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Today, measurement of strain plays a crucial role in different areas of research such as manufacturing, aerospace, automotive industry, agriculture, and medical. Many researchers have used different types of strain transducers to measure strain in their relevant research fields. Strain can be measured using mainly two methods (i.e., electrical strain sensors and optical strain sensors). Electrical strain sensors consist basically of strain gauges, piezo film, etc. In electrical strain sensors, the strain gauge is one of the oldest and reliable strain sensors which are available in different types (i.e., wire strain gauge, foil strain gauge, and semiconductor strain gauge). Piezofilm is also playing an important role in the field of strain measurement due to easy availability and less cost.

Large wave drag and high surface heating are the major concerns of hypersonic flows. Hence, development of force measurement technique or prediction of force has always remained a promising research topic in this field. Present studies also deal with force prediction techniques and force balance calibration methodology for ground testing in an impulse test facility. A blunt double cone model is fabricated along with a three component accelerometer force balance. Impulse hammer hits are made on different locations of this test model. In these calibration experiments, the applied impulse and acceleration responses from three accelerometers are recorded. These calibration tests are repeated multiple times to apply hammer hits of different magnitude. All the input and corresponding output singles are then processed first to arrive at the impulse response function or correlation between input and outputs. Then the force recovery techniques are applied to recover the axial and normal forces generated during application of one of the calibration forces. The experimentally recovered force signals from different techniques are compared and then the accuracy of these predictions is estimated using different error estimation techniques. Such studies are found essential not only in defining the most accurate force prediction technique but also in understanding the time required for prediction by a particular technique. Additionally, such studies essentially helps to improve a force prediction algorithm.