Double-track absolute position detection method and system, computer equipment and storage medium

Abstract

The invention provides a double-track absolute position detection method and system, computer equipment and a storage medium, and the method comprises the steps: detecting a to-be-detected object through a double-track magnetic railing ruler, enabling the to-be-detected object to be connected with a reading head, enabling the reading head to move along with the to-be-detected object, and enabling the reading head to read the to-be-detected object when the to-be-detected object linearly moves relative to the double-track magnetic railing ruler. Incremental magnetic track information of the incremental coding magnetic track is read through an incremental coding reading head; a level signal is output through a plurality of switch position detection chips in an absolute coding reading head based on the polarity of an absolute coding magnetic track position closest to the switch position detection chips, and absolute magnetic track information is determined according to the level signal; and performing combined calculation according to the incremental magnetic track information and the level signal to obtain a double-magnetic-track absolute position detection result. According to the method, the defect that an existing incremental displacement sensor needs to make a zero position again or search the zero position after being powered off or restarted is overcome, and the application scene of non-contact displacement detection is expanded.

Description

Technical Field

[0001] This invention belongs to the field of displacement measurement technology, specifically relating to a method, system, computer equipment, and storage medium for detecting the absolute position of dual magnetic tracks. Background Technology

[0002] Non-contact displacement detection technology using anisotropic magnetoresistive sensors and magnetic scales with appropriate pole or magnetic distances is relatively mature and has been widely used in fields such as linear displacement measurement of linearly moving objects. The sensor is fixed to the moving object to be measured and moves with it on a pre-fixed magnetic scale, thereby realizing absolute displacement detection within one pole distance. When the number of pole or magnetic distances crossed is measured by software, displacement measurement with a range exceeding one pole or magnetic distance can be performed, which can then be used for relative displacement detection.

[0003] However, during actual continuous measurements, the device under test continues to operate while the sensor is powered off, and the transpolar distance value accumulates and changes. When the sensor is powered back on, the actual transpolar distance value differs from the value before the power outage. This necessitates "zeroing" or "finding" operations to correct the transpolar distance value, affecting normal equipment operation and making it difficult to meet the requirements of scenarios with high demands for the continuity and reliability of absolute position information, resulting in poor applicability. Summary of the Invention

[0004] To address the issue of poor applicability of existing non-contact displacement detection technologies, this invention provides a dual-track absolute position detection method, system, computer equipment, and storage medium.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A dual-track absolute position detection method uses a dual-track magnetic grating ruler to detect the object under test. The dual-track magnetic grating ruler includes an incremental encoding reading head and an absolute encoding reading head. The absolute encoding reading head is an array of switch position detection chips composed of multiple switch position detection chips. The object under test is connected to both the incremental encoding reading head and the absolute encoding reading head. When the object under test moves linearly relative to the dual-track magnetic scale, the incremental track information of the incremental coded track of the dual-track magnetic scale is read by the incremental coded reading head; each switch position detection chip senses the polarity of the magnetic pole at the position of the switch position detection chip on the absolute coded track of the dual-track magnetic scale, and outputs a level signal according to the polarity. The incremental magnetic track information and the level signal are combined and calculated to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

[0006] Optionally, the dual-track absolute position detection method provided by the present invention further includes: The level signal is converted from analog to digital to obtain the position feature code. The pole pitch number of the incremental coded track is determined according to the position of the position feature code in the decoding array. The decoding array is a set of position feature codes of the absolute coded track, and the elements in the decoding array are arranged according to a preset order. Based on the incremental track information, the positioning is subdivided within one pole pitch length of the incremental coded track to obtain the subdivided positioning result. Based on the subdivided positioning result and the pole pitch number, the absolute position detection result of the dual tracks is determined.

[0007] Optionally, the dual-track absolute position detection method provided by the present invention further includes: The level signal is converted into a binary number, and the position feature code is obtained by arranging the binary numbers in order according to the physical position of the corresponding switch position detection chip in the switch position detection chip array.

[0008] Optionally, the dual-track absolute position detection method provided by the present invention further includes: The period length of the absolute coding track is determined based on the pole pitch of the incremental coding track and the measured length of the absolute coding track. The number of switch position detection chips n in the switch position detection chip array is determined based on the period length and the measured length of the absolute coding track. A binary pseudo-random number sequence is constructed based on the number n of switch position detection chips, where the period length of the binary pseudo-random number is 2. n -1; continuously copy an n-bit binary number from a binary pseudo-random number sequence of a period length to generate an element in the decoded array; The binary numbers in the binary pseudo-random number sequence are shifted forward and the shifted binary numbers are added to the end of the binary sequence to obtain the shifted binary pseudo-random number sequence. The binary numbers corresponding to the number of bits are copied from the shifted binary pseudo-random number sequence to generate the elements in the new decoding array. The decoding array is determined based on the generation order of multiple elements. The number of elements in the decoding array is equal to the period of the binary pseudo-random number, and each element is different.

[0009] Optionally, the dual-track absolute position detection method provided by the present invention further includes: The correspondence between binary numbers and magnetic field polarity is determined by the high and low output levels of the switch position detection chip when it is near magnetic fields of different polarities. Based on the correspondence between binary numbers and magnetic field polarity, the magnetic pole arrangement information of the absolute coded magnetic track is obtained by encoding consecutive multiple binary numbers in a binary pseudo-random number sequence, wherein the number of bits in the consecutive multiple binary numbers is less than or equal to the period length. The absolute coding track is constructed based on the magnetic pole arrangement information of the absolute code track.

[0010] Optionally, the dual-track absolute position detection method provided by the present invention further includes: The position feature code is compared with the elements in the decoding array, and the polar distance index is determined based on the index of the element in the decoding array, where the index of the element corresponds to the generation order.

[0011] Optionally, in the dual-track absolute position detection method provided by the present invention, the switch position detection chip array includes latch-inductive switch position detection chips arranged at equal intervals in the direction parallel to the absolute encoding track. The number of latch-inductive switch position detection chips is the same as the number of binary bits of the elements in the decoding array, and the distance between two adjacent latch-inductive switch position detection chips is equal to the pole pitch of the incremental encoding track.

