Center shaft inclination angle adjusting device and method for photoelectric precision target test system

Abstract

The invention provides a central shaft inclination angle adjusting device and method for a photoelectric precision target testing system, and belongs to the technical field of density testing. The center shaft inclination angle adjusting device forms a stable and flexible mechanical supporting system through a plurality of sets of adjusting supporting assemblies capable of cooperating and differentially stretching out and drawing back, and pitching adjustment and roll deviation correction of the bearing platform can be achieved. And an orientation feedback unit and a calculation driving unit are integrated, so that an intelligent closed-loop adjustment function is formed, and high-precision adjustment is ensured. The method for adjusting the inclination angle of the central shaft realizes an intelligent control process with deep cooperation of software and hardware, a physical posture is leveled on the hardware by adjusting a supporting assembly, and coordinate transformation parameters for converting a measured value of a photoelectric precision test target system from a supporting plate coordinate system to a geodetic horizontal coordinate system are synchronously generated on the software. Automatic correction of system errors is achieved, synchronous double correction is achieved through software and hardware, and the testing precision of the photoelectric precision target testing system is improved.

Description

Technical Field

[0001] This invention belongs to the field of density testing technology, specifically relating to a central axis tilt angle adjustment device for a photoelectric precision target testing system, and a central axis tilt angle adjustment method for a photoelectric precision target testing system. Background Technology

[0002] Density is a key factor in measuring equipment performance and determining its actual effectiveness, and it is also one of its important technical indicators. Therefore, accurate density testing helps to more accurately grasp the actual performance of the equipment, thereby reasonably assessing its ability to act on targets in application scenarios. CCD convergent photoelectric density testing systems have become the mainstream measurement equipment in this field due to their significant advantages such as high automation, excellent measurement accuracy, and adaptability to high-frequency continuous trigger testing.

[0003] A 2025 research paper published by the Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) of the Chinese Academy of Sciences, entitled "Correction of Static Pointing Error of a Novel Optical Testing Target," investigated the static pointing error of a novel optical testing target. Its core findings directly reflect the shortcomings of existing systems:

[0004] (1) Fixed structure leads to excessive pointing error: The field of view center axis of the existing optical test target adopts a fixed angle design and no tilt adjustment mechanism is set. In actual testing, due to terrain undulations, station position deviations and other reasons, the system exhibits significant spatial static pointing error, which directly causes the target center to deviate from the preset measurement area.

[0005] (2) No hardware adjustment means, only software correction: Although the study compensates for pointing error with software by fitting the error model with the least squares method, it does not propose any hardware tilt adjustment scheme. However, if the on-site station placement deviation is too large (such as the terrain conditions causing the target center to deviate significantly from the field of view), software correction alone cannot completely make up for the error. Summary of the Invention

[0006] The purpose of this invention is to solve the problem that the central axis of existing optical test targets is fixed and there is no hardware adjustment means, relying only on software correction. Instead, it provides a technical means that combines hardware and software to horizontally adjust the central axis of the field of view of the photoelectric precision target test system. This allows for flexible adjustment of the attitude of the central axis of the test system's field of view without affecting the original measurement accuracy or increasing the difficulty of use, thus adapting to the deployment requirements of complex test sites.

[0007] To achieve the above objectives, the technical solution provided by this invention is:

[0008] A device for adjusting the center axis tilt angle of a photoelectric precision target testing system is provided, including a support platform, an adjustment support assembly, an orientation feedback unit, and a calculation drive unit. The support platform supports the photoelectric precision test target system and includes a tray with multiple positioning interfaces that match the bottom protrusions of the photoelectric precision test target system. Multiple sets of adjustment support assemblies are evenly arranged along the circumference of the tray. Each set of adjustment support assemblies includes a telescopic push rod and a base. The upper end of the telescopic push rod is hinged to the tray via a first hinge, which restricts the rotational freedom of the telescopic push rod about its own axis. The lower end of the telescopic push rod is hinged to the base via a second hinge. The base is used to fix the device to the ground, and the telescopic push rod is used to adjust the target length of the adjustment support assembly so that the tray is aligned with the target axis. The target tilt angle is adjusted accordingly. An azimuth feedback unit, fixed to the bottom of the support plate, monitors the pitch and roll angles of the support plate relative to the ground horizontal plane. A calculation drive unit is electrically connected to both the azimuth feedback unit and the adjustment support assembly, receiving pitch and roll angle data monitored by the azimuth feedback unit and controlling the extension and retraction of the adjustment support assembly. Based on the set target tilt angle of the support plate and the pitch and roll angles monitored by the azimuth feedback unit, the calculation drive unit calculates the target length of each set of adjustment support assemblies. Based on the pitch and roll angles and the length data of each adjustment support assembly, coordinate transformation parameters are constructed to convert the measured values ​​of the photoelectric precision testing target system from the support plate coordinate system to the geodetic horizontal coordinate system, thereby achieving automatic correction of system errors.

[0009] Furthermore, the adjustment support components are provided in three sets, which are distributed on the three vertices of an isosceles triangle with the geometric center of the pallet as the center of symmetry.

[0010] Furthermore, the telescopic push rod includes an electric push rod and a support rod; the adjustment support assembly also includes a placement platform set parallel to the support plate; the upper end of the electric push rod is hinged to the support plate and the lower end is welded to the top surface of the placement platform; the upper end of the support rod is welded to the bottom surface of the placement platform and the lower end is hinged to the base; the calculation drive unit is fixed on the placement platform.

