Multi-sensor position measurement system
By using segmented switching detection of Hall sensors and magnetoresistive sensors in modular components, combined with calculation by the processing unit, the problems of low accuracy and complex initialization in traditional position measurement systems are solved, achieving high-precision and low-cost position measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HIWIN MIKROSYST
- Filing Date
- 2022-06-20
- Publication Date
- 2026-07-31
AI Technical Summary
Traditional position measurement systems suffer from low accuracy, low resolution, complex initialization processes, and high costs, making them difficult to apply in high-precision industrial fields.
Modular components are used, including primary Hall sensors and secondary high-precision magnetoresistive sensors. By switching detection in segments and combining it with the processing unit to calculate the carrier position, the initialization process is simplified.
It improves position measurement accuracy, simplifies the initialization process, reduces system costs, and is suitable for high-precision industrial applications.
Smart Images
Figure CN117308755B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to position measurement technology, and more particularly to a multi-sensor position measurement system. Background Technology
[0002] Traditional position measurement systems typically use Hall effect sensors for detection, but their disadvantages include low accuracy (approximately ±0.25 mm) and low resolution, which limits the application of Hall effect sensors in high-precision industrial fields.
[0003] Moreover, initialization is usually performed to ensure the accuracy of the measurement position, but if there are too many sensors and carriers, the initialization process will be quite complicated.
[0004] Therefore, how to simplify the initialization process and improve accuracy while reducing the cost of the measurement system will be a question that relevant industry players need to consider. Summary of the Invention
[0005] Therefore, the main objective of this invention is to provide a multi-sensor position measurement system that can accurately measure the position of a carrier.
[0006] Therefore, in order to achieve the above objectives, the multi-sensor position measurement system of the present invention mainly has modular components, including two primary sensors and two secondary high-precision sensors. High-precision detection is achieved by segmented switching between the primary sensors and the secondary high-precision sensors.
[0007] Specifically, the system further includes a base, a carrier, a first signal array, and a second signal array, wherein the carrier is movable relative to the base. Each of the signal arrays is disposed on the carrier spaced apart from each other and has a plurality of sequentially arranged signal source elements, and the signal period of the second signal array is shorter than the signal period of the first signal array, thereby improving measurement accuracy.
[0008] The modular components further include a processing unit for receiving signals detected by the sensors and calculating the position of the carrier, and a first state sensor for generating reference signals, connecting measurement results between other sensors, and identifying the orientation of the vehicle.
[0009] In one embodiment, the first and second sensors are primary sensors, such as Hall sensors, for position feedback, while the third and fourth sensors are secondary high-precision sensors, such as heterogeneous magnetoresistive sensors, for modifying the position measured by the primary sensors and determining the commutation phase of the motor current.
[0010] In one embodiment, when the first state sensor is activated, it is located at the end of the measurement range of the first sensor, and the amplitude signal of the second sensor is higher than a predetermined threshold.
[0011] In one embodiment, the processing unit calculates the results measured by the sensors using a weighting function to obtain a reference signal.
[0012] In one embodiment, the processing unit compares the amplitude signals of each Hall sensor with a predetermined threshold and analyzes the state of the state sensor based on the reference signal, as a basis for estimating the direction of movement of the carrier.
[0013] In one embodiment, the measurement module further includes a second state sensor located at the end of the measurement range of the measurement module, and has a marker unit disposed on the carrier and a sensitive element disposed on the base for sensing the signal generated by the marker unit.
[0014] When the second state sensor is activated, it is located at the end of the measurement range of the second sensor, and the amplitude signal of the first sensor is lower than a predetermined threshold.
[0015] In one embodiment, a mechanical displacement related to the signal period is defined by the phase change between the first signal array and the second signal array on the carrier, for the processing unit to identify the carrier.
[0016] In one embodiment, the measurement range of the measurement module is divided into a positive repositioning region and a negative repositioning region from a starting position, and the automatic repositioning direction of the carrier is estimated based on the measurement results of these sensors. In one embodiment, the modular component further includes a stator, and the two Hall sensors and the two magnetoresistive sensors are respectively located on both sides of the stator. When the first signal array is located above the stator, the processing unit begins to perform homing operations.
