[HN Gopher] Taylor Series and Accelerometers ___________________________________________________________________ Taylor Series and Accelerometers Author : signa11 Score : 18 points Date : 2020-08-12 08:55 UTC (14 hours ago) (HTM) web link (jeremykun.com) (TXT) w3m dump (jeremykun.com) | [deleted] | kayson wrote: | Using differences to avoid non-linearity is a pretty common | technique used across EE, especially circuit design. Transistors | are very non-linear and circuits like amplifiers have problematic | squared terms. However, they're almost always built | "differentially": there are both positive and negative input | terminals, and positive and negative output terminals. The | difference of the output voltages is an amplified version of the | difference of the input voltages. Because the squared term at | each terminal is the same polarity, subtracting them cancels it | out very well. In practice, you're limited by how well the | positive and negative paths match, and the mismatch allows some | second order term to leak out. Unfortunately, this does not help | with the third order terms. | | See: https://en.wikipedia.org/wiki/Differential_amplifier | https://en.wikipedia.org/wiki/Third-order_intercept_point | ISL wrote: | To answer the post's final question: Yes. It is quite common to | design instrumentation to cancel systematic uncertainties or | nonlinearities to leading order. Fancier arrangements go to | higher orders. | | In the particular case of the differential capacitor, that form | of differential measurement is particularly common -- if one non- | linear system can paired with a symmetric partner with equal and | opposite nonlinearity, the leading-order non-linearities are | suppressed (to the extent that the matched pair are actually | matched). | | An easy-to-understand example of the compensation of linear | effects is the temperature-compensated pendulum clock: | https://en.wikipedia.org/wiki/Gridiron_pendulum ___________________________________________________________________ (page generated 2020-08-12 23:00 UTC)