Development of Digital Measurement System for Analog Universal Testing Machine

Today, Older Analog universal testing machines are still in use. Often, the equipment remains functional decades after initial purchase, thereby returning the initial investment back to the owner. However, older machines should be upgraded to benefit from newer innovations and capabilities. The replacement costs for the older mechanical testing machines can be in the tens and hundreds of thousands of dollars. By retrofitting an older machine, the owner will gain a clear cost benefit over the purchase of a new system. The reason for this is, since the most expensive and durable part of a new system is the load frame, keeping that old load frame in place and merely adding digital controllers and windows-based software, one expands the functionality with minimum investment. Computerized universal testing machines available are so advanced with the capability of analysing and displaying multiple material properties on system. But these systems are expensive and with complex designs because of using different advance electronic equipment to computerize the system. So, by developing existing universal testing machine with low-cost equipment can resolve the problem of taking manual readings of different material properties testing. This development is been done to provide developed low-cost universal testing machine which can measure different material properties by performing material tests giving relation between stress and strain data generated through Processing 3 software and pressure-displacement sensors which are interfaced by Arduino microcontroller. Data can be generated by preparing program in Arduino for interfacing sensors and Processing 3 for measurement readings of testing. Sensors gives accurate data if they are properly calibrated and assembled on respective existing machine instruments. Computerized universal testing machine works by applying gradual load on specimen of known geometry which is fixed within jaws of upper and middle crossheads or middle and lower crossheads operated by hydraulic actuation system and electric motors. The results stress strain data and mechanical material properties obtain from this system is simulated in real time by creating Graphical User Interface in Processing 3.