Are Robots Taking Over our Warehouses?
8th December 2016 | Peter Baker
Dr Peter Baker, co-author of The Handbook of Logistics and Distribution Management, discusses robots as they apply to warehousing
There has been much talk of robots taking the place of humans in warehouses for many years. In fact some commentators may argue that, with the advent of timed processes, labour management systems, performance monitoring and radio data terminals, many warehouse operatives are already expected to work like robots. Thus real robots may well be much better suited to many of the current warehouse tasks – with humans planning their deployment in accordance with constantly varying demand patterns.
Automation has of course been fairly widespread in warehouses for many decades now, covering such areas as:
- Automated storage and retrieval systems for the storage of pallets
- Miniload systems for the storage of cartons and tote bins
- Automated guided vehicles (AGVs) for the movement of goods
- A-frame dispensers for order picking small cartons
- Advanced conveyor and high-speed sortation systems
- Automated packing machines, pallet loaders, and vehicle loading systems
However, can any of these actually be classified as being a robot? An industrial robot is defined by ISO 8373 as: ‘An automatically controlled, reprogrammable, multipurpose manipulator programmable in three or more axes, which may be either fixed in place or mobile for use in industrial automation applications’.(1) It could be argued that all of the equipment types mentioned above are automatically controlled and reprogrammable. However, some are not programmable in three or more axes and it is doubtful whether any are truly multipurpose.
More recently, there have been a number of new equipment types that have been introduced under the name of ‘robots’. One that has gained quite a lot of publicity is the shelf modules-to-picker system using robotic drive units (also known as ‘bots’ or robotic butlers) to bring shelf modules (say about one metre in length and comprising about two to five shelves in height) to a picking station for manual picking. Amazon, for example, have adopted this type of system in a number of their U.S. warehouses. Another is based on a multi-level grid system whereby tote bins are stored in vertical columns in a grid frame and accessed by multi-wheeled robots running along the top of the frame. These extract the required tote bins and take them to ports at the edge of the grid for onward movement to a picking station. There are also robotic fork-lift trucks which can put away and extract pallets to and from racking. These are similar in many ways to AGVs, but also have a lifting capability. Similar trucks are used to transport pallets along pick faces so that order pickers do not have to drive picking trucks during a pick route.
Examples of robots with arms include robotic picking machines which use grippers or suction pads to pick up items. Improvements in 3-D vision systems are making these technically more feasible. As with the options of picker-to-goods or vice versa in manual solutions, there is the decision of robot-to-goods or goods-to-robot with this equipment. A similar application found in warehouses is that of robotic palletisers which can stack tote bins onto wooden pallets or onto dollies (wheeled platforms).
Even though these are all called robots, it is doubtful whether they all fully meet the ISO 8373 definition, particularly with regard to being ‘multipurpose manipulators’ - with the possible exception of some robotic picking machines and palletisers. However, most people probably use a similar definition to one that I found on the internet from a ‘computer guru’: ‘I can’t really define robot. I just know one when I see it.’(2) Thus, the answer as to whether or not robots are taking over our warehouses is probably in the eye of the beholder.
You can find details of all this equipment plus, of course, the more conventional storage and handling equipment found in warehouses in the latest edition of The Handbook of Logistics and Distribution Management.
(1) ISO: International Organization for Standardization.
(2) Gordon McComb (amateur robotics guru): http://www.bowlesphysics.com/images/Robotics_-_A_historical_perspective.pdf