[0011] Furthermore, the first hinge is a Hooke hinge, and the second hinge is a ball joint; the upper end of the electric push rod is hinged to the support plate via a Hooke hinge, and the lower end of the support rod is hinged to the base via a ball joint.

[0012] Furthermore, the calculation and driving unit integrates a sensor communication interface, a PWM motor drive circuit, a locking trigger logic circuit, and an embedded calculation processor. The sensor communication interface is used to read the extension amount of the electric actuator in real time, the PWM motor drive circuit is used to drive the electric actuator, the locking trigger logic circuit is used to lock the electric actuator, and the embedded calculation processor is connected to the sensor communication interface, the PWM motor drive circuit, and the locking trigger logic circuit respectively. It is used to receive the signals transmitted by the sensor communication interface, calculate the target length and correction parameters of each set of adjustment support components, and send control signals to the PWM motor drive circuit and the locking trigger logic circuit.

[0013] Furthermore, the orientation feedback unit includes a signal conditioning circuit and a sensor measurement component. The sensor measurement component is electrically connected to the signal conditioning circuit and is used to acquire the pitch and roll angles of the pallet in real time. The signal conditioning circuit integrates a filtering algorithm to eliminate interference and smooth the data.

[0014] A method for adjusting the tilt angle of the central axis of a photoelectric precision target testing system is also provided, which uses the aforementioned central axis tilt angle adjustment device to adjust the tilt angle, and includes the following steps:

[0015] Step 1, Device setup and system installation: Fix the adjustment support components to the predetermined position at the test site using the base, and then place the photoelectric precision target test system on the support platform;

[0016] Step 2, Target Attitude Calculation: Based on the on-site terrain and testing requirements, determine the target tilt angle and input it into the calculation drive unit. The calculation drive unit uses a spatial geometry algorithm to calculate the target length of each adjustment support component based on the geometric coordinate position of each telescopic push rod at the bottom of the support plate.

[0017] Step 3, Differential Drive: The calculation drive unit adjusts the extension and retraction of each telescopic push rod based on the target length of each adjustment support component, so that the adjustment support component can smoothly reach the target posture.

[0018] Step 4: Constructing a coordinate transformation model and error compensation: Based on the pitch angle, roll angle, and current length data of each adjustment support component monitored in real time by the azimuth feedback unit, the solution driving unit establishes a spatial coordinate transformation model from a local coordinate system based on the current plane of the support plate to a global coordinate system based on the horizontal plane of the earth. Based on this, spatial coordinate transformation parameters are generated to correct the measurement values ​​of the photoelectric precision target testing system, so as to realize the automatic correction of system errors.

[0019] Furthermore, in step 4, the construction of the spatial coordinate transformation model includes:

[0020] Step 4-1: Define the coordinate system: Define the geodetic horizontal datum as the global coordinate system. The current plane of the pallet is a local coordinate system. ;

[0021] Step 4-2: Constructing the rotation matrix: Based on the pitch and roll angle data measured in real time by the receiving azimuth feedback unit, the solution drive unit constructs a local coordinate system. Convert coordinates in the local coordinate system to the global coordinate system The required rotation matrix containing pitch and roll angle information ;

[0022] Step 4-3: Construct the translation vector: Based on the length data of each adjustment support component, calculate the translation vector in the local coordinate system. Geometric center and global coordinates of the photoelectric precision target testing system based on the standard The vertical displacement vector below ;

[0023] Step 4-4: Establish coordinate transformation relationship: based on rotation matrix and vertical displacement vector Constructing from a local coordinate system To the global coordinate system The complete spatial transformation relationship is expressed as: ,in Indicates the photoelectric precision test target system in the global coordinate system The corrected attitude and altitude deviation measurements are as follows. This indicates the photoelectric precision testing target system in the local coordinate system. The output is the original measurement value.

[0024] Furthermore, in step 3, during the extension and retraction of the telescopic push rod, the calculation drive unit detects the actual length of each adjustment support component in real time, and compares the actual length with the target length in real time and performs PID adjustment to ensure that the adjustment support component reaches the target posture.

[0025] The advantages of this invention are:

[0026] 1. This invention provides a center axis tilt angle adjustment device for a photoelectric precision target testing system. Through multiple sets of adjustable support components that can coordinate differentially extend and retract, a stable and flexible mechanical support system is formed, enabling pitch adjustment and roll deviation correction of the carrying platform within ±12°. The device integrates an azimuth feedback unit and a calculation drive unit. Based on the acquired tilt angle of the carrying platform, it calculates the target length of the adjustable support components to adjust the tilt angle of the carrying platform, forming an intelligent closed-loop adjustment function that ensures high-precision adjustment. Furthermore, it can quickly construct an ideal measurement benchmark in complex environments without relying on a flat ground, greatly expanding the deployment range and applicable scenarios of the photoelectric precision target testing system.

