An Image Generator PC-cluster for a High Flexible Multi-simulator Configuration

In the last several years, PC-based real-time image generator (IG) technology has rapidly advanced on what was once the domain of high-cost specialized computer platforms. As processor speeds increased this market once dominated by million and multimillion dollar hardware-based solutions gave way to solutions revolving around commodity graphics chips enclosed in the PC-chassis. With these changes a new (and sometimes old) set of opportunities and challenges have presented themselves to system integrators and visual software specialists. In 2003, the DaimlerChrysler (DCX) Driving Simulator Lab in Berlin began the process of upgrading most of its major subsystems. Included in the upgrade was the replacement of the IG. The IG upgrade included the requirement to simultaneously drive one of several simulators in a way that allowed for rapid reconfiguration depending on the daily operational needs of the laboratory. The implemented solution is now in place and consists of 18 PC-based IG channels which may be reconfigured to run multiple simulators or via “channel ganging” a single multi-channel driving simulator. In addition to the requirement for rapid reconfiguration, a second requirement stipulated that the system was to rely on industry standards and COTS equipment in order to lower system maintenance costs. The basic software package and the visual database format conform to this requirement. The visual software that is specific to driving simulation, however, was developed by gForce Technologies. The software provides an identical interface to all DCX simulators regardless of the number of IG channels each system has been configured to utilize. A programmable Ethernet switch is used to partition the network of graphics PCs into a number of virtual sub-LANs, thereby isolating the real-time communications of the various IG subsystems. The Berlin installation currently has 8 projectors and 13 monitors to which arbitrary IG channels may be connected. The graphical output of all PCs is routed through a programmable video switch to the target display devices.