Recently, diffusion model shines as a promising backbone for the sequence modeling paradigm in offline reinforcement learning(RL). However, these works mostly lack the generalization ability across tasks with reward or dynamics change. To tackle this challenge, in this paper we propose a task-oriented conditioned diffusion planner for offline meta-RL(MetaDiffuser), which considers the generalization problem as conditional trajectory generation task with contextual representation. The key is to learn a context conditioned diffusion model which can generate task-oriented trajectories for planning across diverse tasks. To enhance the dynamics consistency of the generated trajectories while encouraging trajectories to achieve high returns, we further design a dual-guided module in the sampling process of the diffusion model. The proposed framework enjoys the robustness to the quality of collected warm-start data from the testing task and the flexibility to incorporate with different task representation method. The experiment results on MuJoCo benchmarks show that MetaDiffuser outperforms other strong offline meta-RL baselines, demonstrating the outstanding conditional generation ability of diffusion architecture.

本文提出了一种基于任务的条件扩散规划器(MetaDiffuser)来解决离线 meta-RL 中通用性问题，该规划器可以生成针对任务的轨迹以在各种任务间进行规划。实验结果表明 MetaDiffuser 能够表现出优异的生成轨迹能力，优于其他离线 meta-RL 基线模型。

MetaDiffuser：离线Meta-RL的扩散模型作为条件规划器