A capillary viscometer vertical alignment automatic adjustment device

Abstract

The invention discloses a capillary viscometer vertical alignment automatic adjustment device, comprising an inclination recognition module, an intelligent inclination adjustment module, an angle adjustment platform, a capillary viscometer, a mechanical joint, a constant temperature viscosity water tank detection port and a constant temperature capillary viscosity water tank, wherein the inclination recognition module, the intelligent inclination adjustment module and the angle adjustment platform are all arranged on the top of the constant temperature capillary viscosity water tank, the top of the constant temperature capillary viscosity water tank is provided with a capillary viscosity water tank detection port, the capillary viscosity water tank detection port is used to insert the capillary viscometer, the angle adjustment platform and the inclination recognition module form a whole, and the intelligent inclination adjustment module is connected to the inclination recognition module through a mechanical joint. The invention reduces the need for manual operation through an automated adjustment process, greatly improves measurement efficiency, reduces the need for equipment calibration and maintenance, and reduces related costs and downtime.

Description

Technical Field

[0001] The invention relates to the field of measurement technology, and in particular to a capillary viscometer vertical alignment automatic adjustment device. Background Art

[0002] Existing capillary viscometers usually include a capillary filled with a test liquid, and the viscosity is calculated by measuring the rate at which the liquid flows through the capillary. In order to achieve the vertical placement of the capillary viscometer, most existing devices fix the capillary viscometer by using a fixed bracket, a vertical fixing card, a vertical adjustment fixture, etc. The device usually requires manual adjustment to achieve vertical alignment to ensure the accuracy of the measurement. However, this manual adjustment method is time-consuming and easily affected by the operator's skills, resulting in the accuracy of the measurement results being easily affected.

[0003] The rigid fixing bracket and vertical fixing card are factory defaults that the fixing device and the capillary viscometer used are in a vertical state, and cannot automatically detect the vertical state changes during actual use, and cannot monitor and make changes in real time during the test. Although the elastic clamp used in the vertical adjustment fixture with the inclination sensor can achieve real-time monitoring and adjustment, it detects the inclination of the fixture that fixes the capillary viscometer. If there is a slight change perpendicular to the inclination detector due to the rotation or deformation of the fixture, the solution cannot respond in time.

[0004] In view of the above problems, the present invention provides a capillary viscometer vertical alignment automatic adjustment device which improves the measurement accuracy and repeatability. Summary of the invention

[0005] The invention provides a capillary viscometer vertical alignment automatic adjustment device which improves measurement accuracy and repeatability.

[0006] The invention aims to provide a capillary viscometer vertical alignment automatic adjustment device, comprising an inclination recognition module, an intelligent inclination adjustment module, an angle adjustment platform, a capillary viscometer, a mechanical joint, a constant temperature viscosity water tank detection port and a constant temperature capillary viscosity water tank, wherein the inclination recognition module, the intelligent inclination adjustment module and the angle adjustment platform are all arranged on the top of the constant temperature capillary viscosity water tank, the top of the constant temperature capillary viscosity water tank is provided with a capillary viscosity water tank detection port, the constant temperature viscosity water tank detection port is used to insert the capillary viscometer, the angle adjustment platform and the inclination recognition module form a whole, and the intelligent inclination adjustment module is connected to the inclination recognition module through a mechanical joint.

[0007] Furthermore, the mechanical joint includes a mechanical joint connecting seat, a universal cross shaft, a Y-axis fixing buckle, a Z-axis fixing buckle, an X-axis support and a Z-axis rotation module. The universal cross shaft is connected to the Y-axis fixing buckle and the Z-axis fixing buckle. The universal cross shaft, the Y-axis fixing buckle and the Z-axis fixing buckle are all arranged on the mechanical joint connecting seat. One end of the X-axis support is connected to the universal cross shaft, and the other end of the X-axis support is connected to the X-axis rotation module.

