. 1 is a diagram showing an example in which a processing circuit included in a traveling distance calculation device according to an embodiment is configured with dedicated hardware. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a traveling distance calculation device and a traveling distance calculation method according to embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0010] Embodiment FIG. 1 is a block diagram showing an example of the configuration of a mileage calculation device 1 according to this embodiment. The mileage calculation device 1 is mounted on a moving object 2 and calculates the mileage of the moving object 2. The moving object 2 is assumed to be, for example, a train, but the invention is also applicable to cars and the like. When the moving object 2 is a train, the mileage calculation device 1 is used in, for example, CBTC (Communications Based Train Control), ATS (Automatic Train Stop), ATO (Automatic Train Operation), etc., but may also be used in other systems, devices, etc.

[0011] The configuration and operation of the mileage calculation device 1 will be described. As shown in FIG. 1, the mileage calculation device 1 includes a detection unit 10, a storage unit 20, and a correction unit 30. The detection unit 10 detects the mileage of the moving object 2 using a sensor whose detected value has an average error rate equal to a first error rate. The storage unit 20 stores the accumulated mileage of the moving object 2 from a specified position based on the mileage of the moving object 2 detected by the detection unit 10. The correction unit 30 corrects the accumulated mileage by multiplying the accumulated mileage stored in the storage unit 20 by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage increases. When correcting the leading position and the trailing position separately, the correction unit 30 corrects the accumulated mileage of the moving object 2 by extending the leading position of the moving object 2 in the moving direction of the moving object 2 and extending the trailing position of the moving object 2 in the opposite direction to the moving direction. Depending on the purpose, use, etc., the correction unit 30 can correct only the front position of the moving body 2 so that it extends in the direction of travel of the moving body 2, or can correct only the rear position of the moving body 2 so that it extends in the opposite direction to the direction of travel.

[0012] The sensors used in the detection unit 10 include, for example, a speed sensor, a traveled distance detection sensor, etc. The internal configuration of the detection unit 10 differs depending on the sensor used.

[0013] FIG. 2 is a first block diagram showing a configuration example of the detection unit 10 included in the mileage calculation device 1 according to this embodiment. In the example of FIG. 2, the detection unit 10 includes a speed sensor 11, a calculation unit 12, and an update unit 13. The speed sensor 11 detects the traveling speed of the moving object 2. The speed sensor 11 is a speed sensor that can directly detect the speed of the moving object 2, regardless of the wheel diameter of a train or the tire diameter of a car, which is the moving object 2. The calculation unit 12 calculates the traveling distance of the moving object 2 for a specified period using the traveling speed detected by the speed sensor 11. The calculation unit 12 can calculate the traveling distance of the moving object 2 for a specified period by multiplying the average value of the traveling speed detected by the speed sensor 11 for the specified period by the specified period. The update unit 13 updates the accumulated traveling distance stored in the storage unit 20 by adding the traveling distance calculated by the calculation unit 12 to the accumulated traveling distance stored in the storage unit 20 for each specified period.

[0014] Fig. 3 is a second block diagram showing an example of the configuration of detection unit 10 included in mileage calculation device 1 according to this embodiment. In the example of Fig. 3, detection unit 10 includes mileage detection sensor 14 and update unit 15. mileage detection sensor 14 is a sensor that can directly detect the mileage of mobile object 2. Update unit 15 updates the accumulated mileage stored in memory unit 20 at a specified cycle, using the mileage detected by mileage detection sensor 14 as the accumulated mileage.

[0015] In this embodiment, the operation of the detection unit 10 may be a conventional general operation, and therefore, hereinafter, the operation of detecting the travel distance of the moving object 2 will be mainly described with reference to the detection unit 10. Note that the detection unit 10 only needs to be able to detect the travel distance of the moving object 2, and therefore may have a configuration other than that shown in Figs. 2 and 3 as long as it can detect the travel distance of the moving object 2 using sensors other than the speed sensor 11 and the travel distance detection sensor 14.

