CONAT20103001 ANALYSIS OF A DRIVING CYCLE PROPOSED FOR BRASOV CITY Dinu Covaciu * , Ion Preda, Daniela Florea, Janos Timar, Vasile Câmpian Transilvania University of Braşov, Romania KEYWORDS - driving cycle, data acquisition, acceleration, speed, GPS, CAD programming ABSTRACT - A driving cycle is a standardised driving pattern, described by means of a velocity- time table. The typical driving profile comprises accelerations, decelerations and stops and it is simulated by software or on a laboratory chassis dynamometer. The European Driving Cycle is the common reference in Europe, but this cycle could not describe satisfactorily the driving characteristics in every urban area. In this paper is proposed a new driving cycle for Brasov city, based on real data collected using instrumented vehicles. The proposed cycle is a transitory one and it is compared with other known urban driving cycles, as global parameters. The pollutants emissions of a reference car, driving the proposed cycle and the European Urban Driving Cycle, were also compared. The onboard data acquisition equipments were GPS devices. The collected data covers typical roads of the city. It was developed a dedicated CAD software tool for data analysis and for identification of the driving patterns. The support of the application is AutoCAD and the programming language used is AutoLisp. INTRODUCTION A driving cycle consists in a series of data representing a speed versus time variation. Usually, the driving cycles are used as standard conditions for testing vehicles performances, like fuel consumption and emission level. Some cycles are established theoretically, others are determined experimentally, based on measurements of driving characteristics and identification of driving patterns [3]. There are two types of driving cycles: transitory and modal. A modal driving cycle includes longer periods of constant speed driving. A transitory cycle has many changes in speed and is representing more realistic the vehicle behaviour. As examples, in figure 1 are shown the New European Driving Cycle (NEDC) and the cycle FTP-75 used in USA. The first is a modal cycle and the second is a transitory one. Fig.1 – New European Driving Cycle (left) and FTP-75 cycle (right) A transitory cycle simulates much closer the vehicle behaviour than a modal cycle. A particular driving cycle can be considered as a characteristic of the road traffic in a certain area, like a city. Based on this idea, many particular driving cycles were developed for particular urban areas, based on statistics [9].