ExtendSim tools provide precise, proven toolsets so you can build powerful simulation models. ExtendSim can minimize risk and help you realize your potential and your goals.

ExtendSim simulation software and technologies have set the standard for simulation for more than three decades. Maintaining its goal to develop and support leading edge, innovative, dynamic modeling tools which can be used in virtually any field, it has become a leader in the industry...backed by years of proven results by tens of thousands of ExtendSim users.

The Birth of ExtendSim

Our commitment to innovation is as strong today as it was in the early days of the space race. At that time, ExtendSim architect Bob Diamond was attending the Polytechnic Institute of Brooklyn when the head of the Electronics Engineering department told him that a new department was being formed... a combination of mathematics, computers, physics and engineering. Being into math, and curious about the large IBM mainframe lurking down the hall, he immediately joined and became a constant presence in the computer center.

The bug bit hard, and he began to realize that he could use computers to duplicate the laboratory experiments in class so well, that he never really did the experiments, he just simulated them on the computer. Eventually, NASA approached him and asked if he could develop a simulation of their new liquid fuel booster for something called Project Apollo. He created the Rocket-Drop simulation, a monstrously large program that only had one function: follow the path of a single droplet of fuel, from the shower heads (as the fuel sprayers at the top of the engine were called) to the rocket engine exhaust, via subsonic, supersonic, and hypersonic flow.

Then, it hit him that simulation was inaccessible except to the select few who had the resources to put together an entire system dedicated to one function. A generalized simulation application would be a great and useful thing, if one could find the computer that was both powerful enough and widespread enough to support it. This was 1965, and Seymour Cray was still building his super fast (at the time!) computers by hand and graphic user interfaces were still decades in the future.

When he saw the graphical user interfaces (GUIs) on the Mac OS and Windows machines, he realized that he could use these tools to fulfill that long awaited dream. ExtendSim is built upon those roots.

Imagine That Inc. is Launched

Imagine That Inc. was founded in 1987 to develop and market Extend and its successor ExtendSim, the first simulation applications allowing users of any discipline to use simulation and to develop their own libraries of customized simulation tools. In 2024, the ExtendSim family of simulation tools was acquired by ANDRITZ Inc. - continuing the ExtendSim legacy.

Since its formation, the ExtendSim Team has been dedicated to bringing the art, science, and fun of simulation to the desktop, in a form digestible and accessible by everyone. Extend was the first user-extendible simulation package meeting those expectations.

ExtendSim Innovations

The Rocket-Drop Simulation was just the beginning. From the earliest days, the ExtendSim Team embraced its role as industry visionaries and leaders, continuing to solve previously insurmountable problems.

Extend was the first powerful, low cost, personal computer based simulation program developed specifically for a windowing environment.

Other trend-setting firsts followed, including:

  • hierarchical modeling capability
  • library-based modeling
  • message-based architecture
  • open source optimizer
  • built-in databases
  • inventor of discrete rate technology
  • integration with reliability block diagramming tool
  • available modules developed by third parties
  • drag-and-drop user interface
  • the first simulation package < $1,000

That vision continues today with trend-setting development in the areas of user interface design, simulation modeling flexibility, and ActiveX integration. Please see the complete History of ExtendSim for other firsts.

Customer Driven

Our customers span a range of industries and disciplines facing the challenge of adapting to new challenges by identifying solutions that will help lead to tomorrow's successes for their organizations. Around the world, the pace of technology adoption and change is phenomenal. We are committed to delivering the tools and technologies that simulationists need today, while providing next-generation solutions to respond to future opportunities.

Just look at who's using ExtendSim, where those companies are today, and where they'll be tomorrow. ExtendSim customers are acquiring a better understanding of the way things work, gaining the competitive edge, and improving their processes by quantum leaps.

ExtendSim is in use by over 10,000 businesses, universities, and government organizations worldwide, including: Clorox, Procter & Gamble, Boeing, Kaiser Permanente, Eli Lilly, ITA International LLC, Baosteel, General Mills, the Federal Aviation Administration, Oak Ridge National Laboratory, Lawrence Livermore Laboratories, all branches of the US armed forces (Army, Navy, Air Force, Marines, and Coast Guard), Stanford University, Harvard School of Business, Georgia Tech, University of Rochester Medical Center, Purdue University, and many others.

HeadquartersANDRITZ Inc.
13560 Morris Road, Suite 1250
Alpharetta, GA 30004 USA

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