[0012] This invention also provides a dual-track absolute position detection system, comprising: The incremental track reading module is used to read the incremental track information of the incremental coded track of the dual-track magnetic scale through the incremental coded reading head when the object under test moves linearly relative to the dual-track magnetic scale. The absolute magnetic track reading module is used to sense the polarity of the magnetic pole at the location of the switch position detection chip on the absolute coded magnetic track of the dual-track magnetic ruler by each switch position detection chip, and output a level signal according to the polarity. The position detection module is used to combine and calculate the incremental magnetic track information and the level signal to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

[0013] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement any of the steps of the dual-track absolute position detection method.

[0014] The present invention also provides a computer-readable storage medium storing a computer program that, when loaded by a processor, can execute any of the steps of the dual-track absolute position detection method.

[0015] The dual-track absolute position detection method provided by this invention has the following beneficial effects: The dual-track absolute position detection method provided by this invention synchronously reads the unique magnetic pole encoding sequence on the absolute coded track through a switch position detection chip array. It completes the reading and decoding of the absolute coded track without relying on any historical counting data before power failure. Combined with high-precision subdivided position information within a pole distance from incremental track information, it performs real-time merging and calculation, ultimately outputting a complete, high-resolution absolute position value, thus realizing the measurement of absolute position in dual-track systems. Regardless of how far the device under test has traveled during sensor power failure, the correct absolute position coordinates can be restored without "zeroing" or "zero-finding" operations after the sensor restarts, ensuring normal device operation. This solves the defect of existing incremental displacement sensors that require re-"zeroing" or finding the zero position after power failure or restart, expanding the application scenarios of non-contact displacement detection. Attached Figure Description

[0016] To more clearly illustrate the embodiments and design schemes of the present invention, the accompanying drawings required for this embodiment will be briefly described below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is one of the schematic diagrams of the dual-track absolute position detection method provided in the embodiments of the present invention; Figure 2 This is an example of a dual-track magnetic scale provided in an embodiment of the present invention; Figure 3 This is a second schematic diagram of the dual-track absolute position detection method provided in an embodiment of the present invention; Figure 4 This is the third schematic diagram of the dual-track absolute position detection method provided in the embodiments of the present invention; Figure 5 This is the fourth schematic diagram of the dual-track absolute position detection method provided in the embodiments of the present invention; Figure 6 This is the fifth schematic diagram of the dual-track absolute position detection method provided in the embodiments of the present invention; Figure 7 This is a schematic diagram of a dual-track absolute position detection system provided in an embodiment of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0019] Existing incremental displacement detection utilizes anisotropic magnetoresistive sensors, magnetic scales with appropriate pole or magnetic pitch, and software to measure displacements exceeding one pole or magnetic pitch. For example, k represents the number of pole pitches, p is the length of the pole or magnetic pitch, and s represents the measured absolute displacement within the pole pitch. and These are the initial values ​​for the transpolar moment and the initial values ​​for the absolute displacement within the polar moment, respectively. and These are the current values ​​of the transpolar moment and the current value of the absolute displacement within the polar moment, respectively. The displacement of the current position relative to the initial position is... ,in It is the result of continuous accumulation and can be used for relative displacement detection.

[0020] In practical continuous measurement applications, when Measurements can be performed correctly when the sensor can continuously accumulate and update data normally. However, if the sensor power supply is interrupted, then... It can correctly recover after the sensor power is restored and can still continue to perform correct measurements, such as those before the power outage. The data was saved, and since the measured device did not change position in the measurement direction during the sensor power failure, the data was recovered using the values ​​from before the power failure when the sensor was powered back on. The result The measured value matches the actual value, and the measurement data is accurate. However, in real-world scenarios, the device under test continues to operate even when the sensor is powered off. Cumulative change. The actual change occurs when the sensor regains power. The readings are different from those before the sensor was powered off. If it is necessary to continue measuring and outputting displacement with the initial position as zero, then correction is required. The value, also known as "zeroing" or "making change," inevitably leads to additional operations that require time and will certainly affect the normal operation of the equipment.

[0021] To address the aforementioned shortcomings, this invention provides a dual-track absolute position detection method. By reading and decoding the absolute track and subdividing the incremental track, it can achieve absolute position recognition within a certain physical length of the track. After the sensor restarts, there is no need to perform "zeroing" or "zero finding," thus expanding the application scenarios of non-contact displacement detection.

[0022] Example 1 This invention provides a dual-track absolute position detection method. The dual-track magnetic grating ruler includes an incremental encoding reading head and an absolute encoding reading head. The absolute encoding reading head is an array of switch position detection chips composed of multiple switch position detection chips. The object to be measured is connected to both the incremental encoding reading head and the absolute encoding reading head, as detailed below. Figure 1As shown, it includes: Step 11: When the object to be measured moves linearly relative to the dual-track magnetic scale, the incremental track information of the incremental track of the dual-track magnetic scale is read through the incremental coding reading head.

[0023] Step 12: Each switch position detection chip senses the polarity of the magnetic pole at the location of the switch position detection chip on the absolute coding magnetic track of the dual-code track magnetic ruler, and outputs a level signal according to the polarity.

[0024] Step 13: Combine and calculate the incremental magnetic track information and the level signal to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

[0025] First, a brief introduction to the dual-track magnetic scale used in this invention will be given. The magnetic scale consists of a steel backing, such as a carrier steel strip, a magnetic rubber strip, or a magnetic plastic strip. A protective layer can be applied to the surface of the magnetic rubber strip if needed. A dual-track magnetic scale, such as... Figure 2 As shown, a magnetic scale can be constructed by arranging incremental and absolute coded magnetic scales in parallel, or by arranging incremental and absolute coded tracks in parallel on the same steel back. For example, the magnetic rubber tape with relative or incremental coding is designated as track A, and the magnetic rubber tape with absolute coding is designated as track B. That is, a dual-track magnetic scale can be constructed by arranging a magnetic scale with track A and a magnetic scale with track B in parallel, or by having both tracks A and B arranged in parallel.