[0027] 2. This invention provides a method for adjusting the center axis tilt angle of a photoelectric precision target testing system. It achieves a deeply integrated intelligent control process combining hardware and software. With accurate calculation as its core, the calculation drive unit can calculate the target length of the adjustment support component based on the target tilt angle and the pitch and roll angles monitored in real time by the azimuth feedback unit. This ensures a clear target for the adjustment process and avoids trial and error. Simultaneously, the hardware adjusts the physical attitude of the support component, while the software synchronously generates coordinate transformation parameters to convert the measured values ​​of the photoelectric precision target system from the support coordinate system to the earth's horizontal coordinate system. This enables automatic correction of system errors. Through synchronous dual correction via hardware and software, the adjustment process is highly automated, and the testing accuracy of the photoelectric precision target testing system is improved. Attached Figure Description

[0028] The features and advantages of the invention will become more readily apparent from the following description with reference to the accompanying drawings, which are not drawn to scale and some features are enlarged or reduced to show details of specific parts.

[0029] Figure 1 This is a schematic diagram of the central axis tilt angle adjustment device of the present invention;

[0030] Figure 2 This is a front view of the central axis tilt angle adjustment device of the present invention;

[0031] Figure 3 This is a top view of the central axis tilt angle adjustment device of the present invention;

[0032] Figure 4 yes Figure 3 AA view.

[0033] In the diagram: 1-base; 2-support plate; 21-positioning interface; 3-calculation drive unit; 4-placement platform; 5-first hinge; 6-adjustment support assembly; 7-second hinge; 8-orientation feedback unit. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and exemplary embodiments thereof. It should be noted that the following detailed description of the present invention is for illustrative purposes only and is not intended to limit the scope of the invention.

[0035] To address the problems of existing CCD convergent photoelectric density testing systems, such as "the fixed angle between the field of view center axis and the horizontal plane leads to low flexibility and the inability to correct target center deviation under station deployment limitations," this invention provides a center axis tilt angle adjustment device for a photoelectric precision target testing system. The device aims to achieve horizontal tilt angle adjustment within ±12° of the test system's field of view center axis through a split-structure design and automated adjustment module, while ensuring that the accuracy of the original measurement system is not affected and that it is easy to use.

[0036] like Figure 1 , 2 As shown in Figures 3 and 4, the central axis tilt angle adjustment device for a photoelectric precision target testing system provided by the present invention includes a bearing platform, an adjustment support assembly 6, an orientation feedback unit 8, and a calculation drive unit 3.

[0037] like Figure 1 As shown, the support platform is used to support the photoelectric precision test target system. The support platform includes a tray 2, which has multiple positioning interfaces 21 that match the bottom protrusions of the photoelectric precision test target system. The support platform, as the main support structure of the adjustment device, is made of high-strength metal material and can stably support the photoelectric precision test target system. The size and shape of the positioning interfaces 21 on the tray 2 are adapted to the original bottom protrusions of the photoelectric precision test target system, preventing mechanical interference during installation and avoiding displacement during system movement and adjustment, thus ensuring that the measurement function of the test system is not affected.

[0038] like Figure 2 , 4 As shown, multiple sets of adjustment support components 6 are evenly arranged around the circumference of the support plate 2. Each set of adjustment support components 6 includes a telescopic push rod and a base 1. The upper end of the telescopic push rod is hinged to the support plate 2 via a first hinge 5. The first hinge 5 restricts the rotational freedom of the telescopic push rod about its own axis. The first hinge 5 allows the telescopic push rod to pitch and tilt relative to the support platform, but strictly restricts its rotational freedom about its own axis. The lower end of the telescopic push rod is hinged to the base 1 via a second hinge 7, which can adapt to multiple angles of ground tilt. The base 1 is used to fix it to the ground, and the telescopic push rod is used to adjust the target length of the adjustment support component 6 so that the support plate 2 tilts according to the target tilt angle.

[0039] The orientation feedback unit 8 is fixed to the bottom surface of the pallet 2 and is used to monitor the pitch angle and roll angle of the pallet 2 relative to the horizontal plane of the ground; and transmits the pitch angle and roll angle data to the calculation drive unit 3 to form a closed-loop control.

[0040] The calculation drive unit 3 is electrically connected to the azimuth feedback unit 8 and the adjustment support assembly 6, respectively. It receives pitch and roll angle data monitored by the azimuth feedback unit 8 and controls the extension / retraction of the adjustment support assembly 6. Based on the set target tilt angle of the support plate 2 and the pitch and roll angles monitored by the azimuth feedback unit 8, the calculation drive unit 3 calculates the target length of each set of adjustment support assemblies 6. Based on the pitch angle, roll angle, and length data of each adjustment support assembly 6, it constructs coordinate transformation parameters to convert the measured values ​​of the photoelectric precision test target system from the support plate 2 coordinate system to the earth's horizontal coordinate system, thereby achieving automatic correction of system errors. Specifically, system errors refer to the systematic measurement errors caused by the inconsistency between the actual attitude of the support plate 2 and the earth's horizontal plane during the data processing of the photoelectric precision test target system. The calculation drive unit 3 is the core control and calculation center of this invention. Its main responsibility is to establish a mathematical mapping relationship between the "target tilt angle" and the "extension / retraction of each set of adjustment support assemblies 6," achieving precise control of the adjustment device's attitude. This unit works collaboratively through two core processes: hardware motion control and software data correction.

[0041] This invention provides a center axis tilt adjustment device for a photoelectric precision target testing system. Through groups of adjustable support components 6 that can coordinate and differentially extend and retract, a stable and flexible mechanical support system is formed, enabling pitch adjustment and roll deviation correction of the supporting platform within ±12°. It also integrates an azimuth feedback unit 8 and a calculation drive unit, forming an intelligent closed-loop adjustment function to ensure high-precision adjustment. Furthermore, it can quickly construct an ideal measurement benchmark in complex environments without relying on flat ground, greatly expanding the deployment range and applicable scenarios of the photoelectric precision target testing system.