[0016] Next, a method for the correction unit 30 in the mileage calculation device 1 to correct the accumulated mileage stored in the memory unit 20 will be described. In this embodiment, when correcting the accumulated mileage stored in the memory unit 20, the correction unit 30 multiplies the accumulated mileage by an error rate as in the conventional method. However, the error rate used here is different from the error rate used in the conventional method. Generally, when calculating the position of a moving object 2, such as a train, a margin is added to the train's position, taking into account detection errors of the sensors used. Specifically, by extending the front position of the train in the direction of travel to provide a margin, a situation in which the timing of braking by the train is delayed can be avoided. By extending the rear position of the train in the opposite direction to the direction of travel to provide a margin, a situation in which the following train shortens the inter-vehicle distance when maintaining an appropriate inter-vehicle distance from the preceding train can be avoided. However, as described in the problem to be solved by the present invention, in the method of correcting the accumulated mileage by multiplying the calculated accumulated mileage by a certain error rate, the difference between the actual mileage of the train and the corrected accumulated mileage increases as the train's mileage increases.

[0017] Therefore, in this embodiment, the correction unit 30 varies the error rate used to correct the accumulated travel distance so that a large error rate is used when the accumulated travel distance of the moving object 2 is short, and a small error rate is used depending on the accumulated travel distance of the moving object 2, that is, the error rate is decreased as the accumulated travel distance of the moving object 2 increases. The correction unit 30 corrects the accumulated travel distance using a second error rate that corresponds to the variation in errors contained in the detection values ​​detected by the sensors used in the detection unit 10.

[0018] FIG. 4 is a diagram showing an example of an output error distribution of a sensor used in the detection unit 10 included in the mileage calculation device 1 according to this embodiment. In FIG. 4, the horizontal axis represents the error rate, and the vertical axis represents the frequency of occurrence. That is, FIG. 4 is a histogram showing the frequency of occurrence of sensor errors. The sensor used in the detection unit 10 may be the speed sensor 11 or the mileage detection sensor 14, as described above. The errors contained in the detected values ​​of the sensor of the detection unit 10 are expected to have a certain degree of variability. Regarding the errors contained in the detected values ​​of the sensor of the detection unit 10, when the number of detections is small, i.e., when the traveling distance of the moving object 2 is short, it is necessary to assume that the error will be large, taking into account the base of the output error distribution shown in FIG. 4, so that the corrected position of the moving object 2 is corrected to the safe side. However, when the number of detections is large, i.e., when the traveling distance of the moving object 2 is long, it is expected that errors will occur with similar frequency and absolute value on the right (positive side) and left (negative side) of the output error distribution shown in FIG. 4. As a result, it is expected that the errors on the positive side and the errors on the negative side will cancel each other out. Therefore, when the average value μ of the errors contained in the detection values ​​of the sensor of the detection unit 10 becomes 0 as shown in Figure 4, the correction unit 30 adopts an error rate that becomes smaller as the traveling distance of the moving body 2 becomes longer, i.e., converges to 0.

[0019] FIG. 5 is a diagram showing an example of an error rate employed by the correction unit 30 included in the mileage calculation device 1 according to this embodiment. In FIG. 5, the horizontal axis represents the accumulated mileage of the moving object 2, and the vertical axis represents the error rate employed by the correction unit 30. The correction unit 30 may vary the method of varying the error rate employed depending on the sensor output error distribution shown in FIG. 4. For example, the correction unit 30 increases the error rate initially employed as the base of the sensor output error distribution shown in FIG. 4 increases, and decreases the error rate initially employed as the base of the sensor output error distribution shown in FIG. 4 decreases. Furthermore, the steeper the sensor output error distribution shown in FIG. 4, the shorter the traveling distance of the moving object 2 becomes, so the correction unit 30 adopts an error rate closer to the average value μ of the sensor output error (in the example shown in FIG. 4, 0) from the time when the base of the sensor output error distribution is shorter. In this way, the correction unit 30 varies the error rate employed depending on the shape of the base, such as the width and steepness of the base, i.e., the variance, of the sensor output error distribution used in the detection unit 10.

