Ceiling fan rotating speed testing method and system

Abstract

The invention discloses a ceiling fan rotating speed test method and system, and relates to the technical field of ceiling fan rotating speed measurement, and the test method comprises the specific steps: S100, system preparation and parameter setting: starting a ceiling fan rotating speed test system, carrying out the comprehensive power-on self-test of the whole system, and inputting the number of fan blades of a ceiling fan through a product setting interface by a user; non-contact measurement is carried out through the laser pulse signals, the problem that application of a traditional rotating speed measurement method to a ceiling fan with an illuminating lamp is limited is effectively solved, remote and non-contact measurement of the rotating speed of the ceiling fan is achieved through installation of the laser transmitter and the receiver, and the measurement accuracy is improved. Errors and damage risks caused by physical contact are avoided, the application range of the measuring method is widened, in addition, due to the high sensitivity and high precision characteristics of the laser sensor, the rotating speed of the ceiling fan rotating at a high speed can be accurately measured, and the measuring accuracy and reliability are improved.

Description

Technical Field

[0001] The invention relates to the technical field of ceiling fan rotation speed measurement, and in particular to a ceiling fan rotation speed testing method and system. Background Art

[0002] Ceiling fans, as a household appliance that combines air circulation and lighting (especially ceiling fans with lighting) functions, play an indispensable role in modern home and office environments. They not only provide a cool and comfortable environment, but also serve as part of interior decoration to increase the beauty of the space. In order to ensure the efficiency and safety of ceiling fans and extend their service life, accurate measurement of ceiling fan speed is particularly important. This is not only related to the operating efficiency of ceiling fans, but also directly affects the user's actual experience.

[0003] Traditional ceiling fan speed measurement methods, such as photoelectric sensors and magnetoelectric sensors, although they can meet basic measurement needs to a certain extent, are incapable of measuring ceiling fans with lighting. These methods often require direct contact with the ceiling fan blades or the installation of specific marks on the blades, which is not only cumbersome to operate, but also easy to cause physical damage to the ceiling fan. More importantly, these methods are almost impossible to implement when there is a lighting in the middle of the ceiling fan, because the presence of the lighting greatly limits the installation position and measurement accuracy of the sensor. Therefore, the market urgently needs a new method that can accurately measure the speed of ceiling fans and avoid damage to the ceiling fans.

[0004] Therefore, a ceiling fan speed testing method and system are developed to monitor the speed changes of the ceiling fan in real time to ensure the normal operation of the ceiling fan and provide users with an intelligent usage experience. Summary of the invention

[0005] The purpose of the present invention is to make up for the shortcomings of the prior art and to provide a ceiling fan speed testing method and system. By using laser pulse signals for non-contact measurement, the application difficulties of traditional speed measurement methods on ceiling fans with lighting lamps are effectively solved. By measuring the number of pulse signals received by the laser receiver and the number of ceiling fan blades, the actual speed of the ceiling fan can be automatically calculated and intuitively displayed on the display screen.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: On the one hand, a ceiling fan speed test method, the specific steps of the test method are:

[0007] S100, system preparation and parameter setting: start the ceiling fan speed test system, conduct a comprehensive power-on self-test on the entire system, and the user enters the ceiling fan parameters through the product setting interface. According to the input installation height information, adjust the position and angle of the laser transmitter and receiver;

[0008] S200, laser emission and signal collection start: the laser transmitter emits a laser pulse signal vertically downward according to a preset frequency and intensity, and the laser receiver simultaneously starts collecting signals and records the start time;

[0009] S300, signal reception and processing: After the blades rotate to cut the laser beam, the laser receiver converts the optical signal amplification circuit into an electrical pulse signal and amplifies it, and simultaneously performs filtering, denoising and smoothing on the electrical pulse signal. The signal stability is determined by statistically analyzing the time interval of the electrical pulse signal, and abnormal signals are eliminated;

[0010] S400, speed calculation and cycle judgment: according to the pulse signal time interval and the known number of wind blades, the speed is calculated using an algorithm formula, the blade rotation cycle is judged by combining the algorithm formula with the speed value, and the calculation result is verified and corrected;

