Flight accident recorder data repair method and system in case of synchronization word loss

Abstract

The present invention discloses a method and system for repairing data of a flight accident recorder in the case of synchronization word loss, and the method includes: S1, the flight accident recorder performs distributed activation of storage fragments according to storage chips to store data in sequence; S2, the data stored in the flight accident recorder is read in sequence, and the broken or damaged parts are spliced ​​and filled with blank data; S3, the subframe synchronization word of the data frame is searched and located by the bit shift operation method for the binary data stream, and the complete data frame data is segmented and stored; a synchronization word correction logic rule base is constructed and the synchronization word is repaired or corrected or repaired. The present invention reads and processes the binary data by reading the data buffer area, and then performs synchronization word repair and data verification processing on the binary data stream, which solves the technical problem that the data cannot be decoded and obtained due to the lack of synchronization words, and provides technical support for subsequent comprehensive, accurate and fast decoding.

Description

Technical Field

[0001] The invention relates to the field of aviation safety investigation, and in particular to a method and system for repairing data of a flight accident recorder in the case of synchronization word loss. Background Art

[0002] A flight accident is an incident that directly threatens safe operation or causes casualties, damage to the aircraft, or disappearance during the entire flight process from engine start-up before takeoff to engine shutdown after landing. The main causes of flight accidents include bad weather, pilot operation, aircraft mechanical or system failure, air traffic control errors, bird strikes, etc. Since the various losses and adverse effects caused by flight accidents are extremely serious, it is particularly important to find the real cause of flight accidents and prevent similar accidents from happening again.

[0003] In order to accurately and in real time record the actual flight process and status of each flight, according to the mandatory requirements of civil aviation regulations of various countries in the world, passenger, cargo and helicopter aircraft must be equipped with flight data recorders. Airborne flight data recorders are mainly used to record various data such as the flight status of the aircraft, crew operations, operation of various aircraft systems and equipment, external environment, etc., so as to realize the investigation of the cause of flight accidents, data analysis of unsafe events and cases, and provide detailed data support for the improvement of aircraft design and maintenance or training plans. The flight data recorded by the flight data recorder (or flight accident recorder) is crucial for the investigation and analysis of the cause of civil aviation flight accidents. When the flight data recorder is damaged or destroyed due to a flight accident, the repair technology of the data recorded by the damaged recorder is of great significance to the technical guarantee and improvement of civil aviation safety.

[0004] When reading the flight accident recorder with the help of tools, the synchronization word is often identified and the binary data stream is read. Due to aircraft accidents, storage chip damage, storage errors and other reasons, it may lead to situations such as unrecognizable, unreadable or partial data loss. Subsequent data deciphering and decoding becomes very difficult. For example, the loss of the data frame synchronization word will cause the recorder data to be unable to be decoded, and then the recorded data cannot be obtained. How to fill and repair the data when the synchronization word is lost (such as loss or incompleteness) to provide technical support for subsequent comprehensive, accurate and fast decoding is a major difficulty in the data processing of flight accident recorders, and it is also an important research direction for civil aviation accident investigation and safety assurance technology. Summary of the invention

[0005] The purpose of the present invention is to overcome the technical problems pointed out by the background technology, and to provide a data repair method and system for a flight accident recorder in the event of a synchronization word loss. The method and system read and process binary data by reading a data buffer area, and then perform synchronization word repair and data verification processing on the binary data stream, thereby solving the technical problem that data cannot be decoded and obtained due to the loss of synchronization words, and providing technical support for subsequent comprehensive, accurate and fast decoding.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A method for repairing data of a flight accident recorder when a synchronization word is lost, the method comprising:

[0008] S1. The data storage component of the recorder of the flight accident recorder is composed of N memory chips, each memory chip contains M memory segments, and the flight accident recorder uses the memory chips to enable the memory segments in a distributed manner to store data in sequence. The flight accident recorder stores data according to a fixed data frame structure. Each data frame includes four subframes, each subframe contains a number of words, each word includes 12 bits, and the first word of the data frame subframe is the synchronization word of the subframe;

[0009] S2. Read the data stored in the flight accident recorder in sequence. If the storage segment DATAij is damaged or broken, and the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, blank data is used to fill the gap and record it;

[0010] S3. Use the bit shift operation method to search and locate the subframe synchronization word of the data frame for the binary data stream read from the flight accident recorder, and divide and store the complete data frame data; perform synchronization word repair and data verification processing on the remaining binary data stream:

[0011] If the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer to operate bit by bit to sequentially obtain 12 bits of data and determine whether it is the synchronization word of the subframe, then the pointer is moved back one bit to obtain 12 bits of data and determine whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found; then a synchronization word correction logic rule base is constructed based on the data frame structure, the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed;

[0012] Finally, all stored data are decoded.

