Robots work together

Tom Shelley reports on first commercial applications and the potential shown by collaborating robots.

By moving in swarms or flocks, co-operating robots can collect items and deliver them in an optimum order for loading or incorporation into products. Much of the development has been for military purposes, to improve communications between motor vehicles so as to improve traffic flow and reduce accidents, to work together to find things and as pure research, to create robotic football teams that compete in the annual 'Robocup', being held this year in Singapore . Dr James McLurkin, who is an assistant professor at Rice University in Houston, Texas, and one of the pioneers of the idea, takes his inspiration from the insect world. "Presently, very few robots can even open a door, while a cockroach that has been knocked over is able to recover its position in 27ms." With this in mind, the success of insects working together and flocks of birds flying together has encouraged him and other researchers to develop robots that can work in groups. In the case of his robots, they communicate with each other by infra-red links and with their central programming computer by low power wireless. They also have cameras and force feedback from a chip sensor, so they can be used to move towards something and push it. Dr McLurkin said his team is moving towards a manipulator system. Much of Dr McLurkin's research has focused on creating network trees and implementing distributed algorithms. These enable the robots to act as a group. An example task could be performing a joint search, useful when trying to quickly locate somebody trapped in a building. Dr McLurkin has also demonstrated that it is possible to get the robots to arrange themselves in a particular order, and it is this capability that has enabled Kiva Systems in Massachusetts to develop its revolutionary warehouse storage and retrieval system. The Kiva Mobile Fulfillment System consists of units that can engage shelved storage pods from underneath and then carry them around. Instead of being stored in static shelving or carousels, products are stored in pods in the centre of a warehouse, while operators stand at inventory stations around the perimeter. When an order is received, the robots retrieve the appropriate pods and bring them to the worker, who picks out the appropriate item and places it in a carton. Completed orders are stored on separate pods, ready to go and be moved to the loading dock in an optimum order when the delivery truck arrives. The items can also be stored dynamically, in order that fast-moving items can be stored in a way that allows them to make the fastest possible journeys to the person doing the picking. The system could be used in automated industrial manufacturing, but it presently seems to be finding greatest favour with US online mail order companies. Recent users include: Diapers.com and Saks Direct, which recently purchased 60 robots and 1500 storage units. Both Dr McLurkin's robots and those developed by Kiva Systems were designed using SolidWorks.