[0026] The reading head of the dual-track magnetic grating ruler consists of an incremental encoding reading head and an absolute encoding reading head, or an incremental track reading module integrating an incremental encoding reading head and signal processing circuitry, and an absolute track reading module integrating an absolute encoding reading head and signal processing circuitry. The incremental encoding reading head or incremental track reading module is denoted as reading head A, and the absolute encoding reading head or absolute track reading module is denoted as reading head B. Reading head A reads track A information, and reading head B reads track B information. The hardware and software of the position detection module process the information read by reading head A and reading head B respectively, and then synthesize the information to obtain the absolute position information. Once the relative positions of tracks A and B are fixed, the relative positions of reading heads A and B are fixed, or reading heads A and B are integrated into a single reading head; this invention is not limited in its approach.

[0027] In this invention, track A consists of N and S poles arranged alternately at equal intervals, with equal widths for the N and S poles. The pole pitch or magnetic moment P can be determined by the width of the N or S poles, or by the sum of half the width of the N pole and half the width of the S pole; this invention does not impose any limitations. Track B is also composed of N and S poles arranged in a regular pattern, and the widths of its N and S poles are integer multiples of the widths of the N and S poles in track A. That is, track B contains long N poles composed of consecutive N poles or long S poles composed of consecutive S poles. The length of each long N or long S pole is an integer multiple of the pole pitch in track A, and the starting position of the period in track B is aligned with or at a predetermined distance from the boundaries of the N and S poles in track A.

[0028] The arrangement of the N and S poles in tracks A and B can be represented by a binary sequence, with one bit representing the polarity within one pole pitch. For example, using 1 to represent the N pole and 0 to represent the S pole in binary, the N and S pole arrangement in track A is represented by a binary sequence of alternating 0s and 1s, such as "0101". In track B, the N and S poles for m consecutive pole pitches can be represented by m bits. For example, if m is 5, the pole arrangement in track B within 5 pole pitches is NSNNS, which can be represented by the binary sequence "10110". Furthermore, when using 0 to represent the N pole and 1 to represent the S pole, the "SNSN" arrangement in track A is represented by the binary sequence "1010", and the NSNNS arrangement in track B is represented by the binary sequence "01001".

[0029] Based on the above binary sequence representation, by using a suitable N / S pole arrangement order, the binary sequence can possess absolute encoding characteristics. That is, in a long N / S pole arrangement sequence, any short, consecutive N / S poles of a fixed number of bits are unique. Considering that the longest period of the binary sequence generated by an n-order or n-stage linear feedback shift register is... A single, consecutive n-bit binary number with a fixed position is unique within the longest-period binary sequence. Therefore, its absolute position within this longest-period binary sequence can be determined based on the n-bit binary number. When the N and S poles of the magnetic track are based on... When determining the binary representation of a given number of bits, the polarity of these n consecutive magnetic poles can be used to determine the polarity of these n consecutive magnetic poles. The specific location within a series of magnetic poles.

[0030] The longest period is The binary sequence can be a pseudo-random binary sequence (PRBS), an m-sequence, binary Gray code, or other types of absolute encoding. Since the longest period for an n-bit word length encoding is... Position, within a cycle When a consecutive n-bit binary number is extracted from a binary sequence, its value is unique. Therefore, once the consecutive n-bit binary numbers are determined, their positions in the binary sequence can be determined.

[0031] Based on this, according to the pre-defined correspondence between "1", "0" and the N and S poles, the... The binary sequence is encoded into a magnetic pole sequence, forming track B. For track B, after identifying the polarity of n consecutive magnetic poles within one cycle, the specific positions of these n poles within the cycle can be determined, i.e., their absolute positions within that cycle. The range of these positions is one pole moment or magnetic moment p. When it is necessary to determine the specific position within a pole moment, further refinement can be achieved using track A to determine the absolute position. For example, the tangent value can be calculated using sine and cosine signals related to the magnetic field position, and then the signal phase angle can be calculated. Using the relationship between the signal phase angle and the absolute position within a pole moment, the absolute position within a pole moment can be calculated. In practical applications, the phase angle and its tangent value can be discretized. For ease of calculation, it can be further amplified and rounded, and a data table can be created for subsequent lookup calculations.

[0032] Specifically, in the dual-track absolute position detection method provided by the present invention, the reading head detects the incremental track information and absolute track information of the parallel-arranged incremental coded track and absolute coded track. The position detection module electrically connected to the reading head collects the incremental track information and absolute track information and determines the incremental position information and absolute position information. Based on the incremental position information and absolute position information, the final absolute displacement detection result is determined, thereby realizing the dual-track absolute position detection function.

[0033] The dual-code-channel reading head can be composed of a fixedly connected reading head A and a reading head B, or it can be a reading head that integrates an absolute code-channel reading device and an incremental code-channel reading device. The reading head B includes a switch position detection chip that is sensitive to the magnetic field by using the Hall effect or magnetoresistive effect, such as a unipolar induction type switch position detection chip, a latching induction type switch position detection chip, and an all-polar induction type switch position detection chip.

[0034] Specifically, the operating logic of a unipolar inductive switch position detection chip is as follows: when a magnetic pole approaches the chip, the magnetic field strength generated at the chip is greater than the threshold, and the chip turns on. When the magnetic pole moves away from the chip, the magnetic field strength generated at the chip is less than the threshold, and the chip turns off. The operating logic of a latching inductive switch position detection chip is as follows: when a magnetic pole, for example, the S pole, approaches the chip, the chip turns on when the magnetic field strength generated at the chip is greater than the threshold, until another magnetic pole, for example the N pole, approaches the chip, and the magnetic field strength generated at the chip is greater than the threshold, and the chip turns off. This cycle continues until yet another different magnetic pole, for example the S pole, approaches the chip, and the magnetic field strength generated at the chip is greater than the threshold, and the chip turns on again, and so on. The operating logic of an omnipolar inductive switch position detection chip is as follows: when any magnetic pole approaches the chip, the magnetic field strength generated at the chip is greater than the threshold, and the chip turns on. When that magnetic pole moves away from the chip, the magnetic field strength generated at the chip is less than the threshold, and the chip turns off.