[0020] 5, the error rate employed by the correction unit 30 with respect to the accumulated mileage has a curved characteristic, but this is merely an example and is not limiting. The correction unit 30 may vary the employed error rate with respect to the accumulated mileage with a characteristic like a line graph, or may vary with a step-like characteristic in which the error rate decreases stepwise with respect to the accumulated mileage. However, if the characteristic of the error rate employed by the correction unit 30 with respect to the accumulated mileage is a step-like characteristic, when a value obtained by correcting the accumulated mileage at a certain point in time is compared with a value obtained by correcting the accumulated mileage next time, it is possible that the value obtained by correcting the accumulated mileage next time will be smaller. Therefore, if the second accumulated mileage acquired from the memory unit 20 after the first accumulated mileage acquired from the memory unit 20 is greater than the first accumulated mileage, and the second corrected accumulated mileage after correcting the second accumulated mileage is smaller than the first corrected accumulated mileage after correcting the first accumulated mileage, the correction unit 30 may adopt the first corrected accumulated mileage or a value obtained by increasing the first corrected accumulated mileage by a specified rate as the corrected value of the second accumulated mileage.

[0021] In this embodiment, the error rate employed by the correction unit 30 may be determined based on a table or the like that is prepared in advance before the operation of the mobile unit 2, the table indicating the relationship between the accumulated travel distance of the mobile unit 2 and the error rate employed for each accumulated travel distance. The table indicating the relationship between the accumulated travel distance of the mobile unit 2 and the error rate employed for each accumulated travel distance may be prepared, for example, by the manufacturer of the mobile unit 2 or the manufacturer of the travel distance calculation device 1, who conducts a travel test of the mobile unit 2 with the travel distance calculation device 1 mounted on the mobile unit 2, and based on the difference between the actual travel distance of the mobile unit 2 and the travel distance of the mobile unit 2 detected by the detection unit 10. The table indicating the relationship between the accumulated travel distance of the mobile unit 2 and the error rate employed for each accumulated travel distance may be different depending on the type of mobile unit 2, or, if the mobile unit 2 is a train, the table may be different depending on the route on which the train operates. The table showing the relationship between the accumulated travel distance of the moving body 2 and the error rate used for each accumulated travel distance may be held by the correction unit 30, or may be stored in the memory unit 20, and the correction unit 30 may refer to the table stored in the memory unit 20 when correcting the accumulated travel distance.

[0022] In the example of FIG. 4 , the output error distribution of the sensor used in the detection unit 10 has a mean value μ of 0 and an error variation shaped like a normal distribution, but is not limited thereto. The output error distribution of the sensor used in the detection unit 10 does not have to have a mean value μ of 0, and the error variation does not have to have a shape like a normal distribution. The manufacturer of the moving object 2, the manufacturer of the mileage calculation device 1, etc., can create a table showing the relationship between the accumulated mileage of the moving object 2 and the error rate used for each accumulated mileage, based on the output error distribution of the sensor used in the detection unit 10 obtained by, for example, a driving test of the moving object 2. However, considering the effort required by the manufacturer of the moving object 2, the manufacturer of the mileage calculation device 1, etc., to create a table showing the relationship between the accumulated mileage of the moving object 2 and the error rate used for each accumulated mileage, and the calculation load required by the correction unit 30 when correcting the accumulated mileage, it is preferable that the error variation included in the detection value detected by the sensor used in the detection unit 10 be represented by a normal distribution and that the first error rate be within a specified range including 0.

