A multi-axis actuator detection system

Abstract

A multi-axis actuator detection system relates to a multi-axis actuator detection system of a camera module and a motor, solves the technical defects that the existing multi-axis actuator detection system cannot support the detection of the rolling axis direction and the rolling angle, the detection cost is high, and the measurement precision is low, and contains an electronic calculator, a drive board, a target pattern and a camera; The drive board is connected with the multi-axis actuator, the target pattern is connected with the movable structure of the multi-axis actuator, and the electronic calculator is connected with the drive board and the camera respectively; The camera collects and records the target pattern movement change image signal and sends it to the electronic calculator, the electronic calculator calculates the actual multi-axis movement amount of the multi-axis actuator according to the target pattern movement change image signal, compares it with the standard movement amount corresponding to the output drive control signal, and judges whether the multi-axis actuator is qualified. It can support multi-axis movement amount detection including rolling direction, can accurately measure the movement amount of the rolling shaft, and only needs one camera, the equipment cost is low, and the volume is small.

Description

Technical Field

[0001] This invention relates to a multi-axis actuator detection system for camera modules and motors, wherein the motors include multi-axis voice coil motors, multi-axis memory metal motors, and multi-axis piezoelectric motors. Background Technology

[0002] In recent years, small mobile devices with shooting capabilities have become increasingly popular, and their applications continue to expand, including smartphones, smart glasses, action cameras, law enforcement recorders, and dashcams. These devices typically include at least one compact camera module with zoom, auto-focus, or fixed-focus capabilities. Therefore, the market for such modules is substantial, and its growth is steadily increasing.

[0003] Some camera modules require at least one multi-axis actuator to perform various functions, such as multi-axis image stabilization. Since the quality of the multi-axis actuator affects the overall performance, a reliable inspection system is needed to identify defective units and ensure a high yield rate. Currently, two main types of inspection systems are used:

[0004] The first type of detection system uses laser measurement methods (e.g., US20120105833A1, KR19980086188A) to detect the multi-axis motion of actuators, offering high measurement accuracy and reliability. However, laser measurement methods have difficulty supporting the roll direction, making it impossible to detect the roll angle with a single measuring device. Furthermore, laser measurement methods require multiple laser measuring devices to support multi-axis detection, leading to increased equipment costs.

[0005] The second type of detection system uses camera measurement methods (e.g., JPH1144522A, JP2011237379A, CN102829953B, CN 110300252B) to detect the multi-axis motion of the actuator. It typically requires only one camera, and its equipment cost is usually low. However, it also cannot support the roll axis direction (e.g., CN102829953B), or the measurement accuracy of the roll axis is low. Summary of the Invention

[0006] In summary, the purpose of this invention is to address the shortcomings of existing multi-axis actuator detection systems, such as the inability to support the detection of roll angle in the roll axis direction, high detection cost, and low measurement accuracy, and to propose a multi-axis actuator detection system.

[0007] To solve the technical problem proposed in this invention, the technical solution adopted is as follows:

[0008] A multi-axis actuator detection system is characterized in that the system comprises: an electronic calculator, a drive board, a target pattern, and a camera; the drive board is connected to the multi-axis actuator, the target pattern is connected to the movable structure of the multi-axis actuator, and the electronic calculator is connected to both the drive board and the camera; the electronic calculator changes the drive signal of the multi-axis actuator through the drive board, and the multi-axis actuator performs multi-axis motion on the target pattern according to the drive signal; the camera acquires and records the motion change image signal of the target pattern and sends it to the electronic calculator, which calculates the actual multi-axis motion of the multi-axis actuator based on the motion change image signal of the target pattern, compares it with the standard motion corresponding to the output drive control signal, and determines whether the multi-axis actuator is qualified.

[0009] The multi-axis actuator has three degrees of freedom in the Rx, Ry, and Rz directions. The equations used to calculate the rotation angles βx and βy in the Rx and Ry directions are as follows:

[0010]

[0011]

[0012] Where Δx represents the displacement of the target pattern in the Rx direction, Δy represents the displacement of the target pattern in the Ry direction, and d represents the distance from the surface of the target pattern to the rotation axis of the multi-axis actuator.

[0013] The multi-axis actuator also has a degree of freedom of motion in the Rz direction. The multi-axis actuator detection system can calculate the rotation angle βz in the Rz direction by measuring the rotation of the target pattern in the Rz direction.

[0014] The target pattern comprises a rectangle, and a portion of the rectangle extends beyond one edge of the image reading area of ​​the camera.

