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The excellent material properties of fibre reinforced composites make them especially attractive for applications in the aerospace and automotive industries. Traditional methods of manufacturing composite structures have proven to be labour intensive and time‐consuming. Robotic fibre placement for fabrication of composite components has been proposed. This approach greatly reduces production cost and time. This paper briefly presents the overall strategy for the establishment of a robotic fibre placement facility. The methodology for development of process planning and programming, simulation, program generator and control is described. In addition, the algorithms for automatic fibre path generation for open and closed surfaces will also be discussed, as well as the control system architecture for the process.

SummaryIn this paper, a lumped parameter model of a robotic fibre placement system consisting of a Motoman SK-120 robot, a force/torque sensor, a pneumatic actuator and a stiff workpiece holder is developed and experimentally verified for the purpose of predicting and characterising the dynamic behaviour of the fibre placement system. Special attention has been given to the dynamics of the actuator which is represented as a mass confined to move between two non-linear springs and dampers. The overall model containing manipulator, force sensor, pneumatic actuator and the workpiece holder dynamics is of the tenth order. Step response experiments were conducted to verify the model and to determine the approximate values of the parameters in the mathematical model. The results prove that the established model is accurate enough to explain the dynamic behaviour of the fibre placement system and it can be employed to quantify the influence of the dynamics of the pneumatic actuator on the constant force-based fibre placement. The well-known fact that the dynamics of the pneumatic actuator varies with the piston position has also been experimentally demonstrated.

Laser interferometry‐based sensing (LIS) technique has been proposed and established recently to track and perform dynamic measurements on a moving end‐effector of a robot manipulator. In this paper, a technique using LIS system to perform guidance of a manipulator is proposed. The LIS system is used as a sensor to guide the end‐effector of a robot manipulator. This is to be accomplished through the implementation of guidance error determination and compensation, and path generation in the control algorithm. This technique can be used to accurately guide the manipulator’s end‐effector to a specified location or along a specified path with a high level of accuracy. The structure and various components within the system and the control strategy are also presented.