[0042] In this embodiment, the adjustment support assembly 6 is provided in three sets, which are distributed on the three vertices of an isosceles triangle with the geometric center of the support plate 2 as the center of symmetry. This isosceles triangular symmetrical three-point support design utilizes the geometric characteristics of a triangle to achieve force balance and strong stability, resulting in efficient and precise leveling, adaptability to various load conditions, simple and compact structure, reduced assembly and maintenance costs, and ensuring high-precision and high-reliability operation of the adjustment device.

[0043] like Figure 2 , 4 As shown, the telescopic push rod includes an electric push rod and a support rod; the adjustment support assembly 6 also includes a placement platform 4 set parallel to the support plate 2; the upper end of the electric push rod is hinged to the support plate 2 and the lower end is welded to the top surface of the placement platform 4; the upper end of the support rod is welded to the bottom surface of the placement platform 4 and the lower end is hinged to the base 1; the calculation drive unit 3 is fixed on the placement platform 4.

[0044] In this embodiment, the electric actuator includes a motor, a precision lead screw, and a telescopic sleeve. The motor is a high-torque servo motor. The output end of the servo motor is connected to the precision lead screw, which drives the telescopic sleeve to extend and retract via lead screw transmission. This allows the three adjusting support components 6 to extend to different lengths, achieving large-stroke differential adjustment of the tilt angle of the bearing platform. In other embodiments, other components capable of telescopic functionality may also be used.

[0045] Meanwhile, a guide anti-rotation mechanism is used between the telescopic sleeve and the precision lead screw to prevent the telescopic sleeve from rotating circumferentially when subjected to torque. Specifically, the guide anti-rotation mechanism employs a trapezoidal thread self-locking system, relying on the lead angle of the trapezoidal thread of the lead screw to achieve anti-slip after power failure, ensuring that the position does not slip after power is cut off. In other embodiments, the shape of the telescopic sleeve can also be set to square to prevent the telescopic push rod from rotating circumferentially when subjected to torque.

[0046] In this embodiment, the first hinge 5 is a Hooke hinge, and the upper end of the electric push rod is hinged to the support plate 2 via a Hooke hinge. In order to prevent the bearing platform from undergoing unexpected horizontal torsion around the vertical axis, at least one of the three sets of adjustment support components 6 is a Hooke hinge structure, or all of them can be Hooke hinges. The second hinge 7 is a ball joint, and the lower end of the support rod is hinged to the base 1 via a ball joint. The lower end of the support rod can be adapted to the base 1 at multiple angles via the ball joint. When the bearing platform tilts significantly, causing a slight change in the angle of the telescopic push rod, the bottom surface of the base 1 can always adaptively conform to the ground, ensuring the stability of the adjustment device.

[0047] The orientation feedback unit 8 includes a signal conditioning circuit and a sensor measurement component. The sensor measurement component is electrically connected to the signal conditioning circuit and is fixed to the geometric center of the bottom surface of the support plate 2. It is used to acquire the pitch and roll angles of the support plate in real time. The signal conditioning circuit integrates a filtering algorithm to eliminate interference and smooth the data. It is responsible for processing the raw data acquired by the sensor measurement component and ensuring that the data output to the calculation and driving unit 3 is filtered data.

[0048] In this embodiment, the sensor measurement component is a high-precision dual-axis electronic tilt sensor. The dual-axis electronic tilt sensor is located at the geometric center of the bottom surface of the support plate 2. To ensure that the sensor coordinate system remains parallel to the mechanical coordinate system of the support plate 2, thus accurately reflecting the spatial attitude of the carrying platform, the dual-axis electronic tilt sensor has a dual-axis attitude capture function, acquiring in real time the pitch angle (i.e., the rise / dive angle of the field of view center axis) and roll angle (i.e., the left and right tilt angle of the support plate 2) relative to the horizontal gravity plane. Within an adjustment range of ±12°, it captures minute angular changes through internal high-frequency sampling (e.g., 10Hz~20Hz), with a resolution better than 0.01°.

[0049] To address the minor vibrations that may occur during servo motor driving, the signal conditioning circuit integrates a filtering algorithm, preferably a Kalman filter, to eliminate high-frequency noise interference and output a smooth and stable angle value to the solution drive unit 3.

[0050] The orientation feedback unit 8 acts as a bridge connecting "mechanical action" and "data correction," and has the following two advantages:

[0051] Motion control closed loop (preventing twisting and tilting): When the calculation drive unit 3 commands the three telescopic push rods to perform differential telescopic extension and retraction, the orientation feedback unit 8 provides real-time feedback on the current actual attitude. If the pallet 2 experiences unexpected roll (left or right tilt) due to uneven ground or differences in the speed of the telescopic push rods, this unit will immediately transmit the deviation signal to the calculation drive unit 3. The calculation drive unit 3 will then fine-tune the speed of the three servo motors to correct the roll error and ensure that the pallet 2 moves only in the preset pitch direction, achieving precise "pure pitch" adjustment.