[0035] The dual-track absolute position detection method provided by this invention does not limit the switch position detection chip. Absolute track information can be acquired using multiple single-type switch position detection chips, or multiple different types of switch position detection chips can be used in combination. Considering that the output of the latch-inductive switch position detection chip is related not only to the magnetic field strength but also to the magnetic field polarity, a latch-inductive switch position detection chip is selected for acquiring the absolute track information. In this case, the latch-inductive switch position detection chip converts the detected absolute track information into a level signal and outputs it.

[0036] For example, multiple latching inductive switch position detection chips are arranged in an equally spaced array on a printed circuit board (PCB). The distance between two adjacent chips is equal to the pole distance P of track A. The multiple latching inductive switch position detection chips sense the magnetic poles near the chips and output level signals for the position detection module to determine the absolute position information. Furthermore, amplification, detection, and other electronic devices, as well as peripheral conditioning circuits, can be arranged on the PCB to realize the processing function of the chip output signals.

[0037] It is important to emphasize that, since the distance between two adjacent chips is equal to the pole pitch P of track A, the pole pitch P of track A needs to be greater than the physical dimension of the latch-type inductive switch position detection chip along the detection direction. Furthermore, the number of chips in the latch-type inductive switch position detection chip array corresponds to the number of chips in track B. The word length n of a 1-bit binary pseudo-random number sequence is equal to the series n of an m-sequence, for example, in Within a bit encoding period, the number of latching inductive switch position detection chips in the array is n.

[0038] In the dual-track absolute position detection method provided by the present invention, the latching inductive switch position detection chip can generate a level signal for sampling and calculation by the position detection module in the following manner: The magnetic poles on the absolute encoding track include the N pole and the S pole. The latching inductive switch position detection chip turns on and outputs a high-level signal when the S pole is close, and turns off and outputs a low-level signal when the N pole is close, and vice versa. It is important to emphasize that decoding can only be successful if the correspondence between the N and S poles, the high and low level signals, and the binary "1" and "0" correspondences are consistent with the magnetic pole encoding rules in track B.

[0039] The dual-track absolute position detection method provided in this application can output high-level or low-level signals based on the polarity and magnetic field strength of the nearest magnetic pole in the absolute coded track through an array of latching inductive switch position detection chips, thereby completing the reading and decoding of the absolute coded track. Combined with the incremental track information read by the incremental coded reading head, it realizes the measurement of the absolute position in the dual tracks, solving the defect of existing incremental displacement sensors losing the absolute zero position after power failure or restart, requiring recalibration or searching for the zero position, and expanding the application scenarios of non-contact measurement of magnetic scales.

[0040] Furthermore, the dual-track absolute position detection method provided by this invention includes a latching inductive switch position detection chip. The output of the latching inductive switch position detection chip is related not only to the magnetic field strength but also to the magnetic field polarity. It can output and stop output according to the magnetic poles, generating a level signal that fluctuates with the magnetic poles. This facilitates the position detection module to distinguish and generate binary sequences, ensuring the accuracy and convenience of signal processing in the dual-track absolute position detection system.

[0041] Specifically, each latching inductive switch position detection chip is replaced by two single-pole inductive switch position detection chips with different polarities, arranged perpendicular to the detection direction. They simultaneously detect the magnetic field polarity. When one chip outputs a high level, the corresponding magnetic field polarity is the magnetic pole that the chip can detect. In this way, magnetic field polarity detection is achieved by using two chips that respond to different magnetic pole polarities. Based on the correspondence between magnetic pole polarity and binary "0" and "1", a binary value or level value is output.

[0042] Based on the above embodiments, the dual-track absolute position detection method provided by the present invention, such as... Figure 3 As shown, step 13 includes: Step 131: Convert the level signal from analog to digital to obtain the position feature code. Determine the pole pitch number of the incremental coded track based on the position of the position feature code in the decoding array. The decoding array is a set of position feature codes of the absolute coded track, and the elements in the decoding array are arranged according to a preset order. Step 132: Based on the incremental track information, subdivide the positioning within one pole pitch length of the incremental coded track to obtain the subdivision positioning result. Determine the absolute position detection result of the dual tracks based on the subdivision positioning result and the pole pitch number.

[0043] Furthermore, in the dual-track absolute position detection method provided by the present invention, step 131 includes: Step 1311: Convert the level signal into a binary number, and arrange the binary numbers in order according to the physical position of the corresponding switch position detection chip in the switch position detection chip array to obtain the position feature code.

[0044] In the dual-track absolute position detection method provided by this invention, the position detection module includes an absolute reading processing unit that samples and processes the level signal acquired by the reading head B. The absolute reading processing unit samples the reading head B, acquires the level signal from the reading head B, and performs analog-to-digital conversion to generate an n-bit binary position feature code. For example, a threshold is determined based on the level value output by the latching inductive switch position detection chip. Level signals greater than the threshold are converted to binary 1, and level signals less than the threshold are converted to binary 0, generating a multi-bit binary number. Then, the absolute reading processing unit combines the current position feature code with its position order in the decoding array to generate the position sequence number of the current position feature code. Here, the position feature code is an element in the decoding array, and the element's sequence number is the position sequence number. The first digit of each element in the decoding array, arranged sequentially, constitutes the position sequence number. binary sequence, In the binary sequence of bits, each bit corresponds to a magnetic pole according to the rules, generating the magnetic pole arrangement order. The magnetic poles in track B are arranged according to this polarity order.

[0045] For example, the magnetic poles of track B are arranged according to a period of The binary sequence represents the position of the n latches. 1 corresponds to the source (S) pole, and 0 corresponds to the neutral (N) pole. The n latching inductive position detection chips in the reading head B output a high level when near the source pole and turn off when near the neutral pole. The absolute reading processing unit is electrically connected to the reading head B, samples the level signal, performs analog-to-digital conversion, and sequentially arranges the conversion results into an n-bit binary number. This generates an n-bit binary position feature code. The position of this feature code within a binary sequence with a period of n bits is then determined, and its position number is output. .