[0013] In order to better implement the data repair method of the present invention in the case of synchronization word loss, in step S3, the synchronization word correction logic rule base records the logic rules for correcting the synchronization word loss based on the synchronization words identified before and after.

[0014] A further technical solution, step S3 also includes the following method: the synchronization word correction logic rule base stores mutual verification correction rules for locating the word position of the synchronization word with reference to the feature data, searches the reference feature data and logically verifies the word position of the synchronization word and repairs the synchronization word, and records it in a log file, and the reference feature data is a continuity and correlation feature.

[0015] A further technical solution is a method for searching reference feature data as follows: starting from bit 0 in the binary data stream, a reference feature data search is performed and the data is verified through continuity and correlation, and then the word bit of the synchronization word is located based on the word bit verification and correction rule and the synchronization word is repaired; if the reference feature data cannot be found, the binary data stream is shifted right by one bit to perform a reference feature data search and the data is verified through continuity and correlation, and then the word bit of the synchronization word is located based on the word bit verification and correction rule and the synchronization word is repaired; the binary data stream continues to shift right until the synchronization word is repaired.

[0016] Preferably, all data of all patched, corrected or / and repaired synchronization words are stored, and data output is performed using a byte-by-byte data processing method.

[0017] Preferably, in step S3, a read data buffer is set to perform synchronization word correction processing.

[0018] Preferably, in step S3, data gaps between adjacent data frames are removed and recorded in a log file.

[0019] A data repair system for a flight accident recorder in the case of synchronization word loss comprises a flight accident recorder, a data reading module, a synchronization word search module, a storage module and a decoding device. The recorder data storage component of the flight accident recorder is composed of N storage chips, each storage chip contains M storage segments, the flight accident recorder performs distributed activation of the storage segments according to the storage chips to sequentially store data, the flight accident recorder stores data according to a fixed-architecture data frame structure, each data frame includes four subframes, each subframe contains a number of word words, each word word includes 12 bits, and the first word word of the subframe of the data frame is the synchronization word of the subframe; the data reading module reads the data stored in the flight accident recorder in sequence, if the storage segment DATAij read is damaged or broken, the storage segment DATAij is the i-th storage chip, the j-th storage segment, 1≤i≤N, 1≤j≤M, then blank data is used for splicing and filling and recording; the synchronization word search module uses a bit shift operation method to search and locate the synchronization word of the subframe of the data frame for the binary data stream read by the flight accident recorder, and The complete data frame data is segmented and stored; the synchronization word search module has a synchronization word correction module inside, the synchronization word correction module has a synchronization word correction logic rule base, and the synchronization word correction module performs synchronization word repair and data verification processing on the remaining binary data stream, the method is as follows: if the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer bit operation to take 12 bits of data in sequence and judge whether it is the synchronization word of the subframe, then the pointer is moved back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found; then based on the data The frame structure constructs a synchronization word correction logic rule base, and based on the synchronization word correction logic rule base, the missing synchronization word in the data frame is repaired or corrected, and a log file of the synchronization word repair and correction record is constructed; the synchronization word correction logic rule base stores the word word position mutual verification correction rules of the synchronization word located by reference to the feature data, searches the reference feature data and logically verifies the word word position of the synchronization word and repairs the synchronization word, and records it in the log file, and the reference feature data is a continuity and correlation feature; the storage module is used for data storage, and the decoding device performs decoding processing.

[0020] An electronic device comprises: at least one processor; and a memory connected to the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the data repair method of the flight accident recorder of the present invention in the event of synchronization word loss.

[0021] A storage medium stores a computer program, which, when executed by a processor, implements the steps of a data repair method for a flight accident recorder in the event of synchronization word loss of the present invention.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] (1) The present invention provides a method for repairing data in the event of synchronization word loss. The method reads and processes binary data (including splicing and completion) by reading a data buffer area, and then performs synchronization word repair and data verification processing on the binary data stream. The synchronization word of each data frame can be corrected and repaired, solving the technical problem that data cannot be decoded and acquired due to missing synchronization words, providing technical support for subsequent comprehensive, accurate and fast decoding, and providing a technical solution for accident investigation and analysis.

[0024] (2) The present invention has developed a series of data repair enhancement technologies, including data mutual verification technology, data cache area size reasonable selection and other efficient data processing methods, and storage technology of recovery process parameter record files to facilitate subsequent data inspection operations, which can well meet the needs of future accident investigation and event analysis.

