Double-beam differential laser velocity measurement system

Abstract

The invention relates to the field of laser velocity measurement, in particular to a double-beam differential laser velocity measurement system, which comprises a laser emission module, a beam splitting module, a measurement light path module, a signal acquisition and processing module and a platform. Through the double-beam differential principle, interference factors such as ambient light and laser power fluctuation are effectively counteracted, and compared with traditional single-beam laser speed measurement, the precision is remarkably improved; the adjustable structure of the measuring light path module and the optimal design of the whole system on different measured objects and working conditions can be widely applied to various fields; the temperature control and wavelength monitoring feedback of the laser emission module, the light intensity monitoring and feedback adjustment of the light beam splitting module and the cooperative work of all the modules ensure that all parameters of the system are stable and the measurement result is reliable in the long-time operation process; the signal acquisition and processing module not only can acquire speed data in real time, but also has storage and transmission functions.

Description

Technical Field

[0001] The invention relates to the field of laser speed measurement, and in particular to a double-beam differential laser speed measurement system. Background Art

[0002] Accurately measuring the speed of objects or fluids is crucial in many fields such as industrial production, fluid mechanics research, and transportation. Traditional speed measurement methods, such as mechanical tachometers and electromagnetic flowmeters, have many limitations in terms of accuracy, response speed, and scope of application.

[0003] Mechanical tachometers are susceptible to wear, their accuracy decreases with time of use, and it is difficult to accurately measure the speed of tiny or high-speed moving objects; electromagnetic flow meters are not suitable for non-conductive media, have high installation requirements, and are susceptible to external electromagnetic interference; laser speed measurement technology has gradually become a research hotspot due to its advantages of high precision, non-contact, and fast response.

[0004] However, the existing laser speed measurement systems still have some problems. For example, single-beam laser speed measurement is easily disturbed by ambient light, the measurement stability is insufficient, and the speed measurement accuracy for complex flow fields or high-speed variable speed moving objects needs to be improved.

[0005] Therefore, those skilled in the art provide a dual-beam differential laser speed measurement system to solve the problems raised in the above background technology. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a dual-beam differential laser speed measurement system.

[0007] It comprises a laser emission module, a beam splitter module, a measuring optical path module, a signal acquisition and processing module and a platform. The laser emission module, the beam splitter module, the measuring optical path module and the signal acquisition and processing module are all connected and arranged at the upper end of the platform.

[0008] Laser emission module: A high-stability, wavelength-tunable laser is selected, which can output a laser beam with stable power and high beam quality, providing a reliable light source for the entire speed measurement system; it is equipped with a temperature control device that can accurately control the operating temperature of the laser, reduce wavelength drift caused by temperature fluctuations, ensure the stability of the laser wavelength, and thus ensure the speed measurement accuracy.

[0009] Beam splitter module: A high-precision beam splitter is used to accurately split the single laser beam emitted by the laser emission module into two sub-beams with similar intensities according to a predetermined ratio; the splitting ratio of the beam splitter is strictly calibrated and the error is controlled within a very small range to ensure the accuracy of subsequent differential measurements; these two sub-beams serve as the basic beams for measurement and enter different measurement optical paths respectively.

[0010] Measurement optical path module: contains two carefully designed optical paths, namely the reference optical path and the measurement optical path;

[0011] The reference optical path is relatively simple and has a stable environment. Its length is fixed and accurately calibrated to provide a stable reference optical signal.

[0012] The measuring optical path is flexibly arranged according to the motion characteristics of the measured object or fluid, so that its light beam can interact with the measured target:

[0013] For example, when measuring the flow rate of a fluid, the light beam of the measuring optical path is incident into the fluid at a specific angle. When the fluid flows, the optical path of the light beam changes due to factors such as changes in the refractive index of the fluid and particle scattering. Highly sensitive photodetectors are set at the ends of both optical paths to convert optical signals into electrical signals;

[0014] Signal acquisition and processing module: connected to the photoelectric detector in the measurement optical path module, and collects the electrical signals output by the two photoelectric detectors in real time; the module has a built-in high-speed data acquisition card, which can capture subtle changes in electrical signals at an extremely high sampling frequency to ensure that no key information is lost; at the same time, it is equipped with a powerful signal processing algorithm to perform differential operations on the two collected signals, and by comparing the difference between the reference optical path signal and the measurement optical path signal, it can effectively offset common mode noise such as ambient light interference and laser power fluctuations, and accurately extract the optical path change information caused by the movement of the object being measured, and then calculate the speed of the object being measured based on the corresponding relationship between the optical path change and the speed.

