The growing demand for individualized products is becoming more and more significant and leads to a reduction in batch sizes. In particular, the production of multi-material components for lightweight design presents new challenges to the manufacturing process. This is evident when it comes to the production of individual parts, as today’s processes are characterized by high tool costs and manual operations. The described challenge can be overcome by a robot-based manufacturing cell allowing the use of a novel, modular process chain in which metal parts are mechanically pre-treated, subsequently completed by additive plastic application, and afterwards finalized in a machining step to achieve the required surface qualities and geometries. In order to realize the novel process chain, robot-based solutions for free-form metal sheet processing, increased interlayer bonding strength of plastic, and multi-material machining with integrated chip extraction have to be found. Therefore, this paper presents the first approach of a robot-guided surface structuring end-effector and a concept for a direct extraction hood, which is able to be adapted specifically to the movement of the robot and the part surface, so free-form surfaces can be machined. Based on this, first experimental studies for increasing the interlayer bonding strength of plastic were carried out using an extruder set up to applicate thermoplastics onto metal at high deposition rates. To define the positioning accuracy for a robot-guided structuring process, different point to point movements have been investigated.

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The production of individual work pieces in small to medium batch sizes requires an adaptation of the manufacturing strategy. Particularly, the manufacturing of multi-material components out of metal and plastic is characterized by high production costs as well as high production times. To resolve this challenge, a new, modular process chain for the production of these structures in a single manufacturing cell was developed. In this cell, a robot manufactures multi-material components with multiple end-effectors in several successive process steps. In the first step, interlocking structures are manufactured on a metal part by a surface structuring tool. Afterwards, an extruder is used to add a thermoplastic onto the structured metal part. Due to mechanical interlocking effects, the applied thermoplastic shows improved adhesion behavior. A study was conducted to analyze the achievable joint strength of the additive material application onto the structured metal samples. Investigations to determine the achievable manufacturing quality of a robot guided milling process for multi-material parts have been carried out. A recently developed suction hood is used to capture the metal and plastic chips. In this paper, the results regarding the efficiency of the individual end-effectors, including the extraction hood, are presented and it is demonstrated how they interact within the robot-based process chain.