DEVICE FOR ESTIMATE ONE'S OWN POSITION

Abstract

A device for estimating its own position comprises the following: a position information acquisition unit in a vehicle, a first memory containing encrypted map information, a microcomputer that reads the map information, performs a calculation based on information received from the position information acquisition unit and outputs driver assistance information, and a second memory that holds the map information and current position information transmitted by the microcomputer. The position information acquisition unit, the first memory, and the second memory are connected to the microcomputer via a communication line, and the second memory is non-volatile memory of the vehicle that stores information about its own position, encrypted peripheral map information, and decrypted peripheral map information during vehicle operation.

Description

Technical field

[0001] The present invention relates to a self-position estimating device and a driving assistance device, and relates, for example, to a self-position estimating device that loads map data for driving assistance into a non-volatile memory and a driving assistance device having a self-position estimating function. Technical background

[0002] In recent years, a large number of non-volatile memories have been developed that can be overwritten many times, some of which have been commercially deployed. Typical examples include magnetoresistive memory (MRAM), ferroelectric memory (FeRAM), resistance-change memory (ReRAM), phase-change memory (PRAM), and carbon nanotube memory (NRAM). Because the memory can be overwritten many times and is non-volatile, it is expected to be used in a variety of applications.

[0003] PTL 1 discloses a device using such a non-volatile memory. This publication discloses a control method for obtaining access performance when using FeRAM or the like as RAM. In addition, PTL 2 discloses a case where FeRAM is used as a memory area in which a program is written. Citation listPatent literature PTL 1: JP 2020-21450 A PTL 2: JP 2019-185398 A Summary of the inventionTechnical problem

[0004] In recent years, there has been an increasing demand for a self-position estimation function in a motor vehicle's driving assistance system. This is due to the demand for driving assistance based on self-position and corresponding map data, including the mandatory support of ISA (intelligent speed assistance) in Europe.

[0005] However, the conventional self-position estimation device has various problems, two of which are particularly significant. One is the length of time from activation to the time when self-position information can be used for driving assistance. This is because it takes time to calculate position information using a GNSS, and it is necessary to acquire and develop peripheral map data after the estimation of self-position information is completed. Accordingly, it is not possible to perform driving assistance based on self-position information during a predetermined period after the ignition is turned on.

[0006] The other is that large-capacity memory is required to handle large amounts of map data. In particular, in a low-cost microcomputer that lacks DRAM I / F, it is impossible to process the map data due to low RAM capacity, thus requiring a costly SoC. In particular, the self-position estimation device becomes costly due to the latter reasons, and this is one of the factors hindering the widespread adoption of driving assistance with more features. Solution to the problem

[0007] An example of a device for estimating its own position according to the present invention includes the following: a position information acquisition unit in a vehicle, a first memory in which encrypted map information is stored, a microcomputer that reads the map information, performs a calculation based on information obtained from the position information acquisition unit, and outputs driving support information, and a second memory that holds the map information and current position information transmitted from the microcomputer.The position information acquisition unit, the first memory, and the second memory are connected to the microcomputer via a communication line, and the second memory is a non-volatile memory of the vehicle that stores self-position information, encrypted peripheral map information, and decrypted peripheral map information during operation of the vehicle.

[0008] An example of a driving assistance device according to the present invention includes: the self-position estimating device described above, which has a self-position estimating function and a function of executing driving assistance using a self-position estimated by the self-position estimating function. Advantageous effects of the invention

[0009] By using the self-position estimating device according to the example of the present invention, map data can be handled in a system using an inexpensive microcomputer that does not have a DRAM I / F, so that the cost of the self-position estimating device can be reduced.

[0010] In addition, by using the self-position estimating device according to the example of the present invention in a system using an inexpensive microcomputer that does not have a DRAM I / F, peripheral map information can be acquired from the outside via the Internet or the like, and calculation can be performed. This can reduce the cost of the self-position estimating device.