[0015] The target pattern comprises four rectangles, with portions of each rectangle extending beyond the four edges of the camera's image reading area.

[0016] The target pattern includes a circular center point located at the center of the camera's image reading area, and two rectangles located on the left and right sides of the circular center point. Parts of the two rectangles extend beyond the left and right edges of the camera's image reading area. The width of the camera's image reading area is greater than its height.

[0017] The target pattern is a two-dimensional pattern in two colors.

[0018] The target pattern is a three-dimensional pattern, comprising a center point, two rectangles, a slope, and three colors; the slope connects one edge of each rectangle; the top of the two rectangles and the center point is marked with color one; the slope is marked with color two; all other faces are marked with color three; the angle between the slope and the z-axis of the multi-axis actuator is between 0 degrees and 45 degrees; based on the change in the area of ​​the slope, the rotation angle βx in the Rx direction of the multi-axis actuator is calculated, and the equation is as follows:

[0019]

[0020] A11 is the area of ​​inclined plane 11 in the image when βx = 0°, and ΔA11 is the change in area of ​​inclined plane 11 in the image after rotation.

[0021] The target pattern is a three-dimensional pattern comprising four rectangles, eight inclined planes, and a center point. The four rectangles extend from the four edges of the camera's image reading area, with each rectangle's two edges connecting to two inclined planes. The distance between the center point and the center of the camera's image reading area is less than 30% of the width and 30% of the height of the image reading area. Based on the area changes of the eight inclined planes, the electronic calculator calculates the rotation angles βx and βy of the multi-axis actuator in the Rx and Ry directions, respectively, using the following equations:

[0022]

[0023]

[0024] A11 and A12 are the areas of the two inclined planes connected to the two edges of the right rectangle in the camera image when βx = 0° and βy = 0°, respectively. A21 and A22 are the areas of the two inclined planes connected to the two edges of the left rectangle in the camera image when βx = 0° and βy = 0°, respectively. ΔA11, ΔA12, ΔA21 and ΔA22 are the changes in the areas of the four inclined planes connected to the four edges of the right and left rectangles in the camera image after the multi-axis actuator performs multi-axis motion on the target pattern according to the drive signal. The electronic calculator calculates the displacement of the center point in the x and y directions based on the position change of the center point. The rotation angle βz of the multi-axis actuator in the Rz direction is calculated based on the rotation of the four rectangles' roll axes.

[0025] The beneficial effects of the present invention are as follows: The multi-axis actuator detection system of the present invention can support the detection of multi-axis motion including the tumbling direction, can accurately measure the motion of the tumbling axis, and only requires one camera, with low equipment cost and small size. Attached Figure Description

[0026] Figure 1 This is a structural diagram of the multi-axis actuator detection system of the present invention;

[0027] Figure 2 This is a block diagram illustrating the structural principle of the multi-axis actuator detection system of the present invention.

[0028] Figure 3 This is a flowchart of the detection process of the multi-axis actuator detection system of the present invention;

[0029] Figure 4 This is a structural diagram of the target pattern of the present invention when it includes a rectangle;

[0030] Figure 5 This is a structural diagram of the target pattern of the present invention when it comprises four rectangles;

[0031] Figure 6 A structural diagram of the target pattern of the present invention comprising a circular center point and two rectangles;

[0032] Figure 7 This is a structural diagram of a three-dimensional pattern comprising a center point, two rectangles, a slope, and three colors, representing the target pattern of the present invention.

[0033] Figure 8 for Figure 7 Front view of the structure;

[0034] Figure 9 This is a structural diagram of the target pattern of the present invention when it is a three-dimensional pattern comprising four rectangles, eight inclined planes and a center point;

[0035] Figure 10 for Figure 9 Front view of the structure;

[0036] Figure 11 for Figure 6 The structural diagram of the target pattern after changing the drive signal of the multi-axis actuator. Detailed Implementation

[0037] The present invention will be further described below with reference to the accompanying drawings and preferred embodiments.

[0038] Reference Figures 1 to 3As shown, the multi-axis actuator detection system disclosed in this invention is mainly used to detect the multi-axis motion of a multi-axis actuator, compare it with a standard motion, and determine whether the multi-axis actuator is qualified. Specifically, it includes: an electronic calculator 1, a drive board 2, a target pattern 3, and a camera 4; the multi-axis actuator 5 to be tested is mounted and fixed on the drive board 2; the electronic calculator 1 is connected to the multi-axis actuator 5 via the drive board 2; the target pattern 3 is connected to the movable structure of the multi-axis actuator 5; the rotating shaft 51 of the multi-axis actuator 5 is vertically fixed; the electronic calculator 1 is also connected to the camera 4 to receive images acquired by the camera 4.

