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CN-121994448-A - Method and system for measuring rolling angle of magnetic suspension model based on trapezoidal marker line

CN121994448ACN 121994448 ACN121994448 ACN 121994448ACN-121994448-A

Abstract

The invention discloses a trapezoid mark line-based magnetic suspension model roll angle measurement method and a trapezoid mark line-based magnetic suspension model roll angle measurement system. The system comprises a pose measuring sensor and a trapezoid mark line. The trapezoid mark line is a closed trapezoid ring which is adhered to the mass center of the model in a surrounding mode, the width value of the trapezoid mark line parallel to the axis of the model is in monotone linear change, and the trapezoid mark line is in a trapezoid shape with unequal bottom edges in a geometric unfolding state. During measurement, the linear array CCD scans the surface of the suspension model and detects pixel serial numbers corresponding to two edges imaged by the trapezoid marking lines, the rolling angle of the suspension model can be calculated by combining a preset geometric relationship according to the difference value of the pixel serial numbers corresponding to the two edges, and the axial position of the suspension model can be calculated by the average value of the pixel serial numbers of the two edges. On the premise of not changing a hardware system, the invention realizes the integrated measurement of the rolling gesture and the axial position by only changing the sign line configuration and the resolving method, and has the advantages of good compatibility, low cost and high measurement instantaneity.

Inventors

  • DOU FENGSHAN
  • YANG BIAO
  • LONG ZHIQIANG
  • YANG HUANG
  • LIU ZIYU
  • PENG ZENGDE

Assignees

  • 中国人民解放军国防科技大学

Dates

Publication Date
20260508
Application Date
20260408

Claims (8)

  1. 1. The method for measuring the rolling angle of the magnetic suspension model based on the trapezoid mark line is characterized by comprising the following steps of: S1, firstly setting the rolling angle of a suspension model (3) to be 0 degree in an initial state, acquiring pixel serial numbers corresponding to two edge ends of a and b opposite to each other along the axial direction of the suspension model (3) imaged by a trapezoid mark line (2) on a CCD photosensitive system (12) in the initial state, and recording the difference value of the pixel serial numbers of the two pixel serial numbers ; S2, after the suspension model (3) rolls, under the current measurement state, acquiring pixel serial numbers corresponding to two opposite edge ends a and b, which are opposite to each other in the axial direction of the suspension model (3), of a trapezoidal mark line (2) imaged on a CCD photosensitive system (12) under the current state, and recording the difference value of the pixel serial numbers of the two pixel serial numbers in the S2 ; S3, according to the pixel serial number difference value 、 Calculating to obtain the roll angle of the suspension model (3) in the current measurement state 。
  2. 2. The trapezoid mark line-based rolling angle measurement method of a magnetic suspension model according to claim 1, wherein the pixel sequence number difference in S1 The formula of (2) is as follows: ; Wherein, the 、 When the two pixel serial numbers are respectively in an initial state, the two opposite edges of b and a imaged by the trapezoid mark line (2) on the CCD photosensitive system (12) correspond to each other; The pixel serial number difference value in the S2 The formula of (2) is as follows: ; Wherein, the 、 After the suspension model (3) rolls, the trapezoid mark line (2) forms corresponding pixel serial numbers at the two opposite edges b and a on the CCD photosensitive system (12).
  3. 3. The trapezoidal marker line-based magnetic suspension model roll angle measurement method according to claim 2, wherein the roll angle in S3 The calculation formula of (2) is as follows: 。
  4. 4. The trapezoidal marker line based magnetic suspension model roll angle measurement method according to claim 3, wherein the step S3 further comprises: s4, according to the pixel serial numbers acquired in S2 And pixel number Calculating the average value of the serial numbers of the two pixels in S2 And according to the mean value The axial position of the suspension model (3) in the current measurement state is calculated.
  5. 5. The trapezoidal marker line-based magnetic suspension model roll angle measurement method according to claim 4, wherein the calculation formula of the axial position of the current measurement state in S4 is: ; Wherein, the Representing the axial position of the suspension model (3) in the current measurement state, And (5) representing a calibrated mapping function from the pixel serial number to the actual space coordinate position.
  6. 6. A trapezoidal marker line based magnetic suspension model roll angle measurement system configured to or performing the magnetic suspension model roll angle measurement method of any one of claims 1 to 5, comprising: At least one set of pose measuring sensor (1) comprises an imaging system (11) and a CCD photosensitive system (12) which are electrically connected with each other; a trapezoidal marker line (2) configured to surround a closed annular marker line affixed at a centroid position of the suspension model (3); Wherein the trapezoid marking line (2) is configured such that the geometric width value of the trapezoid marking line (2) in a direction parallel to the axis of the suspension model (3) is monotonically and continuously linearly changed when the length of the trapezoid marking line is Zhou Xiangbian along the suspension model (3), thereby enabling the trapezoid marking line (2) to be in a trapezoid annular structure with unequal-length bottom edges on a cylindrical surface unfolding geometric figure.
  7. 7. The trapezoidal marker line-based magnetic suspension model roll angle measurement system according to claim 6, wherein the pose measurement sensor (1) is used for acquiring an image containing the trapezoidal marker line (2) and identifying pixel serial numbers corresponding to two edge ends of a and b opposite to each other along the axial direction of the suspension model (3) imaged by the trapezoidal marker line (2) on the CCD photosensitive system (12).
  8. 8. The trapezoidal marker line based magnetic suspension model roll angle measurement system according to claim 6, wherein the CCD photosensitive system (12) determines the pixel number at the a-edge by detecting the falling edge of the image signal corresponding to the a-edge of the trapezoidal marker line (2) and determines the pixel number at the b-edge by detecting the rising edge of the image corresponding to the b-edge of the trapezoidal marker line (2).

