Vision based control of an autonomous blimp with actuator saturation using pulse-width modulation

This paper demonstrates an effective way to track any targeted object with unmanned aerial vehicle (UAV) by using Continuously Adaptive Mean Shift (Camshift) Algorithm, Proportional-Derivative (PD) controller and Pulse Width modulation (PWM). The approach proposed in this paper is applied to a blimp equipped with a Wireless video Camera and radio controlled propellers. When determining the model that best describes the behaviour of the blimp, it was found that a good approximation of the behaviour is accomplished by a model that includes saturations in velocity and actuation. The controller proposed is designed in two steps: first, one determines a PD controller that satisfies the specifications for the model without saturations. Then, PWM is used to address the effect of nonlinearities.