[0025] (3) In addition to being able to solve the problem of incomplete synchronization words, the present invention can also solve the technical problem of complete loss of synchronization words. It proposes a method for mutual verification of features of related data, a bit / byte bit stream algorithm control technology, a data frame data gap processing technology, etc., which provides a complete solution for comprehensive acquisition and repair of flight data, facilitates subsequent comprehensive reading and storage of binary data, and fast, comprehensive and accurate decoding. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A method flow chart of a data repair method in the case of synchronization word loss according to the present invention;

[0027] Figure 2 A schematic diagram of a distributed enabled storage segment storing data in an embodiment;

[0028] Figure 3 A schematic diagram of data reading and blank data splicing and filling in the embodiment;

[0029] Figure 4 The principle structure block diagram of the data repair system of the present invention when the synchronization word is lost;

[0030] Figure 5 A schematic diagram of the processing principle of synchronization word repair and data verification processing in Embodiment 2;

[0031] Figure 6 Schematic diagram of the search and processing principle of adjacent data frame gaps in the embodiment;

[0032] Figure 7 It is a statistical table diagram of data frame synchronization word search and error synchronization word in embodiment 2;

[0033] Figure 8 The data output algorithm in the embodiment takes a data frame of 512 words as an example;

[0034] Fig. 9 Schematic diagram of a data repair processing log file in an embodiment. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with embodiments:

[0036] Embodiment 1

[0037] like Figure 1 As shown, a method for repairing data of a flight accident recorder when a synchronization word is lost is characterized in that the method comprises:

[0038] S1. The recorder data storage component of the flight accident recorder is composed of N storage chips, each of which contains M storage segments. The flight accident recorder performs distributed activation of the storage segments according to the storage chips and performs data storage in sequence. Figure 2, the distributed activation method of storage segments is as follows: when storing data, first activate the first storage segment of N storage chips for distributed storage in sequence, then activate the second storage segment of N storage chips for distributed storage in sequence, and so on, the order of storage activation storage segments is: DATA11→DATA21→DATA31→……→DATA(N-1)1→DATAN1→DATA12→DATA22→DATA32→……→DATA(N-1)2→DATAN2→DATA13→DATA23→DATA33→…DATAij…→DATA(N-1)3→DATAN3→……; the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M. The flight accident recorder stores data according to a fixed-structure data frame structure, each data frame includes four subframes, each subframe contains a number of words, each word includes 12 bits, and the first word of the data frame subframe is the synchronization word of the subframe. The flight data recorder (or flight accident recorder) directly adopts the binary data stream data recording method of the data frame structure. The flight data recorder uses the data frame as its minimum storage unit, that is, the data to be transmitted is divided into data frames of fixed length. Each data frame contains information such as synchronization words, data and check codes. Each data frame is composed of 4 subframes. Each subframe data is of an agreed fixed length, and a specific pseudo-random Barker code synchronization word is used as the first data word of each subframe to identify the starting position of each subframe. Under normal circumstances, the acquisition and decoding of the flight data recorder first determine the starting position of each subframe by finding the synchronization words of each subframe of the data frame, and then complete the correct positioning and reading of each recorded parameter data based on this; if the data frame synchronization word of the flight data recorder is lost or incomplete, the original recorded data of the recorder cannot be read correctly, and it cannot be decoded, which leads to the inability to obtain the recorded data.

[0039] S2. Read the data stored in the flight accident recorder in sequence. If the storage segment DATAij is damaged or broken, and the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, then use blank data to fill in and record. Due to the impact and damage of the accident, a certain segment of data in a storage chip in the recorder data storage component of the data recorder is damaged and lost (if the storage chip is partially damaged, the chip may be unrecognizable and unreadable). In this way, the loss of some data (especially the loss of synchronization words) will cause the data to be unable to be read normally by the tool; because the synchronization words of the recorded data are lost due to the destruction of the recorder data chip fragment, the original damaged data of the recorder cannot be directly deciphered and decoded to obtain the actual flight data record value. For this reason, the original recorded data of the damaged recorder needs to be reconstructed and repaired to ensure that it meets the data decoding format requirements. When reading, the damaged or broken data in the storage segment is spliced, filled in or repaired. For example: Figure 3 As shown, if DATAN1 and DATA31 are broken or damaged, blank data should be used to fill in the gaps and record them.

[0040] S3. Use the bit shift operation method to search and locate the subframe synchronization word of the data frame for the binary data stream read from the flight accident recorder, and divide and store the complete data frame data. Perform synchronization word repair and data verification processing on the remaining binary data stream.

