In this paper, a "risk set" is introduced within the safe set of a safety-critical nonlinear tracking controller to enhance performance while avoiding overly conservative behavior. Utilizing a barrier function approach within a quadratic cost framework, this set is incorporated into the State-Dependent Riccati Equation (SDRE) for the inner control loop of Uncrewed Aerial Vehicles (UAVs), ensuring safe flight control of quadrotors. Additionally, a sliding mode controller is designed for the outer loop to generate the desired trajectory for the inner loop. The risk set further enables systematic switching of weighting adjustments in the nonlinear tracking SDRE controller to balance system performance and safety requirements. This approach is compared to that for scenarios without switching weighting adjustments, and the results demonstrate that the proposed controller satisfies safety constraints while delivering improved performance.
