High-Speed Strain Gauge Acquisition System for Split Hopkinson Pressure Bar Systems
Challenge :
A high-speed acquisition system is required to read strain value change patterns in the Split Hopkinson Pressure Bar (SHPB) system
Solution:Designing a LabVIEW-based Split-Hopkinson Pressure Bar (SHPB) testing acquisition system using a Strain Gauge Amplifier and Oscilloscope for high-speed acquisition system solutions.
The Split-Hopkinson Pressure Bar (SHPB) is one of the commonly used methods to determine the dynamic characteristics of a material. SHPB testing is conducted by observing the strain change pattern on the Incident Bar and Transmission Bar.
Figure 1. Simple illustration of SHPB testing
The striker bar will be launched at high speed by the gas launcher. The incident wave formed during the collision process will be transmitted to the specimen. The incident wave passing through the incident bar will be measured using a strain gauge. The incident wave hitting the specimen will partly become a transmitted wave and partly a reflected wave.
The transmitted wave will be transmitted to the transmission bar and the reflected wave will be retransmitted to the incident bar, and both will be measured using strain gauges on each bar.
The testing process on this device occurs very quickly, requiring a very fast acquisition system (above 100,000 samples/s) in order to obtain accurate data on the dynamic changes in strain wave values.
The strain gauge attached to the striker bar and transmission bar is connected to a strain gauge amplifier. The amplifier contains a Wheatstone bridge circuit used to read changes in resistance from the strain gauge, as well as an amplifier circuit. An oscilloscope reads the analog signal from the strain gauge amplifier, and the reading data is sent to a computer.
With the ease of LabVIEW to interact with various devices, the developed system can also be used to adjust settings on the oscilloscope and strain gauge amplifier through GPIB and Serial communication.
If you have any questions about this application or general solutions related to this topic or other topics, please contact us at sales@haliatech.com or support@haliatech.com.
Author Information :
Reza Ar Raffi Birahmatika
M. Dani Anwar
Bekasi Jawa Barat Indonesia
(021) 2217-8880