[0041] If the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer bit by bit operation to sequentially obtain 12 bits of data and determine whether it is the synchronization word of the subframe. Then the pointer moves back one bit to obtain 12 bits of data and determine whether it is the synchronization word of the subframe until the synchronization word of the subframe is found. Then, a synchronization word correction logic rule base is constructed based on the data frame structure, and the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed. Log file: a file that records characteristic data during the data recovery process; see Fig. 9 The file records the position of each frame of flight data in the original flight data (byte and bit offset relative to the file header), the data value of the synchronization word position, the decoded flight date, UTC time, frame counter, super frame counter and other data; by analyzing the log file, we can trace back to know which flight data frames have been repaired and the intervals between data frames.

[0042] Preferably, the synchronization word correction logic rule base records the logic rules for correcting the synchronization word loss based on the front and back identification of the synchronization word. The synchronization word correction logic rule base stores the front and back structures of the data frame and subframe synchronization word, and uses the pointer to sequentially take 12 bits of data from the 0th bit of the binary data stream according to the bit operation and judge whether it is the synchronization word of the subframe, and then the pointer moves back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found, so that the synchronization word is first found, and then the synchronization word is located, and the front and back structure rules of the data frame and subframe synchronization word in the synchronization word correction logic rule base are called, and other word words with incomplete synchronization words and errors (incomplete synchronization words and partial errors in synchronization words are a difficulty in reading data in the flight accident recorder, and the existing technology cannot read them out and data loss will occur) are located based on the structure of the data frame, and the synchronization word information of the word words is aligned based on the synchronization word correction logic rule base for repair or correction. The present invention uses a pointer to sequentially obtain 12 bits of data from the binary data stream starting from bit 0 and determine whether it is the synchronization word of the subframe, then the pointer moves back one bit to obtain 12 bits of data and determine whether it is the synchronization word of the subframe, so that the synchronization word and word position with complete synchronization words can be found, and then based on the determined synchronization word and word position, the word position of the pointer is moved to locate the word position with incomplete or wrong synchronization words, and then the synchronization word is repaired or corrected, so that the data can be identified and read out quickly. Then, the pointer can be used to verify the subframe synchronization word of the data frame, and the subframe length of the data frame moves the pointer back by a subframe length, and the subframe synchronization words of the data frame are found in turn, and the remaining incomplete synchronization words and verification synchronization words can be repaired based on the found data frame synchronization words. In some embodiments, a read data buffer area is set, and the synchronization word is repaired or corrected in the read data buffer area, so that the synchronization word correction process can be realized more quickly.

[0043] Finally, all stored data are decoded; all data of all patched, corrected or / and repaired synchronization words are stored (the storage of data only processes the missing data frame synchronization words, and other contents strictly keep the data consistent; if there are no missing synchronization words in the original flight data file, the repaired file is the same as the original flight data file; the present invention can decode more flight data on the time axis), and the byte-by-byte data processing method is used for data output.

[0044] Embodiment 2

[0045] A method for restoring data of a flight accident recorder when a synchronization word is lost, characterized in that the method comprises:

[0046] S1. The recorder data storage unit (CSMU, Crash Survivable Memory Unit) of the flight accident recorder is composed of N memory chips, each memory chip contains M memory segments, and the flight accident recorder is distributed according to the memory chips to enable the memory segments to store data in sequence, see Figure 2 , the distributed activation method of storage segments is as follows: when storing data, first activate the first storage segment of N storage chips for distributed storage in sequence, then activate the second storage segment of N storage chips for distributed storage in sequence, and so on, the order of storage activation storage segments is: DATA11→DATA21→DATA31→……→DATA(N-1)1→DATAN1→DATA12→DATA22→DATA32→……→DATA(N-1)2→DATAN2→DATA13→DATA23→DATA33→…DATAij…→DATA(N-1)3→DATAN3→……; the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M. The flight accident recorder stores data according to a fixed-structure data frame structure, each data frame includes four subframes, each subframe contains a number of words, each word includes 12 bits, and the first word of the data frame subframe is the synchronization word of the subframe.

