36 research outputs found
Analisi sperimentale della capacità degli accessi di un veicolo per il trasporto collettivo
No full textThe packages clustering optimisation in the logistics of the last mile freight distribution
No full textThe paper refers to the modelling and simulation of an innovative urban freight distribution scheme. Packages destined for receivers in an urban area are firstly delivered to the urban distribution centre (UDC); each package is characterised by an address and dimensions. The load units are consolidated in the UDC with packages. Each load unit is addressed to a temporary unloading bay, where receivers are after in charge of collecting their packages. The paper concerns a methodology for the load units consolidation which minimises the overall distance travelled by receivers, taking into account the load unit capacity and the maximum walking distance the receivers accept to collect their packages. A fuzzy k-means clustering algorithm has been adopted. The fuzzy clustering algorithm is recalled by a simulation model of the proposed transport system. The methodology has been applied to the case study of the historic city centre of Genoa, Italy
A new urban freight distribution scheme and an optimization methodology for reducing its overall cost
No full textPurpose: The paper refers to an innovative urban freight distribution scheme, aimed at reducing the externalities connected with the freight delivery process. Both packages destined to commercial activities and to end consumers (e-commerce) are taken into account. Each package is characterized by an address and dimensions. In the proposed transport system, freight is firstly delivered to the UDC on the border of urban areas through trucks or trains which perform the long distance transport. After, freight is reorganized and consolidated into load units, i.e. the FURBOT boxes, according to packages dimensions and to the addresses of receivers. Each box is addressed to a temporary unloading bay and it is delivered there by a FURBOT vehicle. The receivers are in charge of collecting their packages in the related unloading bays where they have been delivered.
Methods and results: The paper concerns a methodology for optimizing this freight transport system’s performances. The overall methodology receives in input the actual freight demand and the road network, and finds the transport system parameters (number of required FURBOT boxes, their temporary unloading bay, the FURBOT fleet dimension and the FURBOT vehicle routing) that minimize the system overall cost. The overall cost is a sum of the users’ cost, which depends on the distance they have to walk for collecting their packages in the FURBOT box, and of the operator’s cost, which depends on the number of required boxes, the total distance travelled by the FURBOT vehicles and the required number of FURBOT vehicles.
Application: The overall procedure has been applied to the case study of Barreiro old town, a suburb of Lisbon, Portugal. © 2015, The Author(s)
Analisi sperimentale della capacità degli accessi di un veicolo per il trasporto collettivo
No full textOptimization of the FURBOT urban freight transport scheme
No full textThe paper refers to an innovative urban freight distribution scheme, aimed at reducing the externalities connected with the freight delivery process. Both packages destined to commercial activities and to end consumers (e-commerce) are taken into account. Each package is characterized by an address and dimensions. In the proposed transport system, freight is firstly delivered to the urban distribution centre on the border of urban areas through trucks or trains which perform the long distance transport. After, freight is reorganized and consolidated into special load units (FURBOT boxes), according to packages dimensions and to the addresses of receivers. Each box is addressed to a temporary unloading bay and it is delivered there by a smalllelectrically powered vehicle (FURBOT vehicle). The paper concerns a methodology for optimizing this freight transport system's performances. The input data are the actual freight demand, the road network and the public policies. The methodology determines the best number of FURBOT boxes which minimizes the system cost. The overall cost is a sum of the users cost, which depends on the distance they have to walk for collecting their packages in the FURBOT box, and of the operator cost, which depends on the number of boxes, and the total distance travelled by the FURBOT vehicles. The minimization problem has been approached by a Simulated Annealing procedure. The methodology recalls two sub-problems: a first sub-problem to determine the optimum clustering of packages in the FURBOT boxes, and a second sub problem to determine the best routing of FURBOT vehicles. The methodology has been applied to the case study of Genoa city centre, Italy
A.S.I.A. (Advanced Simulation Interoperable Architecture): a support in the traffic management
No full text
A new shared vehicle system for urban areas
No full textThe paper concerns the conceptual design of a transport system for pedestrian areas. The proposed transport system is based on a fleet of eco-sustainable Personal Intelligent City Accessible Vehicles (PICAVs). The vehicles are shared through the day by different users and the following specific services will be provided: instant access, open ended reservation and one way trips. Referring to the proposed transport system, a new methodology to optimise the fleet dimension and its distribution among the stations is proposed in this paper. The problem faced is an optimisation problem where the cost function to be minimised takes into account both the transport system cost and the user costs that depend on the waiting times. A random search algorithm has been adopted. Given a fleet dimension and its distribution among the stations, the waiting times of the users are assessed by a microscopic simulation. The simulation model tracks the second-by-second activity of each PICAV user, as well as the second-by-second activity of each vehicle. The overall methodology has been implemented in an object-oriented simulator. The proposed transport system has been planned and simulated for the historical city centre of Genoa, Ital
A methodology for planning a new urban car sharing system with fully automated personal vehicles
No full textPurpose: The paper concerns a transport system for pedestrian areas, based on a fleet of fully-automated Personal Intelligent Accessible Vehicles. The following services are provided: instant access, open ended reservation and one way trips. All these features provide users with high flexibility, but create a problem of uneven distribution of vehicles among the stations. A fully vehicle based relocation strategy is proposed: when a relocation is required vehicles automatically move among stations. The paper focuses on a methodology that allows to plan the proposed transport system for wide pedestrian areas. The methodology aims to determine the fleet dimension and the relocation strategy parameters which minimize the system cost. The system cost takes into account the level of service and the efficiency. Relocation strategy parameters define when and among which stations relocations should be performed. Methods: The problem faced is an optimisation problem where the search space is defined by all the possible fleet dimensions and relocation strategy parameters. As this cost function could be a multipeak function and since the search space is discrete and extremely large, a random search algorithm has been adopted. Because of the characteristics of the problem, a parallel optimization technique was required. Given a fleet dimension and relocation strategy parameters, a microsimulator models the activity of each user, as well as the activity of each vehicle over time with the aim of finding the level of service and the system efficiency. Results, conclusions and application: The methodology has been applied to planning the proposed transport system for the centre of Barreiro, Portugal
Personal full electric vehicle PICAV: Non linear dynamic model and simulation (Article)
No full textRequest of sustainable personalized transport is growing in different areas of service robotics, for aid to mobility of elderly and motion disabled people, for freight delivery in urban environment, for passengers transport in restricted zones as airports and greens because of the small dimensions, tiny footprint, on-board intelligence, friendly human car interface and zero environmental impact. The paper studies the feasibility of an electric vehicle with four non steering wheels considering as driving principle the skid steering that has been mainly used for tracked vehicles.The vehicle is a complex nonlinear multi body system with numerous mobilities either in stiff and in elastic motion. For evaluating the vehicle performances, the maneuverability and stability behavior it is needed the availability of a model able to describe all the significant motion modes in different operative conditions. The paper presents the PICAV model and some results of the simulation campaign that demonstrated its soundness and reliability. © 2015, North Atlantic University Union NAUN. All rights reserved