[0052] Measurement correction benchmark (providing the basis for calculation): When the adjustment device is locked in attitude for equipment accuracy testing, the orientation feedback unit 8 transmits the final static angle data to the calculation drive unit 3 via RS485 / I2C interface. This data is the sole basis for generating the "rotation matrix" and directly determines the accuracy of subsequent correction of the motion trajectory coordinate error of the projectile.

[0053] The calculation and drive unit 3 integrates a sensor communication interface, a PWM motor drive circuit, a locking trigger logic circuit, and an embedded calculation processor. The sensor communication interface connects to the encoder inside the motor to read the extension amount of the electric push rod in real time. The PWM motor drive circuit receives the weak logic signal from the embedded calculation processor, amplifies it into a high-power pulsating current, and drives the electric push rod to run. The locking trigger logic circuit is used to lock the electric push rod. When the target position is reached or a dangerous situation occurs, it directly outputs a signal to control the electromagnetic brake of the motor to lock. The embedded calculation processor is connected to the sensor communication interface, the PWM motor drive circuit, and the locking trigger logic circuit respectively. It is used to receive the signals transmitted by the sensor communication interface, calculate the target length and correction parameters of each of the three sets of adjustment support components 6, and send control signals to the PWM motor drive circuit and the locking trigger logic circuit to form a closed-loop control.

[0054] The solution driving unit 3 works in concert through two core processes: hardware motion control and software data correction. The following is a detailed explanation of these processes.

[0055] Hardware motion control principle: Given the isosceles triangle structure of the three high-precision adjustment support components 6 used in this invention, the calculation and drive unit 3 no longer uses simple synchronous lifting control, but instead employs a control logic of "spatial inverse kinematics calculation + multi-axis differential drive".

[0056] Inverse spatial kinematics calculation: After the operator inputs the target tilt angle (pitch angle, roll angle), the embedded calculation processor uses spatial geometry algorithms based on the coordinates of the vertices of an isosceles triangle to inversely calculate the target extension lengths (L1, L2, L3) that the three adjustment support components 6 need to achieve. For example, to achieve a 10° upward tilt of the field of view center axis, the processor calculates that the front adjustment support component 6 needs to be shortened, while the two rear adjustment support components 6 need to be extended by a specific value, thereby constructing the target slope.

[0057] Multi-axis cooperative closed-loop control: After calculating the three target extension lengths, the PWM motor drive circuit simultaneously sends pulse signals with different duty cycles to three high-torque servo stepper motors. During the motion, the sensor communication interface reads the actual extension amount of each telescopic push rod in real time. The embedded solution processor compares the "actual length" with the "target length" in real time and performs PID adjustment to ensure that the three telescopic push rods, although having different speeds and strokes, can move in sync and smoothly reach the target posture. The embedded solution processor integrates spatial inverse kinematics algorithms and PID control algorithms.

[0058] Center of gravity verification and safety locking: Before executing the action, the spatial inverse kinematics algorithm and PID control algorithm inside the drive unit 3 will verify the system's center of gravity projection point under the target attitude. If the center of gravity exceeds the stable area formed by the three telescopic push rods (i.e., there is a risk of overturning), the action will be refused and an alarm will be triggered. After the action is completed, the lock trigger logic circuit outputs a signal to activate the self-locking function, ensuring absolute stillness during measurement.

[0059] Software data correction principle: Due to the tilt of the adjustment device, the center axis of the field of view of the CCD convergent photoelectric precision target testing system is spatially deflected, and the original measurement coordinate system no longer coincides with the geodetic coordinate system. The calculation drive unit 3 eliminates system errors through the following steps: The calculation processor synchronously receives two types of data: one is the electronic tilt sensor data (real-time pitch angle and roll angle) collected through the sensor communication interface unit; the other is the real-time extension and retraction height data of the three support components.

[0060] The present invention also provides a method for adjusting the tilt angle of the central axis of a photoelectric precision target testing system, which is used to adjust the tilt angle using the above-mentioned central axis tilt angle adjustment device, and includes the following steps:

[0061] Step 1, Device setup and system installation: Fix the adjustment support assembly 6 to the predetermined position at the test site via the base 1, and then place the photoelectric precision target test system on the support platform;

[0062] Step 2, Target Attitude Calculation: Based on the on-site terrain and test requirements, determine the target tilt angle and input it into the calculation drive unit 3. The calculation drive unit 3 uses a spatial geometry algorithm to calculate the target length of each adjustment support component 6 based on the geometric coordinate position of each telescopic push rod at the bottom of the support plate 2.

[0063] Step 3, Differential Drive: The calculation drive unit 3 adjusts the extension and retraction of each telescopic push rod based on the target length of each adjustment support component 6, so that the adjustment support component 6 can smoothly reach the target posture.

[0064] Step 4: Constructing a coordinate transformation model and error compensation: Based on the pitch angle, roll angle, and current length data of each adjustment support component 6 monitored in real time by the orientation feedback unit 8, the solution driving unit 3 establishes a spatial coordinate transformation model from a local coordinate system based on the current plane of the support plate 2 to a global coordinate system based on the earth's horizontal plane. Based on this, spatial coordinate transformation parameters are generated to correct the measured values ​​of the photoelectric precision target testing system, so as to realize the automatic correction of system errors.

