Introduction

Real time simulation can be defined as the ability for the Adams model to complete at a rate equal to, or faster than, the actual "wall clock" time at which the physical system would run. Real time simulation enables hardware-in-the-loop (HiL) and some software-in-the-loop (SiL) workflows. Adams Real Time is a set of capability to help Adams models run at real time both "online" (that is, on real time operating systems) and "offline." Offline real time simulations might be done to satisfy SiL scenarios in which it is desired that the Adams model run at real time so as provide the other software tools(s) in the loop with realistic response (for example, a mechanical system responding in real time to an electronic controller). Online real time simulations might include either HiL or SiL usage or both.

Three primary factors determine an Adams model's suitability for real time simulation: model complexity, model excitation and hardware. As model complexity (for example, degrees-of-freedom, contact, flexible bodies and so on) decreases the chance of achieving real time speed increases. As model excitation frequency decreases and actuation functions get smoother the chance of achieving real time speed increases. And, naturally, as the hardware environment upon which the model is more powerful (especially CPU speed and sometimes the amount of available memory to some extent) the chance of achieving real time speed increases.

While there are many different ways to make most Adams models run faster, a set of tools exists for Adams Car models specifically with the aim of helping them achieve real time performance. See Model Fidelity Reduction and Tire and Driving Machine features for faster simulations for more details.

Beyond the fast solving Adams model itself, two key capabilities are frequently required to achieve real time workflows and are described in the sections that follow: