We propose a Small Smart Automated Container (SSAC), a freight container designed primarily for carrying goods to destinations within urban areas. It is designed to fit efficiently on all existing transport modes and to be moved automatically from one mode to another.
The proposed container will fit two side-by-side on existing road and rail vehicles, making it considerably smaller than existing standard containers, which fit only one in the same width.
The design will contain features that allow the SSAC to be moved and clamped to different vehicles efficiently and automatically. (Automated movement is essential because the relative small size means very large numbers of units.)
We foresee that the SSAC will also be useable with most of the proposed advanced transport systems, making these more attractive economically by enabling them to carry freight as well as passengers. We also see a potential for a new range of transport modes based on a single string of SSACs in a train.
We present a discussion of the factors which guide the design and offer an impression of how it might work in detail.
There are big problems with transporting freight within and between urban areas associated with the use of large lorries for the movement of small items. Very little automation is available for loading smaller items of freight, which means that the same vehicle tends to be used for the whole journey to avoid the cost of manual handling. The result is that large lorries are used to deliver small loads in restricted space in city centres.
Large lorries and even medium sized vans present a considerable detraction to the city environment. They tend to be noisy, smelly and obstructive. Frequently the final delivery (or collection) in narrower streets causes inconvenience to other road users. The overall energy efficiency tends to be poor.
There is well established technology for moving pallets around, which are small enough to be carried by small vehicles but, being open, are not easily compatible with being moved without supervision and in all weathers.
There are proposals for a smaller shipping-style containers, but these tend to be optimised for longer distance transport and assume a larger vehicle.
For a considerable time to come road transport will be the most important mode of freight transport and the dimensions of the SSAC, with two fitting side-by-side across the width, will provide good volumetric fill efficiency. The maximum width of lorries for nearly all Europe countries is 2.55 m with a few at 2.50 m. We propose a width of 1270 mm which would allow for a clearance of 10 to 15 mm. The outer surfaces of the SSAC would form part of the aerodynamic surface.
We propose a length of 2.4 m which would allow them stacked across the width of a lorry with its own sides which form the aerodynamic surface.
The maximum length of lorries and trailers in all European countries is 12 m which would allow up to 4 to be stacked longways with space for streamlining at the ends.
There are proposals for using tram systems to carry freight using a special vehicle or possibly by adding a trailer to passenger trams. The SSAC, with its provision for efficient automated loading, would be ideal for this application. The length would allow them to be carried across the width of many tram systems (although we note that some of the modern tram vehicles are a bit narrower).
This width and length would allow an internal floor area that would accommodate two 1.2 x 1.0 europallets
We propose a height of 1.6 m which would allow two layers of SSACs to be carried on lorries. The maximum permissible height for nearly all European countries is 4 m, so this would leave room for ground clearance and support structures.
A single SSAC would fit onto a small pick-up truck. There are very few places in a typical town that cannot be accessed by such a car-sized vehicle.
The Loading gauge of mainline railways tend to be more than 3 m wide and 4 m high (3.15 x 4.32 m for most of Europe). This would allow two layers of two SSACs side-by-side to be loaded in the cross-section inside walls thick enough to be structural and present an aerodynamically smooth outer surface.
American railway loading gauges are not significantly wider (3.25 m) but can be high enough (6.1 m) to allow three layers of SSACs.
UK loading gauges are mostly smaller than for the rest of Europe. The minimum width is 2500, enough for two SSACs side-by-side. For most of the network the maximum height above rail seems to be 3.448 m (W6a), which might be too small for two layers of SSACs, but there are some mainline routes that are 3.6 m (W8) or more, probably enough for two layers.
There are many urban passenger transport systems, such as light rail, tram and PAT (PRT), which use dedicated tracks or guideways.
The passenger demand tends to be very uneven, with peaks of passenger demand at certain times of the day leaving the system under used for the rest of the time. The major part of the investment in these systems is in the tracks, so it would make a lot of economic sense if the tracks could be exploited more intensively by using it to carry freight as well as passengers at times of low passenger demand.
Freight transport is normally incompatible with passenger transport. SSACs overcomes this because they can be moved rapidly to avoid holding up passengers and can be easily moved away from the location of passenger stations.
We propose a novel class of transport modes based on a single line of SSACs.