[0065] This invention provides a method for adjusting the center axis tilt angle of a photoelectric precision target testing system. It achieves a deeply integrated intelligent control process combining hardware and software. With accurate calculation as its core, the calculation drive unit can calculate the target length of the adjustment support component 6 based on the target tilt angle and the pitch and roll angles monitored in real time by the azimuth feedback unit 8. This makes the adjustment process targeted and avoids trial and error. Simultaneously, the hardware adjusts the physical attitude of the support component 6, while the software synchronously generates coordinate transformation parameters to convert the measured values ​​of the photoelectric precision target testing system from the coordinate system of the support plate 2 to the geodetic horizontal coordinate system. This enables automatic correction of system errors, resulting in a highly automated adjustment process and improved testing accuracy of the photoelectric precision target testing system.

[0066] The following is a detailed explanation of each step:

[0067] In step 1, the adjustment device is fixed to the ground at the test site via base 1. The three bases 1 automatically and adaptively conform to the ground, placing the CCD convergent photoelectric precision target testing system on the support platform, ensuring that its bottom protrusion and the positioning interface 21 on the support plate 2 are tightly fitted. The positioning interface 21 is used to lock and fix the testing system, ensuring that the center axis of the testing system's field of view is relatively stationary with respect to the coordinate system of the support platform. The tight fit between the bottom protrusion and the positioning interface 21 creates friction to maintain the relative stationary position of the testing system and the support platform. After the bottom protrusion of the testing system is placed into the positioning interface 21, a metal pressure plate can be used to span the bottom protrusion and tightened onto the support platform with bolts, thereby rigidly locking the testing system and preventing it from sliding.

[0068] In step 2, the operator inputs the target tilt angle (e.g., the field of view center axis needs to be raised by 10°, i.e., pitch angle ±10°, roll angle 0°) into the calculation drive unit according to the site terrain or testing requirements. After receiving the command, the calculation drive unit 3 uses a spatial inverse kinematics algorithm based on the geometric coordinate relationship of the three telescopic push rods at the bottom of the support platform to calculate the target telescopic lengths (L1, L2, L3) that the three sets of adjustment support components 6 need to achieve respectively.

[0069] In step 3, the PWM motor drive circuit simultaneously sends drive signals with different duty cycles to the three motors. This controls the extension and retraction of the three telescopic push rods to ensure that the adjustment support assembly 6 reaches the target extension and retraction length. During the movement, the orientation feedback unit 8 monitors the platform's pitch and roll angles in real time. If an unexpected roll deviation is detected (caused by uneven ground or inconsistent motor speeds), the drive unit 3 fine-tunes the speed of each motor in real time to ensure the platform smoothly transitions to the target posture.

[0070] When the orientation feedback unit 8 detects that the current angle matches the target angle, and all three sets of adjustment support components 6 have reached the target length, the lock trigger logic circuit outputs a level signal, activating the locking mechanism within the adjustment support component 6, thus "freezing" the attitude of the adjustment device. The system performs a center of gravity safety check, confirming that the center of gravity projection point under the current attitude is within the range of the bottom support triangle to prevent tipping. The locking mechanism specifically refers to an electromagnetic brake (holding brake), integrated at the rear of the servo motor. When the "lock trigger logic circuit" is activated, the electromagnetic brake locks the motor shaft, ensuring absolute stillness.

[0071] In step 4, before the formal measurement, the calculation drive unit 3 synchronously reads the final static attitude data (dual-axis electronic tilt sensor) and the extension length data of the three telescopic push rods. The calculation drive unit 3 runs the embedded program to construct a spatial coordinate transformation model. The construction of the spatial coordinate transformation model includes:

[0072] Step 4-1: Define the coordinate system: Define the geodetic horizontal datum as the global coordinate system. The current plane of tray 2 is a local coordinate system. ;

[0073] Step 4-2: Constructing the rotation matrix: Based on the pitch and roll angle data measured in real time by the azimuth feedback unit 8, the drive unit 3 constructs a local coordinate system. Convert coordinates in the local coordinate system to the global coordinate system The required rotation matrix containing pitch and roll angle information ;

[0074] Step 4-3: Construct the translation vector: Based on the length data of each adjustment support component 6, calculate the translation vector in the local coordinate system. The geometric center of the photoelectric precision target testing system, based on the global coordinate system, is located in the global coordinate system. vertical displacement vector ;

[0075] Step 4-4: Establish coordinate transformation relationship: based on rotation matrix and vertical displacement vector Constructing from a local coordinate system To the global coordinate system The complete spatial transformation relationship is expressed as: ,in Indicates the photoelectric precision test target system in the global coordinate system The corrected attitude and altitude deviation measurements are as follows. This indicates the photoelectric precision testing target system in the local coordinate system. The output is the original measurement value.

[0076] Rotation matrix Used for spatial coordinate transformation and error correction, it can convert the acquired tilt data before correction into a standard horizontal coordinate system. The solution drive unit will calculate the rotation matrix in real time. and vertical displacement vector As corrective data is output to the test system, the original test system will automatically offset the error caused by the tilt in its internal algorithm.

[0077] During measurement, the photoelectric precision target testing system is activated to perform projectile density testing. The photoelectric precision target testing system calls the aforementioned spatial coordinate transformation parameters to automatically offset the pointing errors caused by the tilt and height changes of the adjustment device, ensuring that the final output landing point coordinates and projectile trajectory data meet the accuracy index (≤5 arcminutes).

