The the Academy of Science of South Africa and the Royal Society of South Africa invite you to a webinar by Professor David Limebeer, FRSSAf Electrical & Information Engineering, University of the Witwatersrand on ‘Spiders that fly’.
Date: Wednesday 20th May 2026
Time: 17h00
Abstract: Slingshot spiders use their web as a catapult to ensnare prey. Given an arbitrary 3D array of anchor points, we will analyse the construction and design optimisation of the web. The spider is faced with a multi-dimensional optimisation problem that involves balancing the need for a fast web response, damage resilience and web-loading forces. The web’s dynamic response depends on the material properties of the web silk, as well as its geometric layout. Given the high release acceleration and velocity, a detailed aerodynamic damping analysis is required. We will invoke the aerodynamics used to study the drag on nineteenth century clock pendula.
About the Speaker: David J. N. Limebeer FRSSAf received a BSc (Eng) (cum laude) degree in electrical engineering from the University of the Witwatersrand, MSc (Eng) (cum laude) and PhD degrees from the University of Natal, the DSc (Eng) from the University of London and an MA from the University of Oxford (conferred by resolution). He was a post-doc researcher at the University of Cambridge between 1980 and 1984. He then joined the Electrical and Electronic Engineering Department at Imperial College. He was promoted to Professor in 1993, Head of the Control Group in 1996, and was Head of Department between 1999 and 2009. He then moved to Oxford University as Professor of Control Engineering and Professorial Fellow at New College Oxford. He is now a Distinguished Professor at the University of the Witwatersrand. His research interests include applied and theoretical problems in control systems and engineering dynamics. He is a Fellow of the IEEE, the IET, the Royal Academy of Engineering, the City and Guilds of London Institute, the South African Academy of Engineering and the Royal Society of South Africa. He was co-recipient of two South African Institute of Electrical Engineering prizes, the 1983 O. Hugo Schuck best paper award, the 2008 William Mong Distinguished Lecture, the 2015 IET Tustin Lecture, the Honeywell International medal. He holds a National Research Foundation of South Africa A1 research rating.
ALL WELCOME – PLEASE FORWARD TO COLLEAGUES AND FRIENDS
– a video of this talk will appear on our website about a week after the event.
Website: www.royalsocietysa.org.za
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