Description

Method and system for measuring rolling angle of magnetic suspension model based on trapezoidal marker line Technical Field The invention relates to the technical field of magnetic suspension balance systems, in particular to a method and a system for measuring a rolling angle of a magnetic suspension model based on trapezoidal mark lines. Background Currently, in the process of carrying out unsupported suspension on a suspension model by utilizing a magnetic suspension balance system in a wind tunnel test, a pose measurement system based on multi-linear array CCD H-shaped arrangement is often adopted, as shown in figure 1. In the process, generally, a strip-shaped mark line and a ring-shaped mark line which have obvious symmetry with the color difference of the surface of the suspension model are designed and stuck on the surface of the suspension model, and are used for detecting and resolving pose information of the suspension model. The existing suspension model adopts a black strip shape and an annular mark line. The strip-shaped mark lines are respectively imaged on two vertically arranged CCDs (CCD 1 and CCD2 in fig. 1), then the CCD detects the image edges of the mark lines to obtain pixel point serial numbers, and position information of the suspension model in space can be measured through pose resolving. The symmetrical annular mark line is mainly imaged on a CCD (CCD 3 in fig. 1) which is transversely arranged in the middle, then the CCD detects the image edge of the mark line to obtain a pixel point serial number, and the axial position information of the suspension model in space can be measured through pose calculation. However, the scheme for measuring the pose of the suspension model in space, which is commonly used, can only measure the pose of the suspension model with 5 degrees of freedom, and cannot measure the roll angle. Moreover, once the suspension model rolls, if this roll angle is not measured to compensate for the detection of lateral and vertical positions, the pose measurement accuracy of 5 degrees of freedom of the suspension model will be affected. Disclosure of Invention The invention provides a trapezoid mark line-based magnetic suspension model roll angle measurement method and a trapezoid mark line-based magnetic suspension model roll angle measurement system, which are used for solving the technical problems mentioned in the background art. In order to achieve the above purpose, the technical scheme of the invention is realized as follows: The invention provides a trapezoid mark line-based magnetic suspension model roll angle measurement method, which comprises the following steps: S1, firstly setting the rolling angle of the suspension model to be 0 degree in an initial state, acquiring pixel serial numbers corresponding to two opposite edges of an a side and a b side, which are opposite in the axial direction of the suspension model and imaged by a trapezoid mark line on a CCD photosensitive system in the initial state, and recording the difference value of the pixel serial numbers of the two pixel serial numbers ; S2, after the suspension model rolls, in the current measurement state, acquiring pixel serial numbers corresponding to the opposite edge ends a and b of the trapezoidal mark line imaged on the CCD photosensitive system along the axial direction of the suspension model in the current state, and recording the difference value of the pixel serial numbers of the two pixel serial numbers in S2; S3, according to the pixel serial number difference value、Calculating to obtain the roll angle of the suspension model in the current measurement state。 Further, the pixel sequence number difference value in S1The formula of (2) is as follows: ; Wherein, the 、When the two ends are respectively in an initial state, the two opposite edges b and a of the trapezoidal mark line imaged on the CCD photosensitive system correspond to pixel serial numbers; The pixel serial number difference value in the S2 The formula of (2) is as follows: ; Wherein, the 、And after the suspension model rolls, the trapezoid mark lines are provided with pixel serial numbers corresponding to two opposite edges b and a imaged on the CCD photosensitive system. Further, the roll angle in S3The calculation formula of (2) is as follows: 。 Further, the step S3 further includes: s4, according to the pixel serial numbers acquired in S2 And pixel numberCalculating the average value of the serial numbers of the two pixels in S2And according to the mean valueThe axial position of the suspension model in the current measurement state is calculated. Further, the calculation formula of the axial position of the current measurement state in S4 is: ; Wherein, the Representing the axial position of the suspension model in the current measurement state,And (5) representing a calibrated mapping function from the pixel serial number to the actual space coordinate position. The second aspect of the present invention a