[0008] Furthermore, the inclination recognition module includes a cold light source, a liquid level standard module and a detector, the liquid level standard module is arranged on the detector, and the cold light source is arranged on the liquid level standard module.

[0009] Furthermore, the intelligent tilt adjustment module includes a microprocessor, a micro motor and a communication interface, and the microprocessor, the micro motor and the communication interface are all integrated in the intelligent tilt adjustment module.

[0010] The present invention has the following advantages:

[0011] The present invention reduces the need for manual operation through the automated adjustment process, greatly improving the measurement efficiency. It reduces the need for equipment calibration and maintenance, reduces related costs and downtime, and can reduce fluctuations introduced by human factors through the automatic adjustment device, more accurately achieve vertical alignment of the capillary viscometer, thereby improving the accuracy and repeatability of the measurement.

[0012] The present invention utilizes the principle of the rectilinear propagation of light and the refraction occurring in different media, combines a light source detector and an angle adjustment device, and realizes real-time monitoring of the vertical situation of the capillary viscometer during the detection process. It is corrected by means of an intelligent inclination adjustment module, and real-time adjustments can be made to the changes during the experiment. In addition, information transmission through the optical path reduces the measurement error caused by slight physical changes of the fixture. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a front view of the present invention;

[0014] Figure 2 A top view of the present invention;

[0015] Figure 3 It is a schematic diagram of the mechanical joint structure of the present invention.

[0016] In the figure: 1. cold light source; 2. liquid level standard module; 3. detector; 4. capillary viscometer; 5. constant temperature capillary viscosity water tank; 6. angle adjustment table; 7. inclination recognition module; 8. intelligent inclination adjustment module; 9. mechanical joint; 10. constant temperature capillary viscosity water tank; 11. universal cross axis; 12. Y-axis fixing buckle; 13. Z-axis fixing buckle; 14. X-axis support; 15. X-axis rotation module; 16. mechanical joint connector; 17. micro motor; 18. microprocessor; 19. communication interface. DETAILED DESCRIPTION

[0017] The present invention provides a capillary viscometer vertical alignment automatic adjustment device, comprising an inclination recognition module 7, an intelligent inclination adjustment module 8, an angle adjustment platform 6, a capillary viscometer 4, mechanical joints 9, 5 and a constant temperature capillary viscosity water tank 5, wherein the inclination recognition module 7, the intelligent inclination adjustment module 8 and the angle adjustment platform 6 are all arranged on the top of the constant temperature capillary viscosity water tank 5, a capillary viscosity water tank detection port is provided on the top of the constant temperature capillary viscosity water tank 5, the constant temperature viscosity water tank detection port 5 is used to insert the capillary viscometer 4, the angle adjustment platform 6 and the inclination recognition module 7 form a whole, and the intelligent inclination adjustment module 8 is connected to the inclination recognition module 7 through the mechanical joint 9.

[0018] In this embodiment, the mechanical joint 9 includes a mechanical joint 9 connecting seat, a universal cross shaft 11, a Y-axis fixing buckle 12, a Z-axis fixing buckle 13, an X-axis support 14 and a Z-axis rotation module. The universal cross shaft 11 is connected to the Y-axis fixing buckle 12 and the Z-axis fixing buckle 13. The universal cross shaft 11, the Y-axis fixing buckle 12 and the Z-axis fixing buckle 13 are all arranged on the mechanical joint 9 connecting seat. One end of the X-axis support 14 is connected to the universal cross shaft 11, and the other end of the X-axis support 14 is connected to the X-axis rotation module 15.

[0019] In this embodiment, the inclination recognition module 7 includes a cold light source 1, a liquid level standard module 2 and a detector 3. The liquid level standard module 2 is arranged on the detector 3, and the cold light source 1 is arranged on the liquid level standard module 2.

[0020] In this embodiment, the intelligent tilt adjustment module 8 includes a microprocessor 18 , a micro motor 17 and a communication interface 19 , and the microprocessor 18 , the micro motor 17 and the communication interface 19 are all integrated in the intelligent tilt adjustment module 8 .