[0011] In addition, by using the self-position estimating device according to the example of the present invention, the risk of extracting map information from the self-position estimating device after a trip can be avoided.

[0012] In addition, by using the self-position estimating device according to the example of the present invention, the driving assistance can be initiated soon after activation by estimating the self-position, and the driving assistance can be realized at the start of driving.

[0013] In addition, as in the driving support device according to the example of the present invention, it is also possible to integrate a device on a side where a self-position estimation function is provided and a device on a side where driving support is performed using information provided by the self-position estimation device. Brief description of the drawings

[0014] They show: Fig. 1 shows a configuration of a device for estimating one's own position according to Example 1, Fig. 2 shows a memory configuration and a data shift of the device for estimating one's own position according to Example 1, Fig. 3 is a flowchart showing the procedure of an operation of the self-position estimating device according to Example 1, Fig. 4 shows a configuration of a device for estimating one’s own position according to Example 2, Fig. 5 is a flowchart showing the flow of an operation of a self-position estimating device according to Example 3, and Fig. 6 is a flowchart showing the procedure of an operation of a self-position estimating device according to Example 4. Description of embodiments

[0015] Hereinafter, Examples 1 to 4 of a self-position estimating device and Example 5 of a driving support device will be described with reference to the drawings. [Example 1]

[0016] Fig. 1 shows a configuration of a self-position estimation device according to Example 1 of the present invention. A self-position estimation device 101 includes a microcomputer 102, a position information acquisition unit 103 in a vehicle, a non-volatile memory 104 (second memory), and a high-capacity memory 105 (first memory). The microcomputer 102 includes a processor. The position information acquisition unit 103 has a sensor group related to position information acquisition, and includes, for example, a global navigation satellite system (GNSS) information acquisition unit 106 and an inertial measurement unit (IMU) sensor 107. The GNSS information acquisition unit 106 can acquire information provided by satellite navigation.

[0017] The position information acquisition unit 103 (specifically, the GNSS information acquisition unit 106 and the IMU sensor 107), the non-volatile memory 104, and the high-capacity memory 105 are each connected to the microcomputer 102 via a communication line.

[0018] The high-capacity memory 105 stores encrypted card information. For example, the high-capacity memory 105 stores encrypted card information 110 of a large area. The non-volatile memory 104 stores peripheral card information. The peripheral card information includes encrypted peripheral card information 109 obtained by copying a necessary part of the encrypted card information 110 and decrypted peripheral card information 108 generated by decrypting the encrypted peripheral card information.

[0019] The non-volatile memory 104 may be an MRAM, a FeRAM, a ReRAM, a PRAM, or an NRAM. The use of these memories is preferred because the number of rewrites is very large. The high-capacity memory 105 is a low-cost, high-capacity non-volatile memory such as a NAND flash memory, but it is not limited to the written memory as long as the memory has this characteristic.

[0020] In addition, the GNSS information acquisition unit 106 and the IMU sensor 107 were described as examples of the position information acquisition unit 103, but this is a representative example of a sensor that can be used for position information acquisition, and the sensor type is not limited to this. For example, the sensor may use a camera.

[0021] Furthermore, the term "encryption" for the encrypted card information 110 and the decrypted peripheral card information 109 does not limit the encryption scheme. Additionally, obfuscation may be included instead of so-called encryption. For example, if it is not subject to a specific definition of the term "encryption," it suffices that the card information is difficult to read compared to the card information before processing. As a specific example, information that can be read by a predetermined calculation without knowing a decryption key is included.

[0022] Fig. 2 shows a memory configuration and data movement of the self-position estimating device 101 according to the present example. Fig. 2 will be described in particular focusing on the data shifting of the device 101 for estimating its own position.

[0023] The self-position estimation device 101 according to the present embodiment first copies, based on the self-position estimation information (for example, information indicating the estimated self-position of the vehicle), encrypted map information of a predetermined area around the self-position from the encrypted map information 110 stored in the high-capacity memory 105 to the nonvolatile memory 104 as encrypted peripheral map information 109. Since the data is transferred sequentially, no problem arises even if the size of the RAM of the microcomputer 102 itself is smaller than the data size of the encrypted peripheral map information 109.