[0015] Furthermore, the laser in the laser emission module is also connected to a wavelength monitoring feedback unit, which monitors the output wavelength of the laser in real time. Once the wavelength deviates from the set value, it immediately feeds back to the temperature control device and the laser driving circuit, automatically adjusting the temperature and driving current to ensure real-time and precise control of the wavelength.

[0016] Furthermore, the beam splitting module is provided with a light intensity monitor after the beam splitter to monitor the intensity of the two sub-beams after splitting in real time. If it is found that the intensity difference exceeds the allowable range, the angle of the beam splitter is fine-tuned or the beam splitter is replaced through the feedback control system to ensure the consistency of the intensity of the two beams and maintain the high-precision foundation of differential measurement.

[0017] Furthermore, the measuring optical path in the measuring optical path module adopts an adjustable structure, which can conveniently and quickly adjust the angle, height and focusing degree of the optical path according to different measurement scenarios, such as different measurement distances, sizes and shapes of the objects being measured, thereby achieving adaptive measurement of a variety of complex working conditions.

[0018] Furthermore, the signal acquisition and processing module also has data storage and transmission functions, which can store the measured speed data and related system operating parameters in real time in the built-in memory, and can send the data to external monitoring equipment via wired or wireless transmission, facilitating subsequent data analysis, remote monitoring and management.

[0019] Technical effects and advantages of the present invention:

[0020] 1. High-precision measurement: Through the dual-beam differential principle, it can effectively offset interference factors such as ambient light and laser power fluctuations. Compared with traditional single-beam laser speed measurement, the accuracy is significantly improved, which can meet the needs of high-precision speed measurement, such as the speed measurement of tiny parts in precision instrument manufacturing, and the flow rate measurement in high-end fluid mechanics experiments.

[0021] 2. Strong adaptability: The adjustable structure of the measuring optical path module and the optimized design of the system as a whole for different measured objects and working conditions enable it to be widely used in a variety of fields, whether it is measuring the linear motion and rotational motion of solid objects or the flow velocity of fluids of different properties.

[0022] 3. Good stability: The temperature control and wavelength monitoring feedback of the laser emission module, the light intensity monitoring and feedback adjustment of the beam splitter module, and the collaborative work between the modules ensure that the system parameters are stable during long-term operation, the measurement results are reliable, and the measurement errors caused by system drift are reduced.

[0023] 4. Real-time monitoring and data processing: The signal acquisition and processing module can not only obtain speed data in real time, but also has storage and transmission functions, which facilitates subsequent data analysis, tracing and remote monitoring, and meets the requirements of modern industrial production and scientific research for data management. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall process of a dual-beam differential laser speed measurement system provided in an embodiment of the present application;

[0025] Figure 2 It is a flow chart of a laser emission module in a dual-beam differential laser speed measurement system provided in an embodiment of the present application;

[0026] Figure 3 It is a flow chart of a laser beam splitting module in a dual-beam differential laser speed measurement system provided in an embodiment of the present application;

[0027] Figure 4 It is a flow chart of a measuring optical path module in a dual-beam differential laser speed measurement system provided in an embodiment of the present application;

[0028] Figure 5It is a flow chart of a signal acquisition and processing module in a dual-beam differential laser speed measurement system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0030] Example 1

[0031] See also Figures 1 to 5 In this embodiment, a dual-beam differential laser speed measurement system is provided, including a laser emission module, a beam splitter module, a measurement optical path module, a signal acquisition and processing module, and a platform. The laser emission module, the beam splitter module, the measurement optical path module, and the signal acquisition and processing module are all connected to the upper end of the platform.

[0032] Laser emission module: A high-stability, wavelength-tunable laser is selected to output a laser beam with stable power and high beam quality, providing a reliable light source for the entire speed measurement system. It is equipped with a temperature control device that can accurately control the operating temperature of the laser, reduce wavelength drift caused by temperature fluctuations, ensure the stability of the laser wavelength, and thus guarantee the speed measurement accuracy.

