Robotic Kinematic Modeling and Deformation of Composite Laminates via Automated Fiber Placement Manufacturing

Robotic arm-assisted Automated Fiber Placement (AFP) for advanced composite structure manufacturing typically relies on position-based kinematic motion to plan placement trajectories. After each ply is laid, the placement head is incrementally shifted upward by the prepreg thickness to place the next layer. However, uncured elastic prepreg tapes are prone to deformation, and non-uniform tooling surfaces can lead to variations in compaction pressure across the laid layers. With the accumulation of layers, such variations become more pronounced because of the variation in stiffness of placed materials, and maintaining a consistent force using a position-based approach becomes difficult. The inconsistent pressure often causes reduced tackiness at the interface between the tool surface and materials and plies, which causes the potential wrinkling, twisting, or shifting of the material during composite manufacturing. This paper proposes studying force control to maintain a consistent force applied to the material during material placement. To accurately represent real manufacturing conditions and design a force control approach during the fiber placement process, a Collaborative Robotic Automated Fiber Placement Technology (CRAFT) system developed at Oklahoma State University was employed. The system integrates a force–torque sensor, used for monitoring, and a micro laser scanner to quantify the deformation in the width and thickness of the deposited tapes. This paper investigates the uniform and non-uniform compaction forces applied during single-tow deposition using the CRAFT system, and the experimental results demonstrated a moderate increase in deformation on the deposited tape under controlled force conditions. Establishing the correlation between the robotic kinematic motion and the resulting material deformation facilitates the implementation of adaptive force control, thereby ensuring adequate tackiness, minimizing material overspreading, and ultimately improving the consistency and overall structural quality of AFP-based composite manufacturing.