lation, the modeling tools were interfaced to the rapid prototyping and HIL systems through automatically generated prototyping code. Because system modeling tools could easily be used with rapid prototyping systems, these tools became an integral part of the automotive control design process. Rapid prototyping systems ranged from rugged, in-car units to large rack-mount systems supporting numerous input/output (I/O) channels. The standard processor for the prototyping systems was the DSP or Di
gital Alpha processor.
Figure 1 shows a typical control system modeled as a block diagram. The controller interfaces to the plant or engine through actuators and reads values or signals from sensors on the plant to form a closed-loop control system typical of that found in automotive and aerospace design. Using Model-Based Design, the graphical model can be simulated and tested to prove both the control design and the integrity of the plant model.
Figure 1. Typical control system modeled as a block diagram
Figure 2 shows a diagram of the use of automatically generated software code from the control side of the model to run a rapid prototyping system, which tests the control algorithms in real time on commercial rapid prototyping equipment. In the same way, automatically generated software code from the plant side of the model can be used to simulate the responses and operation of the plant to test prototype controllers in real time on commercial HIL equipment.
Figure 2. Automatic code generation is used for rapid prototyping, hardware-in-the-loop simulation, and embedded system deployment.
Aerospace industry finds value in HIL systems
While the automotive industry accepted rapid prototyping systems, the aerospace industry found significant value in the use of HIL systems. Aerospace companies found that they could simulate the flight and environmental characteristics of their planes, missiles, and satellites. They developed sophisticated FORTRAN mod