Linear parameter varying control of unmanned quadrotor helicopter with mass variation and battery drainage

In this paper, a linear parameter varying (LPV) control technique is proposed for the control of unmanned quadrotor helicopter (UQH), compensating the adverse effects of system variations, such as mass changes due to payload grasping, carrying, and dropping as well as battery voltage variations caused by battery drainage. The magnitudes of these variations, in this study, are assumed to be obtainable from the estimation scheme or priori knowable. Based on the information of these system variations, a linear parameter dependent state-feedback controller in a convex polytopic LPV representation is devised so that the corresponding adverse effects can be counteracted. The system parameters that vary with time are then specified as the design parameters for LPV controller, while the ultimate control law can be obtained online employing the well-established linear matrix inequality (LMI) conditions. Finally, both simulation and experimental validations are conducted to demonstrate the performance of the proposed control method on an UQH undergoing the changes of payload mass and battery voltage.