[0024] Then, data contained in the encrypted peripheral card information 109 is sequentially read by the microcomputer 102 and written into the nonvolatile memory 104 as decrypted peripheral card information 108. Even if the size of the RAM of the microcomputer 102 itself is smaller than the data size of the encrypted peripheral card information 109 or the decrypted peripheral card information 108, no problems arise because the data is transferred and processed sequentially.

[0025] The non-volatile memory 104 stores self-position estimation information 205 (self-position information) representing the estimated self-position of the vehicle, and the microcomputer 102 can read and write the self-position estimation information 205. The self-position estimation information 205 can be obtained, for example, from the position information acquisition unit 103.

[0026] As described above, the non-volatile memory 104 holds the map information (for example, the encrypted peripheral map information 109 and the decrypted peripheral map information 108) and the current position information (for example, the self-position estimation information 205) transmitted from the microcomputer 102.

[0027] Fig. 3 is a flowchart showing an operation flow of the self-position estimation device 101 according to the present example, specifically showing movement during operation (during normal operation). While traveling, the self-position estimation device 101 updates the self-position estimation information 205 based on information periodically acquired by the position information acquisition unit 103 (S100). Then, based on the self-position estimation information 205, it is determined whether it is necessary to read the nearest peripheral map information (S110). For example, based on the read self-position, it is determined whether or not all the map information pieces in a predetermined area have been read.If a portion has not been read, it is determined that the next peripheral card information needs to be read. If the next peripheral card information needs to be read, the unused peripheral card information is deleted from the non-volatile memory (S120). At this time, corresponding portions of both the encrypted peripheral card information 109 and the decrypted peripheral card information 108 are deleted.

[0028] After the non-volatile memory 104 becomes available through erasure, the encrypted peripheral card information 109 is read based on the area where the peripheral card is needed and copied to the non-volatile memory 104 (S130). After that, the encrypted peripheral card information 109 newly loaded into the non-volatile memory 104 is decrypted by the microcomputer 102 while being read, and the decrypted peripheral card information 108 is written to the non-volatile memory (S140).

[0029] As described above, the non-volatile memory 104 stores the self-position information (for example, the self-position estimation information 205), the encrypted peripheral map information (for example, the encrypted peripheral map information 109), and the decrypted peripheral map information (for example, the decrypted peripheral map information 108) during operation of the vehicle.

[0030] After the decryption of the decrypted peripheral map information 108 is completed, information necessary for driving assistance is provided to the driving assistance device based on the self-position estimation information 205 and the information included in the decrypted peripheral map information 108 (S150). As described above, the microcomputer 102 reads the map information, performs calculation based on the information obtained from the position information acquisition unit 103, and outputs driving assistance information. The driving assistance information includes, for example, information regarding a speed limit, information regarding a sharp turn, information regarding a gradient of a road, and the like.

[0031] If it is determined in S110 that reading the next peripheral map is unnecessary, the information necessary for driving assistance is provided to the driving assistance device based on the self-position estimation information 205 and that of the decrypted peripheral map information 108 currently in the non-volatile memory 104 (S150).

[0032] As described above, by the self-position estimating device 101 according to the present example, even if the low-cost microcomputer 102 having no DRAM I / F but a RAM having a relatively small size is used, practical map data can be handled, so that the cost of the self-position estimating device 101 can be reduced. [Example 2]

[0033] Fig. 4 shows a configuration of a self-position estimating device according to Example 2 of the present invention. Hereinafter, the description of parts similar to those of Example 1 may be omitted.

[0034] A self-position estimating device 401 includes a microcomputer 102, a position information acquisition unit 103 in a vehicle, a non-volatile memory 104 (memory), and a communication IC 405 (a network interface).