[0023] FIG. 6 is a diagram illustrating an example of the range of the position of the moving object 2 when the correction unit 30 included in the mileage calculation device 1 according to this embodiment corrects the accumulated mileage of the moving object 2. Generally, errors in the accumulated mileage occur both on the positive and negative sides. Therefore, when correcting the accumulated mileage of the moving object 2, the correction unit 30 corrects the leading position of the moving object 2 to a position extended in the direction of travel, taking into account the case where the mileage of the moving object 2 is longer than the detected accumulated mileage. Furthermore, the correction unit 30 corrects the tail position of the moving object 2 to a position extended in the direction opposite to the direction of travel, taking into account the case where the mileage of the moving object 2 is shorter than the detected accumulated mileage. In the example of FIG. 6, the correction amount for the leading position of the moving object 2 and the correction amount for the tail position of the moving object 2 are the same, but this is not limiting. The method of correcting the accumulated mileage of the moving object 2 illustrated in FIG. 6 assumes that the variation in errors contained in the detection values ​​detected by the sensor used in the detection unit 10 is expressed by a normal distribution and the first error rate is 0, as shown in FIG. 4. Therefore, when correcting the cumulative travel distance of the moving body 2, the correction unit 30 may correct the leading position of the moving body 2 to extend in the direction of travel of the moving body 2, and may correct the trailing position of the moving body 2 to extend in the opposite direction to the direction of travel of the moving body 2, depending on the error variation contained in the detection value detected by the sensor used in the detection unit 10 and the first error rate.

[0024] For example, when the first error rate is not 0 but on the positive side in the example of FIG. 4, the correction unit 30 makes the correction amount for the rear position of the moving body 2 larger than the correction amount for the leading position of the moving body 2, and when the first error rate is not 0 but on the negative side in the example of FIG. 4, the correction unit 30 makes the correction amount for the rear position of the moving body 2 smaller than the correction amount for the leading position of the moving body 2. This allows the correction unit 30 to perform correction according to errors generated in the sensors used in the detection unit 10. Note that when the correction amount for the leading position of the moving body 2 differs from the correction amount for the trailing position of the moving body 2, the manufacturer of the traveling distance calculation device 1 or the like will create a table showing the relationship between the accumulated traveling distance of the moving body 2, the error rate for correcting the leading position of the moving body 2, and the error rate for correcting the trailing position of the moving body 2.

[0025] Furthermore, when determining the error rate to be adopted, the correction unit 30 may determine the error rate to be adopted based on the previously corrected accumulated mileage, rather than the accumulated mileage stored in the storage unit 20. In this case, the manufacturer of the moving object 2, the manufacturer of the mileage calculation device 1, etc. may create the above-mentioned table on the premise that the correction unit 30 will determine the error rate to be adopted based on the corrected accumulated mileage.

[0026] Furthermore, when there are multiple mobile bodies 2 of the same type equipped with mileage calculation devices 1, the second error rate used by correction unit 30 of mileage calculation devices 1 equipped in each of the same type of mobile bodies 2 may be set commonly for each type of mobile body 2, or may be set individually for each mobile body 2 according to the characteristics of the sensor used in detection unit 10 when installed in each mobile body 2. In the former case, the manufacturer of the mobile body 2, the manufacturer of the mileage calculation device 1, etc., conducts driving tests with multiple mobile bodies 2 and creates a table showing the relationship between the accumulated mileage of the mobile body 2 and the error rate used for each accumulated mileage, taking into account the frequency of errors in the mileage calculation devices 1 equipped in each mobile body 2. In the latter case, the manufacturer of the mobile body 2, the manufacturer of the mileage calculation device 1, etc., conducts driving tests for each mobile body 2, and for each mileage calculation device 1 installed in the mobile body 2, creates a table showing the relationship between the accumulated mileage of the mobile body 2 and the error rate used for each accumulated mileage, taking into account the frequency of errors in the mileage calculation device 1, for each mobile body 2.

[0027] 7 is a flowchart showing the operation of mileage calculation device 1 according to this embodiment. In mileage calculation device 1, detection unit 10 detects the mileage of moving object 2 (step S1). If detection unit 10 is equipped with speed sensor 11, it updates the accumulated mileage stored in storage unit 20 by adding the mileage determined by calculation to the accumulated mileage stored in storage unit 20. If detection unit 10 is equipped with mileage detection sensor 14, it updates the accumulated mileage stored in storage unit 20 by using the mileage detected by mileage detection sensor 14 as the accumulated mileage (step S2). Correction unit 30 corrects the accumulated mileage by multiplying the accumulated mileage stored in storage unit 20 by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage increases (step S3).

