Sensors allow detection, analysis, and recording of physical phenomenon that are difficult tootherwise measure by converting the phenomenon into a more convenient signal. Sensorsconvert physical measurements such as displacement, velocity, acceleration, force, pressure,chemical concentration, or flow into electrical signals. The value of the original physicalparameter can be back-calculated from the appropriate characteristics of the electrical signal(amplitude, frequency, pulse-width, etc.). Electrical outputs are very convenient because thereare well known methods (and often commercially available off-the-shelf solutions) for filteringand acquiring electrical signals for real-time or subsequent analysis