SkillX: Unified Multi-Skill Policy Learning for Humanoid Soccer

Zhangchen Ye1* Enxuan Ruan1* Yifei Bao1*
Runhan Huang2 Jiankun Yang1 Jiakang Jin1 Yixiao Huo1
Pengyuan Wang1 Yinan Han1 Huaxing Huang1 Wenhao Cui1

Abstract

Humanoid soccer is a challenging testbed for dynamic whole-body control, requiring robots to coordinate balance, locomotion, object interaction, and skill switching over long horizons. Existing humanoid sports methods often rely on task-specific multi-stage pipelines, making it difficult to jointly learn and compose multiple object-interactive skills within a single deployable policy. To address this, we present SkillX, a unified reinforcement learning framework that learns and composes multiple atomic soccer skills through a single command-conditioned policy. SkillX integrates three core designs: skill-specific adversarial motion priors, skill-specific critics, and an object-aware temporal encoder, enabling the robot to execute atomic skills and transition among them such as dribbling, trapping, and shooting. Experiments in simulation and on a real Noetix E1 humanoid demonstrate robust multi-skill execution, long-horizon skill composition, and successful sim-to-real deployment.

Method Overview

SkillX keeps one command-conditioned actor, while skill-specialized training signals preserve distinct motion styles and support reliable transitions.

Skill-Specific Adversarial Motion Priors

Provide style rewards for heterogeneous skills.

Skill-Specific Critics

Estimate skill-dependent values.

Object-Aware Temporal Encoder

Aggregates compact history features.

SkillX method pipeline showing skill-specific motion priors, skill-specific critics, and an object-aware temporal encoder

Real-World Experiments