[0047] S2. Read the data stored in the flight accident recorder in sequence. If the storage segment DATAij is damaged or broken, and the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, then use blank data to fill in and record. Due to the impact and damage of the accident, a certain segment of data in a storage chip in the recorder data storage component of the data recorder is damaged and lost (if the storage chip is partially damaged, the chip may be unrecognizable and unreadable). In this way, the loss of some data (especially the loss of synchronization words) will cause the data to be unable to be read normally by the tool; because the synchronization words of the recorded data are lost due to the destruction of the recorder data chip fragment, the original damaged data of the recorder cannot be directly deciphered and decoded to obtain the actual flight data record value. For this reason, the original recorded data of the damaged recorder needs to be reconstructed and repaired to ensure that it meets the data decoding format requirements. When reading, the damaged or broken data in the storage segment is spliced, filled in or repaired. For example: Figure 3 As shown, if DATAN1 and DATA31 are broken or damaged, blank data should be used to fill in the gaps and record them.

[0048] S3. Use the bit shift operation method to search and locate the subframe synchronization word of the data frame for the binary data stream read from the flight accident recorder, and divide and store the complete data frame data. Perform synchronization word repair and data verification processing on the remaining binary data stream.

[0049] If the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer bit by bit operation to sequentially obtain 12 bits of data and determine whether it is the synchronization word of the subframe, then the pointer moves back one bit to obtain 12 bits of data and determine whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found. Then, a synchronization word correction logic rule base is constructed based on the data frame structure, and the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed.

[0050] Preferably, the synchronization word correction logic rule base records the logic rules for correcting the synchronization word loss based on the front and back identification of the synchronization word. The synchronization word correction logic rule base stores the front and back structures of the data frame and subframe synchronization word, and uses the pointer to sequentially take 12 bits of data from the 0th bit of the binary data stream according to the bit operation and judge whether it is the synchronization word of the subframe, and then the pointer moves back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found, so that the synchronization word is first found, and then the synchronization word is located, and the front and back structure rules of the data frame and subframe synchronization word in the synchronization word correction logic rule base are called, and other word words with incomplete synchronization words and errors (incomplete synchronization words and partial errors in synchronization words are a difficulty in reading data in the flight accident recorder, and the existing technology cannot read them out and data loss will occur) are located based on the structure of the data frame, and the synchronization word information of the word words is aligned based on the synchronization word correction logic rule base for repair or correction. The present invention uses a pointer to sequentially obtain 12 bits of data from the binary data stream starting from bit 0 and determines whether it is a synchronization word of a subframe, and then moves the pointer back one bit to obtain 12 bits of data and determines whether it is a synchronization word of a subframe, so that a synchronization word and a word position with complete synchronization words can be found, and then based on the determined synchronization word and word position, the word position with incomplete or erroneous synchronization words is located by moving the word position of the pointer, and then the synchronization word is repaired or corrected, so that the data can be identified and quickly read out.

[0051] In addition to the situation where the synchronization word is incomplete, there is another serious situation where all the synchronization words are lost (for example, the synchronization words of each subframe in a data frame structure are all lost, and there is also data in the data frame. The existing method will report all errors when the tool reads it and cannot read and process it). In response to this serious problem, step S3 of the present invention also includes the following method: the synchronization word correction logic rule library stores the word word position verification correction rules of the synchronization word located by reference feature data, searches the reference feature data, logically verifies the word word position of the synchronization word, repairs the synchronization word, and records it in the log file. The reference feature data is a continuous and correlated feature. The reference feature data lists the date (DATE), UTC time, frame counter, super frame counter, etc. (based on UTC Time, frame counter and super frame counter and other specific and regular parameters are mutually verified, so as to realize the filling and repair of data frame synchronization word). Taking date (DATE) as an example, date (DATE) occupies several word positions according to year, month and day, and date (DATE) is continuous and related to each other; UTC time occupies several word positions according to hours, minutes and seconds, and UTC time is continuous and related to each other; super frame counter counts in a cycle of "0 to 15", and based on the data frame structure, the word position of the number recorded by the super frame counter can locate the position of the synchronization word; frame counter counts in sequence from 0 according to a regular pattern (such as 1 second of data), and based on the data frame structure, combined with the super frame counter, the position of the synchronization word can be located. The above is an enumeration of situations. Based on the data frame structure and other reference feature data, the word position of the synchronization word is located by a single or a combination of reference feature data, and the word position mutual verification correction rules in the synchronization word correction logic rule library are based on the synchronization word rules stored in the data frame structure to realize single or combined word position mutual verification positioning, and to realize the repair of the synchronization word located at the word position.

[0052] The reference feature data search method is as follows: start the reference feature data search from bit 0 in the binary data stream and verify it through continuity and relevance, then locate the word word position of the synchronization word based on the word word position mutual verification correction rule and repair the synchronization word. If the reference feature data cannot be found, the binary data stream is shifted right by one bit to search for the reference feature data and verify it through continuity and relevance, then locate the word word position of the synchronization word based on the word word position mutual verification correction rule and repair the synchronization word; the binary data stream continues to shift right until the synchronization word is repaired.