[0021] In this embodiment, a cold light source 1 is irradiated to form a light spot on the plane sensor. The position of this light spot relative to the sensor origin reflects the offset of the capillary viscometer 4. First, the position of the light spot on the sensor is captured. In order to detect the light spot more accurately, the image is thresholded. Each pixel p in the image is compared with the threshold T to generate a binary image B. This converts the image into a binary image, where the light spot is usually bright and the background is dark. In the thresholded image, the light spot appears as a collection of bright pixels. Use image processing techniques (centroid calculation) to find the exact location of the light spot. After determining the location of the light spot, extract its coordinates (x, y) on the sensor plane. Where (x i ,y i ) is the coordinate of the bright pixel, and n is the total number of bright pixels. centroid ,y centroid ) is the coordinate of the light spot on the sensor plane.

[0022] In this embodiment, because the movement of the robotic arm is based on its own coordinate system rather than the coordinate system of the sensor, a coordinate transformation is performed. First, the relative position and direction between the sensor plane and the robotic arm coordinate system need to be determined. This is determined by measurement or pre-set parameters, and is set according to the actual situation on site during actual use. According to the relative position and direction between the sensor and the robotic arm, an appropriate geometric transformation is applied. This usually involves rotation and translation. By applying a transformation matrix, the coordinates of the light spot in the sensor coordinate system are converted to the coordinates in the robotic arm coordinate system. Assume that the robotic arm coordinate system is R and the transformation matrix is ​​T. The transformation matrix T contains information about rotation and translation. If the coordinates of the light spot in the sensor coordinate system are P(x, y), the coordinates P′(x′, y′) in the robotic arm coordinate system can be calculated as follows: P′=T·P, where T is a 2×2 matrix that maps the sensor coordinates to the robotic arm coordinates. For example, if the sensor is only translated relative to the robotic arm (no rotation), T can be expressed as: where t x and t y is the translation of the sensor relative to the robot in the x and y directions.

[0023] In this embodiment, the Simulink toolbox of MATLAB is used to implement a PID controller to adjust the system output and effectively control the movement of the robotic arm. The output u(t) of the PID controller can be expressed as: Among them, e(t) is the error between the current light spot position and the target position, k P is the proportional gain, which determines the controller’s response to the current error, k i is the integral gain, used to eliminate static error, k d It is the differential gain, which is used to predict the changing trend of the error and improve the stability and response speed of the system. By properly adjusting these parameters, the PID controller can effectively control the movement of the robot arm so that the light spot is stabilized at the target position of the sensor.

[0024] In this embodiment, the generation of the robot arm motion instructions involves converting the output of the PID controller into the angle change of each joint of the robot arm. This process generally includes the following steps: Inverse kinematics calculation: Based on the output of the PID controller, the angle that each joint of the robot arm needs to move is calculated. This generally involves solving the inverse kinematics equation, which is a process of inferring the angle of each joint from the position and orientation of the end of the robot arm. The joint angle change Δθ of the robot arm can be obtained by solving the inverse kinematics equation. Using the Newton-Raphson method, first an initial guess θ0 is selected, and then this guess is improved through the following iterative steps: θ k+1 =θ k -J(θ k ) -1 .f(θ k ), where J(θ k ) is the Jacobian matrix, f(θ k ) is the end position error. Through continuous iteration, the joint angle that is closer and closer to the true solution can be obtained. Command sending: Use MATLAB's serial port communication to send the calculated joint angle command to the micro motor.

