By Yanming Feng and Charles Wang,
Queensland University of Technology, Australia,
and
Charles Karl, Australia Road Research Board, Australia /
Presented at ION International Technical Meeting 2018
Connected vehicle safety and traffic applications depend on communication, position and velocity information to function. However, road users may have different vehicle communicating and positioning capabilities. Further, the performance of communicating and positioning could vary from time to time and location to location.
The vehicle safety system must be fully aware of the performance of vehicle positioning outputs and warn drivers when the positioning system cannot be used for the intended level of safety applications. Minimum operational performance standards about positioning have not been established in the road community.
When the dimension of a vehicle is considered, the protection ellipse for a single point can be extended to a vehicle protection bubble (VPB), obtained by drawing the protection ellipses around the exterior shape of the vehicle body. VPB shape can be approximately described by a rectangle or a parallelogram. Here, three different cases of VPB reflect three protection ellipses for 2D vehicle position errors.
This paper reviews and develops the required navigation performance parameters for vehicle positioning capability in terms of accuracy, integrity, timeliness and interrogability of positioning solutions.
It attempts to adjust the integrity performance parameters for vehicle safety positioning and provide the analysis for integrity risk, protection level and different alert limits. It introduces the error ellipse representation to visualize the protection bubble area of each vehicle on the road. Experimental results demonstrate how different capability levels meet different integrity alarm limits.
Available online via www.ion.org/publications/browse.cfm.