[0053] In some embodiments, a read data cache is set (since the selection of the data cache size will also affect the efficiency of data processing, in order to improve the efficiency of data processing, data greater than the length of a data frame needs to be read into the read data cache), and the synchronization word is patched or corrected in the read data cache, which can achieve more rapid synchronization word correction processing.

[0054] In some embodiments, each data frame is identified according to the above method based on the pointer, and the data gaps between adjacent data frames can be removed (research has found that: on the one hand, regardless of whether the flight accident recorder is damaged or not, there may be a random gap of indefinite length between adjacent data frames of the flight accident recorder during the process of recording actual flight data; on the other hand, each record word in a data subframe recorded by the flight accident recorder is stored without gaps, that is, each 12-bit record word is followed by the next 12-bit record word. Therefore, in the process of processing the binary data stream of the damaged recorder, the data gaps between adjacent data frames need to be removed to obtain the correct data), and recorded in the log file. In the process of computer processing of binary data stream, it is found through comparison research that the data gaps between two adjacent data frames mainly come from the following two aspects: ① In the process of synchronous word repair program processing, the bit mode is used for shift processing to accurately control the data stream, and the byte mode is used for data processing to ensure data processing efficiency. Therefore, when the data frame byte locator (Frame-Location) is used to locate the byte value of the starting position of a data frame relative to the file header. The starting position of the data frame is not always consistent with the starting position of the byte locator. It is necessary to determine through the program which bit of the byte locator the starting position of the data frame is, that is, the starting position of the data frame is shifted right by a certain number of bits (shift-right-bits) from the starting position of the data frame byte locator. ② In the process of computer processing binary data stream, a certain number of bytes of data blocks are read in turn, but when processing the actual data stream, it is found that there is usually an indefinite length of interval (block-gap) between two adjacent data blocks. The length of the interval between two adjacent data frames (Bits) = (Frame-Location(i)*8+shift-right-bits(i))-(Frame-Location(i-1)*8+shift-right-bits(i-1)), see Figure 6 .

[0055] Finally, all stored data are decoded; all data of the patched, corrected or / and repaired synchronization words are stored, and data are output using a byte-by-byte data processing method.

[0056] Embodiment 3

[0057] This embodiment is identical to Embodiment 1 and Embodiment 2 except for the following technical contents. The difference lies in that a repair processing model is constructed for patching or correcting the loss of synchronization words. The repair processing model includes a synchronization word correction logic rule base. The synchronization word correction logic rule base stores word bit mutual verification correction rules.

[0058] See also Figure 7 As shown, this embodiment takes "each data frame includes four subframes, each subframe contains 512 words, and each word includes 12 bits" as an example. The data in each column of each row is the position of a certain data frame (the number of bytes relative to the file header position, the bit offset position), the synchronization word value, the decoded flight date, UTC time, the frame counter value, the super frame counter value, the gap value with the next adjacent data frame, etc. found through the data frame synchronization word search shift algorithm (that is, using the bit shift operation method). The data frame synchronization word at the "99882014" byte position relative to the file header is incomplete (marked in yellow). The data frame can be judged as valid data and can be repaired through the numerical consistency of UTC time, frame counter and super frame counter. After replacing "0X844" and "0X840" with "0XA47" and "0XDB8" respectively through the algorithm, the data of the data frame can be obtained through the subsequent data decoding. If the data frame synchronization word is not repaired, the frame data will be discarded during decoding, which will cause valid data loss, which is not conducive to the investigation and analysis of the cause of civil aviation flight accidents. Figure 8 , Figure 8 The data output algorithm is shown taking a data frame of 512 words as an example.

