From: Conrad_Geiger@NeXT.COM (International NeXT User Groups)
Subject: Simulation Kit Brings Continuous Simulation to the NeXT
Followup-To: poster
Organization: Motorola Computer Group, Schaumburg, IL
Date: Tue, 1 Sep 1992 00:34:03 GMT

Simulation Kit Brings Continuous Simulation to the NeXT

SAN FRANCISCO, July 21, 1992-Doberman Systems today announced the
Simulation Kit, the first collection of objects specifically developed
for continuous system modeling and simulation on the NeXT computer.
Coupled with the NeXTSTEP application development environment, the
Simulation Kit provides the ideal context for developing and analyzing
object-oriented simulations.  Unlike traditional methods, where the
model to be simulated is programmed procedurally from derived
equations, the object-oriented approach is implemented directly from a
block diagram representation of the system.

Both academic and commercial users will find the Simulation Kit to be
a powerful yet easy-to-use tool for modeling, analyzing, and teaching
linear and nonlinear continuous systems, numerical integration, and
the numerical solution of differential equations.  Typical application
areas are numerical analysis, engineering systems (e.g. mechanical,
electrical, thermodynamic, and chemical), and control systems.

The Simulation Kit includes Objective-C objects such as processes,
composite processes, simulations, signals, and clocks.  Simulations
are modeled by connecting processes together with signals.  More
complex subsystems can be grouped together into composite processes,
which may then be manipulated and used as a single process.  Commonly
used processes such as summers, gains, limiters, and Euler
integrations are included with source code; users can develop their
own processes by subclassing and using the provided sources and
documentation as a guide.

A typical use of the Simulation Kit can be illustrated by simulating
the motion of an automobile.  The car's acceleration is determined by
the pressure applied to the accelerator by the driver, the slope of
the road (which depends on the location of the car), and the car's
drag (which increases with the vehicle's speed).  It is known that the
car's location and speed may be obtained by successively integrating
its acceleration.  From this information, a block diagram composed of
integrator, gain, and summer blocks can be easily assembled.  These
process blocks and the signals that connect them are implemented by
Simulation Kit objects which are organized in the same fashion as the
block diagram.  Information such as the car's position, velocity, and
acceleration may then be output as the car "moves" through its virtual
environment.  This approach to modeling provides greater insight and
intuition into the behavior of the system and allows simple and rapid
modification of the simulation.

The Simulation Kit employs several advanced features that are
unavailable in other simulation packages.  Multiple clocks allow
simulations to contain "fast" and "slow" subsystems.  Process
prioritization permits fine control over the execution of the
simulation for techniques such as cascaded integrations.

The Simulation Kit will be available in September 1992 for an
estimated price of US$XXX.YY (US$XX.YY academic).  Objects, full
documentation, and example source code will be distributed on
NeXT-compatible floppy disks.  Technical support will be available by
telephone or electronic mail from Doberman Systems

Doberman Systems was launched in 1992 to develop hardware and software
solutions for the NeXT series of professional workstations.  The firm
is committed to providing the highest quality products and services
for NeXT users and developers worldwide.

Doberman Systems, the Doberman logo, and Simulation Kit are trademarks
of Doberman Systems.  NeXT and NeXTSTEP are trademarks of NeXT
Computer, Inc.  All other trademarks mentioned belong to their
respective owners.

Doberman Systems
2027 East Ashley Ridge Road
Sandy, Utah   84092-7260

Contact:
  Mike Panzitta
  801 944-4329
  doberman!mike@uunet.uu.net
Newsgroups: comp.newprod