Optimizing system design for rapid development, fast execution and re-use [test systems]

When developing a test system from scratch, the test engineer has many choices of instrumentation and software available. LAN- and USB-based rack and stack instruments are making strides versus their GPIB cousins. VXI and other cardcage-based platforms remain viable too. Test Executives and Microsoft's Visual Studio.NET development environment, along with "helper" toolkits, are making software development easier than ever. But there are design choices that should be made up front that can improve performance and make it easier to adapt to new applications as they arise. This paper explains instrumentation speed/performance tradeoffs, test development environments and architectural differences that the test engineer needs to know about in order to make the right decisions. To demonstrate the thinking process for system design, a system is designed from the ground up that can test an electronic throttle module (ETM) that responds to a brake input and a PWM signal from an accelerator and controls an electric motor which in turn operates a butterfly valve.