[0059] Embodiment 4

[0060] A data repair system for a flight accident recorder in the event of synchronization word loss includes a flight accident recorder, a data reading module, a synchronization word search module, a storage module and a decoding device. The recorder data storage component of the flight accident recorder is composed of N storage chips, each storage chip contains M storage segments, and the flight accident recorder performs distributed activation of the storage segments according to the storage chips to store data in sequence. The flight accident recorder stores data according to a fixed-architecture data frame structure, each data frame includes four subframes, each subframe contains a number of word words, each word word includes 12 bits, and the first word word of the subframe of the data frame is the synchronization word of the subframe. The data reading module reads the data stored in the flight accident recorder in sequence. If the storage segment DATAij is read to be damaged or broken, and the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, blank data is used to fill in the gaps and record. See. Figure 2, the method of distributed enabling storage segments is as follows: when storing data, first enable the first storage segment of N storage chips for distributed storage in sequence, and then enable the second storage segment of N storage chips for distributed storage in sequence, and so on. The order of storage startup storage segments is: DATA1 1→DATA21→DATA31→……→DATA(N-1)1→DATAN1→DATA12→DATA22→DATA32→……→DATA(N-1)2→DATAN2→DATA13→DATA23→DATA33→…DATAij..·→DATA(N-1)3→DATAN3→……; the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M. Due to the impact and damage of the accident, a certain segment of data in a storage chip in the data storage component of the data recorder is damaged and lost (if the storage chip is partially damaged, the chip may be unrecognizable and unreadable). The loss of some data (especially the loss of synchronization words) will cause the data to be unable to be read normally by the tool; since the synchronization words of the recorder data are lost due to the destruction of the chip fragment, the original damaged data of the recorder cannot be directly deciphered and decoded to obtain the actual flight data record value. Therefore, it is necessary to reconstruct and repair the original recorded data of the damaged recorder to ensure that it meets the data decoding format requirements. When reading, the damaged or damaged data in the storage fragment is spliced, supplemented or repaired. For example: Figure 3 As shown, if DATAN1 and DATA31 are broken or damaged, blank data should be used to fill in the gaps and record them.

[0061] like Figure 4 , Figure 5As shown, the synchronization word search module uses a bit shift operation method to search and locate the synchronization word of the subframe of the data frame for the binary data stream read from the flight accident recorder, and divides and stores the complete data frame data. The synchronization word search module has a synchronization word correction module inside, and the synchronization word correction module has a synchronization word correction logic rule base. The synchronization word correction module performs synchronization word repair and data verification processing on the remaining binary data stream. The method is as follows: if the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer to operate bit by bit and 12 bits of data are taken in sequence and it is judged whether it is the synchronization word of the subframe, and then the pointer is shifted back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found. Then, a synchronization word correction logic rule base is constructed based on the data frame structure, and the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed. In this way, the synchronization word is first found, and then the synchronization word is located, and the front and back structure rules of the data frame and subframe synchronization word in the synchronization word correction logic rule library are retrieved. Based on the structure of the data frame, other word words with incomplete synchronization words or errors (incomplete synchronization words or partial errors in synchronization words are a difficulty in reading data in the flight accident recorder, and the existing technology cannot read them out and data loss will occur) are located, and the synchronization word information of the word word is aligned based on the synchronization word correction logic rule library for repair or correction. The present invention uses the pointer to sequentially take 12 bits of data from bit 0 of the binary data stream and judge whether it is the synchronization word of the subframe, and then the pointer moves back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, so that the synchronization word and word word position with complete synchronization words can be found, and then based on the determined synchronization word and word word position, the word word position with incomplete synchronization words or errors is located by moving the word word position of the pointer, and then the synchronization word is repaired or corrected, so that the data can be identified and quickly read out. The synchronization word correction logic rule base stores mutual verification correction rules for locating the word word of the synchronization word with reference to the characteristic data, searches the reference characteristic data and logically verifies the word word of the synchronization word and repairs the synchronization word, and records it in the log file. The reference characteristic data is a continuous and associated characteristic. The storage module is used for data storage, and the decoding device performs decoding processing.

[0062] An electronic device comprises: at least one processor and a memory connected to the at least one processor in communication. The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the data repair method of the flight accident recorder in the case of synchronization word loss of the present invention.

[0063] A storage medium stores a computer program, which, when executed by a processor, implements the steps of a data repair method for a flight accident recorder in the event of synchronization word loss of the present invention.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for restoring data of a flight accident recorder when a synchronization word is lost, characterized in that: The methods include: S1. The recorder data storage component of the flight accident recorder is composed of N memory chips, each memory chip contains M memory segments, and the flight accident recorder performs distributed activation of the memory segments according to the memory chips to sequentially store data. The flight accident recorder stores data according to a fixed-architecture data frame structure, each data frame includes four subframes, each subframe contains a number of words, each word includes 12 bits, and the first word of the data frame subframe is the synchronization word of the subframe; S2. Read the data stored in the flight accident recorder in sequence. If the storage segment DATAij is damaged or broken, and the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, blank data is used to fill the gap and record it; S3. Use the bit shift operation method to search and locate the subframe synchronization word of the data frame for the binary data stream read from the flight accident recorder, and divide and store the complete data frame data; perform synchronization word repair and data verification processing on the remaining binary data stream: If the synchronization word is lost, the binary data stream is taken from bit 0 using the pointer to operate bit by bit to sequentially obtain 12 bits of data and determine whether it is the synchronization word of the subframe, then the pointer is moved back one bit to obtain 12 bits of data and determine whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found; then a synchronization word correction logic rule base is constructed based on the data frame structure, the synchronization word correction logic rule base records the logic rules for correcting the synchronization word loss based on the synchronization word identified before and after, the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed; Finally, all stored data are decoded.

