Real-time simulation refers to a
computer model of a physical system that can execute at the same rate as actual "wall clock" time. In other words, the computer model runs at the same rate as the actual physical system. For example, if a tank takes 10 minutes to fill in the real world, the simulation would take 10 minutes as well.
Real-time simulation occurs commonly in
computer gaming, but also is important in the industrial market for operator training and off-line controller tuning. Computer languages like
LabVIEW
Laboratory Virtual Instrument Engineering Workbench (LabVIEW) is a system-design platform and development environment for a visual programming language from National Instruments.
The graphical language is named "G"; not to be confused with G- ...
,
VisSim
VisSim is a visual block diagram program for simulation of dynamical systems and model-based design of embedded systems, with its own visual language. It is developed by Visual Solutions of Westford, Massachusetts. Visual Solutions was acquired ...
and
Simulink allow quick creation of such real-time simulations and have connections to industrial displays and
programmable logic controllers via
OLE for
process control or digital and analog
I/O card
In computing, an expansion card (also called an expansion board, adapter card, peripheral card or accessory card) is a printed circuit board that can be inserted into an electrical connector, or expansion slot (also referred to as a bus slo ...
s. Several real-time simulator are available on the market like xPC Target and
RT-LAB for mechatronic systems and using
Simulink,
eFPGASIM and
eDRIVESIM for power electronic simulation and
eMEGASIM,
HYPERSIM and RTDS for power grid real-time (RTS) simulation.
What is real-time simulation
In a real-time simulation the simulation is performed in a
discrete time with constant step also known as fixed step simulation as time moves forward in equal duration of time, other techniques having variable step are used for high frequency transients but are unsuitable for real time simulation. In a real time simulation the time required to solve the internal
state equations and functions representing the system must be less than the fixed step. If calculation time exceeds the time of the fixed step, an over run is said to have occurred and the simulation now
lags
Laax ( rm, Lags) is a municipality in the Surselva Region in the Swiss canton of Graubünden.
History
Laax is first mentioned c. 1290–98 as ''Lags''.
Geography
Laax has an area, , of . Of this area, 35.8% is used for agricultural pur ...
behind the actual time. In simple words, real-time simulation must produce the internal variables and output within the same length of time as its physical counterpart would.
Configuring models to run in real time enables one to use
hardware-in-the-loop simulation to test controllers. It's possible to make design changes earlier in the development process, reducing costs and shortening the
design cycle.
Real-time simulation in academic curricula
Real-time simulators are used extensively in many engineering fields. As a consequence, the inclusion of simulation applications in academic curricula can provide great value to the student. Statistical
power grid protection tests, aircraft design and simulation, motor drive controller design methods and
space robot integration are a few examples of real-time simulator technology applications.
OPAL-RT Technologies Technical Paper , Real-Time Simulation Technologies in Education: a Link to Modern Engineering Methods and Practices
/ref>
See also
* Human-in-the-loop
* Simulated Real Time, a literary method unrelated to the type of computer models described on this page.
References
{{reflist
External links
The What, Where and Why of Real-Time Simulation
HYPERSIM , The Power System Simulator of Tomorrow
From Offline Simulation to Real-Time Testing