Discrete mechanics and optimal control optimization of flapping wing dynamics for Mars exploration

Mars exploration is currently in the focus of scientific community interests. The attempts for efficient exploration will probably include the unmanned aerial vehicle in the near future to explore the places inaccessible by rovers. Since the Mars atmospheric conditions render the conventional rotary and fixed wing aerial vehicles inefficient, the insect-type flapping concept emerged as a promising solution. This is due to the fact that insects on Earth fly efficiently at the same values of Reynolds number that the aerial vehicle for Mars exploration would exhibit. The paper proposes the novel design optimization algorithm for development of insect-type aerial vehicle capable of flight in Martian atmosphere. The optimization procedure utilizes the novel flapping pattern optimization based on a quasi-steady aerodynamic model, combined with the discrete mechanics and optimal control framework. A test case of a flapping vehicle with fruit fly-like wings, performing a standstill hovering on Mars, is analyzed in detail. The fruit fly wing is scaled with a wide range of uniform scaling factors and optimized for hovering on Mars in the conditions of bioinspired Reynolds number range. Apart from the single optimal combination for the standstill hovering with fruit fly-like wings, the algorithm also found different efficient flapping patterns for a wide range of scaling factors, providing directions for design of flapping aerial vehicles for Mars. (C) 2020 Elsevier Masson SAS. All rights reserved.