SimCreator supports high performance solutions.  Typically, the driving simulator software iterates at 60 Hz update rate to support more data resolution for visuals subsystem update rate, high-resolution terrain query, and rapid system response.  Driving simulators in a host/visual channel configuration built with RTI's SimCreator technology have shown less than 50 ms measured latency from step input on the host to visuals response. 

Dynamics
Fast, accurate vehicle dynamics are the cornerstone of any high performance driving simulation platform.  RTI's SimVehicleLT product controls our simulation vehicle dynamics.  SimVehicleLT can be configured to represent a variety of wheeled vehicles through selectable input data files.

SimVehicleLT is made up of models of the four corners of the vehicle that are coupled with a 6DOF Body component.  A powertrain model calculates the torques at the wheels based on brake pedal, gear, and accelerator pedal inputs.  Each vehicle corner component takes into account spring and damping rates, bump stops, anti-sway bars, anti-squat anti-dive geometry and roll axis height.  The unsprung mass is modeled as a separate body connected by a prismatic joint to the base body.  In addition, we use a Magic Formula tire model to predict the tire forces at each wheel.

The powertrain model contains complete engine, transfer case, differential, and torque converter models.  The engine model is based on a torque lookup map. You can specify parameters such as torque converter efficiency, shift maps, and gear ratios in the SimCreator data file. You can also incorporate lockup transfer cases and differentials. The brake model includes models of the master cylinder, prop valves, wheel cylinders, pad friction, and rotor and wheel diameters.

Cabs, Control Loading, Visual Displays
Systems developed with the RTI driving simulation platform can make use of a variety of cab, control loading, and visual displays configurations.  The simulation model can be configured to support the data input/output requirements of various cab types.  Keyboard controls, PC game-style steering wheel and pedal sets, custom mockup vehicle cabs, or fully instrumented real vehicle cabs are fully supported.    

An optional, high-fidelity control loading system provides feedback on the steering wheel that is directly coupled with the vehicle dynamics at 2000 Hz.  Important factors such as power steering boost curves, and tire aligning torque are included in the steering model.  You have the power to configure the steering feedback to represent the vehicle you're simulating.

Visuals
The quality of visual graphics will often make or break a customer's acceptance of a simulator and directly affects the driver's ability to be immersed in the virtual environment.  RTI's visual subsystem can present graphics generated in OpenFLT, VRML, and most OBJ and 3DS formats.  Smooth visual presentation is attained through a 60 Hz visuals update rate and close coupling with the SimCreator core software model.

Visual effects such as fog, rain, dynamic shadows, headlights, deformable terrain, ambient lighting models, and pre-rendered light maps are supported.  Visual rendering techniques such as full multi-texture, detail texture, bump mapping, environment mapping, parallax mapping, light sources, and vertex or fragment-based lighting models are supported.  In addition, RTI's visual subsystem is tightly coupled with the terrain query subsystem to provide highly accurate correlation between the terrain and visual representations.

Scene and Scenario Control
RTI's scenario control subsystem provides the ability to control nearly all aspects of virtual traffic, pedestrians and simulator operation.  Scenario development starts with the SimVista scene authoring tool.  SimVista makes it possible to drag and drop objects into the virtual world and to give them scripted behaviors to bring them to life. 

SimVista comes  with pallets of objects that can be placed in the scene.  A set of tiles have been developed that can be arranged together within SimVista to make a seamless driving environment.  Objects such as buildings, trees, parked vehicles, terrain features, signs, construction barriers, etc. and can be added to enhance the visual complexity of the scene.  Still more objects can be added and assigned behaviors that will play out during scenario execution such as sensors, vehicles, and pedestrians. 

The sensor suite includes proximity, planar time-to-collision and rectangular sensors, in addition to start and end points. These objects are assigned JavaScript-based scripts that execute at runtime when entities in the scenario interact with the sensor.  Within the scripts, commands can control the vehicle,  pedestrian and traffic signals,  sounds, text and image display, and changes in environmental conditions, etc.  A full set of data collection and measurement objects are also available within the scenario control system.  All the tools you need to author your own simulation scenario content are available with the scenario scripting system.

Motion Cueing
Motion cues are one of the best ways to enhance the driving experience in your driving simulator.  RTI’s driving simulation software controls motion through OverTilt, RTI’s motion control software algorithm.  Based on the type of application, specific driving tasks, and program budget you are working with, RTI’s expert staff can recommend specific motion system configurations.  The motion control algorithm supports 3 DOF and 6 DOF motion systems and can be tuned during runtime with a simple graphical user interface.