Assess your understanding of Mechanical Shock Testing
- The most appropriate "classical" pulse shape to describe impacts with or retardations by, a linear rate system, e.g. Impacts involving resilient structures is:
(a) Half sine (b) Final peak sawtooth (c) Trapezoidal (d) Initial peak sawtooth (e) Rectangular (f) Triangular. - What characteristic of compression design accelerometers makes them unsuitable for shock measurements?
(a) High output sensitivity (b) Base strain sensitivity (c) Non-linearity (d) Phase shift (d) Frequency response - The advantage of a terminal peak sawtooth test pulse is that:
(a) it is easily generated using an electromagnetic shaker (b) it transmits most energy into the test structure (c) there are no nulls in its shock spectrum response (d) it has a large residual component - Excitation of a fixture's resonant frequencies during shock testing can have an effect on the attached test item as follows:
(a) the item may be over tested (b) the item may be under tested (c) there will be no effect on the test item. - The figure below illustrates the initial Shock Response Spectrum obtained from which of the following "classical" shock pulses prescribed in many specifications:
(a) Trapezoidal (b) Half sine (c) Final peak sawtooth.
- Calculate the shock load in Newtons for a critical component of mass 2kg and natural frequency 200Hz which is exposed to the shock response spectrum shown below.