[0028] Next, a hardware configuration of the mileage calculation device 1 will be described. In the mileage calculation device 1, the sensors included in the detection unit 10 are sensors such as a speed sensor 11 and a mileage detection sensor 14. The storage unit 20 is a memory. The components other than the sensors included in the detection unit 10 and the correction unit 30 are realized by a processing circuit. The processing circuit may be a processor and memory that executes a program stored in a memory, or may be dedicated hardware.

[0029] FIG. 8 is a diagram showing an example in which the processing circuit 90 included in the mileage calculation device 1 according to this embodiment is configured with a processor 91 and a memory 92. When the processing circuit 90 is configured with the processor 91 and the memory 92, each function of the processing circuit 90 of the mileage calculation device 1 is realized by software, firmware, or a combination of software and firmware. The software or firmware is written as a program and stored in the memory 92. The processing circuit 90 realizes each function by having the processor 91 read and execute the program stored in the memory 92. That is, the processing circuit 90 includes the memory 92 for storing the program that results in the processing of the mileage calculation device 1 being executed. It can also be said that these programs cause a computer to execute the procedures and methods of the mileage calculation device 1.

[0030] The above program can also be said to be a program that causes the mileage calculation device 1 to execute the following steps: a detection step in which the detection unit 10 detects the traveled distance of the moving body 2 using a sensor whose detected value has an average error rate of a first error rate; and a correction step in which the correction unit 30 corrects the accumulated traveled distance by multiplying the accumulated traveled distance stored in the memory unit 20, which stores the accumulated traveled distance of the moving body 2 from a specified position based on the traveled distance of the moving body 2 detected by the detection unit 10, by a second error rate that is varied so that the longer the accumulated traveled distance, the more the error rate converges to the first error rate.

[0031] Here, the processor 91 may be a CPU (Central Processing Unit), a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor), etc. Furthermore, the memory 92 may be, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable ROM), or an EEPROM (registered trademark) (Electrically EPROM), a magnetic disk, a flexible disk, an optical disk, a compact disk, a minidisk, or a DVD (Digital Versatile Disc).

[0032] 9 is a diagram showing an example in which the processing circuit 93 included in the mileage calculation device 1 according to this embodiment is configured with dedicated hardware. When the processing circuit 93 is configured with dedicated hardware, the processing circuit 93 shown in FIG. 9 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. Each function of the mileage calculation device 1 may be realized by the processing circuit 93 individually, or all functions may be realized by the processing circuit 93 together.

[0033] It should be noted that some of the functions of the mileage calculation device 1 may be realized by dedicated hardware and some by software or firmware. In this way, the processing circuit can realize each of the above-mentioned functions by dedicated hardware, software, firmware, or a combination of these.

[0034] As described above, according to this embodiment, in mileage calculation device 1, detection unit 10 detects the mileage of moving object 2 using a sensor in which the average error rate of errors included in the detection value is a first error rate, and correction unit 30 corrects the accumulated mileage by multiplying the accumulated mileage by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage increases. In other words, correction unit 30 corrects the accumulated mileage using a smaller error rate as the accumulated mileage increases. This enables mileage calculation device 1 to improve the accuracy of calculating the mileage of moving object 2.

[0035] In the present embodiment, the description has been given assuming that the mileage calculation device 1 is mounted on the moving object 2, but the present invention is not limited to this. It is also possible to mount only the detection unit 10 of the mileage calculation device 1 on the moving object 2, and install the storage unit 20 and the correction unit 30 outside the moving object 2, for example, in ground equipment. It is also possible to mount only the speed sensor 11 or the mileage detection sensor 14 on the moving object 2, and install the other components outside the moving object 2, for example, in ground equipment. In either case, the mileage calculation device 1 further includes a communication unit (not shown) that is capable of communicating between the moving object 2 and the ground equipment.

