Sound Field Design for Transducer Array-Based Acoustic Levitation
Doktorsavhandling, 2022
This thesis is about combining these three concepts. The necessary criteria for levitation to take place are described, using radiation pressure from sound waves in air as the physical mechanism by which the levitation forces are produced. Ultrasonic transducer arrays are modeled using analytical descriptions for the wave propagation, as well as for the predictions of the radiation forces on spherical objects of various sizes. The sound fields required to successfully levitate objects are obtained by numerically optimizing the magnitudes and phases of the elements in the mono-frequent transducer arrays. This is achieved by deriving design criteria from intuitive considerations of the conditions needed for levitation, quantifying these criteria as a
single valued cost function which is minimized with a Quasi-Newton method.
The thesis is focused on two main aspects: how to define a suitable cost function for a single levitation trap, and how to levitate multiple objects via mutual quiet zones. The design criteria for a trap are described using a vector field approach, representing properties of the force field with invariant quantities evaluated at the desired levitation position. These quantifiers are scaled by the characteristic quantities of the system and transformed to a satisficing cost function, which avoids over-optimization by reducing the prioritization of a particular criterion when closer to fulfilled. Multiple objects are levitated by superposing sound fields with mutual quiet zones, i.e. each sound field has a trap for one object and quiet zones where all the other objects will be.
Nonlinear Acoustics
Sound Field Design
Transducer Arrays
Acoustic Levitation
Numerical Optimization
Författare
Carl Andersson
Chalmers, Arkitektur och samhällsbyggnadsteknik, Teknisk akustik
A Method for Simultaneous Creation of an Acoustic Trap and a Quiet Zone
Proceedings of the IEEE Sensor Array and Multichannel Signal Processing Workshop,;Vol. 2018-July(2018)p. 622-626
Paper i proceeding
Minimum trap separation for acoustical levitation using phased ultrasonic transducer arrays
Proceedings of the International Congress on Acoustics,;Vol. 2019-September(2019)p. 1117-1123
Paper i proceeding
Acoustic Levitation from Superposition of Spherical Harmonics Expansions of Elementary Sources: Analysis of Dependency on Wavenumber and Order
IEEE International Ultrasonics Symposium, IUS,;Vol. 2019-October(2019)p. 920-923
Paper i proceeding
Reducing Spiraling in Transducer Array Based Acoustic Levitation
IEEE International Ultrasonics Symposium, IUS,;Vol. 2020-September(2020)
Paper i proceeding
Creation of Large Quiet Zones in the Presence of Acoustical Levitation Traps
IEEE International Ultrasonics Symposium, IUS,;(2021)
Paper i proceeding
Acoustic levitation of multi-wavelength spherical bodies using transducer arrays of non-specialized geometries
Journal of the Acoustical Society of America,;Vol. 151(2022)p. 2999-3006
Artikel i vetenskaplig tidskrift
Levitation with localised tactile and audio feedback for mid-air interactions (Levitate)
Europeiska kommissionen (EU) (EC/H2020/737087), 2017-01-01 -- 2020-12-31.
Ämneskategorier
Beräkningsmatematik
Fysik
Strömningsmekanik och akustik
Signalbehandling
ISBN
978-91-7905-593-6
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5060
Utgivare
Chalmers