Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering
Transport Technology / Logistic Engineering



Koenis, R.E.M. Overslagsystemen voor de Citybox.
Literature survey, Report 2002.LT.5593, Transport Technology, Logistic Engineering.


A new unit load device, called the Citybox, can be used for the distribution of goods in urban areas. It is not clear how this unit load is to be transferred. This paper looks into the different kinds of transfer systems that would be applied to urban distribution of the Citybox.
The system is divided into three categories according to the way existing vehicles are capable of transferring existing load units. Each of the transfer systems has been evaluated to determine their feasibility to handle the Citybox as well as changes to the transfer systems to accommodate the Citybox.

It is possible to fit 9 rolling containers, 5 europallets or 4 industrial pallets into one Citybox. The box has a length of 2550 mm and a width and height of 2150mm. The bottom of the box has been made suitable for transport over roller tracks and slots are made on each side so the box can be handled with a forklift. At this moment the weight of the Citybox is fixed at 3450 kilograms, but in practise the average weight could be lower at 2550 kilogram.
In the fist category, the transfer systems are fully installed on the vehicle. Examples are the hook-arm system, the side-loader and the crane. Clear advantages are the low investment costs, the ease of control and the good transfer possibilities in the urban area. The disadvantages are the adjustments to be made to the Citybox, high variable costs, bad mechanization and automation possibilities and especially the bad fulfilment of the urban vehicle demands.
In the second category are the transfer systems that do not only need adjustments to the vehicle but also require machinery and/or conformation of the surroundings. Examples are roller tracks, tail-lifts and the swap body. Notably, roller tracks score from fair to good on all fronts, except for the transfer at the city border since extra transfer facilities have to be made there.
The transfer systems in the third category don't need adjustments to the vehicle, but depend completely on fixed or mobile systems on the transfer point. The advantages are the exceptionally fast transhipment and the high rate of automation. Opposite to this are high costs and the need of separate transhipment facilities.

It can be concluded that the transfer of roller tracks has the best results. But in the start phase it will not be possible to have these kinds of transfer systems installed in all the shops. So, to overcome this period, it is advised to use a pallet truck and tail lifts.
The weight of the Citybox needs further consideration, since the current design is not adjusted to a weight that conforms to the information of other sources. Another recommendation is the adjustment of the urban vehicle demands to the desired demands.


Reports on Logistic Engineering (in Dutch)
Modified: 2002.03.06; logistics@3mE.tudelft.nl , TU Delft / 3mE / TT / LT.