Willow Garage is using software from the Player Project to develop the application programming stack for the PR2 robot. All three components of the project -- Player, Stage, and Gazebo -- have been adapted for use from within the ROS platform, creating a strong synergy between the two robot software platforms and enabling ROS software developers to access and reuse the wealth of drivers, algorithms and simulation environments that the Player Project community has developed.
About the Player Project
The Player Project creates Free Software that enables research in robot and sensor systems. It consists of Player, a robot interface, Stage, a two-dimensional robot simulator, and Gazebo, a three-dimensional robot simulator.
Player provides a network interface to a variety of robot and sensor hardware. Player's client/server model allows robot control programs to be written in any programming language and to run on any computer with a network connection to the robot.
Stage simulates a population of mobile robots moving in and sensing a two-dimensional bitmapped environment. Various sensor models are provided, including sonar, scanning laser rangefinder, pan-tilt-zoom camera with color blob detection and odometry. Gazebo is a multi-robot simulator for outdoor environments. Like Stage, it is capable of simulating a population of robots, sensors and objects, but does so in a three-dimensional world. It generates both realistic sensor feedback and physically plausible interactions between objects (it includes an accurate simulation of rigid-body physics).
Player is developed by an international team of robotics researchers and used at labs around the world. Willow Garage is supporting general maintenance of the project, as well as ROS-specific enhancements. Released under the GPL and/or LGPL, all code from the Player project is free to use, distribute and modify.
As is the case with many open source projects, Player grew out of a need for an alternative to existing closed source software. In the summer of 2000, Brian Gerkey, Richard Vaughan, and Kasper Stoy became sufficiently frustrated with commercial robot interface software that they couldn't inspect, modify, or fix, to embark on what seemed like a simple project: build a networked server that provides a convenient interface to the Pioneer mobile robot and its sensors, and build a simulator that supports the same interface. The results were, respectively, Player and Stage, which were first distributed directly from the USC Robotics Lab website, before migrating to SourceForge, circa January 2001. Since that time, the Player Project has grown enormously, and Player software is probably the most widely used system of its kind in academic, government, and industrial labs.