MECHENG 4Q03 Lecture Notes - Time Derivative, Phase Angle, Accelerometer

• School: McMaster University
• Department: Mechanical Engineering
• Course: MECHENG 4Q03
• Professor: veldhu

Document Summary

Lecture 6 - lumped mass assumptions: lumped analysis - inertia effect of stiffness elements. Generally ignore mass in stiffness elements: this assumption can lead to significant error, especially if the mass of the stiffness element is not negligible compared to system mass. Calculate an equivalent mass value located at the end. Motion that is repeated after equal intervals of time. Motion can be very complicated but it must repeat. Movement of a vibrating object from equilibrium, to one extreme position, back through equilibrium, to the other extreme position, and back to equilibrium: cycle. Descriptors: amplitude a, phase angle ( , period (s) Maximum displacement of the vibrating body from equilibrium. Shift in corresponding points of wave shape. Time taken to complete one cycle: frequency f (hz) = 1 / period. Number of cycles per unit time (cycles/sec) For a rotational system relates to rpm: circular frequency (rad/s) = 2 f (hz, natural frequency.