CN102864537A - Realization method of programmable controller integrating yarn cleaning and yarn breaking detection - Google Patents

Abstract

The invention relates to a method for implementing a programmable controller integrating yarn clearing and yarn breakage detection. The controller includes a CPU control module, a communication module, a sensor module, an input module, a motor drive module, an output module and a power supply module. The sensor module uses a lock-in amplifier to extract the jitter signal and diameter signal of the yarn; the CPU control module is developed using a ladder diagram, and the analog signal of the yarn is converted into a digital signal through the AD sampling circuit, and the digital signal of the yarn is analyzed by the embedded intelligent detection algorithm. The signal is analyzed in the time domain and quasi-frequency domain, and the control output module and the motor drive module execute corresponding commands; the transmission of textile parameters is realized through a high-reliability communication bus. Compared with the traditional detection head, the invention simplifies the system structure of spinning control, reduces the cost and improves the stability of the system.

Description

A Programmable Controller Realization Method Integrating Yarn Clearing and Yarn Break Detection

technical field

The invention belongs to the technical field of control, and in particular relates to a method for implementing a programmable controller integrating yarn clearing and yarn breakage detection.

Background technique

During the development of the textile industry, various advanced detection technologies have been widely used, especially photoelectric detection technology. In many cases in the textile process, it is necessary to detect the yarn in motion, such as detecting yarn breakage, weft detection, and identifying coarse details. The softness of the yarn makes it vibrate at a certain frequency during the movement. When the light field is uneven, the position change caused by the jitter will change the intensity of the light signal received by the sensor. According to the motion characteristic of the yarn, the moving yarn and the static yarn (or no yarn) can be effectively distinguished. On the contrary, if the yarn is in a relatively uniform light field, the intensity of the light signal received by the sensor will reflect the diameter information of the yarn, so as to identify the coarse and fine details of the yarn.

In traditional yarn clearing and yarn break detection methods, the follow-up circuit generally detects, amplifies or rectifies the signal, and then compares and amplifies the output. Among them, the identification circuit is usually realized by using an analog circuit. The disadvantage of the analog yarn clearing circuit is that the aging of the device can easily cause changes in parameters, resulting in unstable phenomena such as mis-cutting, missed cutting, and random cutting, which is time-consuming and labor-intensive, and affects the production efficiency of the factory. In terms of the identification of yarn defects, the mathematical models based on which various electronic yarn clearers identify yarn defects are relatively fixed. Compared with the "intelligent recognition" ability of craftsmen to judge yarn defects with naked eyes The gap: on the one hand, the recognition efficiency is not high enough, and on the other hand, the yarn clearing curve of the yarn defect cannot be greatly changed.

In general, yarn break detection uses a non-uniform light field, while yarn clearing detection uses a relatively uniform light field. This is because the traditional analog circuit detection only considers the instantaneous change of the amplitude to identify the yarn signal. But the jitter characteristics of the yarn are not analyzed in the frequency domain. Therefore, it is difficult for the traditional analog discrimination circuit to carry out integrated control of yarn clearing and yarn breakage detection.

At present, the control system of the air spinning machine is based on the original yarn breakage detection device. After adding an electronic yarn clearer, it not only makes the whole system redundant and complicated, but also greatly increases the cost.

Contents of the invention

The purpose of the present invention is to provide a programmable controller implementation method that integrates yarn clearing and yarn breakage detection to address the shortcomings of the prior art.

The technical solution adopted by the present invention to solve technical problems:

A method for implementing a programmable controller that integrates yarn clearing and yarn breakage detection. The controller has a three-in-one function: yarn clearing identification, yarn breakage detection, and control drive; the controller includes a sensor module and a CPU control module. , input module, motor drive module, output module, communication module, power supply module, described CPU control module is connected with sensing module, input module, motor drive module, output module, communication module, power supply module respectively; The controller The implementation method includes the following steps:

Step 1. Yarn signal extraction: the yarn jitter and diameter signals are extracted by the sensor module based on the lock-in amplifier, and converted into related analog signals;

Step 2. Yarn signal analysis: the programmable CPU control module converts the analog signal in step 1 into a digital signal through the AD sampling circuit, and performs time domain and quasi-frequency domain analysis, and judges the yarn operation by an intelligent detection algorithm Status and yarn defect identification;

Step 3. Input and output signal control: According to the information of the input module and the communication module and the analysis result of the yarn signal in step 2, control the motor drive module and the output module to execute corresponding control commands.