[0011] S500, dynamic calibration: real-time monitoring of the ceiling fan's cumulative operating time, ambient temperature changes, and number of consecutive measurements. When any preset calibration conditions are met, the calibration is started, and a standard rotating device with a known speed is used to run at different speeds. The laser transmitter and receiver measure and compare the speed with the standard speed to calculate the speed error, adjust the system parameters according to the speed error, and record the calibration data;

[0012] S600 real-time monitoring and early warning: Start the system, sample the ceiling fan speed in real time, record the light signal and the corresponding timestamp, calculate the ceiling fan speed change in real time, and set the speed fluctuation threshold T T , when the fluctuation range of the detected ceiling fan speed within a unit time exceeds the threshold, an early warning signal is issued to remind the user through sound, flashing lights or pop-up windows;

[0013] S700, result display and data storage: the final calculated ceiling fan speed result is displayed on the display screen, and at the same time, all relevant data in this measurement process, including the collected original signal data, the intermediate data in the calculation process, the calibration data and the final speed result are stored.

[0014] Furthermore, in the S300, the filtering, denoising and smoothing of the electric pulse signal in the signal reception and processing is performed by using a finite impulse response digital filter to perform filtering and denoising, and the amplified electric signal is assumed to be V out (t), for V out (t) is sampled, and the sampling frequency is f s , the number of sampling points is N, and the discrete signal sequence is v out [n], n = 0, 1, ..., N-1, the coefficient of the finite impulse response digital filter is h[k], k = 0, 1, ..., M-1, M is the filter order, and the calculation formula of the filtered signal y[n] is: The moving average method is used to smooth the electric pulse signal. Assuming the moving average window length is L, the smoothed signal s[n] is:

[0015] Furthermore, in the above S300, the signal stability is determined by statistically analyzing the time interval of the electric pulse signal during signal reception and processing, and pulse detection is performed on the smoothed signal s[n]. When s[n] exceeds the pulse detection threshold V th When a pulse is detected, the sampling point number n corresponding to the rising or falling edge of each pulse is recorded. i , calculate the time interval Δt between adjacent pulses i , the formula is: where f s is the sampling frequency, and the average value of the time interval is calculated and standard deviation σ Δt , the formula is: Where K is the number of pulses detected, and the standard deviation σ Δt Exceeding the preset deviation threshold σ th , thinking that the signal is unstable.

[0016] Furthermore, in the S400, the speed calculation and the cycle judgment are weighted average calculation speed, according to the processed pulse signal time interval sequence Δt i , i = 1, 2, ..., K, K is the number of pulses detected, the pulse period is calculated using the weighted average method, and the weight coefficient is set to w i , i = 1, 2, ..., K, and Weighted average pulse period T wavg The calculation formula is: Speed ​​RPM pre The calculation formula is: Where n is the number of ceiling fan blades.

[0017] Furthermore, in the above S400, the rotation speed calculation and period determination is performed by combining the rotation speed value with the formula to determine the period of blade rotation. total (n) is the total pulse signal strength integral value within n blade rotation cycles, I peak (n) is the sum of the peak values ​​of the pulse signal intensity within these n cycles, RPM pre is the speed value, T full To determine the blade rotation period, calculate the eigenvalue F related to the period period , the formula is: Determine the period T through the function g(x) full , the formula is: Where a, b, and c are constants obtained by fitting the experimental data of different types of ceiling fans.

[0018] Furthermore, in the S400, in the speed calculation and cycle judgment, the speed calculation result is verified by constructing a speed error evaluation function, assuming that the speed error evaluation function is E(RPM), and the calculation formula is: E(RPM)=Aσ Δt +BΔT+CΔH+D|RPM-RPM nom |, where σ Δt is the standard deviation of the pulse time interval, ΔT is the change in ambient temperature, ΔH is the change in ambient humidity, RPM nom is the nominal speed of the ceiling fan, A, B, C, D are weight coefficients determined by experiments, and the corrected speed RPM is calculated. corr The error evaluation value E(RPM corr ), E(RPM corr ) is less than the preset error threshold E th Assuming that the speed calculation result is accurate, RPM corr As the final speed calculation result; E (RPM corr )≥E th , then recalculate.

[0019] Furthermore, in S400, the error threshold E in the speed calculation and cycle judgment th Determine, set RPM max The maximum speed that this type of ceiling fan can reach, RPM nin is the minimum speed, k is the coefficient, and the error threshold E th The calculation formula is: E th = k × (RPM max -RPM min ).

