Radu Stoican, Angelo Cangelosi, Thomas Weisswange, "MEWA: A Benchmark For Meta-Learning in Collaborative Working Agents", IEEE Symposium Series on Computational Intelligence (SSCI 2023), 2023.

Meta-reinforcement learning aims to overcome important limitations in reinforcement learning, like low sample efficiency and poor generalization, by creating agents that adapt to new tasks. The development of intelligent robots would benefit from such agents. Long-standing issues like data collection and generalization to real-world dynamic environments could be mitigated by sample-efficient adaptable algorithms. However, most such algorithms have only been proven to work in low-complexity environments. These provide no guarantee that a near-optimal global policy does not exist, which makes it difficult to evaluate adaptable policies. This hinders the in-depth analysis of an agent’s potential to adapt, while also introducing a gap between controlled experiments and real-world applications. We propose MEWA, a collection of task distributions used as a benchmark for adaptable agents. Our tasks contain a shared structure that an agent can leverage to learn the task-specific structure of new tasks. To ensure our environment is adaptive, we select some of the task parameters using the solution to a constrained optimization problem. Other parameters are randomized, allowing the creation of arbitrary task distributions. We evaluate three state-of-the-art meta-reinforcement learning algorithms on our benchmark, that were previously shown to adapt to new tasks with a simpler structure. Results show that the algorithms can reach meaningful performance on the task, but cannot yet fully adapt to the task-specific structure. We believe this benchmark will help identify some of the issues that hinder adaptability, ultimately aiding in the design of new algorithms, more suitable for real-world human-robot applications.