Speed-measurement model utilising embedded triple-loop sensors

Vehicle speed is an important parameter in the measurement of road traffic. At present, double-loop sensors are generally used for vehicular speed measurement. However, these sensors incur errors caused by scanning time, spacing between double loops, irregular vehicle trajectories and the presence of multiple vehicles in the detection zone. In this study, the authors suggest a new model for vehicular speed measurement that uses a set of triple-loop sensors and an error-filtering algorithm to improve the accuracy of speed measurements. In the field tests performed in this study, all percentage errors of vehicular speeds measured by the proposed model were within the limit of error tolerance (±5%). Moreover, the variance of percentage errors was reduced. Consequently, the proposed model significantly improves the measuring accuracy of vehicle speed.