[0033] Beam splitter module: A high-precision beam splitter is used to accurately split the single laser beam emitted by the laser emission module into two sub-beams with similar intensities according to a predetermined ratio. The splitting ratio of the beam splitter is strictly calibrated, and the error is controlled within a very small range to ensure the accuracy of subsequent differential measurements. The two sub-beams serve as the basic beams for measurement and enter different measurement optical paths respectively.

[0034] Measurement optical path module: Contains two carefully designed optical paths, namely the reference optical path and the measurement optical path. The reference optical path is relatively simple and environmentally stable. Its length is fixed and accurately calibrated to provide a stable reference optical signal. The measurement optical path is flexibly arranged according to the motion characteristics of the object or fluid being measured so that its light beam can interact with the target being measured. For example, when measuring the flow rate of the fluid, the light beam of the measurement optical path is incident on the fluid at a specific angle. When the fluid flows, the light beam will change its optical path due to factors such as changes in the refractive index of the fluid and particle scattering. Highly sensitive photodetectors are set at the ends of both optical paths to convert optical signals into electrical signals.

[0035] Signal acquisition and processing module: connected to the photodetector in the measurement optical path module, real-time acquisition of electrical signals output by two photodetectors. The module has a built-in high-speed data acquisition card that can capture subtle changes in electrical signals at an extremely high sampling frequency to ensure that no key information is lost. At the same time, it is equipped with a powerful signal processing algorithm to perform differential operations on the two collected signals. By comparing the difference between the reference optical path signal and the measurement optical path signal, it effectively offsets common mode noise such as ambient light interference and laser power fluctuations, accurately extracts the optical path change information caused by the movement of the object being measured, and then calculates the speed of the object being measured based on the corresponding relationship between the optical path change and the speed.

[0036] The laser in the laser emission module is also connected to a wavelength monitoring feedback unit, which monitors the output wavelength of the laser in real time. Once the wavelength deviates from the set value, it immediately feeds back to the temperature control device and the laser drive circuit, automatically adjusting the temperature and drive current to ensure real-time and accurate control of the wavelength.

[0037] The beam splitting module is equipped with a light intensity monitor after the beam splitter to monitor the intensity of the two sub-beams after splitting in real time. If the intensity difference is found to be beyond the allowable range, the feedback control system will fine-tune the angle of the beam splitter or replace the beam splitter to ensure the consistency of the intensity of the two beams and maintain the high-precision foundation of differential measurement.

[0038] The measuring optical path in the measuring optical path module adopts an adjustable structure, which can quickly and easily adjust the angle, height and focusing degree of the optical path according to different measurement scenarios, such as different measurement distances, sizes and shapes of measured objects, to achieve adaptive measurement of various complex working conditions.

[0039] The signal acquisition and processing module also has data storage and transmission functions, which can store the measured speed data and related system operating parameters in real time in the built-in memory, and can send the data to external monitoring equipment via wired or wireless transmission to facilitate subsequent data analysis, remote monitoring and management.

[0040] When using the present invention, firstly, in the system initialization stage, the laser emission module is turned on, the temperature control device stabilizes the laser operating temperature at the set value, and the wavelength monitoring feedback unit monitors the laser wavelength in real time to ensure that the initial wavelength is accurate; the beam splitting module completes the splitting operation, and the light intensity monitor checks the intensity of the two sub-beams to ensure that it is within the allowable error range. If there is a deviation, it is adjusted in time. The measuring optical path module pre-adjusts the various parameters of the measuring optical path according to the characteristics of the measured object. For example, when measuring the flow rate of a fluid, the measuring optical path beam is aligned with the fluid flow area at a suitable angle, and the reference optical path ensures stability without interference.

