Jump to content

Displacement measurement

From Wikipedia, the free encyclopedia
(Redirected from Displacement sensor)

Displacement measurement is the measurement of changes in directed distance (displacement). Devices measuring displacement are based on displacement sensors, which can be contacting or non-contacting.[1] Some displacement sensors are based on displacement transducers,[2] devices which convert displacement into another form of energy.[3]

Displacement sensors can be used to indirectly measure a number of other quantities, including deformation, distortion, thermal expansion, thickness (normally through the combination of two sensors), vibration, spindle motion, fluid level, strain and mechanical shock.[1]

Displacement sensors exist that can measure displacement on the order of nanometers or smaller.[1]

Application

[edit]

Displacement receivers can be used to study and observe the stress waves passing through a material after it is struck.[4] This can be used to assess fire damage to reinforced concrete.[4]

Displacement transducers are often used to measure vibration.[5]

Types

[edit]

Optical displacement sensors exist, using reflected light to determine distance.[6]

An ultrasonic displacement sensor is a kind of displacement sensor.[6] These measure the distance to targets by emitting low-frequency sound waves and measuring the time they take to return.[6]

Displacement sensors can be made using linear variable differential transformers.[6]

Strain gauges can be used as the base for small displacement transducers on the order of 0 to 10 mm.[7]

In music, certain music keyboards can be considered to measure displacement in the sense that they respond to displacement, rather than velocity (as is more commonly the case).[citation needed]

Examples of displacement-responding sensors include the mechanical action of tracker organs, as well as the force-sensing resistors found in music keyboards that had polyphonic aftertouch capability. Polyphonic aftertouch is no longer a feature of presently manufactured keyboards, but certain older models such as the Roland A50 featured a pressure sensing resistor, similar in principle-of-operation to a carbon microphone, in each key.[citation needed]

References

[edit]
  1. ^ a b c Leach, Richard (2014-01-01), Leach, Richard (ed.), "Chapter 5 - Displacement Measurement", Fundamental Principles of Engineering Nanometrology (Second Edition), Micro and Nano Technologies, Oxford: William Andrew Publishing, pp. 95–132, ISBN 978-1-4557-7753-2, retrieved 2024-12-04, At the heart of all instruments that measure a change in length, or coordinates, are displacement sensors. ... Displacement sensors can be contacting or non-contacting, and often can be configured to measure velocity and acceleration.
  2. ^ Mendelson, Yitzhak (2012-01-01), Enderle, John D.; Bronzino, Joseph D. (eds.), "Chapter 10 - Biomedical Sensors", Introduction to Biomedical Engineering (Third Edition), Biomedical Engineering, Boston: Academic Press, pp. 609–666, ISBN 978-0-12-374979-6, retrieved 2024-12-04, Displacement transducers are typically used to measure physical changes in the position of an object or medium.
  3. ^ "transducer". Merriam-Webster.com Dictionary. Merriam-Webster.
  4. ^ a b Hsu, K., Cheng, C., Hsu, S., & Yu, P. (2022). Rapid assessment of fire damage to reinforced concrete structures using the surface wave method with contact and non-contact receivers. International Symposium on Non-Destructive Testing in Civil Engineering (NDT-CE 2022), 16-18 August 2022, Zurich, Switzerland. e-Journal of Nondestructive Testing Vol. 27(9). https://doi.org/10.58286/27289
  5. ^ Cheatle, Keith (2006). "4.4: Displacement Transducers". Fundamentals of Test Measurement Instrumentation. ISA--Instrumentation, Systems, and Automation Society. ISBN 978-1-55617-914-3.. Excerpt accessed through GlobalSpec
  6. ^ a b c d Paul, Sudip; Saikia, Angana; Majhi, Vinayak; Pandey, Vinay Kumar (2022-01-01), Paul, Sudip; Saikia, Angana; Majhi, Vinayak; Pandey, Vinay Kumar (eds.), "Chapter 3 - Transducers and amplifiers", Introduction to Biomedical Instrumentation and Its Applications, Academic Press, pp. 87–167, ISBN 978-0-12-821674-3, retrieved 2024-11-30
  7. ^ Chatterjee, Karunamoy; Mahato, Sankar Narayan; Chattopadhyay, Subrata; De, Dhananjoy (2017-01-01). "High accuracy displacement measuring system using strain gauge based displacement sensor and direct sequence spread spectrum techniques in data acquisition system". Instruments and Experimental Techniques. 60 (1): 154–157. doi:10.1134/S0020441217010055. ISSN 1608-3180.