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README.md

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 [![Docs](https://docs.rs/peng_quad/badge.svg)](https://docs.rs/peng_quad/latest/peng_quad/)
 [![CI](https://github.com/makeecat/Peng/actions/workflows/CI.yml/badge.svg)](https://github.com/makeecat/Peng/actions/workflows/CI.yml)
 [![dependency status](https://deps.rs/repo/github/makeecat/peng/status.svg)](https://deps.rs/repo/github/makeecat/peng)
+[![Gitter](https://img.shields.io/gitter/room/peng/peng)](https://app.gitter.im/#/room/#peng:gitter.im)
 ## What is Peng
 Peng is a minimal Rust-based quadrotor simulation pipeline. It includes a simulator, controller, and planner, providing a basic framework for simulating quadrotor dynamics and control.
 ![demo](assets/Peng_demo.gif)