Charles Xu

I am currently a PhD student at UC Berkeley, advised by professor Sergey Levine. I recently interned at Physical Intelligence, where I built a system for real-world online RL with VLA's. Before this, I finished my undergrad at UC Berkeley in EECS in May 2024, where I also conducted research with professor Sergey Levine. I've also had the pleasure of working with Stefan Schaal from Intrinsic. My research interest is learning from real-world experience through on-robot online reinforcement learning for scalable and deployable robot systems.

xuc [at] berkeley [dot] edu  /  GitHub  /  Google Scholar  

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Research

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Test-Time Gradient Guidance of Flow Policies in Reinforcement Learning


Zhiyuan Zhou, Andy Peng, Charles Xu, Qiyang Li, Jost Tobias Springenberg, Kevin Frans, Sergey Levine
Conference on Neural Information Processing Systems (NeurIPS), 2026
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π0.7: a Steerable Model with Emergent Capabilities


Physical Intelligence Team
Conference on Robot Learning (CoRL), 2026, Oral (top 1%)
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RL Token: Bootstrapping Online RL with Vision-Language-Action Models


Charles Xu, Jost Tobias Springenberg, Michael Equi, Ali Amin, Adnan Esmail, Sergey Levine, Liyiming Ke
Conference on Robot Learning (CoRL), 2026, Oral (top 1%)
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RLDG: Robotic Generalist Policy Distillation via Reinforcement Learning


Charles Xu, Qiyang Li, Jianlan Luo, Sergey Levine
Robotics: Science and Systems (RSS), 2025
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Precise and Dexterous Robotic Manipulation via Human-in-the-Loop Reinforcement Learning


Jianlan Luo†, Charles Xu†, Jeffrey Wu, Sergey Levine
Science Robotics, 2025
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Octo: An Open-Source Generalist Robot Policy


Dibya Ghosh*, Homer Walke*, Karl Pertsch*, Kevin Black*, Oier Mees*, Sudeep Dasari, Joey Hejna, Tobias Kreiman, Charles Xu, Jianlan Luo, You Liang Tan, Dorsa Sadigh, Chelsea Finn, Sergey Levine
Robotics: Science and Systems (RSS), 2024
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SERL: A Software Suite for Sample-Efficient Robotic Reinforcement Learning


Jianlan Luo*, Zheyuan Hu*, Charles Xu, Siri Gadipudi, Archit Sharma, Rehaan Ahmad, Stefan Schaal, Chelsea Finn, Abhishek Gupta, Sergey Levine
International Conference on Robotics and Automation (ICRA), 2024
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Open X-Embodiment: Robotic Learning Datasets and RT-X Models


Open X-Embodiment Collaboration
International Conference on Robotics and Automation (ICRA), 2024, Best Paper Award
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FMB: A Functional Manipulation Benchmark for Generalizable Robotic Learning


Jianlan Luo*, Charles Xu*, Fangchen Liu, Liam Tan, Zipeng Lin, Jeffrey Wu, Pieter Abbeel, Sergey Levine
The International Journal of Robotics Research (IJRR)
website / paper / video / code / data

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Multi-Stage Cable Routing through Hierarchical Imitation Learning


Jianlan Luo*, Charles Xu*, Xinyang Geng, Gilbert Feng, Kuan Fang, Liam Tan, Stefan Schaal, Sergey Levine
Transactions on Robotics (T-RO), 2024
website / paper / video / code / data




Teaching

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EECS C106A/206A: Introduction to Robotics


Lab Assistant: Fall 2023

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CS 189: Introduction to Machine Learning


Tutor: Spring 2023





Design and source code from Jon Barron's website