[0017] In summary, this invention solves the problems of low accuracy, difficulty in identifying the carrier, and complex initialization calculations in traditional measurement systems by utilizing modular components. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the first embodiment of the present invention.
[0019] Figure 1A These are top views, side views, and front views showing the specific positional relationships of the components in the first embodiment of the present invention.
[0020] Figure 2 This is a schematic diagram of the internal components of a Hall sensor.
[0021] Figure 3This is a schematic diagram of the internal components of a magnetoresistive sensor.
[0022] Figure 4 This is a schematic diagram of the signals sensed by each sensor in the first embodiment of the present invention.
[0023] Figure 5 This is a schematic diagram of the relevant signals and positions in the initialization procedure of the first embodiment of the present invention.
[0024] Figure 6 It is a continuation Figure 5 A schematic diagram of the absolute region is further defined.
[0025] Figure 7 This is the second embodiment of the present invention, indicating that the number of modular components is two.
[0026] Figure 8 These are the top view, side view, and front view of the third embodiment of the present invention.
[0027] Figure 9 This is a schematic diagram of the third embodiment of the present invention.
[0028] Figure 10 This is a schematic diagram of the encoding principle of the second state sensor according to the third embodiment of the present invention.
[0029] Figure 11 This is a schematic diagram of the fourth embodiment of the present invention, showing the state of increasing the step size.
[0030] Figure 12 This is a schematic diagram of the fifth embodiment of the present invention regarding the positioning identification between two modular components.
[0031] Figure 13 This is a schematic diagram of the carrier recognition principle in the fifth embodiment of the present invention. Detailed Implementation
[0032] First, it should be noted that the terms such as "first," "second," etc., used in this case are only for the purpose of distinguishing components and have no technical significance in themselves. They will be omitted when there is no need to distinguish them.
[0033] like Figures 1 to 6 As shown, the multi-sensor position measurement system provided in the first embodiment of the present invention mainly includes a base, a motion part, and a modular component 60.
[0034] The base is a structure of length that serves as the foundation for the construction of other components. For example, in a linear motor, the base is the stator mount.
[0035] The moving part has a first signal array 10, a carrier 11, and a second signal array 12. The carrier 11 has a length and is movably located on one side of the base. The signal arrays 10 and 12 are spaced apart from each other on the carrier 11. In this embodiment, a linear motor is used as an example. The first signal array 10 is a magnet array on the mover. In addition to interacting with the magnetic field generated by the coil in the stator to cause linear displacement of the moving part, the magnets also serve as signal sources. The second signal array 12 can be a magnetic ruler or optical ruler arranged in a regular pattern using conventional techniques such as magnetic, electrical, or optical non-contact signal sources. In this embodiment, it is a magnetic ruler composed of a plurality of magnetic elements 101, such as magnets. Thus, each signal array 10 and 12 has a magnetic period T1 and T2, respectively, and extends along the long axis of the carrier 11, with predetermined lengths L1 and L2, respectively. T2 is less than T1 to improve detection accuracy, and L1 is at least a multiple of two T2.
[0036] In addition, each signal array 10, 12 has a spacing DHA between them to reduce the mutual influence of magnetic fields. For example, the DHA can be 60 mm, but it is not limited to this.
[0037] The modular component 60 has a preset width of step size DM and includes a measurement module 20, a processing unit 30, a drive unit 40, and a stator 50. The stator 50 is disposed on the base and interacts with the magnetic field of the first signal array 10, driving the carrier 11 to displace relative to the base. The processing unit 30 receives the information sensed by the measurement module 20, calculates the position information of the carrier 11, and feeds it back to the drive unit 40. The drive unit 40 then controls the power supply to the stator 50, such as by commutating the current.
