Rock-soil triaxial testing machine control system

Abstract

The utility model discloses a control system of a rock-soil triaxial testing machine, and belongs to the technical field of testing machine control. Comprising a static triaxial tester host, a confining pressure cylinder, a triaxial apparatus, a servo hydraulic source and an electric control part, the electric control part comprises a PC, an acquisition driving module, a true triaxial data acquisition module and a power supply, and the true triaxial data acquisition module comprises a rock-soil triaxial servo device and a data acquisition sensor used for acquiring required data of the rock-soil triaxial servo device. The acquisition driving module comprises an analog signal amplification filter circuit, a multi-path A / D conversion circuit and a USB interface circuit which are electrically connected in sequence, the USB interface circuit is electrically connected with the PC, the PC is electrically connected with a motor driver of servo equipment of the rock-soil triaxial testing machine, and the multi-path A / D conversion circuit is connected with the data acquisition sensor. The multi-cylinder synchronous and asynchronous loading control system is simple in structure and accurate and rapid in control, and accurate control over multi-cylinder synchronous and asynchronous loading can be completed through the PC, the acquisition driving module and the true triaxial data acquisition module.

Description

Technical Field

[0001] The utility model relates to the technical field of testing machine control, in particular to a rock and soil triaxial testing machine control system. Background Art

[0002] With the continuous improvement of geotechnical engineering theories and methods and the rapid development of automatic control science, the combination of automatic control technology and geotechnical engineering test equipment has realized automatic control on some geotechnical test equipment with single functions and simple structures. For example, in consolidation tests, multiple consolidation instruments can work simultaneously, and the upper computer can automatically collect settlement data and process them; in dynamic triaxial experiments, the test loading frequency is high, which cannot be achieved by manual reading alone. Now, with various mature sensors and the upper computer automatic data acquisition system, automatic control has been fully realized. Therefore, the automatic control of the physical and mechanical properties of various rock and soil bodies has been basically realized by targeting geotechnical test equipment with single functions and simple structures. However, there is currently a lack of high-quality and high-precision automatic integrated control systems for geotechnical test equipment with diverse functions, complex structures, and the ability to simulate multiple stress paths. Utility Model Content

[0003] The utility model aims to provide a control system for a geotechnical triaxial testing machine, thereby solving the problems raised in the above-mentioned background technology.

[0004] The technical solution adopted by the utility model is as follows:

[0005] A geotechnical triaxial testing machine control system comprises a static triaxial testing machine mainframe 1, a confining pressure cylinder 2, a triaxial machine 3, a servo hydraulic source 4 and an electronic control unit 5, wherein the electronic control unit 5 comprises a PC, an acquisition drive module, a true triaxial data acquisition module and a power supply, wherein the true triaxial data acquisition module comprises a geotechnical triaxial servo device and a data acquisition sensor for acquiring required geotechnical triaxial servo device data, wherein the acquisition drive module comprises an analog signal amplification and filtering circuit, a multi-channel A / D conversion circuit and a USB interface circuit which are electrically connected in sequence, wherein the USB interface circuit is electrically connected to the PC, wherein the PC is electrically connected to a motor driver of the geotechnical triaxial testing machine servo device, and wherein the multi-channel A / D conversion circuit is connected to the data acquisition sensor.

[0006] The data acquisition sensor comprises a load sensor and a hydraulic pressure sensor installed on the hydraulic cylinder, a displacement sensor for detecting displacement of the sample in all directions, and a pressure sensor for pore water pressure of the base.

[0007] The servo equipment of the geotechnical triaxial testing machine comprises a stepping motor, a hydraulic cylinder and a servo valve connected to the hydraulic cylinder.

[0008] The analog signal amplifying and filtering circuit is composed of AD620AR and TL072CD.

[0009] The USB interface circuit is composed of a USB to serial port chip FT232BL.

[0010] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0011] The utility model has a simple structure and the control is precise and rapid. Through the arranged PC, acquisition drive module and true three-axis data acquisition module, the output analog signal can be fed back through the servo valve drive circuit, and the servo valve is driven to adjust the flow or pressure of the pressure oil supplied to the hydraulic cylinder, so that the hydraulic cylinder runs in the direction of reaching a given target value, thereby completing the precise control of multi-cylinder synchronous and asynchronous loading. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a principle block diagram of the utility model;

[0013] Figure 2 It is a schematic diagram of the structure of the utility model;

[0014] Figure 3 This is the schematic diagram of the analog signal amplification and filtering circuit of the utility model;

[0015] In the figure: main machine of static triaxial testing machine 1; confining pressure cylinder 2; triaxial machine 3; servo hydraulic source 4; electronic control unit 5. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Generally, the components of the embodiment of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0017] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1

[0019] like Figure 1-3The present embodiment provides a geotechnical triaxial testing machine control system, including a static triaxial testing machine mainframe 1, a confining pressure cylinder 2, a triaxial machine 3, a servo hydraulic source 4 and an electronic control unit 5, wherein the electronic control unit 5 includes a PC, an acquisition drive module, a true triaxial data acquisition module and a power supply, wherein the true triaxial data acquisition module includes a geotechnical triaxial servo device and a data acquisition sensor for acquiring required geotechnical triaxial servo device data, wherein the acquisition drive module includes an analog signal amplifying and filtering circuit ( Figure 1 The analog signal amplifying board in the test machine), a multi-channel A / D conversion circuit and a USB interface circuit, wherein the USB interface circuit is electrically connected to a PC, the PC is electrically connected to a motor driver of a servo device of a geotechnical triaxial testing machine, and the multi-channel A / D conversion circuit is connected to a data acquisition sensor.

