Saved in:
Bibliographic Details
Main Authors: Liu, Bingyi, He, Jinbo, Shi, Haiyong, Wang, Enshu, Han, Weizhen, Hao, Jingxiang, Wang, Peixi, Zhang, Zhuangzhuang
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2601.05675
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915718723796992
author Liu, Bingyi
He, Jinbo
Shi, Haiyong
Wang, Enshu
Han, Weizhen
Hao, Jingxiang
Wang, Peixi
Zhang, Zhuangzhuang
author_facet Liu, Bingyi
He, Jinbo
Shi, Haiyong
Wang, Enshu
Han, Weizhen
Hao, Jingxiang
Wang, Peixi
Zhang, Zhuangzhuang
contents Hybrid action space, which combines discrete choices and continuous parameters, is prevalent in domains such as robot control and game AI. However, efficiently modeling and optimizing hybrid discrete-continuous action space remains a fundamental challenge, mainly due to limited policy expressiveness and poor scalability in high-dimensional settings. To address this challenge, we view the hybrid action space problem as a fully cooperative game and propose a \textbf{Cooperative Hybrid Diffusion Policies (CHDP)} framework to solve it. CHDP employs two cooperative agents that leverage a discrete and a continuous diffusion policy, respectively. The continuous policy is conditioned on the discrete action's representation, explicitly modeling the dependency between them. This cooperative design allows the diffusion policies to leverage their expressiveness to capture complex distributions in their respective action spaces. To mitigate the update conflicts arising from simultaneous policy updates in this cooperative setting, we employ a sequential update scheme that fosters co-adaptation. Moreover, to improve scalability when learning in high-dimensional discrete action space, we construct a codebook that embeds the action space into a low-dimensional latent space. This mapping enables the discrete policy to learn in a compact, structured space. Finally, we design a Q-function-based guidance mechanism to align the codebook's embeddings with the discrete policy's representation during training. On challenging hybrid action benchmarks, CHDP outperforms the state-of-the-art method by up to $19.3\%$ in success rate.
format Preprint
id arxiv_https___arxiv_org_abs_2601_05675
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle CHDP: Cooperative Hybrid Diffusion Policies for Reinforcement Learning in Parameterized Action Space
Liu, Bingyi
He, Jinbo
Shi, Haiyong
Wang, Enshu
Han, Weizhen
Hao, Jingxiang
Wang, Peixi
Zhang, Zhuangzhuang
Artificial Intelligence
Hybrid action space, which combines discrete choices and continuous parameters, is prevalent in domains such as robot control and game AI. However, efficiently modeling and optimizing hybrid discrete-continuous action space remains a fundamental challenge, mainly due to limited policy expressiveness and poor scalability in high-dimensional settings. To address this challenge, we view the hybrid action space problem as a fully cooperative game and propose a \textbf{Cooperative Hybrid Diffusion Policies (CHDP)} framework to solve it. CHDP employs two cooperative agents that leverage a discrete and a continuous diffusion policy, respectively. The continuous policy is conditioned on the discrete action's representation, explicitly modeling the dependency between them. This cooperative design allows the diffusion policies to leverage their expressiveness to capture complex distributions in their respective action spaces. To mitigate the update conflicts arising from simultaneous policy updates in this cooperative setting, we employ a sequential update scheme that fosters co-adaptation. Moreover, to improve scalability when learning in high-dimensional discrete action space, we construct a codebook that embeds the action space into a low-dimensional latent space. This mapping enables the discrete policy to learn in a compact, structured space. Finally, we design a Q-function-based guidance mechanism to align the codebook's embeddings with the discrete policy's representation during training. On challenging hybrid action benchmarks, CHDP outperforms the state-of-the-art method by up to $19.3\%$ in success rate.
title CHDP: Cooperative Hybrid Diffusion Policies for Reinforcement Learning in Parameterized Action Space
topic Artificial Intelligence
url https://arxiv.org/abs/2601.05675