# NVIDIA PhysX

Modeling digital twins of factories, cities, or entire worlds involves complex simulations that must accurately replicate the physical behavior of objects and systems, which are foundational in building [physical AI](https://www.nvidia.com/en-us/glossary/generative-physical-ai/) for powering the next generation of autonomous systems.

NVIDIA PhysX® is a powerful, open-source multi-physics SDK that provides scalable simulation and modeling capabilities for robotics and autonomous vehicle applications.

[Get PhysX in Omniverse](https://developer.nvidia.com/omniverse) [Get PhysX Source on GitHub](https://github.com/NVIDIA-Omniverse/PhysX) [Documentation](https://docs.omniverse.nvidia.com/extensions/latest/ext_physics.html#overview)

PhysX based simulation of robots screwing nuts onto bolts, in Omniverse.

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## Key Benefits of PhysX

### Open-Source

PhysX is fully open-source, enabling free use and sharing of your work with other developers, as well as contributing your innovative developments back to the community.

### Unified

Model FEM soft body, cloth, particles, and fluid simulation with two-way coupled interactions under a unified solver framework.

### Scalable

Runs on various platforms, from mobile CPUs to high-end GPUs, with a GPU API supporting end-to-end reinforcement learning via NVIDIA Isaac™ Lab.

### Accurate

Enhanced simulation stability with robust collision detection, stacking, and joints, while also supporting momentum conservation and gyroscopic forces.

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## PhysX Features

### Rigid Body Dynamics

Analyze multi-body dynamics under external forces like gravity. PhysX offers scalable rigid-body simulation for CPU and GPU, with proven industry performance.

### Scene Query

Conduct spatial queries in simulated environments using the PhysX raycast, overlap, and sweep functions with customizable filtering.

### Joints

Utilize a suite of common built-in joint types and support custom joints in PhysX through a flexible callback mechanism.

### Reduced Coordinate Articulations

Reduced coordinate articulations provide a linear-time, guaranteed joint-error-free simulation of a tree of rigid bodies.

### Vehicle Dynamics

Study the movement of multi-body interactions under external forces, such as gravity. PhysX provides industry-proven scalable rigid body simulation on both CPU and GPU.

### Character Controllers

The kinematic character controller in PhysX permits an avatar to navigate a simulated world and supports both static and dynamically simulated bodies.

### Soft Body Dynamics

Finite Element Method (FEM) simulation of soft bodies allows for accurate and efficient models of elastic deformable bodies.

### SDF Colliders

A new Signed Distance Field based collision representation allows PhysX to simulate non-convex shapes like gears and cams without convex decomposition.

### Position-Based Dynamics

Position-Based Dynamics provide a flexible framework for simulating a wide range of phenomena including liquids, granular materials, cloth, rigid bodies, deformable bodies, and more.

### Custom Geometry

Utilize a wide range of built-in geometries and a flexible callback mechanism to allow custom geometry types into the simulation.

### Fracture & Destruction

Blast, available in PhysX, is a destruction and fracture library designed for performance, scalability, and flexibility.

### Smoke & Fire

Flow enables realistic combustible fluid, smoke, and fire simulations. Flow is part of the PhysX SDK.

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## PhysX Implementation

|  | CPUs | NVIDIA GPUs |
| --- | --- | --- |
| Character Controllers |  |  |
| Custom Geometries |  |  |
| Fracture and Destruction - PhysX Blast |  |  |
| Joints |  |  |
| PBD (liquid/cloth/inflatable/shape matching) |  |  |
| Reduced Coordinate Articulations |  |  |
| Rigid Body Dynamics |  |  |
| Scene Queries |  |  |
| Smoke and Fire - PhysX Flow |  |  |
| Soft Body Dynamics (Finite Element Method) |  |  |
| Vehicle Dynamics |  |  |

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## PhysX in NVIDIA Omniverse

PhysX is the primary physics engine of [NVIDIA Omniverse™](https://developer.nvidia.com/omniverse), a platform of APIs and SDKs for building complex 3D and industrial digitalization workflows based on [OpenUSD](https://www.nvidia.com/en-us/omniverse/usd/). NVIDIA [Isaac Sim](https://developer.nvidia.com/isaac/sim) ™ and [Isaac Lab](https://isaac-sim.github.io/IsaacLab/) are two robotics reference applications built on Omniverse, which enable developers to build physical AI to power next-generation robots.