The sensing module in the step 1 is based on lock-in amplification technology, and its yarn clearing identification and broken yarn detection share a sensing device, as follows:

(A) The carrier signal required for modulation is provided by the signal generating circuit, and the transmitter is signal-modulated;

(B) After the transmission signal modulated in step (A) passes through the yarn, the diameter signal and the related jitter signal of the yarn are obtained by the receiver;

(C) carry out frequency-selective amplification processing to the signal that the receiver in step (B) obtains by frequency-selective amplifier, as the signal to be measured of lock-in amplifier circuit;

(D) phase-shifting the carrier signal in the step (A) by the phase-shifting circuit, as the reference signal of the phase-locked amplifier circuit;

(E) carry out lock-in amplification processing to the signal to be measured in the step (C) and the reference signal in the step (D) by the lock-in amplifier circuit;

(F) Filtering the signal output by the lock-in amplification in step (E) by the filter circuit to obtain the relevant analog signal.

The programmable CPU control module in the step 2 is programmed using the ladder diagram of the embedded intelligent detection algorithm, and has the function of inputting the I/O port, as follows:

The CPU control module adopts a three-layer architecture: BootLoader, engine, and ladder diagram;

BootLoader is responsible for hardware port initialization and loading of engine and ladder diagram;

The engine is responsible for implementing board-level support and providing a calling interface for the ladder diagram;

The ladder diagram is the realization of the intelligent detection algorithm and related logic actions designed by the user.

Beneficial effects of the present invention:

The invention adopts a microprocessor, has the characteristics of low power consumption, high performance and high stability, and can realize fast signal processing.

The sensor module based on lock-in amplification technology can effectively suppress noise signals and improve the noise-to-noise ratio. the

Realize a detection head with a microcontroller that integrates yarn breaking and yarn clearing, and can control electromagnets and motors to perform textile actions nearby, greatly simplifying the architecture of the textile controller and reducing costs.

The CPU controller is programmed with an industrial graphic programming language, which changes the traditional PLC concept, facilitates the maintenance and upgrade of the controller, and improves the stability of the system.

Description of drawings

Fig. 1 is the realization structural block diagram based on DSP core controller;

Figure 2 is a block diagram of the internal structure of the sensing module;

Fig. 3 is a schematic diagram of a program layered architecture based on the DSP kernel;

Figure 4 is a schematic diagram of the communication network of the yarn detection head;

Figure 5 is the main program block diagram of the DSP controller.

Detailed ways

The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings: the present embodiment is implemented on the premise of the programmable (PLC) integrated yarn clearing and thread breaking integrated control method of the present invention, and detailed details are provided below Embodiment and specific operation process, but protection scope of the present invention is not limited to following examples.

As shown in Figure 1, this embodiment includes a sensing module, a DSP control module (CPU control module), an input module, a motor drive module, an electromagnet drive module (output module), a CAN communication module, and a power supply module. The DSP control module is respectively connected with the sensor module, the input module, the motor drive module, the electromagnet drive module, the CAN communication module and the power supply module.

The DSP control module is the core part of the whole yarn detection head, including the minimum system of the DSP controller, including AD sampling circuit, reset circuit, JTAG circuit, clock circuit, power-down protection circuit and DSP core controller.

