Reinforcement Learning Researcher

Reliable learning
with theoretical guarantees.

I develop simple, principled learning objectives for reinforcement learning and the post-training of large foundation models.

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Education & Experience

Pushing the Frontiers of Learning

My path spans foundational reinforcement learning and large foundation model post-training.

Research Internship

Post-training & On-Policy Distillation

LLM Startup

Foundation Models
Research Team

Foundational Reinforcement Learning Team

Hunyuan Qingyun Project

Reinforcement Learning
Research Experience

Research Assistant

The Hong Kong University of Science and Technology (Guangzhou)

Research
Education

Undergraduate Student

Chongqing Normal University

Undergraduate
First page of the Trust Region Policy Distillation paper
PDF ↗

01 / 2026

Trust Region Policy Distillation

TOP-D

Stable on-policy distillation through a dynamically constructed proximal teacher.

TOP-D converts the unbounded learning signal of standard OPD into a smooth, lower-bounded reward, with formal convergence and monotonic improvement guarantees.

The Impact of TOP-D

Want to make history? I'm waiting for you.

Start a collaboration↗
First page of the official Simple Policy Optimization paper
PDF ↗

02 / ICML 2025

Simple Policy Optimization

SPO

A first-order policy optimization objective that preserves corrective gradients beyond the trust region.

By slightly modifying PPO's policy loss, SPO combines PPO's implementation simplicity with TRPO's strong theoretical guarantees, while retaining stable first-order optimization for deep policy networks.

From objective to embodiment

The Impact of SPO

Two independent robotics projects use SPO-style constraints to keep policy updates corrective and stable.

01Physical Intelligence · 2025

π*0.6: a VLA that Learns from Experience

Physical Intelligence. The technical report implements a DPPO/FPO variant with an alternative PPO constraint following SPO for real-robot reinforcement learning.

Vision-Language-ActionReal-robot RLSPO constraint
Technical report↗
02Amazon FAR · UC Berkeley · 2026

Flow Policy Gradients for Robot Control

Brent Yi, Hongsuk Choi, et al. FPO++ uses an asymmetric trust region: PPO for positive advantages and SPO for negative advantages.

Flow policySim-to-realHumanoid control
Paper↗
π*0.6 · Official Real-Robot demoLearning from real-world experience
Physical Intelligence · π*0.6

Learning from real-world experience

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FPO++ · Official Sim-to-Real demosThree physical humanoid behaviors

Official demo excerpts. Click any video to open its original project page.

Zhengpeng Xie

Building the foundations for a future of reliable, self-improving intelligence.