2. The method for restoring data of a flight accident recorder in the event of a synchronization word loss according to claim 1, characterized in that: Step S3 also includes the following method: the synchronization word correction logic rule base stores mutual verification correction rules for locating the word position of the synchronization word with reference to the feature data, searches the reference feature data and logically verifies the word position of the synchronization word and repairs the synchronization word, and records it in a log file, and the reference feature data is a continuity and correlation feature.

3. The method for restoring data of a flight accident recorder in the event of a synchronization word loss according to claim 2, characterized in that: The reference feature data search method is as follows: start the reference feature data search from bit 0 in the binary data stream and verify it through continuity and association, then locate the word bit of the synchronization word based on the word bit mutual verification and correction rule and repair the synchronization word; if the reference feature data cannot be found, the binary data stream is shifted right by one bit to search for the reference feature data and verify it through continuity and association, then locate the word bit of the synchronization word based on the word bit mutual verification and correction rule and repair the synchronization word; the binary data stream continues to shift right until the synchronization word is repaired.

4. The method for restoring data of a flight accident recorder in the event of a synchronization word loss according to claim 1, characterized in that: All data of all patched, corrected or / and repaired synchronization words are stored and data output is performed using a byte-by-byte data processing method.

5. The method for restoring data of a flight accident recorder in the event of a synchronization word loss according to claim 1 or 2, characterized in that: In step S3, a read data buffer area is set to perform synchronization word correction processing.

6. The method for restoring data of a flight accident recorder in the event of a synchronization word loss according to any one of claims 1 to 2, characterized in that: In step S3, data gaps between adjacent data frames are removed and recorded in a log file.

7. A data recovery system for a flight accident recorder in the event of synchronization word loss, characterized in that: The invention comprises a flight accident recorder, a data reading module, a synchronization word search module, a storage module and a decoding device. The recorder data storage component of the flight accident recorder is composed of N storage chips, each storage chip contains M storage segments, the flight accident recorder performs distributed activation of the storage segments according to the storage chips to sequentially store data, the flight accident recorder stores data according to a fixed-architecture data frame structure, each data frame includes four subframes, each subframe contains a number of word words, each word word includes 12 bits, and the first word word of the subframe of the data frame is the synchronization word of the subframe; the data reading module reads the data stored in the flight accident recorder in sequence, if the storage segment DATAij is read to be broken or damaged, the storage segment DATAij is the i-th storage chip and the j-th storage segment, 1≤i≤N, 1≤j≤M, then blank data is used for splicing and filling and recording; the synchronization word search module reads the binary data read by the flight accident recorder The data stream adopts a bit shift operation method to search and locate the synchronization word of the subframe of the data frame, and the complete data frame data is divided and stored; the synchronization word search module has a synchronization word correction module inside, and the synchronization word correction module has a synchronization word correction logic rule base, and the synchronization word correction module performs synchronization word repair and data verification processing on the remaining binary data stream, and the method is as follows: if the synchronization word is lost, the binary data stream is taken from bit 0 using a pointer to operate bit by bit to sequentially take 12 bits of data and judge whether it is the synchronization word of the subframe, then the pointer is shifted back one bit to take 12 bits of data and judge whether it is the synchronization word of the subframe, until the synchronization word of the subframe is found; then a synchronization word correction logic rule base is constructed based on the data frame structure, and the synchronization word correction logic rule base records the logic rules for correcting the loss of synchronization words based on the synchronization word recognition before and after, and the missing synchronization word in the data frame is repaired or corrected based on the synchronization word correction logic rule base, and a log file of synchronization word repair and correction records is constructed; The synchronization word correction logic rule base stores mutual verification correction rules for locating the word position of the synchronization word with reference to the feature data, searches for the reference feature data, logically verifies the word position of the synchronization word, repairs the synchronization word, and records it in a log file. The reference feature data is a continuous and associative feature; the storage module is used for data storage, and the decoding device performs decoding processing.

8. An electronic device, characterized in that: include: at least one processor; And a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the method as described in any one of claims 1 to 6.

9. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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