On Strategies Improving Accuracy of Speed Prediction from Floating Car Data (FCD)

For smart mobility, speed data extracted from Floating Car Data (FCD) plays an important role in speed predictionaccuracy. However, there are reliability issues for commercial FCD due to processing of individual vehicletracking data, and imposed temporal averaging to compress data size. Furthermore, spatial discretizationsignificantly affects the accuracy of the prediction due to uneven segment lengths and highly variable dataavailability in the network. In this study, these issues are examined in detail, and several strategies to improveaverage speed prediction are proposed. An extensive FCD data from a 75-km long corridor is utilized in thecalculations. Firstly, for data reliability, several filters are applied to clean data, then, a robust algorithm is appliedto smoothen the speed data. Secondly, to investigate and reduce prediction errors due to spatial segmentation, anumber of segmentation approaches are developed, and their effects on the average speed prediction are assessed.Finally, several autoregressive prediction models are implemented and a comprehensive comparison of results ispresented.


A method to estimate traffic penetration rates of commercial floating car data using speed information
Altintasi, Oruc; Tüydeş Yaman, Hediye; Tuncay, Kağan (2022-08-05)
Floating Car Data (FCD) are being increasingly used as an alternative traffic data source due to its lower cost and high coverage area. FCD can be obtained by tracking vehicle trajectories individually or by processing multiple tracks anonymously to produce average speed information commercially. For commercial FCD, the spatio-temporal distribution of these vehicles in actual traffic, traffic Penetration Rate (PR) is the most important factor affecting the accuracy of speed estimations, despite the high num...
A comparative study on tightly coupled visual aided inertial navigation systems for unmanned aerial vehicles
İnce, Talha; Saranlı, Afşar; Department of Electrical and Electronics Engineering (2018)
An Inertial Navigation System (INS) is a combination of hardware (accelerometers and gyroscopes) and algorithms to calculate the position, orientation and velocity of a mobile platform. Because of the need to integrate the measurements over time, INS is subjected to cumulative error characteristics, hence cannot provide an accurate navigation solution over long durations. Global Positioning System (GPS) is often used for long time-long distance problems aiding INS. GPS relies on external signals received fr...
An Analytical Approach for the Calculation of Flux-Linkage Including End-Effect for SR Motors
Özlü Ertan, Hatice Gülçin (2008-06-13)
The accuracy of flux linkage-current-position curves has vital importance for designing SR motors. Analytical prediction of these curves is very difficult and as shown in this paper 2D approach leads to erroneous prediction of the flux linkage curves and hence significant errors in performance prediction of SR motors. This paper makes an important contribution to the design process by developing an approach for the analytical calculation of flux linkage-current-position curves including the end effect. As s...
Design optimization of variable frequency driven three-phase induction motors
Ertan, B; Leblebicioğlu, Mehmet Kemal; Simsir, B; Hamarat, S; Cekic, A; Pirgaip, M (1998-01-01)
An approach to optimize the design of three-phase induction motors for a wide speed range drive is considered. Two operating points in the speed range are taken into consideration. The problem is handled as a constrained optimization problem. An accurate model for the motor in terms of its dimensions has been developed which predicts the motor performance based on about 60 parameters of motor geometry.
Dynamic simulation and performance optimization of a car with continuously variable transmission
Güvey, Serkan; Ünlüsoy, Yavuz Samim; Department of Mechanical Engineering (2003)
The continuously variable transmission (CVT), which has been in use in some of the vehicles in the market today, presents the possibility of decoupling the engine speed and the vehicle speed. By this way, it is now possible to operate the engine at its maximum efficient or performance point and fix it at that operating point without losing from the vehicle speed. Instead of using gears, which are the main transmission elements of conventional transmission, CVT uses two pulleys and a belt. By changing the pu...
Citation Formats
H. Tüydeş Yaman, K. Kocamaz, and K. Tuncay, “On Strategies Improving Accuracy of Speed Prediction from Floating Car Data (FCD),” İstanbul, Türkiye, 2021, vol. 1, Accessed: 00, 2021. [Online]. Available: https://ace2020.org/en/.