Development of a Vehicle Simulator Based Testing Method for Telematics Software Development 2007-01-0945
For developing telematics devices and software, traditional development methods including unit function test, compatibility test and T-car test often show limitations. Telematics devices have various functions that require consideration of interactions among three major elements of automotive electronics - the vehicle, the device unit and the driver. KAAS(Katech Advanced Automotive Simulator) system is a virtual reality(VR) based test environment designed to test and analyze the three elements in one place. This system is an integrated system of a large scale driving simulator with HILS systems and driver analyzing systems. One of the difficult functions when constructing such VR based telematics test environment is the location based service using GPS. Because GPS receiver module and processing/display module are usually integrated into the GPS navigation unit or the telematics unit, it is necessary to provide the GPS signal in RF while one of the traditional in-door test method is to use the NMEA signal through RS-232 connection. Another popular traditional test method is the out-door recording and in-door replay of the RF signal(recorded driving scenarios). Although this method can be used for the navigation units with integrated GPS module, this pre-programmed scenario method cannot be used in the VR environment because the location of the vehicle is purely decided by the driver's personal intention during virtual driving. This paper presents the two major functions that are core elements of GPS RF signal generation which reflects the continuously changing vehicle location during virtual driving in real-time. The first function is the CAN(Controller Area Network) protocol providing the real-time vehicle status, and the second is the coordinate transformation and GPS signal generation. Using these functions, telematics devices can be simulated in the virtual environment as if the devices are installed in a vehicle driving in real-world. The GPS simulator receives the vehicle status data such as vehicle position in the 3D virtual space in real time, computes the location of the GPS satellites above the vehicle, and sends the GPS RF signal of each satellite through the RF antenna. This paper includes the vehicle status data of a virtual driving used for developing the TOPAZ middleware software in IBM Korea.