Guest Speaker: Bruce W Drinkwater
School of Electrical, Electronic and Mechanical Engineering
University of Bristol
Professor Bruce Drinkwater founded the Ultrasonics and Non-Destructive Testing Research Group at the University of Bristol in 1996. The group is now internationally recognised and has 6 academic staff and c.30 PhD students and post-docs. He is Director of the EPSRC Centre for Doctoral Training in Future Innovation in Non-Destructive Evaluation and Editor-in-Chief of the Journal Non-Destructive Testing and Evaluation International, the leading journal in this field. He has pioneered industrial applications of ultrasonic arrays in non-destructive testing, as well as developing innovative devices for condition monitoring and particle manipulation. His research has been commercialised through licencing and spinouts and changed industrial practice by inclusion in international standards. In 2024 he was elected a Fellow of the Royal Academy of Engineering.
Abstract
Acoustic (ultrasonic) beams are used widely in medical and engineering imaging where the focal spot size determines resolution. Acoustic beams are also key to techniques that use acoustic radiation forces to manipulate microscale objects - acoustical tweezers or tractor beams. Here, the beams must be carefully shaped to create the correct local force field that traps the object. Acoustic holograms lead to exquisite control of beam shape and force field yet are static. Phased arrays of individual emitters can provide dynamic beam control but are currently lower in resolution. This talk first describes these concepts, then explores the complex question of how to make the perfect acoustic tweezer. Alongside this, biomedical applications of these devices are described, including the creation of artificial muscle tissue. The talk concludes with a discussion of future applications such as the use of acoustical tweezers within the human body for things such as targeted drug delivery.