[0046] Because the dual-track absolute position detection method provided by this invention can perform binary conversion on the level signal, the generated multi-bit binary number has a fixed position in the binary sequence within a fixed period, thereby enabling absolute displacement detection. The binary conversion method simplifies the signal processing difficulty in the absolute displacement detection process, and the uniqueness of the multi-bit binary number ensures the accuracy of absolute displacement detection.

[0047] The dual-track absolute position detection method provided by this invention also includes a correspondence detection module that detects the correspondence between the level signal and the binary conversion relationship of track B. When the correspondence detection module detects a discrepancy between the level signal and the binary conversion relationship of track B, it performs a detection, which is then used by other modules in the absolute reading processing unit to correct errors and ensure consistency between the two.

[0048] For example, a latching inductive switch position detection chip outputs a high level when the S pole is close and turns off the output when the N pole is close. The signal level is converted to 1 when it is greater than a threshold and to 0 when it is less than the threshold. The magnetic poles of track B are arranged according to a periodic... The binary sequence is represented by bits. If 0 corresponds to the S pole and 1 corresponds to the N pole, the correspondence detection module determines that the binary conversion relationship between the level signal and track B is inconsistent. Then, other modules in the absolute reading processing unit, such as the binary number inversion module, invert the binary number after the analog-to-digital conversion of the level signal to determine the final binary sequence position number. .

[0049] Because the absolute reading processing unit in the dual-track absolute position detection system provided by this invention also has binary detection and error correction functions, it avoids the problem of absolute position recognition error when the level signal conversion and the correspondence between the binary numbers of the absolute encoded track do not match, thus ensuring the accuracy of dual-track absolute position detection.

[0050] Furthermore, the dual-track absolute position detection method provided by this invention can also achieve signal error correction through level conversion, for example, by adjusting the level signal through a level conversion circuit. When the correspondence detection module detects a mismatch between the level signal and the binary correspondence, the level signal is converted by a level conversion circuit located before the analog-to-digital conversion circuit, converting high level to low level and low level to high level. Subsequently, the analog-to-digital conversion circuit performs analog-to-digital conversion on the level-converted level signal to generate the error-corrected binary sequence position number. .

[0051] Because the dual-track absolute position detection system provided by this invention is also designed with a level conversion circuit, it can pre-convert the level signal before analog-to-digital conversion, thereby improving the error correction capability of the detection system and further ensuring the accuracy of dual-track absolute position detection.

[0052] Furthermore, the dual-track absolute position detection system provided by this invention can also achieve signal error correction through binary number inversion. When the correspondence detection module detects a mismatch between the level signal and the binary correspondence, the binary number inversion module, located after the analog-to-digital conversion circuit, inverts the binary sequence position number bit by bit, converting binary 0 to 1 and binary 1 to 0, thereby generating the error-corrected binary sequence position number. .

[0053] Because the dual-track absolute position detection method provided by this invention can invert the position number of the binary sequence bit by bit after analog-to-digital conversion, it improves the error correction capability of the detection system and further ensures the accuracy of dual-track absolute position detection.

[0054] Based on the above embodiments, the dual-track absolute position detection method provided by the present invention, such as... Figure 4 As shown, before step 12, the following steps are also included: Step 14: Determine the period length of the absolute coding track based on the pole pitch of the incremental coding track and the measured length of the absolute coding track. Determine the number of switch position detection chips in the switch position detection chip array based on the period length and the measured length of the absolute coding track.

[0055] Step 15: Construct a binary pseudo-random number sequence based on the number n of switch position detection chips, where the period length of the binary pseudo-random number is 2. n -1; continuously copy an n-bit binary number from a binary pseudo-random number sequence of a period length to generate an element in the decoded array.

[0056] Step 16: Shift the binary numbers in the binary pseudo-random number sequence forward and add the shifted binary numbers to the end of the binary sequence to obtain the shifted binary pseudo-random number sequence. Copy the binary numbers corresponding to the number of bits from the shifted binary pseudo-random number sequence to generate the elements in the new decoding array.

[0057] Step 17: Determine the decoding array based on the generation order of multiple elements. The number of elements in the decoding array is equal to the period of the binary pseudo-random number, and each element is different.

[0058] And, as Figure 5 As shown, after the decoder array is constructed, absolute encoded tracks can also be constructed in the following ways: Step 18: Determine the correspondence between the binary number and the magnetic field polarity based on the high and low output levels of the switch position detection chip when it is near magnetic fields of different polarities.

[0059] Step 19: Based on the correspondence between binary numbers and magnetic field polarity, obtain the magnetic pole arrangement information of the absolute coded magnetic track from the consecutive multiple binary numbers in the binary pseudo-random number sequence, wherein the number of bits in the consecutive multiple binary numbers is less than or equal to the period length.

[0060] Step 20: Based on the magnetic pole arrangement information of the generated absolute coding track, with each magnetic pole length being one pole pitch length, construct the absolute coding track and encode the binary number sequence in the absolute track.

[0061] Specifically, first, the pole pitch p of the incremental encoding track is selected, and the number n of switch position detection chips is determined in combination with the measurement distance h, as shown in formula (1): (1) In order to reduce the size of the reading head and the number of switch position detection chips, this embodiment selects the minimum value of n that satisfies formula (1) as the number of switch position detection chips. Then, based on the selected value of n, a generation cycle of... The binary pseudo-random number, or m-sequence, or binary Gray code. Where the period is... The binary pseudo-random numbers are arranged sequentially in a period. A sequence of 12 bits of binary numbers is processed, with each copy of n bits consecutively copied from the first to the nth bit as an element of the decoding array, starting from the first element and proceeding sequentially. After copying... The entire binary sequence of bits is shifted forward by one bit, and the shifted-out first bit is added to the last bit or the first bit. The process of copying and shifting continues, looping. After that, The binary sequence of bits is the same as the initial one, and the decoded array contains... n-bit binary numbers, and Each of the n-bit binary numbers is unique. At this point, the first generated n-bit binary number is the decoded array element with index 1, and all elements in the decoded array are sorted according to this index.

