Q: How can D-Six run real time on a Windows operating system. Windows isn’t a real time operating system.
A: D-Six does run real time on Windows even though Windows is not a real time operating system. The issue is that Windows cannot guarantee real time operation, even though it is relatively easy to configure Windows such that real time operation is
possible. D-Six provides the user with several ways to track timing and real time operation. The following discussion is presented, with some tests that pursue this topic further. The main point is that if you configure a machine to run D-Six w/ few or no other operations running
concurrently, Windows can maintain a very accurate real time performance running complex models at a high frame rate (see F-18E/F hardware in the loop application).
Read more on D-Six Timing.
Q: How can we develop our own models in D-Six?
A: D-Six is built for that! The Developer version provides the user with a wide range of Wizards to assist the model developer in building a simulation model, establishing a model shell that the user than populates with their model specific code. The templates allow the user to set up their required simulation functions from D-Six’s library, or incorporate their own. A number of example projects are also provided for reference. In addition, D-Six has a number of embedded tools and interfaces to further assist the rapid development and validation of flight models, including ways to easily import data tables, manipulate them graphically once imported, tools for overdriving vehicle control stick, surface or state data, etc. In addition, code development for your DSix project can be accomplished using the Microsoft Visual C++ (not included) development environment. The Developer package provides the ability to import MATLAB developed data and components further expanding the methods of model development. Finally, a new model tool under development, D-Six SimGen, will allow users to rapidly build and prototype models directly from a three view using Vortex Lattice (HASC2002) code – permitting users to go directly to D-Six model simulation data tables from the drawings.
Q: Can we get our existing models running in D-Six?
A: Yes, one of the key features of D-Six is the ability to easily incorporate other source code objects for use in the simulation project. D-Six allows the user to build a mapping function that essentially cross references the variables in your
external simulation code that you want or need D-Six to access. In this way the I/O from your code object can communicate with D-Six and be called from D-Six to be used in the simulation loop. This process has been used to incorporate other legacy code ranging from autopilots and
control systems to an entire trainer flight model, including data tables, lookup and integration functions (AV8-B link). In each case, the required I/O variables were mapped into D-Six, the object was compiled on the PC ( a PC compliable language required) and then called from D-Six as
a dynamic link library. Obviously, the code object must be encapsulated, i.e., any functions called from the code must also be available for successful compilation. Using non-source files (i.e. binary is possible if they have been compiled on the PC.
Q: What hardware can D-Six talk to?
A: The short answer is any thing you want it to. D-Six comes with the ability to communicate with any Microsoft Direct Input device, which today means virtually any joystick, mouse, or other commercial input devices. For communication to other PC
based hardware interfaces, Bihrle can provide a number of modules that enable the communication with A/D cards such as the National Instruments NiDaq series of PC based interface cards, serial and Ethernet interfaces, shared memory interface cards, etc. The Developer application also
provides the user with a module “Wizard” that sets up a module project for the user so they can build a custom module application for their own communication interface if desired (Fokker Link). Bihrle will also develop custom hardware interfaces for users if needed.
Q: Will D-Six run on any other operating system other than Windows?
A: As of this time, D-Six is strictly a Windows based software application. It was designed to use all the Windows based interfaces, hardware and graphics capability available with this OS, and because of this, doesn’t port easily to other OS
such as Linux. We have several users whose primary development environment is Linux, but are using D-Six for a flight model host and hardware interface (see reasons above) using one of the communication capabilities mentioned above to talk to their Linux based applications. Further,
model components from other environments and operating systems have been transferred into D-Six as discussed above, again for the flight model host application. Using our Aeroport tool, we have also exported complete models from D-Six to a code compatible object for compiling and
linking on a Motorola based Wind Rivers Real Time OS application, in this case D-Six was the development environment for a UNIX full flight sim application. So while D-Six won’t run on Linux (yet!), there are a number of ways to use D-Six in conjunction with a non-Windows OS.
Q: Can D-Six really run a full flight simulator flight model?
A: A lot of effort has been spent on making D-Six’s table look up algorithms very efficient in order to allow the real time operation of the most complex simulations. This was originally done because the computers in use at the beginning of the
software development were 486s and the earliest Pentiums. Obviously, the advance of the processing power has only made the real time operation of complex models easier, and we’ve been able to add features such as an out the window 3-D graphics display, instrumentation and strip
charts while still maintaining real time operation with these models on a single processor. As a result, the real time operation of full flight simulator models is easily achievable.
Q: Can you network D-Six together w/ other D-Six users? Can D-Six network w/ other sim environments/platforms? Does D-Six support DIS and/or HLA networking?
A: D-Six users can use the D-SixNet module to connect users across a LAN or across the Internet. This is a client server application that provides the user with a D-Six specific network and is designed for high performance networking that supports,
ACM, formation and aerial refueling applications, or any networking application where minimum latency is an issue. D-SixNet provides the user with a very flexible networking environment where the user is free to define the information distributed to the other D-Six applications on the
network. It is use in a number of multiple vehicle UAV simulation applications where communications between each UAV must be easily configured for both content and system latency models.
D-Six can network with other sim applications with the development of a communications module specific for the other target application. This is typically built by the user using the module Wizard or by Bihrle specifically for a users’ network requirements.
D-Six does not natively support the DIS or HLA network protocols. D-Six has been included in large HLA applications through the use of a custom communication interface or through the use of one of the third party network applications such as Mak VR-Link or MetVR’s VRSG. We are
still investigating as to whether or not to enable D-SixNet function as a HLA RTI.
