The next time you pack your bags at the supermarket checkout, give yourself a small pat on the back. A task which is so simple for humans - quickly and efficiently packing a bag of groceries of different sizes and shapes without crushing anything - is something that until recently has been beyond the abilities of robots. It requires vision systems to locate the produce, a flexible and strong hand to grab items and a sophisticated artificial intelligence which knows that a carton of eggs should not be stacked under a four-pint bottle of milk. It is a problem that James Matthews, the chief executive of Ocado Technology (part of the Ocado Group) is wrestling with in the warehouses that handle online orders. The company has a sophisticated warehouse in Erith in east London, which is already highly automated.