Displacement measurement
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
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
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
- ^ 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.
- ^ 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.
- ^ "transducer". Merriam-Webster.com Dictionary. Merriam-Webster.
- ^ 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
- ^ 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
- ^ 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
- ^ 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.