[0038] The measurement module 20 has a first sensor 21, a second sensor 22, a third sensor 23, a fourth sensor 24 and a first state sensor 25. Each of the first and second sensors is a Hall sensor 21 and 22, which are primary sensors and are located at both ends of the long axis of the base. The stator 50 is positioned between these Hall sensors 21 and 22 to sense the magnetic field change of the first signal array 10 as the basis for the position feedback of the carrier 11. The spacing DH of each Hall sensor 21 and 22 is an integer multiple of the magnetic period T1.
[0039] Each Hall sensor 21 and 22 has at least two sensing elements H1 and H2, respectively, which are arranged along the X-axis at a distance of T1 / 4, as shown below. Figure 2 As shown, when the carrier 11 moves along the X-axis, the signals output by each sensing element are proportional to the cosine and sine differential signals Cos1+ and Sin1+, respectively, i.e., U Cos1 = U ampl1cos(α1), U Sin1 = U ampl1 sin(α1), where α1 is the signal phase, U ampl1 The amplitude signal, and the sub-period position x1, are calculated by the processing unit 30 according to formula 1: x1 = (T1 / 360°)α1 = (T1 / 360°)·atan2(U Sin1+ U Cos1+ ),(Formula 1) Here, atan2(y, x) is the arctangent function in the four quadrants.
[0040] Since the positions of Hall sensors 21 and 22 relative to stator 50 are known, they can be directly switched to another set of high-precision measurement sensors after current commutation, without the need for the drive unit 40 to take any action to find the current commutation phase, which is quite convenient.
[0041] The third and fourth sensors, 23 and 24, are magnetoresistive sensors, serving as secondary high-precision sensors. For example, they could be anisotropic magnetoresistive sensors used to detect motor current commutation during system initialization and to sense changes in the magnetic field of the second signal array 12. Each magnetoresistive sensor 23 and 24 is located at both ends of the base along its long axis, with the stator 50 positioned between these magnetoresistive sensors 23 and 24.
[0042] Each magnetoresistive sensor 23 and 24 includes at least four sensing elements (S1, S2, S3, and S4), arranged along the X-axis at a T2 / 8 interval. When the carrier 11 moves along the X-axis, the signals output by each sensing element are proportional to the half-cycles of the differential sine and cosine signals Cos2+, Sin2+, Cos2-, and Sin2-, respectively, exhibiting anisotropic magnetoresistive effect. U Cos2+ = U ampl2 cos(α2), U Sin2+ = U ampl2 sin(α2), U Cos2- = -U ampl2 cos(α2), U Sin2- = -U ampl2 sin(α2), Where α2 is the signal phase, U ampl2 It is an amplitude signal.
[0043] Processing unit 30 uses the arctangent trigonometric function to estimate the sub-period position x2 in half a magnetic period T2: x2 = (T2 / 720°)·α2 = (T2 / 720°)·atan2(U Sin2+ - U Sin2- ),(U Cos2+ - U Cos2- )(Formula 2) Furthermore, this invention simplifies the switching procedure between signal arrays 10 and 12 by ensuring that the spacing DA between magnetoresistive sensors 23 and 24 is an integer multiple of the magnetic period T1. T1 is an integer multiple of T2, for example, T1 = 30 mm, T2 = 10 mm. L1 is an integer multiple of T1 and equal to the step size DM. L2 is at least two T2s, as shown in the following relationship: L2 = L1 + 2·T2 (Formula 3) like Figure 4 As shown, the sub-cycle phase 231 of the third sensor 23 is synchronized with the phase 211 of the first sensor 21. For example, when phase 211 is equal to 0, phase 231 is also equal to zero. Furthermore, in Figure 6, a label 13 marks the current position of the carrier 11 to indicate the status of each sensor at the position.
[0044] When the first amplitude signal 212 of the first sensor 21 is higher than a predetermined first threshold 213, the first sensor 21 becomes active, and the first threshold 213 is half of the maximum first amplitude signal 212.
[0045] When the carrier 11 moves along the X-axis, the third sensor 23 can detect the carrier 11 earlier than the first sensor 21 because the length L2 of the second signal array 12 is greater than the length L1 of the first signal array 10.