[0036] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, and parts of the configurations may be omitted or modified without departing from the spirit of the invention. Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) a detection unit that detects a travel distance of a mobile object using a sensor whose detected value has an average error rate of a first error rate; a storage unit configured to store an accumulated travel distance of the moving object from a specified position based on the travel distance of the moving object detected by the detection unit; a correction unit that corrects the accumulated mileage by multiplying the accumulated mileage stored in the storage unit by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage becomes longer; A traveling distance calculation device comprising: (Appendix 2) The detection unit a speed sensor that detects the traveling speed of the moving object; a calculation unit that calculates a travel distance of the moving object in a specified period of time using the travel speed detected by the speed sensor; an update unit that updates the accumulated mileage stored in the storage unit by adding the mileage calculated by the calculation unit to the accumulated mileage stored in the storage unit for each of the specified periods; 2. The traveling distance calculation device according to claim 1, comprising: (Appendix 3) The detection unit a travel distance detection sensor capable of directly detecting a travel distance of the moving body; an updating unit that updates the accumulated mileage stored in the storage unit at a specified cycle by using the mileage detected by the mileage detection sensor as the accumulated mileage; 2. The traveling distance calculation device according to claim 1, comprising: (Appendix 4) the correction unit corrects the cumulative traveling distance using the second error rate according to the variation in the error included in the detection value detected by the sensor. 4. The traveling distance calculation device according to claim 1, wherein: (Appendix 5) The variation of the error included in the detection value detected by the sensor is expressed by a normal distribution, and the first error rate is within a specified range including 0. 5. The traveling distance calculation device according to claim 4, (Appendix 6) when correcting the accumulated travel distance of the moving body, the correction unit corrects the leading position of the moving body so as to extend it in the direction of travel of the moving body and corrects the trailing position of the moving body so as to extend it in the direction opposite to the direction of travel of the moving body, in accordance with the variation in the error included in the detection value detected by the sensor and the first error rate. 6. The traveling distance calculation device according to any one of appendices 1 to 5. (Appendix 7) When a second accumulated mileage acquired from the storage unit after a first accumulated mileage acquired from the storage unit is greater than the first accumulated mileage and the second corrected accumulated mileage after correcting the second accumulated mileage is smaller than the first corrected accumulated mileage after correcting the first accumulated mileage, the correction unit adopts the first corrected accumulated mileage or a value obtained by increasing the first corrected accumulated mileage by a specified rate as a corrected value of the second accumulated mileage. 7. The traveling distance calculation device according to any one of appendices 1 to 6. (Appendix 8) When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the running distance calculation device mounted on each moving body of the same type is set in common depending on the type of the moving body; 8. The traveling distance calculation device according to any one of appendices 1 to 7, (Appendix 9) When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the mileage calculation device mounted on each of the same type of moving bodies is set individually for each of the moving bodies according to the characteristics of the sensor when the sensor is installed on each of the moving bodies; 8. The traveling distance calculation device according to any one of appendices 1 to 7, (Appendix 10) A mileage calculation method for a mileage calculation device, comprising: a detection step in which a detection unit detects a travel distance of the mobile object using a sensor having an average error rate of errors included in detection values ​​that is a first error rate; a correction step in which a correction unit corrects the accumulated travel distance by multiplying the accumulated travel distance stored in a storage unit that stores an accumulated travel distance of the moving body from a specified position based on the travel distance of the moving body detected by the detection unit by a second error rate that is varied so as to converge to the first error rate as the accumulated travel distance becomes longer; A traveled distance calculation method comprising: (Appendix 11) The detecting step a speed detection step in which a speed sensor detects a traveling speed of the moving object; a calculation step in which a calculation unit calculates a travel distance of the mobile object in a specified period using the travel speed detected by the speed sensor; an updating step in which an updating unit updates the accumulated mileage stored in the storage unit by adding the mileage calculated by the calculation unit to the accumulated mileage stored in the storage unit for each of the specified periods; 11. The mileage calculation method according to claim 10, comprising: (Appendix 12) The detecting step a travel distance detection step in which the travel distance detection sensor directly detects the travel distance of the moving object; an updating step in which an updating unit updates the accumulated mileage stored in the storage unit at a specified cycle by using the mileage detected by the mileage detection sensor as the accumulated mileage; 11. The mileage calculation method according to claim 10, comprising: (Appendix 13) In the correcting step, the corrector corrects the cumulative traveling distance by using the second error rate corresponding to a variation in the error included in the detection value detected by the sensor. 13. The travel distance calculation method according to any one of appendices 10 to 12. (Appendix 14) The variation of the error included in the detection value detected by the sensor is expressed by a normal distribution, and the first error rate is within a specified range including 0. 14. The travel distance calculation method according to claim 13. (Appendix 15) In the correction step, when correcting the accumulated travel distance of the moving body, the correction unit corrects the leading position of the moving body so as to be extended in the direction of travel of the moving body and corrects the trailing position of the moving body so as to be extended in the direction opposite to the direction of travel, in accordance with the variation in the error included in the detection value detected by the sensor and the first error rate. 15. The travel distance calculation method according to any one of appendices 10 to 14. (Appendix 16) In the correction step, when a second accumulated mileage acquired from the memory unit after a first accumulated mileage acquired from the memory unit is greater than the first accumulated mileage and the second corrected accumulated mileage after correcting the second accumulated mileage is smaller than the first corrected accumulated mileage after correcting the first accumulated mileage, the correction unit adopts the first corrected accumulated mileage or a value obtained by increasing the first corrected accumulated mileage by a specified rate as a corrected value of the second accumulated mileage. 16. The travel distance calculation method according to any one of appendices 10 to 15. (Appendix 17) When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the running distance calculation device mounted on each moving body of the same type is set in common depending on the type of the moving body; 17. The travel distance calculation method according to any one of appendices 10 to 16. (Appendix 18) When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the mileage calculation device mounted on each of the same type of moving bodies is set individually for each of the moving bodies according to the characteristics of the sensor when the sensor is installed on each of the moving bodies; 17. The travel distance calculation method according to any one of appendices 10 to 16. [Explanation of symbols]

