If you ever despair of having a tidy desk then help is now at hand.

US scientists have invented a smart table that can sort and rearrange almost anything put on it.

The development may lead to bar counters that take drinks to customers, or restaurant tables which automatically arrange cutlery, crockery and cruets into place settings.

The ultimate result of the research could be programmable rooms that can rearrange furniture without the help of humans.

PhD student Dan Reznik and Professor John Canny of the computer science department at the University of California, Berkeley, have developed the table.

The pair has discovered that by vibrating a table many times per second they can move the objects sitting upon it.

The device has been given the grand name of a universal planar manipulator.

Table-top tricks

The table is shaken using motors positioned on two adjacent sides of the table, which move it in one of two directions. Anyone looking down on the table would see that the motors could vibrate it either North-South or East-West.

The motors shake the table via small rods that touch it near three of its corners. By combining vibrations applied from the different directions, the academics have found that they can shuffle objects placed on the table surface.

The control system for the table uses algorithms developed by the academics over the last four years. These reveal how the table should be shaken to move an object to a particular position.

The vibrations whip the table out from under the objects that then, thanks to friction, come to rest a tiny distance away from their initial position.

By repeating this many times a second, focusing on a different object every time, it is possible to move separate objects in different directions and even divide up groups of objects.

Object lesson

The researchers have demonstrated the table's prowess by showing how it can make three pennies follow a bow tie shape, make another penny trace out the shape of a plus sign and sort a random scattering of eight poker chips by their colour.

Sitting over the table is a camera that records the position of all objects on the table so the control system can work out how close they are to their destination.

Mr Reznik and Professor Canny have designed a graphical interface for the table which shows what is on it and lets people tell the table where to move the objects with the click of a mouse.

The first prototype of the smart table was a baking tray, but now the researchers are using an aluminium honeycomb that transmits the vibrations better and is less likely to turn them into useless vertical movements.

Future work will involve speeding up the movement of objects and making bigger tables.

Mr Reznik has presented his work at several academic conferences over the last couple of years but news of the smart table was first reported on the US technology news site Wired.