[0046] The first amplitude signal 212 and the second amplitude signal 222 of signals A1 and A2 measured by each Hall sensor 21 and 22 are calculated as follows: (Formula 4) exist Figure 4 In the first amplitude signal 212, the first threshold 213 is equal at positions 214 and 215, and the distance between the two positions 214 and 215 is used as the measurement range 270 of the first sensor 21.
[0047] The third amplitude signal 232 and the fourth amplitude signal 242 of signals A3 and A4 measured by magnetoresistive sensors 23 and 24 respectively are calculated as follows: (Formula 5) When the third amplitude signal 232 of the third sensor 23 is higher than a predetermined third threshold 233, and the first amplitude signal 212 of the first sensor 21 is higher than the first threshold 213, the third sensor 23 is switched to the active state, and the starting position 214 is used as the basis for position synchronization between the first signal array 10 and the second signal array 12.
[0048] The position synchronization refers to the calculation of the new sub-cycle position (x2') according to Formula 6 during the switching from the first signal array 10 to the second signal array 12, which is used for motor current commutation and high-precision position feedback.
[0049] x2' = (T2 / 2)·round(x1 / x2) + x2, (Formula 6) Here, round(x) is a function that finds the smaller integer.
[0050] exist Figure 4 In this process, the second amplitude signal 222 is equal to the second threshold 223 at positions 224 and 225, and the distance between the two positions 224 and 225 is used as the measurement range 271 of the second sensor 22 and the fourth sensor 24, and the measurement range 292 of the measurement module 20 is between positions 214 and 225.
[0051] When the carrier 11 enters or leaves the measurement ranges 270 and 271 of each Hall sensor 21 and 22, signal distortion occurs due to end effects caused by changes in the magnetic field and because the sensitive elements H1 and H2 are not completely covered by the first signal array 10. Therefore, in order to continuously and smoothly measure the position of the carrier 11, the measurement ranges of each Hall sensor 21 and 22 are made to have an overlapping region 291, which is located between these positions 215 and 224, and its range is at least one magnetic cycle T1.
[0052] To further reduce the impact of end effect, the present invention defines a joining region 290 using a digital joining method, as shown in Formula 7. When the carrier 11 is located in the joining region 290, the digital joining method uses a first weighting function 280 and a second weighting function 281 to sum the phases 211 and 221 of each Hall sensor 21 and 22, respectively.
[0053] Furthermore, the phases 211 and 221 of each Hall sensor 21 and 22 are connected before the system switches to the second signal array 12, while the phases 231 and 241 of each magnetoresistive sensor 23 and 24 are connected after the system switches to the second signal array 12.
[0054] like Figure 4 As shown, the phase 221 of the second sensor 22 estimates the junction region 290 using junction phase thresholds 226 and 227, with each junction phase threshold 226 and 227 being 60° and 120° respectively, and positions 2261 and 2271 being the start and end points of the junction region 290 respectively.
[0055] In the junction region 290, the digital connection phase 282 is calculated as follows: α1 join = α1 21 ·W1(α1 22 ) + α1 22 ·W2(α1 22 ), (Formula 7) Where, α1 join α121 is the digital connection phase 282 of each Hall sensor 21, 22, and α1 is the phase 211 of the first sensor 21. 22 It is the phase 221 of the second sensor 22, W1(α1) 22 ) is the first weighting function 280, W2(α1) 22 ) is the second weighting function 281, for example, the weighting function is Figure 4 The linear inverse function in the junction region 290.
[0056] Then, use Formula 8 to calculate the digital connection phase 283 of magnetoresistive sensors 23 and 24.
[0057] α2 join = α2 23 ·W1(α1 22 ) + α2 24 ·W2(α122), (Formula 8) Where, α2 join The digital connection phase 283, α2 of each magnetoresistive sensor 23, 24 23 It is the phase 231, α2 of the third sensor 23. 24 It is phase 241 of the fourth sensor 24.