[0035] The position information acquisition unit 103 (specifically, a GNSS information acquisition unit 106 and an IMU sensor 107), the communication IC 405, and the non-volatile memory 104 are connected to the microcomputer 102 via a communication line.

[0036] The communication IC 405 is connected via a network to a map server 411 in a data center 410. In response to a request from the communication IC 405 relating to a specific area, the map server 411 acquires map information about that area from the encrypted map information 412 of a large area and transmits the acquired map information to the communication IC. The communication IC 405 receives the map information and transmits it to the microcomputer 102.

[0037] Peripheral card information is stored in non-volatile memory 104. The peripheral card information includes the received encrypted peripheral card information 109 and the decrypted peripheral card information 108 generated by decrypting the encrypted peripheral card information.

[0038] As described above, the non-volatile memory 104 holds the encrypted map information (for example, the encrypted peripheral map information 109) acquired and transmitted from the microcomputer 102 via the network and the current position information (for example, the self-position estimation information).

[0039] The non-volatile memory 104 is not limited to the described memory as long as it has the same characteristics as the non-volatile memory 104 according to Example 1. In addition, the communication IC 405 is an IC that can be connected to an external network such as an Ethernet (registered trademark) and is compatible with a communication scheme that can handle high-capacity data such as map data, but the communication scheme is not limited thereto.

[0040] In addition, the type of the sensor of the position information acquisition unit 103 is similarly not limited to the position information acquisition unit 103 according to Example 1.

[0041] Furthermore, the encryption scheme of the encrypted card information 412 and the encrypted peripheral card information 109 is not limited and may be obfuscated instead of so-called encryption.

[0042] The operation of the self-position estimating device 401 according to Example 2 is the same as the operation of the self-position estimating device 101 according to Example 1, with the difference being whether the storage location of the encrypted map is inside or outside the self-position estimating device. Therefore, the map server 401 corresponds to the high-capacity memory 105 in Fig. 1, while the other data flows are similar, and the operation in Fig. 3 corresponds to that of the device (1) for estimating its own position according to Example 1.

[0043] In particular, the microcomputer 102 performs a calculation based on the information obtained by the position information acquisition unit 103 and outputs driving support information. In addition, the non-volatile memory 104 stores the information about its own position (for example, the information 205 for estimating its own position), the encrypted peripheral card information (for example, the encrypted peripheral card information 109), and the decrypted peripheral card information (for example, the decrypted peripheral card information 108) during the operation of the vehicle.

[0044] As described above, by the self-position estimation device 401 according to the present example, even when an inexpensive microcomputer 102 that does not have a DRAM I / F is used, peripheral map information can be obtained from the outside via the Internet or the like and calculation can be performed. This can reduce the cost of the self-position estimation device. [Example 3]

[0045] A self-position estimating device according to Example 3 is obtained by adding a process after the self-position estimating device according to Example 1 or 2 for safety reasons. Hereinafter, the description of parts similar to those of Example 1 or 2 may be omitted.

[0046] Fig. 5 is a flowchart showing the procedure of an operation of the self-position estimating device according to Example 3. Fig. 5 shows the processing related to the end of an operation of the self-position estimating device.

[0047] When a stop request (which may be referred to as a termination notification) arrives at the self-position estimating device due to the ignition of a motor vehicle or the like being turned off (S200), the self-position estimating device deletes the decrypted peripheral map information 108 stored in the non-volatile memory 104 (S210). It is then determined whether the deletion of the decrypted peripheral map information 108 has been completed (S220). If the deletion has not been completed (S220: NO), the processing of deleting the decrypted peripheral map information 108 that has not yet been deleted is executed or continued (S210, as described above). As described above, the microcomputer 102 discards the decrypted peripheral map information in response to the stop request.When the deletion of the decrypted peripheral card information 108 is confirmed (S220: YES), the operation is interrupted (S230).

