How the SSAC might work

This page aims to give an impression of what the SSAC might look like and how it might be moved around and attached to the various transport modes.

The details of the mechanisms are presented only to illustrate what might be needed. No claim is made that they would work in practise and no claims are made of ownership of intellectual property. As far as the author is aware and concerned, all the material on this site is in the public domain.

Design objectives

The design of SSAC should:

• be simple, cheap and robust
• operate in adverse weather conditions
• have no mandatory safety-critical moving parts
• have features that allow it to be mechanically constrained in all directions all the time
• can be moved in all three dimensions with mechanical control of movement
• can be attached strongly and precisely to various transport modes
• the strong attachment can be transferred from one carrier to another without letting go
• can also be handled without special equipment i.e. picked up by a fork-lift truck and placed on a flat floor.

Shape

 The blue area in the top plan view shows the full height floor area on which two 1.0 x 1.2 m pallets would be loaded.

Attachment features

There are attachment features along the bottom edges at the sides and the ends. Both incorporate runners and a series of epicyclic notches arranged so that the SSAC can move on a series of fixed wheels. These wheels can optionally have rollers that engage with the notches to provide complete control of the movement. The figures shows how this works.

 Click on the figures for animation.

There is a groove running above the rail into which an optional fixed restraint can project into it, without touching. which will prevent the SSAC from being lifted off the rails or blown off in high winds.

This restraint can be pulled down against the bottom surface of the groove to clamp the SSAC restrained in all degrees of freedom.

These features can be used by one mechanism to move the SSAC into position and then allow a different mechanism to engage with the same feature but in a different position, to clamp the SSAC onto a vehicle or for moving vertically.

 The cut-out at either end of th SSAC along the bottom corner can also be used for lifting by a fork-lift.

Finally there are four load bearing pads near the corners on which the SSAC can stand on any reasonably flat surface.

Moving the SSAC

The two pairs of rails are incorporated along the bottom corners allows the SSAC to be moved controllably in the sideways and lengthways direction. The next three figures shows how they are used for unloading and sorting them automatically. Click on images to see them animated.

 
Lifting the SSAC off a carrier. Note that the purple SSAC is heavier than the blue one and depresses the carrier suspension further. The vertical movement of the mechanism takes up this difference.  

 
Sorting SSACs on an array of fixed wheels.