چكيده به لاتين
Abstract:
Nowadays one of the most important issues for Automakers is to present a solution for reduction of fuel consumption and emissions. One of these approaches is determination of an appropriate algorithm for on-time gearshift according to conditions of vehicles equipped with automatic transmission. This thesis presents an algorithm for gearshift in order to reduce fuel consumption for combustion engines that equipped with AMT gearbox. This pattern is done based on considering a factor that is called “driver’s sportivity index”. Sportivity Index (SI) is a factor for classifying different driver behaviors from calm to aggressive driving. factors that affect the sportivity index are: vehicle speed, vehicle acceleration and throttle (pedal) position. A fuzzy logic model, was used to estimate the aggressiveness of a driver and its inputs, is based on. For a better estimation of SI, the variation of the three inputs were defined and then three coefficients K1, K2 and K3 were introduced; by combining these three coefficients, SI is estimated. A fuzzy logic strategy, is also used for the gearshift. This shifting is designed based on engine state, SI and driver’s braking state. In order to simulate vehicle performance and shifting strategy, ADVISOR software is linked to MATLAB SIMULINK. Subsequently, the results are investigated in several standard driving cycles. According to the results, fuel consumption reduction was observed compared to other similar works. Finally, genetic algorithm was utilized for optimizing gearshift strategy in order to minimize fuel consumption and emissions by applying two different methods: a) Optimizing fuzzy membership functions; and b) Optimizing gearshift strategy rules.
Keywords:
Speed, acceleration, sportivity index, fuel consumption, driving cycle, engine state, optimization
