The TTL pulse stream is created by a specific number of stripes arranged circumferentially on the shaft. The output of the torsional converter is voltage proportional to angular velocity which can be recorded and analyzed. The torsional stress is determined using torsional velocity data as described above, along with additional signal processing and computations. In order to determine torsional stress, angular deflection over a known length of shaft must be measured. This is done by configuring two similar torsional velocity systems as described above.
Angular displacement is determined by integrating the angular velocity values.
Thus, subtracting the angular displacement of one sensor from the other provides this value. Dynamic and static torque can also be derived. The instrumentation used to perform measurements are described below. Figure 1 is a diagram of the instrumentation configuration. The two infrared sensors are attached to deck plating at the shaft and aimed at the respective sets of strips.