[0048] This can prevent the decrypted peripheral map information 108 from being read from the outside after the operation is interrupted. That is, the risk of the map information being extracted from the self-position estimation device after the trip can be avoided.

[0049] Even if the self-position estimation information 205 and the encrypted peripheral map information 109 are stored in the non-volatile memory 104, the microcomputer 102 does not delete the self-position estimation information 205 and the encrypted peripheral map information 109. That is, the microcomputer 102 stores the self-position estimation information 205 and the encrypted peripheral map information 109 when the operation is interrupted. [Example 4]

[0050] A self-position estimating device according to Example 4 is capable of setting the start time of driving assistance early with respect to the self-position estimating device according to Example 3 by using the encrypted peripheral map information and the self-position estimating information stored in the non-volatile memory upon activation. Hereinafter, the description of parts similar to those of Example 3 may be omitted.

[0051] Fig. 6 shows the flow of an operation of the self-position estimating device according to Example 4. Fig. 6 shows an operation related to the activation of the device for estimating one's own position.

[0052] When the self-position estimation device is activated by turning on the vehicle's ignition or the like (S300), it determines whether the self-position estimation information 205 and the encrypted peripheral map information 109 are stored in the non-volatile memory 104 (S310). As described above, in response to the vehicle activation, the microcomputer 102 refers to the self-position estimation information 205 and the encrypted peripheral map information 109 stored in the non-volatile memory 104.

[0053] If the self-position estimation information 205 and the encrypted peripheral map information 109 are stored (S310: YES), the encrypted peripheral map information 109 is decrypted (S320). As described above, if the self-position estimation information 205 and the encrypted peripheral map information 109 are present in the non-volatile memory 104, the microcomputer 102 decrypts the encrypted peripheral map information 109 and stores the decrypted peripheral map information in the non-volatile memory 104.

[0054] When the output of the decrypted peripheral map information 108 to the non-volatile memory is completed, the self-position estimation information 205 and the decrypted peripheral map information 108 are read, and the calculation of information necessary for driving assistance is initiated based on these pieces of information (S321), and driving assistance is initiated (S322). As described above, the microcomputer 102 outputs the driving assistance information by using the self-position estimation information 205 and the decrypted peripheral map information 108.

[0055] Because processing up to this point only requires GNSS, driving assistance can be initiated earlier than in a configuration where self-position is estimated using GNSS or similar information, and reading of the encrypted peripheral map information begins after self-position estimation is completed. This means that driving assistance can be initiated soon after starting by estimating self-position, and driving assistance can be provided from the start of driving.

[0056] In S320 to S322, any available sensor (IMU sensor 107 or other sensor) can be used. Furthermore, when GNSS becomes available, the own position estimation can be performed with higher accuracy if the use of GNSS information is initiated at that time.

[0057] If the encrypted peripheral map information 109 is not stored in the nonvolatile memory 104 at the startup time or the like (S310: NO), the position information is acquired as in the conventional self-position estimation device (S330). It is repeatedly determined whether the acquisition of the position information is completed (S340). When the acquisition of the position information is completed, necessary encrypted peripheral map information is sequentially copied from the encrypted peripheral map information 109 to the nonvolatile memory 104 (S350). The encrypted peripheral map information 109 is decrypted (S351). The self-position estimation information 205 and the decrypted peripheral map information 108 are read (S352).The calculation of information necessary for driving assistance is initiated based on these information components, and driving assistance is initiated (S353).

[0058] In this case, the time from startup to the start of driving assistance cannot be shortened. However, the self-position estimation information 205 and the encrypted peripheral map information 109 remain in the non-volatile memory at the end of normal operation (see Example 3), so cases where this is not possible can be limited to a small proportion. [Example 5]

[0059] The driving assistance device according to the present example is configured such that a device, which is one of the self-position estimation devices according to Examples 1 to 4, performs its own position estimation and outputs driving assistance information while simultaneously performing driving assistance using the information. That is, the self-position estimation device 101 also functions as a driving assistance device. Hereinafter, the description of parts similar to those of any of Examples 1 to 4 may be omitted.