[0039] The detection process for the multi-axis actuator 5 in this invention is as follows:

[0040] 1. The electronic calculator 1 changes the drive signal of the multi-axis actuator 5 through the drive board 2;

[0041] 2. The multi-axis actuator 5 drives the target pattern 3 to perform multi-axis motion according to the driving signal;

[0042] 3. The camera 4 acquires and records image signals of the motion changes of the target pattern 3, and sends them to the electronic calculator 1;

[0043] 4. Repeat steps 1 to 3 until the predetermined multi-axis motion of the electronic calculator 1 is completed;

[0044] 5. The electronic calculator 1 analyzes the image signal output by the camera 4 and calculates the amount of multi-axis motion of the multi-axis actuator 5;

[0045] 6. The electronic calculator 1 calculates the actual multi-axis motion of the multi-axis actuator based on the image signal of the motion change of the target pattern 3, and compares it with the standard motion corresponding to the output drive control signal to determine whether the multi-axis actuator 5 is qualified.

[0046] like Figure 11 As shown, existing multi-axis actuators typically have three degrees of freedom: Rx, Ry, and Rz. The equations used to calculate the rotation angles βx and βy in the Rx and Ry directions are as follows:

[0047]

[0048]

[0049] Where Δx represents the displacement of the target pattern in the Rx direction, and Δy represents the displacement of the target pattern in the Ry direction. The multi-axis actuator detection system can calculate the rotation angle βz in the Rz direction by measuring the rotation of the target pattern in the Rz direction.

[0050] In specific implementation, the target pattern can be constructed in various ways. The following five examples of construction methods are used to further illustrate the present invention.

[0051] Example 1

[0052] Reference Figure 4 As shown, the target pattern includes a rectangle, and a portion of the rectangle extends beyond the left edge of the camera's image reading area.

[0053] Example 2

[0054] Reference Figure 5 As shown, the target pattern comprises four rectangles, with the portions of the four rectangles extending beyond the four edges of the image reading area of ​​the camera.

[0055] Example 3

[0056] Reference Figure 6 As shown, the target pattern includes a circular center point located at the center of the camera's image reading area, and two rectangles located on the left and right sides of the circular center point. Parts of the two rectangles extend beyond the left and right edges of the camera's image reading area; the width of the camera's image reading area is greater than its height.

[0057] In the above three embodiments, the width of the image reading area is greater than its height; in embodiment three, the distance between the center of the circular center point and the center of the image reading area is less than 30% of the image width and 30% of the height.

[0058] Preferably, the target patterns in embodiments one to three of the present invention are all two-dimensional patterns and have only two colors, such as black and white. Therefore, the detection systems in embodiments one to three of the present invention can support and employ grayscale cameras, which can increase the signal-to-noise ratio of the camera and the accuracy of detection.

[0059] Since the patterns in embodiments one to three of the present invention include rectangles that extend beyond the edges, the position close to the edge of the image can be effectively utilized to improve the detection accuracy in the roll axis direction.

[0060] Since the pattern in Embodiment 3 of the present invention includes a circular center point at the junction center, and the resolution and distortion ratio of the camera lens center are ideal on all four sides, the detection system of the present invention can improve the detection accuracy when it judges the displacement of the pattern in the x and y directions by observing the movement of the circular center point.

[0061] Example 4

[0062] Reference Figure 7 and Figure 8As shown, the target pattern is a three-dimensional pattern, comprising a center point 30, two rectangles, a ramp 11, and three colors; the two rectangles are rectangle one 31 and rectangle two 32, and the ramp 11 connects one edge of rectangle one 31; color one is located at the top of the two rectangles and the center point 30; color two is located on the ramp 11; and color three is located on all other surfaces; color one, color two, and color three are three different colors; the angle between the ramp 11 and the z-axis of the multi-axis actuator is between 0 degrees and 45 degrees; based on the change in the area of ​​the ramp 11, the electronic calculator calculates the rotation angle βx in the Rx direction of the multi-axis actuator, and the equation is as follows:

[0063]

[0064] A11 is the area of ​​inclined plane 11 in the image when βx = 0°, and ΔA11 is the change in area of ​​inclined plane 11 in the image after rotation.

