2025
Reinforcement Learning Agent for Multi-Objective Online Process Parameter Optimization of Manufacturing Processes
Akshay Paranjape, Nahid Quader, Lars Uhlmann, Benjamin Berkels, Dominik Wolfschläger, Robert H. Schmitt, Thomas Bergs
Applied Sciences (MDPI), 15(13), 7279, 2025
Manufacturing lines have to balance several conflicting goals at once, such as reducing scrap while keeping the process stable, and the right machine settings have to be chosen in real time while production is running. We frame this as a multi-objective reinforcement learning problem: an agent trained with Multi-Objective Maximum a Posteriori Optimization (MO-MPO) proposes process parameters online. The case study is pinion gear manufacturing, with a high-fidelity Simufact simulation used both to generate training data and to validate the agent. To check that the approach generalises, we also test it on open-source manufacturing datasets and synthetic data. A half-space analysis verifies that the agent’s solutions are Pareto-optimal, and the results show the method is feasible for real-time industrial use.
Abstract
Optimizing manufacturing processes to reduce scrap and enhance process stability presents significant challenges, particularly when multiple conflicting objectives must be addressed concurrently. As the number of objectives increases, the complexity of the optimization task escalates. This difficulty is further intensified in online optimization scenarios, where optimal parameter settings must be delivered in real time within active production environments. In this work, we propose a reinforcement learning-based framework for the multi-objective optimization of manufacturing parameters, demonstrated through a case study on pinion gear manufacturing. The framework utilizes the Multi-Objective Maximum a Posteriori Optimization (MO-MPO) algorithm to train a reinforcement learning agent. A high-fidelity simulation of the pinion manufacturing process is constructed in Simufact, serving both data generation and validation purposes. The agent’s performance is assessed using a hold-out test set along with additional simulations of the physical process. To ensure the generalizability of the approach, further validation is performed using open-source manufacturing datasets and synthetically generated data. The results demonstrate the feasibility of the proposed method for real-time industrial deployment. Moreover, Pareto-optimality is verified via half-space analysis, emphasizing the framework’s effectiveness in managing trade-offs among competing objectives.