[0060] For example, the microcomputer 102 has a multi-core configuration, that is, it has a number of processors. Then, one or more of the processors implements the self-position estimation device according to any one of Examples 1 to 4, and another one or more of the processors implements the driving assistance device.

[0061] As described above, the driving assistance device according to the present example includes the self-position estimation device and has the self-position estimation function. Then, the driving assistance device has the function of executing driving assistance using the self-position estimated by the self-position estimation function.

[0062] Although the specific contents of driving support are not particularly limited, those skilled in the art can appropriately design and support operations related to, for example, an accelerator pedal, a brake, a steering, and the like based on a known technique or the like.

[0063] An effect of the self-position estimation device according to Examples 1 to 4 is that the role of the self-position estimation device can be realized by an inexpensive microcomputer. Accordingly, the self-position estimation device can be integrated with a driving assistance device realized by an inexpensive microcomputer, and it can be achieved that highly functional driving assistance based on the self-position estimation can be realized even by an inexpensive driving assistance device. That is, it is possible to integrate a device on the side where the self-position estimation function is provided and a device on the side where driving assistance is performed using information provided by the self-position estimation device. List of reference symbols 101 Device for estimating one's own position (driving assistance device) 102 microcomputers 103 Position information acquisition unit 104 non-volatile memory (second memory) 105 high-capacity memory (first memory) 106 GNSS information acquisition unit 107 IMU sensor 108 decrypted peripheral card information (decrypted peripheral card information) 109 encrypted peripheral card information (encrypted peripheral card information) 110 encrypted card information 205 Information for estimating one's own position (information about one's own position) 401 Device for estimating one's own position (driving assistance device) 405 Communication IC (network interface) QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2020-21450 A

[0003] JP 2019-185398 A

[0003]

Claims

[1] Device for estimating one’s own position, comprising: a position information acquisition unit in a vehicle, a first memory in which encrypted card information is stored, a microcomputer that reads the map information, performs a calculation based on information obtained from the position information acquisition unit, and outputs driving support information, and a second memory that holds the map information and current position information transmitted by the microcomputer, wherein the position information acquisition unit, the first memory and the second memory are connected to the microcomputer via a communication line, and the second memory is a non-volatile memory of the vehicle and stores information about its own position, encrypted peripheral map information and decrypted peripheral map information during operation of the vehicle. [2] Device for estimating one’s own position, comprising: a position information acquisition unit in a vehicle, a microcomputer that performs a calculation based on information obtained from the position information acquisition unit and outputs driving support information, and a memory that holds encrypted map information and current position information acquired and transmitted by the microcomputer via a network interface, wherein the position information acquisition unit, the network interface and the memory are connected to the microcomputer via a communication line and the memory is a non-volatile memory of the vehicle and stores information about its own position, encrypted peripheral map information and decrypted peripheral map information during operation of the vehicle. [3] Device for estimating one’s own position according to claim 1 or 2, wherein the microcomputer discards the decrypted peripheral card information in response to a service interrupt request and the microcomputer stores its own position information and encrypted peripheral card information when the microcomputer interrupts operation. [4] Device for estimating one’s own position according to claim 1, wherein the microcomputer, in response to activation of the vehicle, refers to the information about its own position and the encrypted peripheral map information stored in the second memory, the microcomputer decrypts the encrypted peripheral card information and stores a decryption result in the second memory if the self-position information and the encrypted peripheral card information are contained in the second memory, and the microcomputer outputs the driving support information using the self-position information and the decrypted peripheral map information. [5] The self-position estimating device according to claim 1, wherein the second memory is an MRAM, a FeRAM, a ReRAM, a PRAM or an NRAM. [6] Driving assistance device, comprising: the device for estimating one's own position according to claim 1 or 2, wherein a function for estimating one's own position and a function for performing driving assistance using one's own position estimated by the function for estimating one's own position are provided.

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