The design of attitude controllers for UAVs is a challenging problem due to the high nonlinearities of the plant and its inherent instability. This work presents the development of a nonlinear controller based on Lyapunov theory in order to achieve a robust tracking for the orientation of a quadcopter. Based on a typical model, the inclusion of error integrals in the Lyapunov functions allow the UAV to achieve the desired set points without steady state error despite of changes in plant parameters and sensors noise. The results are compared in simulations to another nonlinear controller to show the robustness of the proposed strategy to disturbance in plant and outputs.