Material testing machine controllerThrough the collaborative architecture of "hardware adaptation+closed-loop control+program programming", precise composite testing of tension, compression, and bending can be achieved, and mechanical performance testing of materials under complex working conditions can be adapted. The core implementation path is as follows:

1. Hardware modular adaptation lays the foundation for composite loading. The controller needs to be equipped with a switchable modular loading system, driven by a servo motor to drive a ball screw, and paired with a specialized fixture that can be quickly replaced. The wedge-shaped fixture used for stretching prevents sample slippage, the flat head fixture used for compression avoids stress concentration, and the bending test is equipped with two-point or three-point bending supports. When the fixture is replaced, the controller automatically recognizes and matches the corresponding testing mode. Simultaneously integrating multi-dimensional sensing components, the force sensor captures real-time load changes, the grating ruler monitors beam displacement, the extensometer accurately measures small deformations of the sample, and multiple sensor data are synchronously connected to the controller to ensure data collection integrity under composite working conditions.

2. Closed loop control algorithm to ensure multi-mode collaborative accuracy. The controller adopts a force displacement dual closed-loop control algorithm, which is the core of composite testing. During testing, the controller compares the preset load and displacement parameters with real-time feedback data from sensors and dynamically adjusts the output of the servo system. For example, during synchronous tensile bending testing, if the bending angle deviates from the set value, the controller will immediately fine tune the support position while maintaining stable tensile force to ensure that the two stresses are applied in coordination. In addition, through protocol conversion and signal denoising processing, signal interference during different action switching is reduced, and loading rate fluctuations and displacement deviations are controlled within a high-precision range.

3. Customize program programming to adapt to various composite working conditions. The controller is equipped with a programmable control system that supports preset or custom composite testing processes. The operator can set the testing logic through the upper computer, such as "stretching to the yield point before cyclic bending" and "alternating stretching under constant compressive load", and set parameters such as force threshold, displacement range, and action interval. The system is equipped with multiple sets of standard testing programs, compatible with various industry standards. The controller accurately triggers the switching of stretching, compression, and bending actions according to the program timing, and can also achieve synchronous execution of multiple actions to meet the testing needs of different materials.

4. Data synchronization processing and security linkage. In composite testing, the controller is connected to a high-speed data acquisition card to synchronously record force, displacement, strain and other data at high frequencies, generating multidimensional mechanical curves for analyzing the failure law of materials under composite stress. At the same time, it is equipped with a safety protection mechanism. In case of unexpected situations such as load exceeding the range or sample fracture, the controller immediately cuts off the loading command and links the crossbeam emergency stop to avoid equipment damage. After the test is completed, the data will be automatically integrated and a comprehensive report containing mechanical indicators for each stage will be output, providing a complete basis for material performance evaluation.