[0020] Furthermore, in S500, the calibration condition in the dynamic calibration is:

[0021] Ceiling fan cumulative running time monitoring: set to record the cumulative running time t of the ceiling fan run , ceiling fan cumulative running time threshold t th1 , when t run ≥t th1 When , the calibration is triggered;

[0022] Ambient temperature change monitoring: every Δt temp Record a temperature value, calculate the difference ΔT between two adjacent temperature measurements, and set the ambient temperature change threshold ΔT th , when |ΔT|≥ΔT th When , the calibration is triggered;

[0023] Continuous measurement number monitoring: record the number of continuous measurements n meas , set the continuous measurement number threshold n th, when n rneas ≥n th , triggers calibration.

[0024] Furthermore, in the step S500, the calculation of the speed error and the speed error change rate in the dynamic calibration is performed based on the preset speed RPM. si The laser transmitter is operated to emit laser pulse signals, and the laser receiver collects the signals modulated by the standard rotating device and calculates the speed error ΔRPM at each preset speed. i , the formula is: ΔRPM i =RPM si -RPM mi , calculate the speed error change rate δRPM i , the formula is: Where ΔRPM i-1 It is the speed error at the last preset speed.

[0025] On the other hand, a ceiling fan speed test system includes a laser transmitter module, a laser receiver module, a signal processing module, a data calculation and analysis module, a storage module, a display module and a control module;

[0026] The laser transmitter module is composed of a laser diode, a driving circuit and an optical collimation component. Under the precise control of the driving circuit, the laser diode emits a laser that meets the specific frequency and intensity requirements, and the optical collimation component converts it into a parallel beam to provide a stable light source for the test;

[0027] The laser receiver module includes a photodetector, a preamplifier and a signal conditioning circuit. The photodetector converts the received optical signal into a weak electrical signal, which is initially amplified by the preamplifier and then filtered and shaped by the signal conditioning circuit to remove interference. The processed electrical pulse signal is transmitted to subsequent modules and the start time is recorded at the same time.

[0028] The signal processing module uses a filter to remove noise from the electrical pulse signal, uses a moving average method to smooth the signal, detects pulses, calculates the average value and standard deviation of the time intervals between adjacent pulses, determines signal stability, and removes abnormal signals;

[0029] The data calculation and analysis module calculates the pulse period according to the processed pulse time interval to obtain the preliminary rotation speed, determines the blade rotation period by analyzing the pulse signal strength related data, constructs an error evaluation function to verify the rotation speed result, and evaluates and corrects the rotation speed according to environmental factors and the nominal rotation speed;

[0030] The storage module: classifies and stores the original signal data, intermediate data, calibration data and final rotation speed results in the test through a solid state hard disk, and adds a timestamp and parameter identification;

[0031] The display module: displays the final speed test result, speed change curve, environmental parameters and system working status information through the liquid crystal display;

[0032] The control module is based on a microcontroller and coordinates the work of each module. It initializes the equipment and adjusts the parameters when the system starts, monitors the operating status during the test, starts the calibration when the calibration conditions are met, monitors the speed fluctuation and issues an early warning, and manages the storage and display modules.

[0033] Compared with the prior art, the ceiling fan speed testing method and system have the following beneficial effects:

[0034] 1. The present invention adopts laser pulse signals for non-contact measurement, which effectively solves the problem that the traditional rotation speed measurement method is limited in application on ceiling fans with lighting lamps. The present invention realizes remote, non-contact measurement of the rotation speed of the ceiling fan by installing a laser transmitter and a receiver, which not only avoids the error and damage risk caused by physical contact, but also broadens the scope of application of the measurement method. In addition, the high sensitivity and high precision characteristics of the laser sensor enable the present invention to accurately measure the rotation speed of high-speed rotating ceiling fans, thereby improving the accuracy and reliability of the measurement.

[0035] 2. The present invention introduces dynamic calibration technology to improve the measurement accuracy and adaptability of the present invention. In practical applications, the operating status of the ceiling fan is affected by many factors, such as changes in ambient temperature and the cumulative operating time of the ceiling fan. The present invention utilizes dynamic calibration technology to monitor these key parameters in real time. When the preset calibration conditions are met, the calibration program is automatically started, and calibration is performed using a standard rotating device with a known rotation speed, thereby effectively eliminating measurement errors. This not only enables the present invention to maintain high-precision measurements in various complex environments, but also greatly simplifies the calibration process and improves work efficiency. At the same time, by recording and storing the calibration data in a local storage unit, subsequent data analysis and system optimization are facilitated.

