Output feedback attitude control for rigid spacecraft under attitude constraints

An output feedback control law is proposed in this paper for spacecraft attitude reorientation task. Although maneuver has been widely investigated and obtained significant results, it still challenging when considering pointing constraints lacking the information of angular velocity. Firstly, potential function introduced to tackle constraints. Then, by jointly designing sign function, anti-unwinding performance can also be achieved. Furthermore, relevant velocity utilizing first-order passive filter with error quaternion. Moreover, properly selecting candidate Lyapunov feasibility rigorously proved under law, while stability system guaranteed without signal inertia matrix. A numerical example carried out demonstrate effectiveness method.