Research On Stability Of Small-Scale Unmanned Aerial Vehicle Based On Lyapunov Exponents

The instability phenomenon of small-scale unmanned aerial vehicles takes place frequently due to the complicated airflow in near-earth space, which easily leads to the stability problems, such as out of control, shaking and loss accuracy of command tracking. The present study provides a simple dynamical equation based on small-scale unmanned aerial vehicles by employing the pseudo velocity vector to analyze this dynamic characteristic, which directs at small-scale unmanned aerial vehicles with unique characteristics such as multivariable and non-linear, making it difficult to establish the complex dynamics equation. In addition, the further dynamical modeling and simulation analyses based on this simple dynamical equation are specially investigated. On the basis of the above study, the Lyapunov function is difficult to build and the complex dynamics equation based on Lyapunov's second analysis system is difficult to solve. However, the optimization of structure parameters is of great significance to improve the movement stability of unmanned aerial vehicles. Therefore,this paper builds the quantitative relationship between the structural parameter of aerial vehicles and their system stability based on Lyapunov exponent theory from viewpoint of structural parameter design. Moreover, the reliability and stability of unmanned aerial vehicles under service could be promoted by optimizing the mechanical structure and control system based on the analysis of the quantitative relationship. Finally, this study focuses on the take-off and yawing stage of the unmanned aerial vehicles respectively and then the conclusion can be summarized through the experimental verification and theoretical analysis. Compared to Lyapunov's second method, the main advantage of Lyapunov exponents are constructive, which makes the stability analysis of complex nonlinear system possible.