[0036] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 is a flow chart of a ceiling fan speed testing method;

[0039] Figure 2 The figure is a flow chart of a ceiling fan speed test system. DETAILED DESCRIPTION

[0040] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation mode, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0041] Embodiment 1:

[0042] Ceiling fan speed test in home environment

[0043] When the ceiling fan speed test system is turned on, the system automatically enters the power-on self-test program. The self-test module conducts a comprehensive inspection of the laser transmitting device, receiving device and control circuit hardware components. After confirming that all components are fault-free, a detailed self-test report is generated to ensure that the system has the basic conditions for normal operation. The user enters the number of ceiling fan blades n through the product setting interface, and enters relevant data based on the actual installation height information. The control unit accurately adjusts the position and angle of the laser transmitter and receiver based on these parameters, so that it can accurately capture the signal when the ceiling fan blades rotate.

[0044] The signal generation and acquisition module starts working according to the preset parameters. The laser generator generates a laser pulse signal with a specific frequency and intensity, which is projected vertically downward through the transmitting device. When the ceiling fan blades rotate normally, the photodetector begins to receive the light signal and quickly converts it into an electrical pulse signal. The electrical pulse signal is then amplified, filtered, and processed by the acquisition circuit, and finally the analog signal is successfully converted into a digital signal. At the same time, the start time of signal acquisition is recorded to provide a time reference for the subsequent accurate calculation of the rotation speed.

[0045] The fan blades continue to rotate and cut the laser beam. The laser receiver continuously receives the light signal and converts it into an electrical pulse signal. Let the amplified electrical signal be V out (t), for V out (t) is sampled, and the sampling frequency is f s , the number of sampling points is N, and the discrete signal sequence is v out [n], assuming that the coefficient of the finite impulse response digital filter is h[k], the calculation formula of the filtered signal y[n] is: The moving average method is used to smooth the electric pulse signal. Assuming the moving average window length is L, the smoothed signal s[n] is: Perform pulse detection on the smoothed signal s[n]. When s[n] exceeds the pulse detection threshold Vth When a pulse is detected, the sampling point number n corresponding to the rising or falling edge of each pulse is recorded. i , calculate the time interval Δt between adjacent pulses i , the formula is: Calculates the average value of a time interval and standard deviation σ Δt , the formula is: If the standard deviation σ Δ t exceeds the preset deviation threshold σ th , then the signal is judged to be unstable and the abnormal signal needs to be identified and eliminated to ensure the accuracy of subsequent calculations. If it does not exceed the deviation threshold, the signal is stable and there is no need to eliminate the abnormal signal.

[0046] According to the processed pulse signal time interval sequence Δt i , the pulse period is calculated by weighted average method, and the weight coefficient is set as w i ,and The weighted average pulse period T wavg The calculation formula is: Given the number of ceiling fan blades n and the speed RPM pre The calculation formula is: The speed value is calculated from this, assuming I total (n) is the total pulse signal strength integral value within n blade rotation cycles, I peak (n) is the sum of the peak values ​​of the pulse signal intensity within these n cycles, RPM pre is the speed value, calculate the characteristic value F related to the period period , the formula is: Determine the period T through the function g(x) full , the formula is: Construct the speed error evaluation function E(RPM), the calculation formula is: E(RPM)=Aσ Δt +BΔT+CΔH+D|RPM-RPM nom |, calculate the corrected RPM corr The error evaluation value E(RPM corr ), if E(RPM corr ) is less than the preset error threshold E th , error threshold E th The calculation formula is: E th = k × (RPM max -RPM min ), the speed calculation result is considered accurate, and the current calculated speed is taken as the final result. If E(RPM corr )≥E th , it is necessary to recalculate to ensure high accuracy of speed calculation.

[0047] The system monitors the cumulative running time of the ceiling fan in real time run , ambient temperature change ΔT and number of consecutive measurements n meas , assuming that during this test, the ceiling fan has a cumulative running time of t run The preset cumulative running time threshold t is not reached th1 , the ambient temperature change ΔT does not exceed the set ambient temperature change threshold ΔT th , continuous measurement times n meas The number of consecutive measurements is lower than the preset threshold value n. th ,Since the calibration conditions have not been met, the system does not need to start the calibration procedure and continues to run the test process normally.