Q: Can you do parameter extraction w/ D-Six, if so what kind?
A: The current D-Six parameter extraction tool is a built in equation error
(or analog matching) capability. This tool allows you to import flight test
(or other simulation output, say from another simulation application) and "overdrive" all or part of the simulation. When you use the tool to drive all the state variables (i.e., angle of attack, sideslip, rates, controls, airspeed, etc.)the simulation does not integrate the equations of motion, but does a
summation of all the table variables at each time step of the imported test
data. It also uses the state information and the input weight and inertias
to extract the six aerodynamic coefficients from the flight data. What
results is a simulation time history of the predicted coefficients as well
as a similar time history of the flight extracted coefficients. These time
histories are then available for a number of analyses, starting with direct
comparison plots. Because we also have the simulation's components and state variables easily available for plotting, one can quickly identify the source
of any mismatch between the simulation and flight test, and using the
database editing tools available in D-Six, quickly modify and evaluate the
effect of any changes. We have also used the exported time histories in other tools such as MATLAB to perform correlation analysis with the simulation and flight test coefficient time histories. In these cases, the software performs an analysis that provides correlation coefficients
for all the simulation states, so that the user can identify the variable that has the highest correlation with the error between flight and simulation. For example, if a mismatch was seen between the simulation and flight in side force, the analysis would provide a correlation with all
lateral state variables, such as sideslip angle roll and yaw rates, controls etc., as well as correction derivatives to improve the match. D-Six’s new scripting interface that can also interactively communicate with and control MATLAB provides the user with a number of tool
development options for more advanced flight/sim data analysis and extraction.
Q: Can I get my aircraft geometry in D-Six’s out the window view, if so how?
A: Yes you can. D-Six’s 3-D graphics window uses the Direct X graphics API for maximum performance so that the simulations can use the external and out the window views concurrently with the real time operation of the simulation model. There is
an interface that lets the user select the model geometries to be displayed in the external view, but they must be in Direct X format, typically identified with a .x suffix. Models can be downloaded from a number of websites for free as well as for a fee, email for a list of available
sites that we know of that carries these models. Many models are available in 3D Studio format, identified with a .3ds suffix, and can be converted with a number of graphical modeling tools. We use a tool call Truespace (http://www.caligari.com/), primarily since it is more cost
effective than some of the other tools out there. Obviously, you can build your own custom model with these tools, or import files from CAD programs such as AutoCad or others and texture and export the completed model in Direct X format.
Q: Can I get other terrain models in D-Six’s out the window view?
A: We built the external / out the window view window as an interface primarily to provide developers and pilots with a way to evaluate and fly their models on a low cost platform yet still give the users a 3-D terrain visualization. We purposefully
limited the number of available terrain models to the three that are available to ensure that the performance on a single machine with a single processor would be capable of providing both the out the window views and the ability to run the simulation real time. In other words the
external view window was built as a tool, not necessarily as a display generator. Nevertheless, we have built a full screen application that allows the user to set up a multi channel display application, taking advantage of Windows multi screen capability. We still don’t provide
the user to change the external view, however. We made a decision to not get caught up in the graphics development side of things, since there are a lot of people already working very hard in this area. We do have interface modules that will communicate with some of these products, such
as the fine MetaVR image generation (IG) hardware that allows users to build import, manipulate, their own worlds by using these IGs. That said, with the graphics industry constantly improving the capability of their hardware, we may yet revise the graphics to allow the user to import a
DEM database and texture with simple textures or import a simple OpenFlight world. Again this would be to provide a more limited capability than what is available in the specialized hardware, but would allow the use of more specific terrain than what is currently available with the
existing D-Six graphics.
Q: What kind of training do you get – can Bihrle support additional customized training, engineering development?
A: D-Six Developer comes with three days of training at our Hampton, Va. facility. We attempt to direct the training program to the customer’s specific application of D-Six to maximize it’s effectiveness, for example; if you primarily
intend to do model development and validation work, we request that you send or describe a typical model structure and database that you would typically use and we will demonstrate the model development and validation according to your needs and formats. If you need to host and deploy a
legacy model or model components, following the basic software operation review, we will work with you to host the model and or components as part of the training. If what you need to do falls outside the typical allotted training time, we can customize the training further, with
additional time for your particular needs at an engineering rate. Bihrle’s company background is flight model development, validation and analysis, so we are available to support whatever your project requires.
Q: What D-Six package should I get?
A: D-Six comes in three packages, Desktop, Developer and Multi Model. The Developer package is the typically recommended package since it includes all the development Wizards, toolsets and libraries needed to develop a complex engineering or training simulation. The Desktop application does not contain many of the development tools and is primarily intended to run existing simulations. It still retains most of the graphical and model database manipulation tools and interfaces, so it still is a very powerful simulation platform for analysis and visualization. It is also heavily used as a second copy of D-Six that allows users to deploy models developed in the Developer package to other applications, such as a cockpit, or hardware in the loop. The Multi Model package is a bundling of a Developer package and a Desktop package along with the D-SixNet networking module that provides a cost effective way for users to build a multi vehicle environment.
Q: How can I receive more Information on D-Six?
A: More information can be sent to you by filling out this form.
Q: I installed D-Six but cannot activate the program when the icon is selected ?
A: If, after rebooting, you still recieve the same errror message there may be a compatability isssue with the version of the key drivers shippped with D-Six. D-Six uses Rainbow sentinal Pro, and updated drivers for the language version can be found here
Key Features
Tools
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Description
