Nonlinear and Linear PID Controllers-Based Hybrid Flight Control Strategy for a Quadcopter With Slung Load. - Abhishek Manalathody; Kishoor Santhana Krishnan; Jisnu Adindtra Subramanian; Sakthivel Thangavel; Jinraj V. Pushpangathan; Hariprasanth Paranjothy (IEEE Access, 2025)