[0048] Real-time monitoring and early warning: Start the system, sample the fan speed in real time, record the light signal and the corresponding timestamp, calculate the fan speed change in real time, and set the speed fluctuation threshold T T =50r / min. When it is detected that the fluctuation amplitude of the ceiling fan speed within a unit time (set to 1 minute) exceeds the threshold, the user is prompted by a buzzer sound and a flashing LED light.

[0049] The result display and data management module displays the final calculated ceiling fan speed result on the display screen in an intuitive and clear manner, such as prominently displaying the speed value in digital form. At the same time, all relevant data involved in this measurement process, including the collected original signal data, intermediate data in the calculation process, calibration data and the final speed result, are stored in a structured format. The stored data supports a variety of convenient query methods, allowing users to view historical test data at any time. It also supports data backup and export functions to ensure data security and portability, which is convenient for further analysis or sharing data with other devices.

[0050] In summary, this embodiment demonstrates the whole process of testing the speed of a ceiling fan in a home environment. Through system preparation and parameter setting, the test system is ensured to be compatible with the ceiling fan parameters. Laser emission and signal acquisition are started to provide basic signals for subsequent calculations. Signal reception and processing effectively remove noise interference, ensure signal stability and accuracy, speed calculation and period judgment, and use scientific methods to obtain a more accurate speed value and perform reasonable verification and correction. Although the dynamic calibration is not triggered, it reflects the system's ability to continuously monitor the operating status of the ceiling fan. The final result display and data storage make it convenient for users to intuitively obtain speed information and realize effective data management.

[0051] Embodiment 2:

[0052] Commercial ceiling fan speed test

[0053] Start the ceiling fan speed test system, and the self-test module quickly carries out power-on self-test, conducts a comprehensive and detailed inspection of the key hardware components of the system, including the laser transmitter, receiver and control circuit, to ensure the normal operation of all parts of the system, and generates a detailed self-test report. The user accurately enters the number n of ceiling fan blades and the installation height information in the product setting interface. The control unit accurately adjusts the position and angle of the laser transmitter and receiver based on these input parameters, so that it can accurately align with the ceiling fan blades, making full preparations for subsequent signal acquisition and speed testing.

[0054] The signal generation and acquisition module starts the workflow according to preset parameters. The laser generator generates a stable laser pulse signal with a specific frequency f and intensity, and projects it vertically downward through the transmitting device. When the ceiling fan blades begin to rotate, the photodetector keenly receives the light signal and quickly converts it into an electrical pulse signal. The electrical pulse signal then enters the acquisition circuit and undergoes a series of processing steps including amplification, filtering, and analog-to-digital conversion to accurately convert the analog signal into a digital signal. At the same time, the start time of signal acquisition is accurately recorded, providing an accurate time reference for subsequent speed calculations.

[0055] As the ceiling fan blades continue to rotate and cut the laser beam, the laser receiver continues to receive the light signal and converts it into an electrical pulse signal. Let the amplified electrical signal be V out (t), for V out (t) is sampled, and the sampling frequency is f s , the number of sampling points is N, and the discrete signal sequence is V out [n], assuming that the coefficient of the finite impulse response digital filter is h[k], the calculation formula of the filtered signal y[n] is: The moving average method is used to smooth the filtered signal. Assuming the moving average window length is L, the smoothed signal s[n] is: Perform pulse detection on the smoothed signal s[n]. When s[n] exceeds the pulse detection threshold V th When a pulse is detected, the sampling point number n corresponding to the rising or falling edge of each pulse is recorded. i , calculate the time interval Δt between adjacent pulses i , the formula is: Calculates the average value of a time interval and standard deviation σ Δt , the formula is: If the standard deviation σ Δt Exceeding the preset deviation threshold σ th , then the signal is judged to be unstable, and the abnormal signal needs to be carefully identified and eliminated to ensure the accuracy and reliability of subsequent calculation results. If it does not exceed the deviation threshold, the signal is stable and there is no need to eliminate the abnormal signal.

