What is GRAS?

GRAS is a simulator for mechanical robots. The GRAS program is written in the Java language for maximum portability and ease of use. The GRAS program is free for all uses. Click on the image to the right for a screen shot of GRAS in action.

What does GRAS do?

GRAS is designed as an extensible framework for robotics simulation. As such, it will continue to grow and change incorporating new ideas all the time. At the present, the major feature set of GRAS includes:
• Robot simulated is presented realtime as a 3D solid model
  
• Arbitrary robot configurations and geometry are possible, by specifying an appropriate robot description file.
  
• Full implementation of Direct Kinematics on arbitrary robot models
  
• Inverse Kinematics is available if a InverseSolver class is available for the specific robot.
  
• Multiple motion models are possible, providing different ways of interpolating joint angles.
  
• The Java language provides complete portability to all systems that support the Java JDK 1.0 system.
  

What is GRAS designed for?

GRAS is designed as a teaching tool for robotics. Robotics is a broad area of interest to many people, but because of the prohibitive costs associated, purchasing a robot is not always economically feasable. In cases where a robot is owned, a software simulator can still help prototype experiments and allow multiple people work with a robot at the same time.

How do I try GRAS out?

Click on one of the buttons to the right to see an example of GRAS simulating a robot scene. The two main characters in the scenes are the PUMA-560 robot and the Pegasus robot, but there are other objects thrown in as well. If you would like to take a look at the scene/object description format, take a look here: Example Files.

Note that the last two examples are best viewed in Z-Buffer mode. To enable this, click on "View" then "Configure" then "Z-Buffer Rendering".

Who created GRAS?

Chris Lattner designed and implemented the GRAS system from the Spring of 1998 until whenever it was updated last (currently May 2000). If you would like to get in touch, feel free to email him.

Where can I get more information about GRAS?

I published a paper about GRAS at a conference way back when... if you'd like to read it, it talks about the robotics system, the graphics system, and how Java turned out to be useful. It is named Developing a Graphical Robotics Simulator.

How do I get the source for GRAS?

Visit the Download Page!

GRAS has recently (as of Nov 20, 2000) been open sourced! Download, play with, and let me know how it works for you!