This paper proposes a new methodology for motion planning in redundant robotic system for the high-speed fiber placement technology. The considered system is composed of a 6-axis industrial robot and a one-axis actuated positioner. Compared to the previous works assuming constant rate, the particularity of this work lies in the time-optimal motion coordination based on the combinatorial optimization and the polynomial approximation techniques. Advantages of the developed technique are confirmed by an application example that deals with a planar robotic system for fiber placement.