Aircraft Design Automation and Subscale Testing With Special Reference to Micro Air Vehicles

University dissertation from Linköping : Linköping University Electronic Press

Abstract: This dissertation concerns how design automation as well as rapid prototyping and testing of subscale prototypes can support aircraft design. A framework for design automation has been developed and is applied specifically to Micro Air Vehicles (MAV). MAVs are an interesting area for design automation as they are an application where the entire design, from requirements to manufacturing, can indeed be automated. From a complexity point of view it can be considered to be similar to conceptual design of manned aircraft.The created design optimization framework interfaces several software systems to generate MAVs to optimally fulfil specific mission requirements. The goal has been to find a method for MAV design and optimization from a holistic viewpoint, i.e. not a method for optimizing single subsystems, such as motor or propeller, but a method that embraces all disciplines of MAV design. Key drivers have been the use of off-the-shelf components wherever possible and to optimize the geometric shape not just from an aerodynamic perspective, but also to consider internal component placement and stability criteria. The optimization technique chosen is a multi-objective genetic algorithm. Finally, a novel method for direct digital manufacturing of MAVs is proposed.The utility of the framework has been demonstrated with several case studies on MAV design. The propulsion system is identified as most influential on MAV performance and thus is where it is most important to have accurate models. For this reason the models used in the framework are experimentally validated. The influence of atmospheric winds and turbulence on MAV performance is also experimentally investigatedThe subscale testing efforts are aimed at reducing cost and increasing the usability of flight testing with subscale vehicles. Data acquisition system design is described and low-cost testing methods are presented, such as car top testing or in-flight flow visualization. Two subscale flight projects are also presented.