Effect of Sensor Errors on Network Traffic Flow Inference Based on Sensitivity Analysis

Abstract:

The effects of sensor errors on link flow inference in sensor location flowobservability problem are discussed in this paper. By using the equations of traffic flow conservation system and the model of network sensor location problem based on turning ratios at intersections, a general sensitivity analysis method is proposed to analyze the impact of sensor errors on the link flow reckoning. Firstly, the key factor is defined to represent the errors of link inferring caused by the sensor errors. Then, the total effect of multiple sensor errors on the link flow inferring is proved theoretically to be the linear superposition of the effects of single sensor error. Finally, a square road network is used to test the proposed method. Two sensor location schemes of installing sensors on the only entrance links or exit links of the road network respectively are adopted, which can both support the unique link flow inferring results. The effect of sensor errors on link flow inferring is given by using the key factor method.