[0056] According to the processed pulse signal time interval sequence Δt i , use the weighted average method to accurately calculate the pulse period, and set the weight coefficient as w i ,and The weighted average pulse period T wavg The calculation formula is: Given the number of ceiling fan blades n and the speed RPM pre The calculation formula is: The speed value is calculated from this, assuming I total (n) is the total pulse signal strength integral value within n blade rotation cycles, I peak (n) is the sum of the peak values ​​of the pulse signal intensity within these n cycles, RPM pre is the speed value, calculate the characteristic value F related to the period period , the formula is: Determine the period T through the function g(x) f ull, the formula is: Construct the speed error evaluation function E(RPM), the calculation formula is: E(RPM)=Aσ Δt +BΔT+CΔH+D|RPM-RPM nom |, calculate the corrected RPM corr The error evaluation value E(RPM corr ), E(RPM corr ) is less than the preset error threshold E th , then the speed calculation result is determined to be accurate and reliable, and the currently calculated speed is used as the final speed test result E (RPM corr )≥E th , the recalculation program is started immediately to ensure the high accuracy and reliability of the speed calculation results.

[0057] The system closely monitors the cumulative running time of the ceiling fan in real time run , ambient temperature change ΔT and number of consecutive measurements n meas The key parameter is that during this test, the ceiling fan has a cumulative running time of t run Reach the preset cumulative running time threshold t th1 Or the ambient temperature changes by more than the set ambient temperature change threshold ΔT th Or the number of consecutive measurements reaches the preset consecutive measurement threshold n th As long as any of the calibration conditions is met, the system will immediately trigger the calibration procedure. After the dynamic calibration module is started, the standard rotating device driven by the motor is precisely controlled to rotate at different preset speeds RPM. siDuring operation, the laser transmitter emits a laser pulse signal, and the laser receiver collects the signal modulated by the standard rotating device and calculates the speed error at each preset speed. The formula is: ΔRPM i =RPM si -RPM mi , calculate the speed error change rate δRPM i , the formula is: According to the speed error and speed error change rate data, the system automatically and intelligently adjusts the system parameters, so that the system can adapt to environmental changes and changes in equipment operating status, ensuring the accuracy of the test results. At the same time, the calibration data is recorded in detail to provide an important basis for subsequent system performance analysis and optimization.

[0058] After the system is started, the ceiling fan speed is sampled in real time at intervals of 100 milliseconds. After each sampling, the optical signal is converted into an electrical pulse signal, filtered, smoothed, etc., and the current RPM is calculated based on the pulse signal time interval and the number of 4 fan blades. current , set the speed fluctuation threshold T T =40r / min, the system accumulates the absolute value ∑|ΔRPM| of the difference between adjacent sampling speeds within 1 minute. When ∑|ΔRPM| exceeds the threshold, an early warning is triggered. The early warning method includes controlling the buzzer to emit an alarm sound of 10000Hz for 2 seconds, and a red pop-up window containing speed information and a change trend chart will pop up on the display screen. If the system is bound to a mobile phone, a text message notification containing abnormal speed information will be automatically sent.

[0059] The result display and data management module displays the final calculated ceiling fan speed result in a clear and intuitive graphical manner on a high-resolution display screen, such as through speed trend graphs and numerical display in various forms, so that users can understand the speed of the ceiling fan at a glance. At the same time, all relevant data generated during this measurement process, including the collected original signal data, intermediate data in the calculation process, calibration data and final speed results, are efficiently stored in a structured format. The stored data supports a variety of convenient query methods. Users can quickly retrieve historical test data according to different needs. It also has powerful data backup and export functions to ensure data security and portability, making it convenient for users to perform data analysis, generate reports or interact and share data with other devices.

[0060] In summary, this embodiment elaborates on the operational process of ceiling fan speed testing in commercial places, from careful preparation before the test, to the precise execution of laser emission and signal acquisition, and then to the rigorous operation of signal processing, speed calculation and cycle judgment. Especially in the dynamic calibration link, when the calibration conditions are met, the calibration program is triggered in time, and the system parameters are effectively adjusted to ensure the accuracy of the test results. The result display and data storage functions not only provide users with clear and intuitive speed information display, but also realize structured storage, convenient query, backup and export of data.

