Detection of Higher Harmonics in a Slider Crank Mechanism of Variable Obliquity Ratio and its Use in the Determination of Displacement Transmissibility

The present paper deals with the design and manufacture of a slider crank mechanism with a variable obliquity ratio. It uses a double eccentric to serve this purpose. The slider crank mechanism can be operated at various speeds and different obliquity ratios. An accelerometer attached to the slider helps obtain its acceleration. The presence of higher harmonics is detected using fast Fourier transforms. The experimentally obtained values are compared with standard theoretical results. Further, a cantilever can be fixed to the slider under displacement excitation. Accelerations measured at the root and tip of the cantilever are used to calculate displacement transmissibility. The experimentally obtained values are compared with those obtained using finite elements. It is expected that such an approach will boost the interest of the students as it bridges theory with experimental work, which is so vital for engineering education.