add vision biped paper

README.md

@@ -495,6 +495,7 @@
 
 - [Hybrid Stepping Motion Generation for Wheeled-Bipedal Robots Without Roll Joints on Legs](https://ieeexplore.ieee.org/abstract/document/10406411)
 - [Learning hybrid locomotion skills—Learn to exploit residual actions and modulate model-based gait control](https://www.frontiersin.org/articles/10.3389/frobt.2023.1004490/full)
+- [Learning Vision-Based Bipedal Locomotion for Challenging Terrain](https://arxiv.org/abs/2309.14594)
 - [Natural and Robust Walking using Reinforcement Learning without Demonstrations in High-Dimensional Musculoskeletal Models](https://arxiv.org/abs/2309.02976)
 - [Real-World Humanoid Locomotion with Reinforcement Learning](https://arxiv.org/abs/2303.03381)