Reinforcement learning

Disassembly line optimization with reinforcement learning

As the environmental aspects become increasingly important, the disassembly problems have become the researcher’s focus. Multiple criteria do not enable finding a general optimization method for the topic, but some heuristics and classical formulations provide effective solutions. By highlighting that disassembly problems are not the straight inverses of assembly problems and the conditions are not standard, disassembly optimization solutions require human control and supervision. Considering that Reinforcement learning (RL) methods can successfully solve complex optimization problems, we developed an RL-based solution for a fully formalized disassembly problem. There were known successful implementations of RL-based optimizers. But we integrated a novel heuristic to target a dynamically pre-filtered action space for the RL agent (DLOPTRL algorithm) and hence significantly raise the efficiency of the learning path. Our algorithm belongs to the Heuristically Accelerated Reinforcement Learning (HARL) method class. We demonstrated its applicability in two use cases, but our approach can also be easily adapted for other problem types. Our article gives a detailed overview of disassembly problems and their formulation, the general RL framework and especially Q-learning techniques, and a perfect example of extending RL learning with a built-in heuristic.


Post Date: 11 March 2024

Multi-agent reinforcement learning-based exploration of optimal operation strategies of semi-batch reactors

The operation of semi-batch reactors requires caution because the feeding reagents can accumulate, leading to hazardous situations due to the loss of control ability. This work aims to develop a method that explores the optimal operational strategy of semi-batch reactors. Since reinforcement learning (RL) is an efficient tool to find optimal strategies, we tested the applicability of this concept. We developed a problem-specific RL-based solution for the optimal control of semi-batch reactors in different operation phases. The RL-controller varies the feeding rate in the feeding phase directly, while in the mixing phase, it works as a master in a cascade control structure. The RL-controllers were trained with different neural network architectures to define the most suitable one. The developed RL-based controllers worked very well and were able to keep the temperature at the desired setpoint in the investigated system. The results confirm the benefit of the proposed problem-specific RL-controller. 



The Applicability of Reinforcement Learning Methods in the Development of Industry 4.0 Applications

Reinforcement learning (RL) methods can successfully solve complex optimization problems. Our article gives a systematic overview of major types of RL methods, their applications at the field of Industry 4.0 solutions, and it provides methodological guidelines to determine the right approach that can be fitted better to the different problems, and moreover, it can be a point of reference for R&D projects and further researches.