Full disclosure: I'm Nate Koenig, co-founder.

Normally I keep to side lines and let the internet buzz take care of itself. However, I was disheartened to see the most highly ranked comment be so negative about a free project designed to improve not only robotics research, but also disaster response robots.

Animats does have one valid point. Gazebo has been buggy, in the past. It was also just a side project with one developer and no funding until a few years ago when Willow Garage brought Gazebo under its roof. Gazebo has now matured beyond a research project into a robust application with a growing community of users and developers.

It's been particularly exciting to have simulation move into the cloud. The cost and time required to start a complex simulation has been greatly reduced. Educators, hobbyists, and researchers now have a great tool for a wide variety of uses. Cloud computing is designed for large data sets and strict performance requirements. Simulation needs both of these.

ODE is currently the primary physics engine in Gazebo, with Bullet integration almost complete and SimBody and RTQL8 within a year. It deserves to be mentioned that ODE and Bullet both use a maximal coordinate solvers. This means they effectively produce the same result. Many games use engines similar or identical to ODE and Bullet. The key difference is how they are used. Gazebo optimizes ODE and Bullet for robot simulation. This means physics run slower, but we get out less residual error. There are other tricks game engines play that a simulator can't, but at the end of the day we are all just solving the equations of motion.

Over the next few years expect to see great things from Gazebo, including scripting interfaces, plotting utilities, robot modeling widgets, physics auto-tuning, many more robots and environments, vehicle suspension models, improved friction modeling, a sensor noise model pipeline, and deformable objects.

Most importantly, I want to thank everyone who have used and contributed to Gazebo (especially all the VRC teams who toiled through countless hours to produce very impressive results of Atlas completing complex tasks). Good luck to everyone continuing on in the DRC!!

I love big data, especially when it helps people.

There are a lot of great features in Gazebo these days. It's great that DARPA is funding an open source project, especially one that is designed to live long after the DRC ends.