Article: Simulation gets going

Amongst the software behind so many ingenious product designs nowadays, one name keeps cropping up: VisSim. The latest release looks set to increase its application even further, as SAMIR KHAN finds out.

VisSim, the increasingly popular Windows-based program for the modelling and simulation of complex dynamic systems, continues to make substantial moves forward. It has been used on a number of high-profile projects recently (see panel) and the developers have announced a brand new version will be available in the next few weeks.

Version 5 of VisSim is faster than ever, and even without taking into consideration the speed of setting up models provided by its unique building-block interface, VisSim is up to ten times as fast as the best-known ‘traditional’ simulation software.

Other features include group block alignment commands, automatic dialogue creation from data tables, multi-windowed plots, and multi-level undo. There's also faster, tighter code generation, new signal generation blocks (sawtooth, triangle, square wave), new matrix operations, visual comparison of two diagrams and a multiple diagram interface. If you'd like details on new VisSim 5 sent to you as soon as they're available, use the reader enquiry card. It now really is the most accessible and powerful simulation software available for the PC.

The Segway
The Segway Human Transporter (HT) launched earlier in the year in a blaze of publicity is an extraordinary vehicle which is faster than walking, but with none of the obstacles or limitations of conventional transport.

VisSim Motion Development Software was used in the development of the vehicle, which balances through a technology called dynamic stabilisation.

Dynamic stabilisation works the same way as the balance in the human body, using gyroscopes and tilt sensors, software and circuit boards and high powered electric motors instead of the balance provided by the inner ear, brain to process and send commands and muscles to carry out these actions. So a powerful simulation tool was needed, to mimic the way the human body works.

John David Heinzmann, Lead Engineer, Motor Drive Development at Segway LLC, enthused:

"When we developed the wheel motor drives for the Segway Human Transporter, VisSim was a great tool for simulating control algorithm behaviour, tuning loop gains and verifying that what we built was behaving as expected".