[0020] The data acquisition sensor comprises a load sensor and a hydraulic pressure sensor installed on the hydraulic cylinder, a displacement sensor for detecting displacement of the sample in all directions, and a pressure sensor for pore water pressure of the base.

[0021] The geotechnical triaxial testing machine servo equipment comprises a stepping motor, a hydraulic cylinder and a servo valve connected to the hydraulic cylinder.

[0022] The analog signal amplifying and filtering circuit is composed of AD620AR and TL072CD.

[0023] The USB interface circuit is composed of a USB to serial port chip FT232BL.

[0024] The use principle of the utility model is that the PC is used to set the test parameters and send the test parameters to the acquisition drive module, and the experimental results fed back by the acquisition drive module are saved; the geotechnical data acquisition module is used to collect test data, including geotechnical three-axis servo equipment and data acquisition sensors, and the data acquisition sensors are used to collect the required geotechnical three-axis servo equipment data. The acquisition drive module is used to transmit the test parameters to the true three-axis servo equipment data, control its work, and perform data acquisition. At the same time, the data signals collected by the data acquisition sensor are also processed and transmitted to the PC.

[0025] The data acquisition module of the geotechnical triaxial testing machine is used to collect test data, including the geotechnical triaxial testing machine servo equipment and the data acquisition sensor. The data acquisition sensor is used to collect the required geotechnical triaxial servo equipment data; the acquisition drive module includes a multi-channel A / D conversion circuit, an analog signal amplification and filtering circuit, and the single-chip microcomputer is also connected to the drive device of the true three-axis servo equipment and the PC, and the multi-channel A / D conversion circuit and data acquisition.

[0026] The analog signal output by the sensor in the utility model is amplified and filtered by the analog signal amplification and filtering circuit composed of AD620AR and TL072CD, and then A / D acquisition is performed through the multi-channel A / D conversion circuit; the USB interface circuit is designed and implemented by the USB to serial port chip FT232BL to realize communication with the PC. The acquisition drive module mainly realizes the signal acquisition of the analog quantity input by the pressure sensor, displacement sensor, load sensor, and hydraulic sensor, and realizes the drive and acquisition cycle of 5ms frequency according to the motor and drive module.

[0027] The utility model controls all groups of hydraulic cylinders to complete work as required by giving target values ​​and control modes through a computer software program. The real-time signals measured by the sensors on all hydraulic cylinders are amplified by the corresponding sensor amplification and conditioning circuits, and synchronously collect up to 5 channels and 10 roads of various sensor amplification signals through a PCI9111-A / D digital-to-analog conversion acquisition card from Taiwan, China, and convert the collected feedback analog signals into digital signals. The given value and the feedback value are compared in real time through the closed-loop calculation of the computer, and the difference is calculated through the closed-loop PID control algorithm of the software program, and then the calculated difference digital signal is converted into an analog signal for output through a PCI 6208V-D / A analog-to-digital conversion card from Taiwan, China. The output analog signal is fed back through the servo valve drive circuit, driving the servo valve to adjust the flow or pressure of the pressure oil supplied to the hydraulic cylinder, so that the hydraulic cylinder runs in the direction of reaching the given target value, thereby completing the precise control of multi-cylinder synchronous and asynchronous loading.

Claims

1. A geotechnical triaxial testing machine control system, comprising a static triaxial testing machine mainframe (1), a confining pressure cylinder (2), a triaxial machine (3), a servo hydraulic source (4) and an electronic control unit (5), characterized in that: The electric control unit (5) comprises a PC, an acquisition drive module, a true three-axis data acquisition module and a power supply, the true three-axis data acquisition module comprises a geotechnical three-axis servo device and a data acquisition sensor for acquiring required geotechnical three-axis servo device data, the acquisition drive module comprises an analog signal amplification and filtering circuit, a multi-channel A / D conversion circuit and a USB interface circuit which are electrically connected in sequence, the USB interface circuit is electrically connected to the PC, the PC is electrically connected to a motor driver of the geotechnical three-axis testing machine servo device, and the multi-channel A / D conversion circuit is connected to the data acquisition sensor.

2. A geotechnical triaxial testing machine control system according to claim 1, characterized in that: The data acquisition sensor comprises a load sensor and a hydraulic pressure sensor installed on the hydraulic cylinder, a displacement sensor for detecting displacement of the sample in all directions, and a pressure sensor for pore water pressure of the base.

3. A geotechnical triaxial testing machine control system according to claim 1, characterized in that: The geotechnical triaxial testing machine servo equipment comprises a stepping motor, a hydraulic cylinder and a servo valve connected to the hydraulic cylinder.

4. The control system of a geotechnical triaxial testing machine according to claim 1, characterized in that: The analog signal amplifying and filtering circuit is composed of AD620AR and TL072CD.

5. The control system of a geotechnical triaxial testing machine according to claim 1, characterized in that: The USB interface circuit is composed of a USB to serial port chip FT232BL.

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