[0061] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A ceiling fan speed testing method, characterized in that: The specific steps of this test method are: S100, system preparation and parameter setting: start the ceiling fan speed test system, conduct a comprehensive power-on self-test on the entire system, and the user enters the ceiling fan parameters through the product setting interface. According to the input installation height information, adjust the position and angle of the laser transmitter and receiver; S200, laser emission and signal collection start: the laser transmitter emits a laser pulse signal vertically downward according to a preset frequency and intensity, and the laser receiver simultaneously starts collecting signals and records the start time; S300, signal reception and processing: After the blades rotate to cut the laser beam, the laser receiver converts the optical signal amplification circuit into an electrical pulse signal and amplifies it, and simultaneously performs filtering, denoising and smoothing on the electrical pulse signal. The signal stability is determined by statistically analyzing the time interval of the electrical pulse signal, and abnormal signals are eliminated; S400, speed calculation and cycle judgment: according to the pulse signal time interval and the known number of wind blades, the speed is calculated using an algorithm formula, the blade rotation cycle is judged by combining the algorithm formula with the speed value, and the calculation result is verified and corrected; S500, dynamic calibration: real-time monitoring of the ceiling fan's cumulative operating time, ambient temperature changes, and number of consecutive measurements. When any preset calibration conditions are met, the calibration is started, and a standard rotating device with a known speed is used to run at different speeds. The laser transmitter and receiver measure and compare the speed with the standard speed to calculate the speed error, adjust the system parameters according to the speed error, and record the calibration data; S600 real-time monitoring and early warning: Start the system, sample the ceiling fan speed in real time, record the light signal and the corresponding timestamp, calculate the ceiling fan speed change in real time, and set the speed fluctuation threshold T T , when the fluctuation range of the detected ceiling fan speed within a unit time exceeds the threshold, an early warning signal is issued to remind the user through sound, flashing lights or pop-up windows; S700, result display and data storage: the final calculated ceiling fan speed result is displayed on the display screen, and at the same time, all relevant data in this measurement process, including the collected original signal data, the intermediate data in the calculation process, the calibration data and the final speed result are stored.

2. A ceiling fan speed testing method according to claim 1, characterized in that: In the above S300, the electric pulse signal is filtered, de-noised and smoothed in the signal reception and processing, and a finite impulse response digital filter is used for filtering and de-noising. The amplified electric signal is assumed to be V out (t), for V out (t) is sampled, and the sampling frequency is f s , the number of sampling points is N, and the discrete signal sequence is v out [n], n = 0, 1, ..., N-1, the coefficient of the finite impulse response digital filter is h[k], k = 0, 1, ..., M-1, M is the filter order, and the calculation formula of the filtered signal y[n] is: The moving average method is used to smooth the electric pulse signal. Assuming the moving average window length is L, the smoothed signal s[n] is:

3. A ceiling fan speed testing method according to claim 1, characterized in that: In the above S300, during the signal reception and processing, the signal stability is determined by statistically analyzing the time interval of the electric pulse signal, and the smoothed signal s[n] is pulse detected. When s[n] exceeds the pulse detection threshold V th When a pulse is detected, the sampling point number n corresponding to the rising or falling edge of each pulse is recorded. i , calculate the time interval Δt between adjacent pulses i , the formula is: where f s is the sampling frequency, and the average value of the time interval is calculated and standard deviation σ Δt , the formula is: Where K is the number of pulses detected, and the standard deviation σ Δt Exceeding the preset deviation threshold σ th , thinking that the signal is unstable.

4. A ceiling fan speed testing method according to claim 1, characterized in that: In the above S400, the speed is calculated by weighted average in the speed calculation and period judgment, and the speed is calculated according to the processed pulse signal time interval sequence Δt i , i = 1, 2, ..., K, K is the number of pulses detected, the pulse period is calculated using the weighted average method, and the weight coefficient is set to w i , i = 1, 2, ..., K, and Weighted average pulse period T wavg The calculation formula is: Speed ​​RPM pre The calculation formula is: Where n is the number of ceiling fan blades.

5. A ceiling fan speed testing method according to claim 1, characterized in that: In the above S400, the rotation speed calculation and period determination are performed by combining the rotation speed value with the formula to determine the period of blade rotation. Assume that I total (n) is the total pulse signal strength integral value within n blade rotation cycles, I peak (n) is the sum of the peak values ​​of the pulse signal intensity within these n cycles, RPM pre is the speed value, T full To determine the blade rotation period, calculate the eigenvalue F related to the period period , the formula is: Determine the period T through the function g(x) full , the formula is: Where a, b, and c are constants obtained by fitting the experimental data of different types of ceiling fans.