[0065] Example 5

[0066] Reference Figure 9 and Figure 10 As shown, the target pattern is a three-dimensional pattern comprising four rectangles, eight inclined planes, and a center point. The four rectangles are rectangle 1 (31), rectangle 2 (32), rectangle 3 (33), and rectangle 4 (34). The eight inclined planes are marked 11, 12, 21, 22, 33, 34, 43, and 44. Each rectangle extends from one of the four edges of the camera's image reading area, with each rectangle's two edges connecting to two inclined planes. The distance between the center point 30 and the center of the camera's image reading area is less than 30% of the width and 30% of the height of the camera's image reading area. Based on the area changes of the eight inclined planes, the electronic calculator calculates the rotation angle βx in the Rx direction and the rotation angle βy in the Ry direction of the multi-axis actuator, using the following equations:

[0067]

[0068]

[0069] A11 and A12 are the areas of the two inclined planes connected to the two edges of the right rectangle in the camera-captured image when βx = 0° and βy = 0°, respectively. A21 and A22 are the areas of the two inclined planes connected to the two edges of the left rectangle in the camera-captured image when βx = 0° and βy = 0°, respectively. ΔA11, ΔA12, ΔA21, and ΔA22 are the changes in the areas of the four inclined planes connected to the four edges of the right and left rectangles in the camera-captured image after the multi-axis actuator performs multi-axis motion on the target pattern according to the drive signal. The electronic calculator calculates the displacement of the center point in the x and y directions based on the change in the center point's position. The rotation angle βz of the multi-axis actuator in the Rz direction is calculated based on the rotation of the four rectangles' roll axes. Therefore, the detection system in Embodiment 5 of the present invention can support independent detection of the five-axis motion (x, y, Rx, Ry, and Rz) of the actuator. Preferably, Embodiment 5 of the present invention uses a target pattern with more than three colors and a color camera, which makes it easier to identify different inclined planes. In other embodiments, the actuator may be a voice coil motor, a stepper motor, a memory metal motor, or a piezoelectric motor; the detection device may not include a drive board; the detection device may adjust and optimize control parameters according to the detection data, and store the control parameters in memory to achieve a correction effect; the center point may be a shape other than a circle, such as a square; different numbers of rectangles and center points in the target pattern are also within the protection scope of this invention.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-axis actuator detection system, characterized in that... The system includes: an electronic calculator, a driver board, a target pattern, and a camera; The drive board is connected to the multi-axis actuator, the target pattern is connected to the movable structure of the multi-axis actuator, and the electronic calculator is connected to the drive board and the camera respectively. The electronic calculator changes the drive signal of the multi-axis actuator through the drive board. The multi-axis actuator performs multi-axis motion on the target pattern according to the drive signal. The camera collects and records the image signal of the target pattern's motion change and sends it to the electronic calculator. The electronic calculator calculates the actual multi-axis motion of the multi-axis actuator based on the image signal of the target pattern's motion change and compares it with the standard motion corresponding to the output drive control signal to determine whether the multi-axis actuator is qualified. The target pattern is a three-dimensional pattern, comprising a center point, two rectangles, a ramp, and three colors; the ramp connects one edge of each rectangle; the top of the two rectangles and the center point is marked with color one; the ramp is marked with color two; all other faces are marked with color three; the angle between the ramp and the z-axis of the multi-axis actuator is between 0 degrees and 45 degrees; the rotation angle of the multi-axis actuator in the Rx direction is calculated based on the change in the area of ​​the ramp. Its equation is as follows: ， yes The area of ​​inclined plane 11 in the image, It represents the change in area of ​​inclined plane 11 in the image after rotation.

2. The multi-axis actuator detection system according to claim 1, characterized in that: The target pattern is a three-dimensional pattern comprising four rectangles, eight inclined planes, and a center point. The four rectangles extend from the four edges of the camera's image reading area, with each rectangle's two edges connecting to two inclined planes. The distance between the center point and the center of the camera's image reading area is less than 30% of the width and 30% of the height of the image reading area. Based on the area variations of the eight inclined planes, the electronic calculator calculates the rotation angle of the multi-axis actuator in the Rx direction. and the rotation angle in the Ry direction Its equation is as follows: ， ， They are and The area of ​​the two inclined planes connecting the two edges of the rectangle on the right in the image captured by the camera. They are and The area of ​​the two sloping surfaces connecting the two edges of the left rectangle in the image captured by the camera. These are: the area changes of the four inclined planes connecting the four edges of the right and left rectangles in the camera-captured image after the multi-axis actuator performs multi-axis motion on the target pattern according to the drive signal; the electronic calculator calculates the displacement of the center point in the x and y directions based on the position change of the center point; and the rotation angle of the multi-axis actuator in the Rz direction is calculated based on the rotation of the four rectangles' roll axes.

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