[0058] The first state sensor 25 can be an optical switch sensor used for position estimation, such as reference signal generation, connecting measurement results from other sensors, and identifying the homing direction. It has a first marker unit 251 and a first sensing element 253. The first marker unit 251 is disposed on the carrier 11 adjacent to the first signal array 10, and its length L3 must be greater than the distance between positions 2261 and 2271. The first sensing element 253 is disposed on the base and is used to sense the signal generated by the first marker unit 251. When the carrier 11 enters the detection range of the first state sensor 25, particularly between positions 2261 and 2271, and in conjunction with the positional relationship between the first sensing element 253 and the first marker unit 251, the first state sensor 25 can become active.
[0059] Based on the aforementioned sensor arrangement, the junction region 290 is defined by status signal 252, phase 221, junction phase thresholds 226 and 227, and first threshold 213 and second threshold 223.
[0060] Next, in order to establish an incremental absolute measurement system, a homing process, also known as an axis initialization run, must be performed. An initial position 272 is set on the movement path as a reference for triggering the switching, and the drive unit 40 drives the carrier 11 to move to the initial position 272 to determine the absolute position of the carrier 11 and obtain a reference signal.
[0061] exist Figure 4 In this process, the initial position 272 is obtained based on the first threshold 213, the second threshold 223 of each Hall sensor 21, 22, and the initial position threshold 228 of the second sensor 22. The initial position threshold 228 is 150°.
[0062] Considering the positional relationship between the first state sensor 25, the engagement area 290, and the initial position 272, the length L3 of the first marking unit 251 must be greater than the distance between position 2261 and the initial position 272.
[0063] In addition, to ensure the uniqueness of the step size DM of the modular component 60, the first state sensor 25 is activated only in the last cycle 2111 of the first sensor 21, as shown in Figure 6. The cycle 2111 refers to the point where the signal A1 becomes less than the threshold 213 during the movement of the carrier 11.
[0064] Then, when the phase 221 of the first sensor 21 is between 0° and 60°, the state signal 252 becomes active.
[0065] The length L3 of the first marking unit 251 is equal to the magnetic period T1 to ensure the uniqueness of the period 2111.
[0066] exist Figure 5 In this process, the measurement range 292 is divided into a positive homing region 293 and a negative homing region 294 based on the starting position 272, and the automatic homing direction is determined by the states of the first state sensor 25 and each Hall sensor 21, 22. If the carrier 11 is located at the starting position 272, and the phase 221 of the second sensor 22 is equal to the initial position threshold 228, and the state signal 252 is in an active state, then no homing is required.
[0067] When the carrier 11 is in the positive homing region 293, zeroing correction must be performed in the positive direction of the X-axis, and the following conditions must be met: the status signal 252 is in an active state, the phase 221 is lower than the initial position threshold 228, for example, the phase 221 is between 30° and 150°, and the signal A1 is higher than the amplitude threshold 213; or, the status signal 252 is not in an active state, and the signal A1 is higher than the amplitude threshold 213.
[0068] When the carrier 11 is located in the negative homing region 294, homing must be performed in the negative direction of the X-axis.
[0069] exist Figure 4 In this process, processing unit 30 determines the homing direction by adding or subtracting digital connection phases 282 and 283. Specifically, if the homing direction is positive, two magnetic periods T1 (-720°) are subtracted from digital connection phase 282; if the homing direction is negative, two magnetic periods T1 (+720°) are added to digital connection phase 282. Then, when driving unit 40 receives a corrected phase 285 calculated by processing unit 30, it can decode the position and estimate the homing direction.
[0070] Furthermore, if the length L3 of the first marking unit 251 is less than two magnetic cycles T1, and the state signal 252 is in an active state, the present invention can perform absolute position estimation without performing repositioning correction.
[0071] like Figure 6 As shown, the activation range in the status signal 252 is used to further distinguish an absolute region 295 in the measurement range 292, so as to calculate the absolute position and the automatic return direction.