[0062] Once the decoding array is determined, in this embodiment, the correspondence between binary "1" and "0" and magnetic field polarity can be selected based on the output level of the switch position detection chip when different polarity magnetic fields are close together. According to this correspondence, based on... A periodic binary sequence of bits generates the magnetic field information of the absolute code channel. Each bit of the binary number corresponds to a magnetic field of length p, generating... The magnetic field information of the length is used to manufacture the absolute code track of the dual-code magnetic grating.

[0063] Based on the above embodiments, the dual-track absolute position detection method provided by the present invention, such as... Figure 6As shown, step 131 also includes: Step 1312: Compare the position feature code with the elements in the decoding array one by one according to the sequence number, and determine the polar distance sequence number based on the sequence number of the elements in the decoding array, wherein the sequence number of the elements corresponds to the generation order.

[0064] Specifically, in the dual-track absolute position detection method provided by this invention, decoding can be achieved in the following manner: The switch position detection chip array is placed close to the absolute encoding magnetic track, with the chip array orientation parallel to the extension direction of the magnetic grating ruler. Each chip reacts to the polarity of the approaching magnetic pole, outputting a high level or turning off the output depending on the polarity. Then, analog-to-digital conversion is performed on the level data: the level data output by each chip in the switch position detection chip array is read sequentially, compared with a threshold, and converted into binary 1 or 0, arranged sequentially as the position feature code of the current position. Finally, decoding and positioning are performed: the data element with the same position feature code as the current position is searched in the decoding array, and the index of this data element in the array is determined. To decode the positioning value, that is, to position the current position L at the position starting from the initial position of the cycle. Within a minimum pole moment or magnetic moment, for example Then it returns to reading the level data and performs decoding in a loop.

[0065] Specifically, in the dual-track absolute position detection method provided by this invention, incremental track information is subdivided by an incremental reading processing unit that samples and processes the data from the reading head A. When the reading head A outputs incremental track information based on the magnetic field induction within the current magnetic moment, the incremental reading processing unit, electrically connected to the reading head A, subdivides the incremental track information to generate position data within the current magnetic moment. This refers to incremental location information.

[0066] At this point, the output of the position detection module includes both the binary sequence position number and the position number. This also includes position data within the current magnetic moment. It can calculate the current location data. And then in Absolute positioning is achieved within the specified range. For example, if P is 5mm and n is 7, then... Within a certain length range, absolute positioning can be achieved using the dual-track absolute position detection system provided by this invention, thereby realizing absolute displacement detection.

[0067] Because the dual-track absolute position detection method provided by this invention can refine the incremental track information collected by the reading head A, thereby clarifying the relative position within the current magnetic moment, and generate the absolute displacement detection result by combining the position feature code sequence number determined by the absolute reading processing unit, the accuracy of dual-track absolute position detection is further guaranteed.

[0068] Based on the above implementation, the switch position detection chip array includes latch-inductive switch position detection chips arranged at equal intervals in the direction parallel to the absolute encoding track. The number of latch-inductive switch position detection chips is the same as the number of binary bits of the elements in the decoding array, and the distance between two adjacent latch-inductive switch position detection chips is equal to the pole pitch of the incremental encoding track.

[0069] Specifically, the number of latching inductive switch position detection chips is determined by the encoding rules and cycle length of the absolute coding track, which is the length of the binary code of the position feature. Within one cycle, the binary code corresponding to n consecutive poles of a given pole pitch length on the absolute code track constitutes the position feature. This position feature is unique within one cycle, and the cycle length is... Polar distance.

[0070] Example 2 Based on implementation 1, the present invention also provides a complete example of a dual-track absolute position detection system: The dual-track absolute position detection system includes parallel-arranged incremental coded tracks and absolute coded tracks, a reading head, and a position detection module. The reading head includes reading head A for acquiring track information of the incremental coded tracks and reading head B for acquiring track information of the absolute coded tracks. The position detection module samples data from reading head A and processes the data to generate position data within the current magnetic moment. The incremental reading processing unit samples the reading head B and processes the data to generate a binary sequence position number. The absolute reading processing unit. The reading head B includes a PCBA with an array of latch-inductive switch position detection chips, the number of which corresponds to the absolute encoding track. Within a cycle, the word length (n) remains consistent. This is used to detect the magnetic pole closest to the chip in the absolute coding track and output a level signal. Different magnetic poles output or disable the level signal. The absolute readout processing unit distinguishes the level signals based on a threshold and represents them as binary numbers. An n-bit binary track information code is generated sequentially, and then the n-bit binary number is searched for... The position number of the binary sequence of bits This allows the specific position of the track information code within the track cycle to be determined. Furthermore, the absolute reading processing unit uses a correspondence detection module to compare the level signal with the corresponding binary number of the track B pole. If a mismatch is detected, the level signal is adjusted using a level conversion circuit located before the analog-to-digital conversion circuit. Based on the adjusted level signal, a binary sequence position number is generated. Alternatively, the binary sequence position number can be determined by setting a binary number inversion module after the analog-to-digital converter circuit. Perform bit-by-bit inversion to obtain the position number of the error-corrected binary sequence. Simultaneously, the incremental reading processing unit acquires the incremental track information of reading head A and performs subdivision processing to generate position data within the current magnetic moment. Finally, the dual-track absolute position detection system is based on and Determine the absolute position and generate absolute displacement detection results.

[0071] In the dual-track absolute position detection system provided by this invention, the absolute reading processing unit can be integrated into the reading head B, and the incremental reading processing unit can be integrated into the reading head A; alternatively, reading head A and reading head B can be integrated into one unit and electrically connected to the position detection module; or the position detection module can be housed within the integrated reading head and encapsulated as a single unit. This invention does not impose any limitations. Furthermore, those skilled in the art can integrate a display module within the integrated reading head with the integrated reading processing module to display position data based on actual application needs, and can expand the functionality of the display module, such as setting zero position, calculating speed, and acceleration.