[0037] 1 Travel distance calculation device, 2 Moving object, 10 Detection unit, 11 Speed ​​sensor, 12 Calculation unit, 13, 15 Update unit, 14 Travel distance detection sensor, 20 Storage unit, 30 Correction unit, 90, 93 Processing circuit, 91 Processor, 92 Memory.

Claims

1. a detection unit that detects a travel distance of a mobile object using a sensor whose detected value has an average error rate of a first error rate; a storage unit that stores an accumulated travel distance based on the travel distance of the moving object detected by the detection unit; a correction unit that corrects the accumulated mileage by multiplying the accumulated mileage stored in the storage unit by a second error rate that is varied so as to converge to the first error rate as the accumulated mileage becomes longer; A traveling distance calculation device comprising:

2. The detection unit a speed sensor that detects the traveling speed of the moving object; a calculation unit that calculates a travel distance of the moving object in a specified period of time using the travel speed detected by the speed sensor; an update unit that updates the accumulated mileage stored in the storage unit by adding the mileage calculated by the calculation unit to the accumulated mileage stored in the storage unit for each of the specified periods; The traveling distance calculation device according to claim 1, further comprising:

3. The detection unit a travel distance detection sensor capable of directly detecting a travel distance of the moving body; an updating unit that updates the accumulated mileage stored in the storage unit at a specified cycle by using the mileage detected by the mileage detection sensor as the accumulated mileage; The traveling distance calculation device according to claim 1, further comprising:

4. the correction unit corrects the cumulative traveling distance using the second error rate according to the variation in the error included in the detection value detected by the sensor.

2. The traveling distance calculation device according to claim 1.

5. a variation in the error included in the detection value detected by the sensor is expressed by a normal distribution, and the first error rate is within a specified range including 0; 5. The traveling distance calculation device according to claim 4.

6. When correcting the accumulated travel distance of the moving body, the correction unit corrects the leading position of the moving body so as to extend it in the direction of travel of the moving body, and corrects the trailing position of the moving body so as to extend it in the direction opposite to the direction of travel of the moving body, in accordance with the variation in the error included in the detection value detected by the sensor and the first error rate.

