Add a new wiki page under the Physical principles of sensing and write about the physics behind the scene. You may try to find answers to the following questions:
- Does your sensor convert the stimulus directly into electric output?
- What steps are required to transform the signal into electric output?
- What types of physical effects and energies are involved in the sensing and in transformation?
- How the sensing and transformation can be modeled mathematically or physically?
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- Introduction
There are many different types of sensing elements used in accelerometers. Hall effect one of the the sensing elements that is used in the design of accelerometers. I find this type of sensing interesting, and therefore, in this wiki page I will discuss briefly the physical principle of sensing based on Hall effect.The Hall effect was discovered in 1879 by Dr. Edwin Herbert Hall while he was at Johns Hopkins University in Baltimore. While trying to verify electron flow theory proposed by Kelvin, he found that when a magnet was placed with its fields being perpendicular to one face of a thin rectangle of gold which current was flowing through, a potential difference appeared at the opposite edges. What he found is that this voltage is proportional to the current flowing through the conductor, and the flux density or magnetic induction perpendicular to the conductor.
- Theory of the Hall effect
- Hall effect accelerometers
References
- Bridgemen, P. W. (1939). Biographical Memoir of Edwin Herbert Hall. National Academy of Sciences.
- Jacob Fraden. Handbook of Modern Sensors: Physics, Designs, and Applications (4th edition). Springer Publishing
- http://farside.ph.utexas.edu/teaching/302l/lectures/node74.html
- http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/hall.html
- http://sensing.honeywell.com/honeywell-sensing-sensors-magnetoresistive-hall-effect-applications-005715-2-en.pdf