The DSP controller can obtain the yarn signal through high-speed A/D conversion (the yarn frequency is generally lower than 1kHz, and the sampling frequency is 10kHz), analyze the sampled data in time domain and quasi-frequency domain, extract relevant characteristic values, and use intelligent Algorithms (BP neural network, EMD and SVM, etc.) to judge the matching of yarn running signals and yarn defect categories; output PWM pulses with adjustable duty ratio and frequency at any time, isolated by TLP116 high-speed optocoupler, to control various types of motor textiles Yarn; output I/O port signal, isolated by TLP112 optocoupler, control the threading electromagnet, arm electromagnet, cutter electromagnet to execute yarn splicing or cutting commands; communicate with upper PLC or PC through CAN bus interface It communicates with the machine to complete the transmission of textile parameters or online programming of the yarn detection head. The power supply module, electromagnet drive module and motor drive module adopt mature technology.

As shown in FIG. 2 , it is a schematic diagram of the internal structure of the sensing module. The sensing module is a high-speed signal processing circuit with a lock-in amplifier as the core, including a signal generating circuit, a sensing circuit, a frequency-selective amplifier circuit, a phase-shifting circuit, a lock-in amplifier circuit, and a filter circuit. The signal generation circuit provides the carrier signal required for modulation by the signal transmitter. In this embodiment, the sinusoidal signal generation circuit generates f=30KHz, Vp-p=500mV sinusoidal carrier signal, and modulates and transmits the infrared emission tube; the sensing circuit is used for Extract the diameter signal of the yarn and the related jitter signal, specifically gather the modulated infrared emission light through the optical path piece 1, obtain the diameter optical signal through the yarn, and then pass through the optical path piece 2, and the infrared signal detector will carry the yarn The optical signal of the diameter is converted into an electrical signal and carries relevant yarn jitter information; the frequency-selective amplifier circuit is used to filter out high-frequency noise signals and provide a relatively pure yarn diameter signal for the back-end, specifically the sensor circuit. The electrical signal is amplified by the low-noise frequency-selective amplifier at the front and used as the signal to be tested by the lock-in amplifier; the phase shift circuit realizes the phase shift of the modulation signal from 0 to 360 degrees, so that the reference signal input to the phase-locked module and the signal to be tested Inter-synchronization, specifically, the sinusoidal carrier signal is passed through the phase-shifting circuit as the reference signal of the lock-in amplifier; the lock-in amplifier circuit uses the frequency of the reference signal to correlate with the frequency of the input signal, and is not related to the noise signal, and extracts the yarn diameter from the strong noise signal to improve the measurement accuracy. Specifically, the lock-in amplifier multiplies and integrates the input signal to be tested with the same frequency and phase and the reference signal, that is, correlation detection. The useful yarn diameter signal is amplified, while the noise and non-identical The relevant signal is suppressed, thereby greatly improving the signal-to-noise ratio; the filter circuit is used to filter out the DC component in the front-end modulation signal, and obtain an electrical signal proportional to the yarn diameter, specifically the output of the lock-in amplifier circuit After the signal passes through the filter circuit, the analog signal related to the yarn jitter and its diameter is obtained.

As shown in Figure 3, the DSP controller in this embodiment adopts the ladder diagram programming technology based on generalized PLC, and the core of its software adopts a three-layer architecture mode: BootLoader, engine, and ladder diagram. Among them, BootLoader is responsible for loading the engine and ladder diagram, and initializing the electromagnet and motor drive ports; the engine is responsible for implementing board-level support, task scheduling, and providing a calling interface for the ladder diagram; the ladder diagram is responsible for designing corresponding algorithms and action processes for practical applications . Through the ladder diagram programming, the consistency of the logic control program is guaranteed, making it possible to customize a special yarn clearing algorithm for different yarn clearing characteristic curves, and at the same time provide a quick way for users to develop secondary.

As shown in Fig. 4, the communication between this embodiment and the outside adopts the CAN bus. Each detection head communicates with the upper PLC through the CAN bus to form a network for the entire network. The baud rate is 9600bps and the Mod-bus communication protocol is adopted. When working, the upper PLC sends the textile parameters set by the human-machine interface to each detection head through the CAN bus in the form of a broadcast frame, and the detection head controls the electromagnet and the motor to execute the textile command according to the obtained parameters, and detects the yarn defects. Statistical analysis is carried out on the category of yarn defects, which is fed back to the upper PLC through the CAN bus, and the user can guide the production according to the statistical analysis of yarn defects on the man-machine interface.

