Biomechanics of the Insect Flight Motor

This thesis presents novel insights into the free-flight kinematics of pterygotes; a new standard for reporting high-precision insect body, leg and wing kinematics, the importance of non-wing appendages on flight stability, methods for handling large datasets and time-varying parameters to test against independent variables, and how insects generate extreme manoeuvres. Research here was facilitated by the development and use of a new ten high-speed camera rig to acquire footage, followed by a completely automated voxel-carving package to report kinematics of unprecedented resolution including wing torsion and bending. Anopheles (mosquito) underwent substantial wing deformation with varying ambient temperature and stimuli to encourage flight manoeuvres. Wing kinematics were significantly different between male and female subjects. Meanwhile, subjects were able to reduce their stroke amplitudes to angles lower than any other flying insect previously reported in literature. With a supplementary leg tracker and centre of mass measurements, mosquito legs were also shown to contribute substantially to flight stability in the roll axis, whilst damaged mosquitoes that had experienced leg loss adjusted the kinematics of remaining limbs. Wingbeat frequency increased with temperature but plateaued at different temperatures for male and female subjects. Whilst, overall body kinematics did not correlate with temperature. This subsequently led to the Fourier fitting and principal component analysis of the same mosquito dataset, to create descriptor wingbeats to test the effect of temperature and estimate other summary parameters (e.g., stroke plane) while compacting data. Aerial hunters, Coenosia (killer fly), performed a large range of manoeuvres from backwards to upside down flight in the presence of one of two different configurations of artificial prey available. Incredibly high angular rates and accelerations were achieved whilst maintaining subtle changes in wing kinematics. These insights may feed into topics of flight control, aerodynamics and the development of micro-air vehicles.