I. Overview
This machine is primarily used for the fatigue performance testing and performance requirements of the neck of handle-type femoral components according to YY/T0809.6-2018, and for tensile and compressive fatigue tests of partial and total hip joint prosthetics as per ISO 7206-6:2013.
Also suitable for fatigue life testing of shell implants such as locked intramedullary nails, handle femoral components, torque-acting handle femoral components, metal angle fixators, etc. Additionally, it can be used for fatigue mechanical property testing of artificial structural components and static mechanical property testing of various medical devices, other types of metal, non-metallic materials, structural components, and parts.
This machine is centered around electronic servo control technology, utilizing contemporary direct-acting servo technology internationally. It features no need for hydraulic power source, no cooling equipment, and energy-saving capabilities, making it a technical product in the field of small-tonnage fatigue testing.
II. System Description
1. Main Unit:
The main unit features a frame-type structure, with the servo linear actuator mounted internally within the main unit frame.
Manual cam mechanism for quick clamping and positioning of samples.
The main unit features a double-column frame structure, with the outer surface treated with hard chrome plating, ensuring both aesthetic appeal and corrosion resistance.
Load sensors are mounted on the lower face of the actuator to measure test loads.
The mainframe workbench is designed with试样clamping, beam movement, and emergency stop buttons in front, facilitating the operator's ease of use.
2. All-Digital Single-Channel Servo Controller:
2.1 Features
Control Channels: 1; Full Digital Universal Signal Conditioning Unit: Three measurement channels, closed-loop control loops for test force, displacement, and deformation. Features undisturbed smooth switching between control modes.
Closed-loop control data refresh rate is 2kHz.
Controller A/D, D/A resolution is 16 bits.
Signal Frequency Range: 0.001 Hz to 5 kHz
Signal Generator Waveforms: Sine wave, triangular wave, programmed wave, etc.
The controller features limit parameter settings and comprehensive protection functions.
In addition to overcurrent protection (110%) and secondary overcurrent protection, it also features adjustable dynamic load upper and lower limit protection, static load upper and lower limit protection, frequency protection, etc.
2.2 Servo Dynamic Tester (System) Control Software:
System Management Software: This software serves as the foundation for the entire fully digital servo controller's operation, primarily managing the hardware resources of the control system, defining sensors, adjusting digital control parameters, setting protection, displaying the current control mode, hydraulic and function generator status, and sensor calibration. It also provides dual-trace digital oscilloscope and function generator software: This software is mainly used for constant amplitude dynamic tests, such as constant amplitude fatigue tests. The function generator software automatically tracks and corrects the peak and valley values of the controlled quantities (e.g., load) to ensure that during the entire test process, the typical dynamic error of each peak is ±1%FS. During the test, operators can dynamically change the peak, valley, and frequency, and can also perform manual or automatic signal hold. If the automatic signal hold cycle interval is set, the software will automatically maintain the signal at the set level each time the cycle count increases by one cycle interval, facilitating the measurement of certain test data (such as visually measured crack length). The optional waveforms include sine wave, triangle wave, ramp wave, sawtooth wave, composite wave, and composite ramp wave tests. Upon completion of the test, the software saves some important data, such as test load, frequency, cycle count, and test time. This software can also conduct simple static tests. Multi-functional Test Software: This software is a flexible and feature-rich test software that allows users to design special test methods without programming. The software presents the various control functions, data acquisition functions, and some auxiliary functions of the servo controller in the form of icons on a panel. Users can drag and drop these function icons into the test definition panel and arrange them according to their needs, allowing tests to be conducted according to the user-defined test method. The software can be used for random spectrum tests.
The machine's measurement and control system utilizes a computer bus design. The entire system features zeroing, calibration, continuous full-range measurement, and stepless speed control functions.
The system allows for rate control of test force and can maintain the test force.
Can perform deformation rate control and maintain deformation.
Positioning with rate control and hold functionality available.
During the testing process, various control rates and methods can be smoothly switched.
The machine can perform low-frequency cyclic and fatigue tests, featuring a combination of triangular, sine, square waves, and random waveforms. The testing process can be automated with programmed operation.
Complete machine protection, oil source failure alarm and automatic protection functions.
Features monitoring of the testing process, and fault self-diagnosis function for the measurement and control system.
Accurate measurement, comprehensive features, high reliability, easy operation, and convenient usage.
The control system features an oscilloscope detection interface.
A user-friendly human-machine interface that facilitates monitoring and management of system tests, as well as processing of test data.
Operators can complete the control and management of the test with just a mouse (keyboard-assisted input of parameters).
The software can perform various waveform tests on components.
Available for force control, displacement or strain control, and can be randomly and smoothly switched.
Multiple curves, data windows, and test status windows can be displayed simultaneously on the computer screen, with output and printing capabilities.
During the program test, intervention in control methods and adjustment of control parameters can be made at any time.
Comprehensive software self-check function, indicating the location of any faults, eliminating the need for on-site repairs by the manufacturer. Simply replace the corresponding function card within the computer.
Achieves network communication.
Section 3: Key Technical Specifications:
Actuator (Parker, USA)
Actuator Stroke: 150mm
Actuator structure type: Electric Servo
Single servo cylinder dynamic test force: 5KN
Frequency: 20 Hz
2. Test Force Measurement System
Utilize load sensors for inertia-free measurement of test forces.
Test Force Display: The computer screen shows the direct reading in real time.
3. Deformation Measurement System
Measure deformation within the specimen gauge length using a displacement sensor.
Deformation Display: The computer screen displays the real-time direct readings.
4. Displacement Measurement System
The value is displayed on the computer screen.
Travel Range: 150mm (determined by actuator stroke)
Displacement Measurement Resolution: 2μm
Measurement Error: ±2μm
Speed Control
Note: The technical parameters of this system fully comply with the relevant national standards.
Servo Motor (Parker USA), Servo Drive (Parker USA), Rated Voltage: 220V, Working Frequency: 50Hz; Servo Linear Actuator (Parker USA)