[0025] In this embodiment, closed-loop control is the key to achieve precise robot arm movement. It involves implementing a real-time feedback loop that continuously reads sensor data and adjusts the position of the robot arm accordingly. This process generally includes the following steps: Data reading: Read the current position data of the light spot from the sensor in real time. Error calculation: Calculate the error between the current position of the light spot and the target position. Robot arm adjustment: According to the error signal, adjust the position of the robot arm through the PID controller. Real-time feedback: Use Simulink to implement this real-time feedback loop. The error signal e(t) in the feedback loop needs to be continuously updated to reflect the current position P of the light spot. current (x,y) and the target position P target The error signal can be expressed as: e(t) = P target (t)-P current (t), where t is time. This error signal is then fed into a PID controller to calculate the angle adjustment Δθ for each joint of the robot. In this way, the closed-loop control system ensures that the robot accurately tracks the movement of the light spot and stably positions it at the target position.

[0026] In this embodiment, when the planar detector 3 is perpendicular to the light emitted by the cold light source 1, the intersection point is set as the origin, and the detector 3 is divided into four quadrants and assigned coordinate values. After the light emitted by the cold light source 1 passes through the liquid horizontal standard mold and refracts at the air interface, the light spot will eventually fall on the plane of the detector 3. The distance and position of the light spot and the origin are calculated by the inclination recognition module 7 and the information is transmitted to the intelligent inclination adjustment module 8. With the help of the intelligent inclination adjustment module 8, the capillary viscometer 4 is perpendicular to the horizontal plane when the light signal intensity detected at the origin position of the detector 3 is the strongest. When the capillary viscometer tilts during the detection process, the signal intensity received by the detector 3 is weakened. At this time, the intelligent inclination adjustment module 8 receives the feedback signal and automatically adjusts the horizontal state of the angle adjustment platform 6 so that the light from the cold light source 1 is irradiated at the origin position of the detector 3 again, and the capillary viscometer 4 is restored to a vertical state at the same time.

[0027] In this embodiment, the intelligent tilt adjustment module 8 includes a microprocessor 18, a micro motor 17 and a communication interface 19. The microprocessor 18 is used to process the data collected by the sensor and calculate the adjustment instruction accordingly. The communication interface 19 is used to receive the signal from the detector 3 and transmit the adjustment instruction to the micro motor 17. The micro motor 17 can realize the rotation adjustment of the two angles X and Y parallel to the horizontal plane, and perform physical adjustment according to the instruction of the microprocessor 18.

[0028] Although the specific implementation of the present invention is described in detail in conjunction with the drawings, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A capillary viscometer vertical alignment automatic adjustment device, comprising an inclination recognition module, an intelligent inclination adjustment module, an angle adjustment platform, a capillary viscometer, a mechanical joint, a constant temperature viscosity water tank detection port and a constant temperature capillary viscosity water tank, characterized in that: The inclination recognition module, the intelligent inclination adjustment module and the angle adjustment platform are all arranged on the top of the constant temperature capillary viscosity water tank. The top of the constant temperature capillary viscosity water tank is provided with a capillary viscosity water tank detection port, and the constant temperature viscosity water tank detection port is used to insert a capillary viscometer. The angle adjustment platform and the inclination recognition module form a whole, and the intelligent inclination adjustment module is connected to the inclination recognition module through a mechanical joint; The mechanical joint comprises a mechanical joint connection seat, a universal cross shaft, a Y-axis fixing buckle, a Z-axis fixing buckle, an X-axis support and a Z-axis rotation module, the universal cross shaft is connected with the Y-axis fixing buckle and the Z-axis fixing buckle, the universal cross shaft, the Y-axis fixing buckle and the Z-axis fixing buckle are all arranged on the mechanical joint connection seat, one end of the X-axis support is connected with the universal cross shaft, and the other end of the X-axis support is connected with the X-axis rotation module; The inclination angle recognition module includes a cold light source, a liquid level standard module and a detector, wherein the liquid level standard module is arranged on the detector, and the cold light source is arranged on the liquid level standard module; The intelligent tilt adjustment module comprises a microprocessor, a micro motor and a communication interface, and the microprocessor, the micro motor and the communication interface are all integrated in the intelligent tilt adjustment module.

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