Present work establishes a new formulation to determine the dynamic characteristics of a cracked beam, where the change in second moment of area is considered. The present formulation considers the shift in the neutral axis of the cracked beam-element, which has been ignored previously. Consequently, an in-depth analysis is conducted to understand the effectiveness of this new approach. The results obtained shows a promising scope for the adoption of the updated formulation for various cross-sections and future research work.

Semicircular canal plays an important role in sensing of human body orientation. Cupula is the system in semicircular canal responsible for sensing rotational head movements. It is excited by the flow of endolymph caused due to inertia of head movement. There are various disorders related to semicircular canal, the most common disorder is Benign Paroxysmal Positional Vertigo (BPPV). Present work focuses on determination of response of cupula due to endolymph flow in the horizontal semicircular canal. Variation of pressure generated on cupula by endolymph for different rotational velocity of head is studied and reported. Response of cupula with appropriate boundary conditions is extracted. Results obtained open up new area of research in better understanding the behavior of cupula with endolymph flow. It may aid in the betterment of curing BPPV.

Persistent exposure to whole body vibrations is the fundamental cause for lower back pain and disc degeneration. With an increasing amount of population exposed to whole body vibrations, a significant number of people experience fatal spine diseases. Substantial research is carried out to reduce the risk of spinal injuries. The dynamic characteristics of the cervical, thoracic and lumbar (CTL) region are studied extensively as individual sections of the spine. Few studies have focused on the CTL spine as an assembly of the three segments. In the present work, an authentic three dimensional geometrical model of the cervical, thoracic and lumbar spine is developed in mimics considering its natural curvature and the intervertebral discs are modeled in Design modeler. The natural frequency and mode shapes of the CTL spine are extracted using free vibration modal analysis considering 4.5 kg point mass on C1 vertebra and distributed mass of 40 kg on the CTL spine in Ansys Workbench. Six natural frequencies and their corresponding vibration modes are obtained from the finite element model. The results of this study aims to provide a reliable model for further biomechanical analysis and ergonomics.

Spherical parallel manipulator (SPM) finds in many engineering applications like aerodynamic simulators, medical devices, precision machine tools and telescopes. The dynamic characteristic of SPM plays an important role in determining the performance and stability of the manipulator. The present paper reports modal analysis of a 3-DOF SPM with full-circle twist model. A solid model of the SPM is developed using Unigraphics Nx and imported into Ansys for modal analysis. First, three fundamental natural frequencies and mode shapes are extracted. Natural frequencies are validated with the experimental results.

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