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Simulation, optimization and regression pre-selector gearshift models in the urban bus transmission are designed. Parameters of pre-selector gearshift algorithm, allowing to reduce loading of transmission elements and increase smoothness of switching-over process are synthesized. ...The article deals with parameters optimization of pre-selected gearshift algorithm in the urban bus transmission. With provision for specifics of under investigation process the research technique and toolkit of complex oscillatory system syntheses are offered in the report, including choice of strategy and method of deciding the multicriterion problem, development simulation models of pre-selector gearshift process, motivation and choice of efficiency criterions, searching area, initial approach and operated parameters.

Design activity on the University of Detroit's (U of D) entry in the 1972 Urban Vehicle Design Competition began in September 1971 with 60 senior engineering students in an interdisciplinary design course. ...The U of D urban vehicle design concept was awarded sixth place overall, and the top awards in safety and emissions for liquid fueled internal combustion engines.

The Seoul-14 Mode has been developed to simulate actual, driving conditions in Seoul. Driving patterns were studied in Seoul along 19 representative roads using a instrumented test vehicle. The speed versus time history, the transmission gear position, and the fuel consumption rate were recorded and the data were analysed to determine the traffic characteristics in Seoul. The average speed, the total length, and the total time of the Seoul-14 Mode are 30.1km/h, 11.94km, and 1,427 seconds, respectively.

City buses electrification gains increasing interest as a promising solution for both zero emissions in urban environment and energy consumption minimization. Nevertheless, global spread of battery electric buses may be currently questionable, mainly due to traveling range limitations. ...In this respect, the aim of this work is to elucidate performance aspects of battery electric powertrain systems for urban buses. Instead of exhaustive testing, cost-effective model based vehicle analysis is proposed for quantifying and understanding electric propulsion system performance and respective vehicle energy consumption. ...First, an indicative 12-m battery electric urban bus model was developed and its performance was simulated under both steady state conditions, as well as the legislated Braunschweig driving cycle.

Global warming has put the transport sector, a major contributor of CO2 emissions, under high pressure to improve efficiency. In this context, ultra-light vehicles weighting less than 500 kg, as well as hybrid powertrains, are nowadays seen as promising development trends. The design process of the powertrain of a vehicle combining the advantages of the two concepts is presented in this paper. Through a performance study based on a simple MATLAB model, and mathematical simulation, a proposal is made. A powertrain using a battery and supercapacitor 48V dual power source network, two electric motors and clutches to switch between conventional, parallel, series and full electric modes proves to be an interesting system in terms of performance and costs. A simulation study conducted on a scenario with different outcome possibilities showed that high modularity of the system allows to achieve fuel efficiencies equivalent to approximately 3 l/100 km on the Artemis cycle.

This SAE Standard is equivalent to ISO 362-1:2015 and specifies an engineering method for measuring the noise emitted by road vehicles of categories M and N under typical urban traffic conditions. It excludes vehicles of category L1, L2, L3, L4, and L5. The specifications are intended to reproduce the level of noise generated by the principal noise sources during normal driving in urban traffic. ...The specifications are intended to reproduce the level of noise generated by the principal noise sources during normal driving in urban traffic. The method is designed to meet the requirements of simplicity as far as they are consistent with reproducibility of results under the operating conditions of the vehicle.

Federal urban drive cycle and on the road. Fuel economy improvements of up to 24% were achieved on the road, and up to 25% on the chassis dynamometer over the urban cycle, confirming computer predictions. ...Fuel economy improvements of up to 24% were achieved on the road, and up to 25% on the chassis dynamometer over the urban cycle, confirming computer predictions.

The transmission parameters of an urban bus are optimized. The result shows a marked improvement in the fuel ceonomy of the urban bus.

This report seeks to identify emerging trends in urban mobility and road safety in respect to COVID-19. This is followed by a discussion of how we could shape our mobility future as communities begin to reopen.

With proper design and control, the fuel economy in urban driving can be significantly improved without much change from conventional drive train to the mild hybrid drive train.

Examples are given of fuel economy for an urban cycle, and performance of these engines with an infinitely variable transmission and with a power shift automatic transmission.

The moving baseline is given in terms of engine specific weight and volume and vehicle fuel economy and energy intensity on both the EPA urban and highway cycles. Recent advances in conventional engine and vehicle design have lead to significant improvements in all the baseline areas.

For the first time ever, a new hybrid system using a 42-V power supply system has been developed for better fuel economy, lower emissions and urban environment. This paper introduces the system configuration, features and gives actual vehicle evaluation results. ...Installing this system on a direct injection 3.0 liters engine with a 5-speed automatic transmission improves fuel economy by about 40% in the Japanese standard urban mode, when compared to the average fuel consumption of vehicles in the same class without the system.

There are basically two different systems in operation: Urban Traffic Control (UTC), Remote Monitoring (RM), and some other smaller systems. The principal system is the UTC which controls some 2000 traffic signals in London.

The authomatic control of a normal production mechanical clutch has the objective of increasing driver confort in urban traffic. Such a device will require a well suited control strategy and a very carefull experimental analysis to ensure correct and reliable operation during the start of the vehicle and gears shifting operation.

This cycle simulates an urban route of 12.07 km with frequent stops. The maximum speed is 91.2 km/h and the average speed is 31.5 km/h.

A Transient System Optimization procedure applied continuously over the federal urban driving schedule, including cold start, validated the postulated control laws.

For the Taurus, the fuel consumption variability within one standard deviation was shown to be under 0.5% for eight repeat Urban Dynamometer Driving Cycles (UDDS). These results were valid with the transmission warming system active or passive. ...For the Fusion, pre-warming the transmission reduced fuel consumption 2.5% for an urban drive cycle at -7°C ambient temperature, with 1.5% of the 2.5% gain associated with the transmission, while consumption for the US06 test was shown to be reduced by 7% with 5.5% of the 7% gain associated with the transmission. ...For +22°C ambient tests, the pre-heated transmission was shown to reduce fuel consumption approximately 1% on an urban cycle, while no benefit was seen for the US06 cycle. The simplified modeling results showed gains in efficiency ranging from 0-1.5% depending on the ambient temperature and drive cycle.

It is found from the simulation that the regenerative braking algorithm including the CVT ratio control provides improved fuel economy as much as 4 percent for federal urban driving schedule.

The concept enables the vehicle to operate as a dual mode hybrid, including an extended all electric urban range via an optional plug-in mains electricity connection. The transmission is coupled to 2 high efficiency permanent magnet brushless electric motors, which together occupy no more space than a standard 6 speed manual transmission.