Multi-Point Optimisation of a Propulsion Set as Applied to a Multi-Tasking MAV

Abstract : This study focus on optimisation of electric propulsion system for a given mission with multiple working conditions. A program called Qpoptimizer is developed and presented which can analyse and couple numerous motors and propellers from databases for a specific mission. It can also design a custom propeller by using the motor and airfoil databases. Qpoptimizer uses Qprop and Qmil opensource propeller analyses and design programs from Mark Drela. Motor and propeller couples are simulated at each predefined working condition and given a score according to their total performance. This methodology ensures the optimisation of the selected motor and propeller couples to be valid and optimum not only for one working condition (for example: cruise condition) but for all of them (take-off,high speed,etc...). Theoretical models and experimental measurements are explained in order to generate the required databases for the existing motors, propellers and airfoils. Finally, an application of the Qpoptimizer program on a real mission is also presented where a custom propeller is optimised according to the weighted mission working conditions.