activity
20232025
collaborators

8 papers

cs.AI2025

Real-Time Diffusion Policies for Games: Enhancing Consistency Policies with Q-Ensembles

Ruoqi Zhang, Ziwei Luo, Jens Sjölund +3

Diffusion models have shown impressive performance in capturing complex and multi-modal action distributions for game agents, but their slow inference speed prevents practical depl…

eess.SY2025

Convergence in On-line Learning of Static and Dynamic Systems

Torbjörn Wigren, Ruoqi Zhang, Per Mattsson

The paper derives analytical expressions for the asymptotic average updating direction of the adaptive moment generation (ADAM) algorithm when applied to recursive identification o…

eess.SY2024

Safe Output Feedback Improvement with Baselines

Ruoqi Zhang, Per Mattsson, Dave Zachariah

In data-driven control design, an important problem is to deal with uncertainty due to limited and noisy data. One way to do this is to use a min-max approach, which aims to minimi…

cs.LG2024

Entropy-regularized Diffusion Policy with Q-Ensembles for Offline Reinforcement Learning

Ruoqi Zhang, Ziwei Luo, Jens Sjölund +2

This paper presents advanced techniques of training diffusion policies for offline reinforcement learning (RL). At the core is a mean-reverting stochastic differential equation (SD…

cs.LG2023

Risk-sensitive Actor-free Policy via Convex Optimization

Ruoqi Zhang, Jens Sjölund

Traditional reinforcement learning methods optimize agents without considering safety, potentially resulting in unintended consequences. In this paper, we propose an optimal actor-…

eess.SY2023

Aiding reinforcement learning for set point control

Ruoqi Zhang, Per Mattsson, Torbjörn Wigren

While reinforcement learning has made great improvements, state-of-the-art algorithms can still struggle with seemingly simple set-point feedback control problems. One reason for t…

eess.SY2023

Robust nonlinear set-point control with reinforcement learning

Ruoqi Zhang, Per Mattsson, Torbjörn Wigren

There has recently been an increased interest in reinforcement learning for nonlinear control problems. However standard reinforcement learning algorithms can often struggle even o…

eess.SY2023

Observer-Feedback-Feedforward Controller Structures in Reinforcement Learning

Ruoqi Zhang, Per Mattson, Torbjörn Wigren

The paper proposes the use of structured neural networks for reinforcement learning based nonlinear adaptive control. The focus is on partially observable systems, with separate ne…