A simple and cost effective method to measure Young’s modulus of a rod using moiré pattern

This paper presents a moiré pattern based method for the measurement of Young’s modulus of the material of a rod. The moiré pattern is created with two transparent sheets with parallel lines printed over them and having a slight difference in their periodicity. One of these two sheets is attached to the rod whose Young’s modulus is to be measured, another one is held fixed very close to the previous one so that the moiré pattern is formed. When a load is applied to bend the rod, the relative angle between the two sheets changes. This change in turn changes the orientation of the moiré pattern. By measuring the change in the angle in the moiré pattern, the change in the relative angle between the two sheets is measured and hence the amount of bend in the experimental rod is measured. From this change in angle, Young’s modulus of the material of the rod is calculated. The method described here is simple and cost effective as the method uses very little apparatus and also without any additional processing. The results show that the proposed moiré pattern based Young’s modulus measurement has better accuracy compared to similar methods.