title: Quasi-steady state aerodynamics of the cheetah tail.
abstract: During high-speed pursuit of prey, the cheetah (Acinonyx jubatus) has been observed to swing its tail while manoeuvring (e.g. turning or braking) but the effect of these complex motions is not well understood. This study demonstrates the potential of the cheetah's long, furry tail to impart torques and forces on the body as a result of aerodynamic effects, in addition to the well-known inertial effects. The first-order aerodynamic forces on the tail are quantified through wind tunnel testing and it is observed that the fur nearly doubles the effective frontal area of the tail without much mass penalty. Simple dynamic models provide insight into manoeuvrability via simulation of pitch, roll and yaw tail motion primitives. The inertial and quasi-steady state aerodynamic effects of tail actuation are quantified and compared by calculating the angular impulse imparted onto the cheetah's body and its shown aerodynamic effects contribute to the tail's angular impulse, especially at the highest forward velocities.
authors.affiliation: Department of Electrical Engineering, University of Cape Town, Cape Town 7701, South Africa a.patel@uct.ac.za.
authors.forename: Amir
authors.identifier: http://orcid.org/0000-0002-2344-4179
authors.initials: A
authors.lastname: Patel
authors.affiliation: Department of Electrical Engineering, University of Cape Town, Cape Town 7701, South Africa.
authors.forename: Edward
authors.initials: E
authors.lastname: Boje
authors.affiliation: Department of Electrical Engineering, University of Cape Town, Cape Town 7701, South Africa.
authors.forename: Callen
authors.initials: C
authors.lastname: Fisher
authors.affiliation: Department of Integrative Biology, University of California, Berkeley, Berkeley, CA 94720-3140, U.S.A.
authors.forename: Leeann
authors.initials: L
authors.lastname: Louis
authors.affiliation: Department of Epidemiology, National Zoological Gardens of South Africa, Pretoria 0001, South Africa.
authors.forename: Emily
authors.initials: E
authors.lastname: Lane
keywords: Aerodynamics; Cheetah; Inertia; Manoeuvrability; Tail