1. Multi axis loading mechanism design

The core of the tensile and torsional fatigue testing machine lies in its precise multi axis loading system:

Servo drive system: using high response linear motor (axial) and torque motor (circumferential) to achieve wideband loading from 0.001Hz-100Hz.

Dynamic coupling mechanism: The cross universal joint and hollow shaft design solve the interference of tension torsion motion, ensuring an angle synchronization accuracy of ± 0.5 °.

Load feedback control: Based on PID+feedforward algorithm, a 21 bit high-resolution encoder monitors displacement/rotation angle in real time, with load fluctuation<± 1% FS.

2. Technological breakthroughs in key components

Hydraulic floating fixture: 6-degree-of-freedom self-adjusting mechanism, eliminating eccentric loads (eccentricity<0.05mm)

Low temperature environmental chamber: liquid nitrogen jet refrigeration combined with infrared temperature measurement, achieving temperature control of -180 ℃~350 ℃ (gradient ± 1 ℃)

Non contact extensometer: Laser Doppler velocimeter (LDV) measures strain with a resolution of 0.1 μ m.

3. Data collection and analysis methods

Multi channel synchronous acquisition: 24 bit ADC synchronously records load/displacement/temperature signals at a sampling rate of 1MHz.

Fatigue damage model:

Cumulative damage calculation based on Miner's criterion

Identification of multi axis fatigue hazardous sections using critical plane method

△ J integral method for evaluating the driving force of crack propagation

AI assisted diagnosis: LSTM neural network predicts remaining lifespan (error<5%)

4. Typical application scenarios

Aviation blade testing: simulating centrifugal force+aerodynamic torque composite load (R=-1~0.5)

Vascular stent evaluation: biomechanical simulation of axial pulsation and circumferential torsion

Research on Nuclear Welding Materials: Corrosion Fatigue Test in High Temperature and High Pressure Water Environment

5. Technological development trends

Digital Twin System: Real time Simulation and Physical Experiment Data Fusion

Microscale testing: integrating MEMS sensors to achieve micrometer level sample characterization

Intelligent shutdown strategy: adaptive test termination based on acoustic emission signals

This device provides a precise and reliable testing platform for the study of multi axis fatigue performance of materials through innovative electromechanical coupling design and advanced data analysis methods, and has become a tool for the research and development of aviation, medical and other equipment.