[0072] If carrier 11 is located in absolute region 295 and state signal 252 is in an active state, then homing is not required. The absolute position is calculated as follows: When signal A1 is higher than threshold 213: x abs= (T1 / 360°)(α1 join - α home ) (Formula 9) Where, x abs It is the standard absolute phase 286, α home The initial position threshold is 228, for example, α. home =150°; When signal A1 is not higher than threshold 213: x abs = (T1 / 360°)(α1 join - α home ) + T1 (Formula 10) If the carrier 11 is located in the positive homing region 293 and the state signal 252 is inactive, and the signal A1 is higher than the threshold 213, a zeroing correction must be performed in the positive direction of the X-axis.
[0073] If the carrier 11 is located in the negative homing region 294, homing must be performed in the negative direction of the X-axis.
[0074] Furthermore, the present invention uses a discontinuous stator permanent magnet linear synchronous motor as power. Automatic return direction calculation is only performed when the first signal array 10 is above the stator 50 and the overlapping area of the two is at least one magnetic cycle T1, so as to avoid the motor being unable to provide sufficient driving force to the carrier.
[0075] like Figure 7 As shown, in order to continuously measure the position of the carrier 11, the second embodiment of the present invention can configure more modular components 60 along the moving path of the carrier 11, and the initial position 272 between two adjacent modular components 60 is equal to the step size DM of a single modular component 60, so that the two have overlapping measurement areas, and the two adjacent modular components 60 are electrically connected by a fieldbus 71, and then connected to a motion controller 70 for controlling the movement of the carrier.
[0076] The motion controller 70 analyzes the received standard absolute phase 287 of the adjacent modular components 60 and performs a homing calculation using one of the modular components 60. Then, if the received standard absolute phase 287 is less than four magnetic periods T1, i.e., +1440°, the modular component 60 that is ranked first on the X-axis is selected; otherwise, the modular component 60 that is ranked last on the X-axis is selected.
[0077] When the carrier 11 is located between two adjacent modular components 60, two situations may occur: one is that both modular components 60 can perform the return to their original position, but not in the negative direction; the other is that the carrier 11 cannot move due to insufficient overlap area. Therefore, to solve the aforementioned problems, such as Figures 8 to 10The figure shown is the third embodiment of the present invention. Its main difference from the first embodiment is the addition of a second state sensor 26, which can be an optical switch sensor. It has a second sensitive unit 263 for sensing the first marker unit 251 or another independent second marker unit 261, and is placed at the end of the measurement range 292 so that the processing unit 30 knows that the measurement range 292 is about to end, and further distinguishes an end region 296 in the measurement range 292 by the activation range in the state signal 262.
[0078] When the carrier 11 is located in the end region 296, the status signal 262 of the second status sensor 26 is activated. The processing unit 30 adds four magnetic cycles T1, i.e. +1440°, to the digital connection phase 282 for correction to obtain a standard absolute phase 287, and sends it to the drive unit 40, and then transmits it to the motion controller 70 via the linear field bus 71.
[0079] like Figure 11 As shown, the fourth embodiment of the present invention differs from the first embodiment mainly in that a set of magnets 101 is added to the first signal array 10 to change the step size DM, and the overlapping area 291 also changes accordingly. Therefore, the present invention uses the first state sensor 25 as an aid to ensure the uniqueness of the overlapping area 291.
[0080] Figure 12 The fifth embodiment disclosed follows the fourth embodiment by using two modular components 60 to identify the direction of automatic regression, and the modular component 60 arranged later must be zeroed in the positive direction of the X-axis.
[0081] During the repositioning process, this invention further utilizes sensor redundancy technology to automatically identify different carriers 11. Figure 13 In this process, a mechanical shift (d12) is defined by the phase change between each signal array 10, 12. To avoid affecting the calculation results in Formula 6, the mechanical shift d12 is 0.5 mm, and the mechanical shifts d12 of different carriers must differ by 0.05 mm for distinguishability. The second sensor 22 or the fourth sensor 24 can measure the mechanical shift d12, while the motion controller 70 stores the mechanical shifts d12 of all carriers 11 for decoding.
