Thermoplastic composites are widely used in the manufacturing of composite components due to their fast molding speed and excellent mechanical properties. This paper proposes a robotic winding system based on the collaboration between a six-axis industrial robot and a positioner, aiming to achieve the automated winding of thermoplastic composites. The system integrates multi-physics control modules (tension, temperature, pressure) with an offline programming module, and combines the winding path generated by CADWIND to enable coordinated motion planning of the robot’s end-effector posture and the mandrel rotation angle. Traditional methods, when generating trajectories, assume a certain yarn suspension length, which may lead to the roller detaching from the mandrel and failure in molding. To address this issue, a geometry-based trajectory generation method is proposed to ensure constant contact between the roller and the mandrel. Experimental results demonstrate that the developed system can effectively complete winding tasks on complex surfaces, such as pressure vessel with elliptical domes, highlighting the potential of the system for automated thermoplastic composite winding applications.