Principles of pressure transducers, resonance, damping and frequency response

摘要: Abstract The most commonly used pressure transducer in clinical practice is the piezoresistive strain gauge. usually placed some distance from patient and signal conveyed by a fluid-filled manometer. Deformation of silicon wafer diaphragm produces an alteration electrical resistance, which measured Wheatstone bridge. To maximize accuracy, any must be correctly set up zero balanced before use. Resonance occurs when frequency driving oscillations matches natural measuring system, results significant measurement error. may raised incorporating stiff diaphragm, reducing mass fluid manometer pathway. Optimal damping invasive system allows accurate at frequencies to two-thirds frequency. Accurate representation arterial waveform achieved summation first eight harmonics using Fourier analysis. Eight times fundamental heart rate represents minimum required bandwidth for system. response, or flat range highest that can overshoot error (over 10%) occurs. An optimally damped manometric with resonant 36 Hz more will accurately reproduce shape 180 beats/min.