Understanding Real-World Variability of Hybrid Electric Vehicle Fuel Economy

The variability of fuel economy (FE) is of significant importance as that of average FE to realize FE benefits of hybrid electric vehicles (HEVs) consistently by all users in the real world. Over the years, majority of the research has been focused on improving average FE overlooking the variability. Although in recent years few studies have been focused on the reduction of FE variability, no study has been concentrated to understand why certain design has lower FE variability as that of others. This article provides a detailed analysis to decipher the reasons for the FE variability in the real world. This study considered the optimum designs based on two established design optimization methodologies considering Toyota Prius non-plug-in hybrid as a base vehicle. This study analyses the impacts of the parameters of driving patterns and the operation of powertrains on FE variability. The study explains that comparatively bigger internal combustion engine (ICE) in combination with the optimum sizes of generator motor and battery could lead to lower FE variability in the real world due to lesser time of operation of ICE to charge the battery.

Contribution to the logistic evaluation system in the transportation process in Santo Domingo, Ecuador

Purpose: The objective of the present research is to design and apply a methodology to evaluate the logistics system in the transportation process in a base vehicle fleet, which contributes to decrease the costs of distribution and to increase the performance of the logistics system of the organization.Design/methodology: The proposal of a holistic technology for the management of this process is carried out, which integrates indicators and tools that improve control and decision-making activities in this area.Findings: The application of the procedure developed in the selected organization contributed to the identification of deficiencies related to the availability of the equipment and the needs of the clients, the low technical availability of the automotive plant, the low utilization of the capacity of the freight vehicles, the absence of a plan of measures to diminish the empty routes of the transport and the overconsumption of fuel due to the accomplishment of extra trips. Aspects that contributed to the redesign of some of the main functions of physical distribution such as itinerary planning, selection of means of transport and analysis of operating indicators, aspects that favored the optimization of the number of trips and, consequently, the adequate use of the equipment and the loads to be transported, observing a saving of 15% in the fuel consumption per load transported.Originality: The originality of the present research lies in the combination of different theories and techniques that contribute from a holistic approach to the logistics evaluation of the transportation process, facilitating the optimization of transportation requirements, its operation and maintenance.

Kinematic scheme of manipulator for the removal of unwanted trees and shrubs in plan of the row of railways

This article discusses the layout of manipulators designed to move the working body according to a given process technology, taking into account the appropriateness of their use, which is caused by the type of the base vehicle, the type of unwanted vegetation and especially its growth, in terms of terrain and profile strip of tap railways. The question of the layout of the manipulator to allow movement of the base vehicle both on public roads and railway network, taking into account the established restrictions on the dimensions of movement.

Use of numerical optimization to determine the effect of the roll stiffness distribution on race car performance

The use of active systems for controlling suspensions has been used before in Formula One and other open wheel racing series but at present this form of active control is not allowed by Formula One regulations. The roll stiffness distribution is a key element of suspension design and it has an influence on the dynamic weight transfer of the vehicle. In this paper, the roll stiffness distribution has been optimized during a calculation process to simulate and quantify the possible benefits of controlling the distribution of roll stiffness between the front and rear axles of an open wheel race car. The roll axis concept has been used to provide the roll component to the lateral load transfer evaluation. The benefits shown by the optimization of the roll stiffness distribution have created a mean handling performance improvement over the base vehicle of over 10 per cent, which on the lap of the Barcelona Grand Prix circuit yielded a lap time improvement of 2.71 s, using a quasi-steady-state calculation method. Additionally, it has been shown how this improvement has been realized in terms of the change in vehicle dynamics. This research also shows that circuit dependent analysis is possible to exploit the value of the static setting of the roll stiffness distribution. Further work and validation are required to explore this avenue of vehicle set-up optimization, but it does appear that the optimized calculation approach offers a way of helping to make an objective choice of a static roll stiffness distribution setting for particular circuits.

Safety Aspects Related to the Development of a Full Aluminum Frame for the Year 2000, 1500 Series Chevy Suburban

In conjunction with the FutureTruck collegiate design competition, The University of Wisconsin - Madison has integrated an all aluminum frame into their four-wheel drive, charge sustaining, parallel hybrid-electric sport utility vehicle. The base vehicle is a 2000 Chevrolet Suburban nicknamed the “Moollennium” and weighs approximately 2400 kg. The original GMT 830 frame constitutes 10% of the Suburban’s weight and has the largest weight reduction potential. In a cooperative effort with Tower Automotive, the University of Wisconsin-Madison has modeled, stamped and constructed two full aluminum frames using the GMT 430 tooling. The first frame, the UW 430 AL, was assembled to replicate the GMT 430 frame, while the second-generation frame, the UW 830 AL, mimicked the GMT 830 frame. FEA and traditional deflection and bending calculations were used to stiffen and strengthen the aluminum frame to acceptable levels. Front horn crush tests were used to optimize frontal impact energy absorption — the UW 830 AL design absorbs 36% more energy than the original GMT 430 steel frame with a 40% reduction in peak load. The complete aluminum frame weighs 120 kg — 98 kg lighter than the steel GMT 830 frame and 130 kg lighter than the steel GMT 430 frame.