[0041] When the measurement starts, the laser emission module continuously outputs a stable laser beam. After splitting, the two sub-beams enter the reference optical path and the measurement optical path respectively. In the measurement optical path, the light beam interacts with the object or fluid being measured, and the optical path changes. The photodetectors at the ends of the two optical paths convert the optical signal into an electrical signal in real time. The signal acquisition and processing module collects the two electrical signals at a high-speed sampling frequency, performs differential operations through built-in algorithms, offsets common-mode interference, and extracts effective speed information. For example, when measuring the surface speed of a high-speed rotating mechanical component, the measurement light path beam irradiates the surface of the component. As the component rotates, the slight fluctuations, roughness, and reflection characteristics of the surface change rapidly and complexly, causing the optical path to change. The signal acquisition and processing module, with its high sampling rate and precise algorithm, accurately captures these changes and converts them into speed values.

[0042] During the entire measurement process, the signal acquisition and processing module continuously stores the measurement data and transmits it on demand. If an abnormal situation occurs, such as a sudden change in signal or abnormal intensity, the system automatically issues an alarm to prompt the operator to check the system. At the same time, the feedback adjustment mechanism of each module continues to operate to ensure that the laser wavelength, beam splitting ratio, optical path status, etc. are always in the best state, ensuring high accuracy and stability of the measurement.

[0043] Through the above implementation methods, the dual-beam differential laser speed measurement system of the present invention can achieve high-precision and high-stability speed measurement for various objects and fluids in complex and changeable environments, providing strong technical support for many fields such as industrial production and scientific research.

[0044] The electrical components appearing in this article are all electrically connected to an external main controller and 220V AC power, and the main controller can be a conventional known device that controls a computer, etc. The specific implementation method of the present disclosure omits the detailed description of known functions and known components. To ensure the compatibility of the equipment, the operating methods used are consistent with the parameters of marketed equipment.

[0045] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A dual-beam differential laser speed measurement system, characterized in that: include: A laser emission module, wherein the laser emission module uses a high-stability, wavelength-tunable laser and is equipped with a temperature control device. The laser outputs a laser beam with stable power and high beam quality, and the laser is connected to a wavelength monitoring feedback unit for real-time monitoring and adjustment of the laser output wavelength; A beam splitting module, which uses a high-precision beam splitter to split the single laser beam emitted by the laser emission module into two sub-beams with similar intensities according to a predetermined ratio. A light intensity monitor is arranged behind the beam splitter to monitor and adjust the intensities of the two sub-beams; A measuring optical path module, wherein the measuring optical path module comprises a fixed reference optical path and a measuring optical path that can be flexibly arranged according to the motion characteristics of the measured object or fluid, and a high-sensitivity photoelectric detector is provided at the end of both optical paths, and the measuring optical path adopts an adjustable structure; A signal acquisition and processing module, which is connected to the photoelectric detector and has a built-in high-speed data acquisition card and a powerful signal processing algorithm, is used to acquire and differentially operate two electrical signals to extract speed information, and has data storage and transmission functions; The platform, the laser emission module, the beam splitting module, the measurement optical path module and the signal acquisition and processing module are all placed on the upper end of the platform.

2. A dual-beam differential laser speed measurement system according to claim 1, characterized in that: The temperature control device of the laser emission module accurately controls the operating temperature of the laser and controls the temperature fluctuation within a very small range.

3. A dual-beam differential laser speed measurement system according to claim 1, characterized in that: The beam splitting ratio error of the beam splitter of the beam splitting module is controlled within a very small range.

4. A dual-beam differential laser speed measurement system according to claim 1, characterized in that: The measuring light path of the measuring light path module can adjust the angle, height and focusing degree of the light beam of the light path according to different measuring scenes.

5. A dual-beam differential laser speed measurement system according to claim 1, characterized in that: The signal acquisition and processing module can capture subtle changes in electrical signals at an extremely high sampling frequency, offset common-mode noise through differential operations, and accurately extract information on optical path changes caused by the movement of the object being measured.

6. A dual-beam differential laser speed measurement system according to claim 1, characterized in that: The signal acquisition and processing module includes a built-in processor, and the signal acquisition and processing module stores the measured speed data and related system operating parameters in a built-in memory in real time.

7. A dual-beam differential laser speed measurement system according to claim 6, characterized in that: It also includes an external monitoring device, which is used to receive data collected by the signal collection and processing module.

8. A dual-beam differential laser speed measurement system according to claim 7, characterized in that: The signal acquisition and processing module sends the signal to the external monitoring device via wired or wireless transmission.

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