[0072] The physical length for absolute position identification is limited by the length of the maximum periodic code and the length of the pole pitch in the coded track. When the pole pitch in the coded track remains constant, as the length of the maximum periodic code increases, those skilled in the art can increase the number of chips in the chip array based on actual needs, thereby lengthening the physical dimension of the reading head along the chip array direction, thus ensuring the identification or testing effect. This invention will not elaborate further.

[0073] Because the dual-track absolute position detection system provided by this invention arranges a latching inductive switch position detection chip array, it realizes the reading and decoding of absolute encoded tracks such as PRBS or m-sequences, and combines it with an incremental reading processing unit to subdivide the incremental tracks, thus achieving... The identification of the absolute position within the physical length of the magnetic track corresponding to the maximum period code avoids the defect of the incremental magnetic track being difficult to identify the absolute position. It solves the problem that the absolute zero position of the existing incremental displacement sensor is lost after power failure or restart, and needs to be recalibrated or searched for. This expands the application scenarios of non-contact measurement by magnetic scales.

[0074] Example 3 The present invention also provides a specific example of dual-track position detection: When measuring and performing absolute positioning within a 300mm range, a 5mm pole pitch track is selected, and the pseudo-random sequence length needs to be greater than [a certain value]. Considering The condition of being greater than 60 is met, therefore the word length of the pseudo-random sequence is determined. .

[0075] When n is 6, a six-level feedback polynomial is used. A 6-level m-sequence is obtained, such as "100000100001100010100111101000111001001011011101100110101011111", with a length of 63 bits. Each bit corresponds to an N-pole or S-pole of one pole pitch length. The length of the track formed by this sequence is: For a 63-bit m-sequence, six consecutive codewords are extracted sequentially from left to right to form a positional feature code. Each positional feature code is unique. These positional feature codes are arranged and numbered according to the extraction order, with each positional feature code having a unique serial number. The specific position of the positional feature code within the aforementioned m-sequence can then be determined based on the serial number, and the direction of movement can be known from the change in the serial number. The positional feature codes are arranged sequentially from right to left or left to right, with each positional feature code corresponding to a unique serial number; this invention does not impose any limitation on this. For example, six consecutive codewords are extracted sequentially from right to left to form a positional feature code, each of which is unique. These positional feature codes are arranged and numbered according to the extraction order, with each positional feature code having a unique serial number.

[0076] The positional feature codes extracted from the aforementioned m-sequence from left to right are shown in formula (2): in, This represents the k-th position feature code, for example, the 63rd position feature code is " 110000".

[0077] Encoding track B according to the aforementioned 6-level m-sequence, a dual-track magnetic grating is fabricated. Six latching inductive switch position detection chips are arrayed on the PCB along the detection direction, meaning the chips are distributed parallel to and uniformly along the detection direction, with the distance between adjacent chips equal to the pole spacing. Combined with peripheral circuitry, this forms an absolute track reading module. The absolute track reading module is located directly above track B of the dual-track magnetic grating. It simultaneously reads and processes the output signals from the six latching inductive switch position detection chips. Following the N and S poles corresponding to 1 and 0 in track B encoding, each latching inductive switch position detection chip's output signal is encoded as either 1 or 0 and arranged sequentially. This forms a 6-bit binary position feature code decoded by the reading head B for its current position on track B. By examining the array formed by the sequential arrangement of all position feature codes, the sequence number of the position feature code decoded by the reading head B can be determined. For example, when the decoded position feature code is "000010", the sequence number can be found in the decoded array. In other words, if track B is divided into equal intervals with a pole pitch as the interval for one cycle, the aforementioned position feature code can locate the third interval. Considering that the position feature code will not change when the position of the reading head B relative to track B changes within a pole pitch range, the reading head A can also read the track information of track A to achieve subdivision within the pole pitch. Thus, based on the index of the position feature code in the array, the specific position of track B detected by the reading head B in the 6-level m sequence can be calculated, realizing absolute displacement detection based on a dual-track magnetic grating ruler and a dual-track reading head.

[0078] Example 4 This invention also provides a dual-track absolute position detection system, such as... Figure 7 As shown, it includes: The incremental track reading module 201 is used to read the incremental track information of the incremental coded track of the dual-track magnetic scale through the incremental coded reading head when the object under test moves linearly relative to the dual-track magnetic scale.

[0079] The absolute magnetic track reading module 202 is used to sense the polarity of the magnetic pole at the location of the switch position detection chip on the absolute coded magnetic track of the dual-track magnetic ruler by each switch position detection chip, and output a level signal according to the polarity.

[0080] The position detection module 203 is used to combine and calculate the incremental magnetic track information and the level signal to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

[0081] Specifically, the dual-track absolute position detection system provided by this invention consists of a dual-track magnetic scale, detection hardware, and detection calculation software. The detection hardware includes an incremental track reading module, an absolute track reading module, and a position detection module. The incremental track reading module reads the incrementally encoded magnetic field information from the dual-track magnetic scale. The absolute track reading module contains a switch position detection chip array, which outputs the magnetic field information of the absolute track as electrical level information. The position detection module executes the detection calculation software, converts the electrical level information into binary numbers, arranges them to obtain a position feature code, and searches for the element index corresponding to the position feature code in the decoding array. This element index is used as the pole distance index of the current incremental track. Simultaneously, the magnetic field information obtained by the incremental track reading module is subdivided to determine the subdivided position within the current pole distance, thereby determining the current position value. This position value is the absolute position within the range of the dual-track magnetic scale. The vector pointing from the initial position to the current position is the current displacement, thus realizing absolute position measurement based on the dual-track magnetic scale.

[0082] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory. The processor executes the computer program to implement the steps in the embodiments of the dual-track absolute position detection method. Specific implementation methods can be found in the method embodiments, and will not be repeated here.