6. A ceiling fan speed testing method according to claim 1, characterized in that: In the above S400, in the speed calculation and cycle judgment, the speed calculation result is verified by constructing a speed error evaluation function. Assuming that the speed error evaluation function is E(RPM), the calculation formula is: E(RPM)=Aσ Δt +BΔT+CΔH+D|RPM-RPM nom |, where σ Δt is the standard deviation of the pulse time interval, ΔT is the change in ambient temperature, ΔH is the change in ambient humidity, RPM nom is the nominal speed of the ceiling fan, A, B, C, D are weight coefficients determined by experiments, and the corrected speed RPM is calculated. corr The error evaluation value E(RPM corr ), E(RPM corr ) is less than the preset error threshold E th Assuming that the speed calculation result is accurate, RPM corr As the final speed calculation result; E (RPM corr )≥E th , then recalculate.

7. A ceiling fan speed testing method according to claim 6, characterized in that: In step S400, the error threshold E in the speed calculation and cycle judgment th Determine, set RPM max The maximum speed that this type of ceiling fan can reach, RPM nin is the minimum speed, k is the coefficient, and the error threshold E th The calculation formula is: E th = k × (RPM max -RPM min ).

8. A ceiling fan speed testing method according to claim 1, characterized in that: In S500, the calibration conditions in the dynamic calibration are: Ceiling fan cumulative running time monitoring: set to record the cumulative running time t of the ceiling fan run , ceiling fan cumulative running time threshold t th1 , when t run ≥t th1 When , the calibration is triggered; Ambient temperature change monitoring: every Δt temp Record a temperature value, calculate the difference ΔT between two adjacent temperature measurements, and set the ambient temperature change threshold ΔT th , when |ΔT|≥ΔT th When , the calibration is triggered; Continuous measurement number monitoring: record the number of continuous measurements n meas , set the continuous measurement number threshold n th , when n rneas ≥n th , triggers calibration.

9. A ceiling fan speed testing method according to claim 1, characterized in that: S500, calculation of the speed error and the speed error change rate in the dynamic calibration, with a preset speed RPM si The laser transmitter is operated to emit laser pulse signals, and the laser receiver collects the signals modulated by the standard rotating device and calculates the speed error ΔRPM at each preset speed. i , the formula is: ΔRPM i =RPM si -RPM mi , calculate the speed error change rate δRPM i , the formula is: Where ΔRPM i-1 It is the speed error at the last preset speed.

10. A ceiling fan speed test system, characterized in that: The system includes a laser transmitter module, a laser receiver module, a signal processing module, a data calculation and analysis module, a storage module, a display module and a control module; The laser transmitter module is composed of a laser diode, a driving circuit and an optical collimation component. Under the precise control of the driving circuit, the laser diode emits a laser that meets the specific frequency and intensity requirements, and the optical collimation component converts it into a parallel beam to provide a stable light source for the test; The laser receiver module includes a photodetector, a preamplifier and a signal conditioning circuit. The photodetector converts the received optical signal into a weak electrical signal, which is initially amplified by the preamplifier and then filtered and shaped by the signal conditioning circuit to remove interference. The processed electrical pulse signal is transmitted to subsequent modules and the start time is recorded at the same time. The signal processing module uses a filter to remove noise from the electrical pulse signal, uses a moving average method to smooth the signal, detects pulses, calculates the average value and standard deviation of the time intervals between adjacent pulses, determines signal stability, and removes abnormal signals; The data calculation and analysis module calculates the pulse period according to the processed pulse time interval to obtain the preliminary rotation speed, determines the blade rotation period by analyzing the pulse signal strength related data, constructs an error evaluation function to verify the rotation speed result, and evaluates and corrects the rotation speed according to environmental factors and the nominal rotation speed; The storage module: classifies and stores the original signal data, intermediate data, calibration data and final rotation speed results in the test through a solid state hard disk, and adds a timestamp and parameter identification; The display module: displays the final speed test result, speed change curve, environmental parameters and system working status information through the liquid crystal display; The control module is based on a microcontroller and coordinates the work of each module. It initializes the equipment and adjusts the parameters when the system starts, monitors the operating status during the test, starts the calibration when the calibration conditions are met, monitors the speed fluctuation and issues an early warning, and manages the storage and display modules.

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