2. The traveling distance calculation device according to claim 1.

7. When a second accumulated mileage acquired from the memory unit after a first accumulated mileage acquired from the memory unit is greater than the first accumulated mileage and the second corrected accumulated mileage after correcting the second accumulated mileage is smaller than the first corrected accumulated mileage after correcting the first accumulated mileage, the correction unit adopts the first corrected accumulated mileage or a value obtained by increasing the first corrected accumulated mileage by a specified rate as a corrected value of the second accumulated mileage.

2. The traveling distance calculation device according to claim 1.

8. When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the running distance calculation device mounted on each of the same type of moving body is set in common depending on the type of the moving body; 8. The travel distance calculation device according to claim 1, wherein the travel distance calculation device is a travel distance calculation device.

9. When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the mileage calculation device mounted on each of the same type of moving bodies is set individually for each of the moving bodies in accordance with the characteristics of the sensor when the sensor is installed on each of the moving bodies; 8. The travel distance calculation device according to claim 1, wherein the travel distance calculation device is a travel distance calculation device.

10. A mileage calculation method for a mileage calculation device, comprising: a detection step in which a detection unit detects a travel distance of the mobile object using a sensor having an average error rate of errors included in detected values ​​that is a first error rate; a correction step in which a correction unit corrects the accumulated travel distance by multiplying the accumulated travel distance stored in a storage unit that stores an accumulated travel distance based on the travel distance of the moving object detected by the detection unit by a second error rate that is varied so as to converge to the first error rate as the accumulated travel distance becomes longer; A traveled distance calculation method comprising:

11. The detecting step a speed detection step in which a speed sensor detects a traveling speed of the moving object; a calculation step in which a calculation unit calculates a travel distance of the mobile object in a specified period using the travel speed detected by the speed sensor; an updating step in which an updating unit updates the accumulated mileage stored in the storage unit by adding the mileage calculated by the calculation unit to the accumulated mileage stored in the storage unit for each of the specified periods; The method for calculating a traveled distance according to claim 10, further comprising:

12. The detecting step a travel distance detection step in which the travel distance detection sensor directly detects the travel distance of the moving object; an updating step in which an updating unit updates the accumulated mileage stored in the storage unit at a specified cycle by using the mileage detected by the mileage detection sensor as the accumulated mileage; The method for calculating a traveled distance according to claim 10, further comprising:

13. In the correcting step, the corrector corrects the cumulative traveling distance using the second error rate corresponding to a variation in the error included in the detection value detected by the sensor. The traveled distance calculation method according to claim 10.

14. a variation in the error included in the detection value detected by the sensor is expressed by a normal distribution, and the first error rate is within a specified range including 0; 14. The method for calculating a traveled distance according to claim 13.

15. In the correction step, when correcting the accumulated travel distance of the moving body, the correction unit corrects the leading position of the moving body so as to be extended in the direction of travel of the moving body, and corrects the trailing position of the moving body so as to be extended in the direction opposite to the direction of travel, in accordance with the variation in error included in the detection value detected by the sensor and the first error rate. The traveled distance calculation method according to claim 10.

16. In the correction step, when a second accumulated mileage acquired from the memory unit after a first accumulated mileage acquired from the memory unit is greater than the first accumulated mileage and the second corrected accumulated mileage after correcting the second accumulated mileage is smaller than the first corrected accumulated mileage after correcting the first accumulated mileage, the correction unit adopts the first corrected accumulated mileage or a value obtained by increasing the first corrected accumulated mileage by a specified rate as a corrected value of the second accumulated mileage. The traveled distance calculation method according to claim 10.

17. When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the running distance calculation device mounted on each of the same type of moving body is set in common depending on the type of the moving body; 17. The method for calculating a traveled distance according to claim 10, wherein the method comprises:

18. When there are a plurality of the same type of moving bodies equipped with the mileage calculation device, the second error rate used in the correction unit of the mileage calculation device mounted on each of the same type of moving bodies is set individually for each of the moving bodies in accordance with the characteristics of the sensor when the sensor is installed on each of the moving bodies; 17. The method for calculating a traveled distance according to claim 10, wherein the method comprises:

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