[0083] Furthermore, the present invention also provides a non-transitory computer-readable storage medium containing instructions, on which a computer program is stored. For example, a memory containing instructions that can be executed by a processor of a computer device to perform the above-described method. For example, the non-transitory computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc. When the computer program is executed by the processor, it can implement the steps in the embodiments of the dual-track absolute position detection method. Specific implementation methods can be found in the method embodiments, which will not be repeated here.

[0084] Those skilled in the art will understand that embodiments of the present invention can provide methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0085] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0086] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0087] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0088] It should be noted that the above specific embodiments enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. Therefore, although the present invention has been described in detail in this specification and embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention; and all technical solutions and improvements that do not depart from the spirit and scope of the present invention are covered within the protection scope of the present invention patent. No reference numerals in the claims should be construed as limiting the scope of the claims. Any simple variations or equivalent substitutions of technical solutions that can be readily obtained by those skilled in the art within the scope of the technology disclosed in the present invention are within the protection scope of the present invention.

Claims

1. A dual-track absolute position detection method, characterized in that, The method involves detecting the object under test using a dual-track magnetic scale. The dual-track magnetic scale includes an incremental encoding reading head and an absolute encoding reading head. The absolute encoding reading head is an array of switch position detection chips composed of multiple switch position detection chips. The object under test is connected to both the incremental and absolute encoding reading heads. The method includes the following steps: When the object under test moves linearly relative to the dual-track magnetic scale, the incremental track information of the incremental coded track of the dual-track magnetic scale is read through the incremental coding reading head; each of the switch position detection chips senses the polarity of the magnetic pole at the position of the switch position detection chip on the absolute coded track of the dual-track magnetic scale, and outputs a level signal according to the polarity. The incremental magnetic track information and the level signal are combined and calculated to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

2. The dual-track absolute position detection method according to claim 1, characterized in that, The incremental track information and the level signal are combined and calculated to obtain the dual-track absolute position detection result of the object under test, including: The level signal is converted from analog to digital to obtain a position feature code. The pole pitch number of the incremental coded track is determined according to the position of the position feature code in the decoding array. The decoding array is a set of position feature codes of the absolute coded track, and the elements in the decoding array are arranged according to a preset order. Based on the incremental track information, the incremental coded track is subdivided and positioned within one pole distance length to obtain a subdivided positioning result. Based on the subdivided positioning result and the pole distance number, the absolute position detection result of the dual track is determined.

3. The dual-track absolute position detection method according to claim 2, characterized in that, The step of converting the level signal from analog to digital to obtain the position feature code includes: The level signal is converted into a binary number, and the binary number is arranged in order according to the physical position of the switch position detection chip corresponding to each level signal in the switch position detection chip array to obtain the position feature code.

4. The dual-track absolute position detection method according to claim 3, characterized in that, Before the object under test moves linearly relative to the dual-track magnetic grating ruler, the method further includes: The period length of the absolute coding track is determined based on the pole pitch of the incremental coding track and the measured length of the absolute coding track. The number n of switch position detection chips in the switch position detection chip array is determined based on the period length and the measured length of the absolute coding track. A binary pseudo-random number sequence is constructed based on the number n of the switch position detection chips, wherein the period length of the binary pseudo-random number is 2. n -1; continuously copy n bits of binary numbers in the binary pseudo-random number sequence of one period length to generate an element in the decoded array; The binary numbers in the binary pseudo-random number sequence are shifted forward and the shifted binary numbers are added to the end of the binary sequence to obtain the shifted binary pseudo-random number sequence. The binary numbers corresponding to the number of bits are copied from the shifted binary pseudo-random number sequence to generate new elements in the decoding array. The decoding array is determined according to the generation order of the multiple elements, wherein the number of elements in the decoding array is equal to the period of the binary pseudo-random number, and the elements are all different.

5. The dual-track absolute position detection method according to claim 4, characterized in that, After determining the decoding array based on the plurality of said elements, the method further includes: The correspondence between binary numbers and magnetic field polarity is determined by the high and low output levels of the switch position detection chip when it is near magnetic fields of different polarities. Based on the correspondence between the binary number and the magnetic field polarity, the magnetic pole arrangement information of the absolute coded magnetic track is obtained by encoding consecutive multiple binary numbers in the binary pseudo-random number sequence, wherein the number of bits in the consecutive multiple binary numbers is less than or equal to the period length. The absolute coding track is constructed based on the magnetic pole arrangement information of the absolute code track.

6. The dual-track absolute position detection method according to claim 4, characterized in that, Determining the pole-moment number of the incremental coded track based on the position of the location feature code in the decoding array includes: The position feature code is compared with the elements in the decoding array, and the polar distance number is determined based on the index of the element in the decoding array, wherein the index of the element corresponds to the generation order.

7. The dual-track absolute position detection method according to claim 2, characterized in that, The switch position detection chip array includes latch-inductive switch position detection chips arranged at equal intervals in the direction parallel to the absolute encoding track. The number of latch-inductive switch position detection chips is the same as the number of binary bits of the elements in the decoding array, and the distance between two adjacent latch-inductive switch position detection chips is equal to the pole pitch of the incremental encoding track.

8. A dual-track absolute position detection system, characterized in that, The object under test is detected by a dual-track magnetic scale, which includes an incremental encoding reading head and an absolute encoding reading head. The absolute encoding reading head is an array of switch position detection chips composed of multiple switch position detection chips. The object under test is connected to the incremental encoding reading head and the absolute encoding reading head, including: The incremental track reading module is used to read the incremental track information of the incremental coded track of the dual-track magnetic scale through the incremental coded reading head when the object under test moves linearly relative to the dual-track magnetic scale. The absolute magnetic track reading module is used to sense the polarity of the magnetic pole at the location of the switch position detection chip on the absolute coded magnetic track of the dual-track magnetic grating ruler by each of the switch position detection chips, and output a level signal according to the polarity. The position detection module is used to combine and calculate the incremental magnetic track information and the level signal to obtain the absolute position detection result of the dual magnetic tracks of the object under test.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the dual-track absolute position detection method according to any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is loaded by the processor, it is able to execute the steps of the dual-track absolute position detection method according to any one of claims 1-7.

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