AdaptDiffuser: Diffusion Models as Adaptive Self-evolving Planners
This addresses the problem of improving planning and generalization in offline reinforcement learning for researchers and practitioners, though it appears incremental as it builds on existing diffusion model methods.
The paper tackles the problem of diffusion models having limited diversity in training data for offline reinforcement learning planning, introducing AdaptDiffuser which self-evolves to improve the diffusion model and adapt to unseen tasks. The result shows AdaptDiffuser outperforms previous methods by 20.8% on Maze2D and 7.5% on MuJoCo locomotion, and adapts to new tasks like KUKA pick-and-place by 27.9% without extra expert data.
Diffusion models have demonstrated their powerful generative capability in many tasks, with great potential to serve as a paradigm for offline reinforcement learning. However, the quality of the diffusion model is limited by the insufficient diversity of training data, which hinders the performance of planning and the generalizability to new tasks. This paper introduces AdaptDiffuser, an evolutionary planning method with diffusion that can self-evolve to improve the diffusion model hence a better planner, not only for seen tasks but can also adapt to unseen tasks. AdaptDiffuser enables the generation of rich synthetic expert data for goal-conditioned tasks using guidance from reward gradients. It then selects high-quality data via a discriminator to finetune the diffusion model, which improves the generalization ability to unseen tasks. Empirical experiments on two benchmark environments and two carefully designed unseen tasks in KUKA industrial robot arm and Maze2D environments demonstrate the effectiveness of AdaptDiffuser. For example, AdaptDiffuser not only outperforms the previous art Diffuser by 20.8% on Maze2D and 7.5% on MuJoCo locomotion, but also adapts better to new tasks, e.g., KUKA pick-and-place, by 27.9% without requiring additional expert data. More visualization results and demo videos could be found on our project page.