The main program flow of the DSP controller, the core component of the integrated detection head, is shown in Figure 5. The main program adopts cyclic setting, comparison, and discrimination methods to continuously sample and obtain yarn signal data to judge yarn status information; A/D sampling and digital filtering are completed in the interrupt subroutine. After the main program initializes the parameters, it judges whether the communication flag is set. If the communication is set, the textile parameters are modified according to the corresponding data; according to the yarn data obtained by sampling, it is judged whether there is yarn in the detection slot. Compensate for hairiness and dust, and self-adaptively correct the parameters at the same time. If there is, judge the running state of the yarn; The average reference diameter of the thread is used for learning; the state of the yarn is judged according to the newly sampled data. If the yarn breaks abnormally, it will enter the yarn breakage process. If the yarn is in the running state, the sampled data will be time-domain And similar frequency domain analysis, and then the corresponding intelligent algorithm is used to match the yarn defect; if there is a yarn defect, the yarn breakage will be processed, if there is no yarn defect, the communication data will be processed, and the new sampling data will be waited.

Claims (3)

1. one kind collects the controller implementation method that clearing and broken yarn detect able to programmeization of one, and it is characterized in that: controller has Trinitarian function: clearing is differentiated, broken yarn detects, control drives; This controller comprises sensing module, CPU control module, input module, motor drive module, output module, communication module, power module, and described CPU control module is joined with sensing module, input module, motor drive module, output module, communication module, power module respectively; This controller implementation method may further comprise the steps:

Step 1. yarn signal extracts: extract yarn shake and diameter signal by the sensing module based on lock-in amplifier, and be converted to relevant analog signal;

The analysis of step 2. yarn signal: the CPU control module by able to programmeization is data signal by the AD sample circuit with the analog signal conversion in the step 1, and carries out time domain and class frequency-domain analysis, judges yarn running status and the discriminating of yarn defect by the Intelligent Measurement algorithm;

The control of step 3. input/output signal: according to the information of input module, communication module and the yarn signal analysis result in the step 2, control motor drive module and output module are carried out corresponding control command.

2. controller implementation method as claimed in claim 1, it is characterized in that: sensing module is based on phase lock amplifying technology in the described step 1, and its clearing differentiates to detect with broken yarn and share a sensing device, and is specific as follows:

(A) provide modulation required carrier signal by signal generating circuit, and transmitter is carried out the signal modulation;

That (B) modulates in the step (A) transmits through behind the yarn, is obtained diameter signal and the associated jitter signal of yarn by receiver;

(C) by frequency-selective amplifier the resulting signal of receiver in the step (B) is carried out frequency-selecting and amplify processing, as the measured signal of phase-locked amplifying circuit;

(D) by phase-shift circuit the carrier signal in the step (A) is carried out phase shift, as the reference signal of phase-locked amplifying circuit;

(E) by phase-locked amplifying circuit the reference signal in the measured signal in the step (C) and the step (D) being carried out phase-locked amplification processes;

(F) signal of by filter circuit phase-locked amplification in the step (E) being exported carries out filtering and processes the analog signal that obtains being correlated with.

3. controller implementation method as claimed in claim 1, it is characterized in that: the CPU control module of able to programmeization adopts the ladder diagram of embedded Intelligent Measurement algorithm to programme in the described step 2, has and can input I/O mouth function, and is specific as follows:

The CPU control module adopts the three-tier architecture mode: BootLoader, engine, ladder diagram;

Described BootLoader is responsible for hardware port, and just making and engine, ladder diagram load;

Described engine is responsible for realizing the support of plate level, for ladder diagram provides calling interface;

The realization of the Intelligent Measurement algorithm that described ladder diagram designs for the user and interrelated logic action.

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