Heterogeneous Multi-Agent Reinforcement Learning for Zero-Shot Scalable Collaboration
Xudong Guo, Daming Shi, Junjie Yu, Wenhui Fan
TL;DR
SHPPO introduces a scalable, heterogeneous MARL framework that embeds agent-specific policy variance via a latent network and a per-agent heterogeneous layer, enabling zero-shot scalability to unseen team sizes. A centralized InferenceNet guides latent learning, while losses promote identifiable and diverse latent representations, yielding adaptive behavior without architecture blow-up. Evaluations on SMAC and GRF demonstrate competitive performance to heterogeneous baselines on original tasks and superior zero-shot transfer to varying populations, with insights into latent space correspondences to team strategies. This approach offers practical scalability for real-world multi-agent systems by decoupling heterogeneity from base parameter sharing and enabling flexible role assignment across dynamic team sizes.
Abstract
The emergence of multi-agent reinforcement learning (MARL) is significantly transforming various fields like autonomous vehicle networks. However, real-world multi-agent systems typically contain multiple roles, and the scale of these systems dynamically fluctuates. Consequently, in order to achieve zero-shot scalable collaboration, it is essential that strategies for different roles can be updated flexibly according to the scales, which is still a challenge for current MARL frameworks. To address this, we propose a novel MARL framework named Scalable and Heterogeneous Proximal Policy Optimization (SHPPO), integrating heterogeneity into parameter-shared PPO-based MARL networks. We first leverage a latent network to learn strategy patterns for each agent adaptively. Second, we introduce a heterogeneous layer to be inserted into decision-making networks, whose parameters are specifically generated by the learned latent variables. Our approach is scalable as all the parameters are shared except for the heterogeneous layer, and gains both inter-individual and temporal heterogeneity, allowing SHPPO to adapt effectively to varying scales. SHPPO exhibits superior performance in classic MARL environments like Starcraft Multi-Agent Challenge (SMAC) and Google Research Football (GRF), showcasing enhanced zero-shot scalability, and offering insights into the learned latent variables' impact on team performance by visualization.