[0078] Compared with the prior art, the present invention has the following significant advantages:

[0079] Possessing multi-dimensional attitude adjustment capabilities, this invention significantly enhances adaptability to extreme terrain: Unlike traditional single-axis hinge structures that can only achieve pitch adjustment in one dimension, this invention employs a parallel drive structure based on the three-point plane principle. Through the coordinated differential extension and retraction of the three adjustment support components 6, the adjustment device can not only achieve pitch adjustment of ±12° along the central axis of the field of view, but also simultaneously correct for roll deviation caused by the lateral slope of the ground. This "all-round attitude adaptability" enables the testing system to adapt to uneven deployment areas such as mountains and ravines, allowing for the rapid construction of an ideal measurement field of view without the need for a flat surface, greatly expanding the operational and testing environment applicability of the optoelectronic precision target.

[0080] With a streamlined structure and stable load-bearing capacity, this invention eliminates wear and misalignment associated with mechanical hinges. It abandons the complex mechanical hinge shaft design, instead employing a direct load-bearing mode of "integrated load-bearing platform + three sets of rigid supports." The three sets of supports are distributed in an isosceles triangle, forming a stable mechanical support system. Compared to the "cantilever" stress risk of hinge structures, the center of gravity of this design is easier to control. Combined with the adaptive universal base 1, it provides stronger grip on soft or uneven ground in the field. Simultaneously, the self-locking characteristics of the precision lead screw and the dual protection of the electronic locking mechanism ensure absolute rigidity and stillness of the posture during testing.

[0081] The "non-destructive" split design ensures perfect compatibility with existing equipment and reduces upgrade costs: This invention features a split, optional design concept, allowing the adjustment device to be used with existing CCD convergence photoelectric precision target testing systems. The pre-set mounting interface on the center surface of the integrated support platform precisely fits the protrusions and mounting holes on the bottom of existing CCD convergence photoelectric precision target testing systems. Users do not need to disassemble, drill, or modify the circuitry of the expensive original testing system; the upgrade can be completed in just two steps: "placement and fixation." This solves the problems of high risk, long cycle, and high cost associated with traditional integrated retrofitting, making it highly valuable for widespread adoption.

[0082] Hardware and software collaborative "spatial inverse kinematics" correction ensures high-fidelity measurement data: This invention constructs a hardware and software closed-loop correction system to address the complex spatial position changes (angle deflection + height rise and fall) caused by three sets of differential drives. Hardware closed loop: A dual-axis electronic tilt sensor monitors pitch and roll in real time, working with the calculation drive unit 3 to ensure precise execution of the physical attitude without unexpected distortion. Algorithm correction: The calculation drive unit 3 incorporates a spatial rigid body transformation algorithm, which not only corrects angle errors but also calculates and compensates for changes in lens center height (translation) caused by the extension and retraction of the telescopic push rod. This in-depth mathematical correction ensures that even with significant tilting of the adjustment device, the output landing point coordinates still meet the original strict accuracy target of ≤5 arcminutes, achieving "flexible attitude changes, but accurate data."

[0083] Intelligent and fully automated operation significantly reduces the barrier to manual operation: This adjustment device integrates fully automated logic for "automatic leveling, automatic angle finding, and automatic locking." Operators do not need complex surveying knowledge; they only need to input the target angle, and the calculation drive unit 3 can automatically command three servo motors to coordinate their movements through inverse kinematics calculations. An audible and visual alarm system prevents the risk of tipping over due to misoperation. This completely changes the inefficient traditional method of relying on repeated manual screw tightening for leveling, significantly improving the efficiency of field testing.

[0084] Finally, it should be noted that the features mentioned and / or shown in the above description of exemplary embodiments of the present invention can be combined in the same or similar manner with one or more other embodiments, combined with features in other embodiments, or substituted for corresponding features in other embodiments. These combined or substituted technical solutions should also be considered to be included within the scope of protection of the present invention.

Claims

1. A central axis tilt angle adjustment device for a photoelectric precision target testing system, characterized in that, include: A support platform is used to support the photoelectric precision test target system. The support platform includes a tray (2) and the tray (2) is provided with a plurality of positioning interfaces (21) that match the bottom protrusion of the photoelectric precision test target system. Adjust the support assembly (6) and arrange multiple sets evenly around the circumference of the tray (2). Each set of the adjustment support assembly (6) includes a telescopic push rod and a base (1). The upper end of the telescopic push rod is hinged to the tray (2) through a first hinge (5). The first hinge (5) restricts the rotational freedom of the telescopic push rod around its own axis. The lower end of the telescopic push rod is hinged to the base (1) through a second hinge (7). The base (1) is used to fix it to the ground. The telescopic push rod is used to adjust the target length of the adjustment support assembly (6) so that the tray (2) tilts according to the target tilt angle. A azimuth feedback unit (8) is fixed to the bottom surface of the pallet (2) and is used to monitor the pitch angle and roll angle of the pallet (2) relative to the horizontal plane of the ground. The calculation drive unit (3) is electrically connected to the azimuth feedback unit (8) and the adjustment support assembly (6) respectively. It is used to receive the pitch angle and roll angle data monitored by the azimuth feedback unit (8) and control the extension and retraction of the adjustment support assembly (6). The calculation drive unit (3) calculates the target length of each set of adjustment support assemblies (6) based on the target tilt angle of the set support plate (2) and the pitch angle and roll angle monitored by the azimuth feedback unit (8). Based on the pitch angle, roll angle and the length data of each adjustment support assembly (6), it constructs coordinate transformation parameters for converting the measurement values ​​of the photoelectric precision test target system from the support plate (2) coordinate system to the geodetic horizontal coordinate system, so as to realize the automatic correction of system error.

