Design, flight dynamic analysis and hover control of a vertical take-off and landing micro air vehicle
Date of Issue2009
School of Mechanical and Aerospace Engineering
A ducted fan Vertical Take-off and Landing (VTOL) Micro Air Vehicle (MAV) is developed. The vehicle is equipped with a wing that can be rotated in the pitch direction (variable incidence). This feature is expected to suppress the altitude loss during transition and to reduce the gust effect in hover. The selected configuration is capable to yield satisfactory aerodynamic performances and satisfy the static stability requirements in the cruise-flight. The variable-incidence wing feature is found to yield a higher lift and a lower drag at high angles of attack flight. In cruise and small angles of attack, the dynamics of the MAV are similar to those of a conventional aircraft. In hover and high angles of attack, the MAV is inherently unstable. An automatic control system is developed to stabilize the MAV in hover and to maintain the position of the MAV under wind disturbances. The Single Input Single Output (SISO) root locus technique is applied to design the control system. The pitch and yaw attitude controls are used as inner loops to achieve stability. The velocity and position controls are put in the outer loops of the attitude controls. The performance of the controlled vehicle under crosswind disturbances is also examined.