David is a Senior Lecturer in the Department of Bioengineering, Imperial College London. In his research, David combines his two main passions: his love for animals, and his admiration for physics. Together with his group, he investigates the influence of mechanical constraints on the performance, behaviour and evolution of arthropods (and sometimes larger animals or even plants!). Prior to this appointment, David completed an interdisciplinary degree in Biomimetics at the University of Applied Sciences, Bremen, earned his PhD in the Department of Zoology at Cambridge University under Prof Walter Federle (until 2015), and conducted independent research at the Department of Engineering, Cambridge, funded by the Denman Baynes Senior Research Fellowship awarded by Clare College (until 2018). Every day, David is deeply grateful that he has a job in which he can follow his interest, and that he gets to work with and learn from the passionate members of his research group.
Biomechanics of controllable attachment in climbing animals
Abstract: Many small vertebrates and arthropods are able to run with sticky feet, and must hence be able to rapidly switch between strong attachment and effortless detachment. The timescale over which contacts are formed and broken precludes chemical control. Instead, terrestrial climbing animals appear to rely on mechanical switches. Recently, strong evidence has emerged that at least some of these switches are universal: Whether adhesive pads are hairy’, smooth’,wet’ or `dry’ pads, there appears to exist a linear relationship between the shear force, applied in parallel to the surface, and the adhesive force, normal to the surface, required to detach them. This ‘shear-sensitivity’ provides a rapid mechanical switch, enables larger animals to maintain approximately constant safety factors despite smaller surface-to-volume ratios, and has implications for optimal step coordination patterns during climbing on vertical and inverted substrates. The control of adhesion via shear forces is deeply integrated with the anatomy and locomotion of climbing animals, and involves both active neuro-muscular control, and rapid passive responses. The resulting dynamic adhesive systems are robust, reliable, versatile and nevertheless remarkably simple. They may thus serve as suitable inspiration for the design of climbing robots.