Simulator Development for Transition Flight Dynamics of a VTOL MAV

Abstract

This paper presents the simulation and validation of models for transition between forward flight and hover for a micro air vehicle (MAV). A dynamical simulation environment is developed, based on measured aerodynamic properties of a fixed-wing tail-sitter MAV with vertical take-off and landing (VTOL) capabilities. The simulator is validated against recorded flight data of transition from forward flight to hover using the physical platform. Specifically, the flight transition maneuver in the vertical plane (vertical-to-horizontal and horizontal-to-vertical) is studied in detail. The development and evaluation of a VTOL MAV called Mini-Vertigo 2 (MV2) is presented. A non-linear longitudinal dynamic model of MV2 flight is derived, and semi-empirical aerodynamic formulas for thrust, lift, drag and pitching moment based on wind tunnel testing are applied to the dynamic model. Nonlinearities during transition to/from hover are addressed, and (using the developed dynamic model) a numerical vehicle dynamic simulator is presented. The MV2 autopilot is discussed and flight test data are presented. Flight data from pitch-up maneuvers was compared to results of simulations. This comparison enables the future application of the simulation system throughout the flight envelope. This work presents a significant extension of [1].

Longitudinal Aerodynamics of a Vertical Takeoff and Landing Micro Air Vehicle

“…Data from this study were used to determine parameters of a semiempirical model of wing aerodynamics, which was applied to a successful MAV dynamics simulator [9]. The simulator helps inform design tradeoffs, especially with regard to transition maneuvering (between horizontal and hovering flight).…”

“…MV2 is also capable of autonomy, which requires a functional autopilot. Autopilot control algorithms were addressed in a previous paper [9]. The algorithms were based on data from the present study.…”

Fixed-wing UAV with transitioning flight capabilities : Model-Based or Model-Free Control approach? A preliminary study

“…We apply exactly the same steps from equation (8) to equation (11). This time, for a second-order dynamic described in equation (12).…”

“…Let's consider a single state dynamic, for example the pitch angle θ, that is controlled by symmetric flap deflections (δ l ,δ r ), see Figure 3. Thus, by analogy with equation (12) and from Figure 6, the Ultra-Local Model can be represented by the following equation :…”

“…Therefore, defining an appropriate model structure that is both reliable in terms of aerodynamic interaction between propeller and wing, and that can also model post-stall intricacies effects, remains a complex work. Nevertheless, there are recent efforts validating a tail-sitter MAV model by wind tunnel campaign and experimental flight tests for the entire flight envelope [10] [11] [12]. These specific aerodynamic characteristics were computed to design a series of gain matrices which are then used in a scheduled Linear Quadratic Regulator [11].…”