2. The central axis tilt angle adjustment device according to claim 1, characterized in that, The adjustment support assembly (6) is provided in three sets, and the three sets of adjustment support assemblies (6) are distributed on the three vertices of an isosceles triangle with the geometric center of the tray (2) as the center of symmetry.

3. The central axis tilt angle adjustment device according to claim 1 or 2, characterized in that, The telescopic push rod includes an electric push rod and a support rod; the adjustment support assembly (6) also includes a placement platform (4) set parallel to the support plate (2); the upper end of the electric push rod is hinged to the support plate (2) and the lower end is welded to the top surface of the placement platform (4); the upper end of the support rod is welded to the bottom surface of the placement platform (4) and the lower end is hinged to the base (1); the calculation drive unit (3) is fixed on the placement platform (4).

4. The central axis tilt angle adjustment device according to claim 3, characterized in that, The first hinge (5) is a Hooke hinge, and the second hinge (7) is a ball hinge; The upper end of the electric push rod is hinged to the support plate (2) via a Hooke hinge, and the lower end of the support rod is hinged to the base (1) via a ball joint.

5. The central axis tilt angle adjustment device according to claim 3, characterized in that, The calculation and driving unit (3) integrates a sensor communication interface, a PWM motor drive circuit, a lock trigger logic circuit, and an embedded calculation processor. The sensor communication interface is used to read the extension amount of the electric push rod in real time. The PWM motor drive circuit is used to drive the electric push rod to run. The lock trigger logic circuit is used to lock the electric push rod. The embedded calculation processor is connected to the sensor communication interface, the PWM motor drive circuit, and the lock trigger logic circuit respectively. It is used to receive the signal transmitted by the sensor communication interface and calculate the target length and correction parameters of each group of adjustment support components (6), and send control signals to the PWM motor drive circuit and the lock trigger logic circuit.

6. The central axis tilt angle adjustment device according to claim 1, characterized in that, The orientation feedback unit (8) includes a signal conditioning circuit and a sensor measurement component. The sensor measurement component is electrically connected to the signal conditioning circuit. The sensor measurement component is used to collect the pitch angle and roll angle of the pallet in real time. The signal conditioning circuit integrates a filtering algorithm to eliminate interference and smooth the data.

7. A method for adjusting the tilt angle of the central axis of a photoelectric precision target testing system, comprising adjusting the tilt angle using the central axis tilt angle adjustment device according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1, Device setup and system installation: Fix the adjustment support assembly (6) to the predetermined position at the test site via the base (1), and then place the photoelectric precision target test system on the support platform; Step 2, Target attitude calculation: Based on the on-site terrain and test requirements, determine the target tilt angle and input it into the calculation drive unit (3). The calculation drive unit (3) uses spatial geometry algorithm to calculate the target length of each adjustment support component (6) based on the geometric coordinate position of each telescopic push rod at the bottom of the support plate (2). Step 3, Differential drive: The calculation drive unit (3) adjusts the extension and retraction of each telescopic push rod based on the target length of each adjustment support component (6) so that the adjustment support component (6) can smoothly reach the target posture; Step 4: Constructing a coordinate transformation model and error compensation: Based on the pitch angle, roll angle and current length data of each adjustment support component (6) monitored in real time by the azimuth feedback unit (8), the solution driving unit (3) establishes a spatial coordinate transformation model from the local coordinate system based on the current plane of the pallet (2) to the global coordinate system based on the earth's horizontal plane, and generates spatial coordinate transformation parameters for correcting the measurement values ​​of the photoelectric precision target test system, so as to realize the automatic correction of system errors.

8. The tilt angle adjustment method according to claim 7, characterized in that, Step 4, the construction of the spatial coordinate transformation model includes: Step 4-1: Define the coordinate system: Define the geodetic horizontal datum as the global coordinate system. The current plane of the pallet (2) is a local coordinate system. ; Step 4-2, Constructing the rotation matrix: Based on the pitch and roll angle data measured in real time by the azimuth feedback unit (8), the driving unit (3) constructs a local coordinate system. Convert coordinates in the local coordinate system to the global coordinate system The required rotation matrix containing pitch and roll angle information ; Step 4-3: Construct translation vector: Based on the length data of each adjustment support component (6), calculate the translation vector in the local coordinate system. The geometric center of the photoelectric precision target testing system, based on the global coordinate system, is located in the global coordinate system. vertical displacement vector ; Step 4-4: Establish coordinate transformation relationship: based on rotation matrix and vertical displacement vector Constructing from a local coordinate system To the global coordinate system The complete spatial transformation relationship is expressed as: ,in Indicates the photoelectric precision test target system in the global coordinate system The corrected attitude and altitude deviation measurements are as follows. This indicates the photoelectric precision testing target system in the local coordinate system. The output is the original measurement value.

9. The tilt angle adjustment method according to claim 7 or 8, characterized in that, In step 3, during the extension and retraction of the telescopic push rod, the calculation drive unit (3) detects the actual length of each adjustment support component (6) in real time, and compares the actual length with the target length in real time and adjusts it with PID to ensure that the adjustment support component (6) reaches the target posture.

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