[0082] In this example, the initial position 272 in the homing procedure is used as the measurement position of the identification carrier to avoid different measurement results and reduced accuracy caused by different reference positions.
[0083] The above description describes the preferred embodiments of the present invention and the technical principles applied thereto. For those skilled in the art, any obvious changes such as equivalent transformations or simple substitutions based on the technical solutions of the present invention, without departing from the spirit and scope of the present invention, shall fall within the protection scope of the present invention.
Claims
1. A multi-sensor position measurement system, characterized by include: One base; A carrier (11) is movable relative to the base; A first signal array (10) and a second signal array (12) are disposed on the carrier (11) spaced apart from each other, and each has a plurality of sequentially arranged signal source elements, wherein the signal period of the second signal array (12) is shorter than the signal period of the first signal array (10); and A modular component (60) includes a measurement module (20) and a processing unit (30), wherein the measurement module (20) includes: A first sensor (21) and a second sensor (22) are disposed separately on the base for sensing the signal of the first signal array (10); A third sensor (23) and a fourth sensor (24) are disposed separately on the base for sensing the signal of the second signal array (12); and A first state sensor (25) has a first marking unit (251) disposed on the carrier (11) and a first sensitive element (253) disposed on the base, for sensing the signal generated by the first marking unit (251); The processing unit (30) receives the signals detected by the first sensor (21), the second sensor (22), the third sensor (23), and the fourth sensor (24) and calculates the position of the carrier (11); The first sensor (21) and the second sensor (22) correspond to the first signal array (10) and serve as primary sensors to provide position feedback; The third sensor (23) and the fourth sensor (24) correspond to the second signal array (12) and serve as secondary high-precision sensors to correct the positions measured by the first sensor (21) and the second sensor (22) and improve the position measurement accuracy. When the first state sensor (25) is activated, it is located at the end of the measurement range of the first sensor (21), and the second amplitude signal (222) of the second sensor (22) is higher than a predetermined second threshold (223); The processing unit (30) calculates the measurement results of the first sensor (21), the second sensor (22), the third sensor (23), and the fourth sensor (24) respectively using a weighting function to obtain a reference signal; The processing unit (30) compares the first amplitude signal (212) and the second amplitude signal (222) of the first sensor (21) and the second sensor (22) with a predetermined first threshold (213) and a second threshold (223) based on the reference signal, and analyzes the state of the first state sensor (25) as a basis for estimating the moving direction of the carrier (11).
2. The multi-sensor position measurement system of claim 1, wherein The measurement module (20) further includes a second state sensor (26), located at the end of the measurement range of the measurement module (20), and has a second marker unit (261) disposed on the carrier (11) and a second sensitive element (263) disposed on the base, for sensing the signal generated by the second marker unit (261).
3. The multi-sensor position measurement system of claim 2, wherein When the second state sensor (26) is activated, it is located at the end of the measurement range of the second sensor (22), and the first amplitude signal (212) of the first sensor (21) is lower than a predetermined first threshold (213).
4. The multi-sensor position measurement system of claim 1, wherein A mechanical displacement (d12) related to the signal period is defined by the phase change between the first signal array (10) and the second signal array (12) on the carrier (11) for the processing unit (30) to identify the carrier (11).
5. The multi-sensor position measurement system as described in claim 1, characterized in that, The measurement range of the measurement module (20) is divided into a positive repositioning region (293) and a negative repositioning region (294) based on a starting position (214), and the automatic repositioning direction (200) of the carrier (11) is estimated by the measurement results of the first sensor (21), the second sensor (22), the third sensor (23), and the fourth sensor (24).
6. The multi-sensor position measurement system as described in claim 1, characterized in that, The modular component (60) further includes a stator (50), and the first sensor (21) and the second sensor (22) are located on both sides of the stator (50), and the third sensor (23) and the fourth sensor (24) are located on both sides of the stator (50). When the first signal array (10) is located above the stator (50), the processing unit (30) begins to perform the homing operation.