The self-checkout system has been sold by an Canadian company called Optimal Robotics Corp. since 1995. The cost of the systems varies wildly from location to location. The price is usually set so that the retailer should see a return on the investment within the year. That money comes in the form of labor savings and increased throughput. The systems are usually set up in blocks of four, and they're not completely human-free.
Consumers clearly have a lot of questions when using the checkouts.
The systems use a standard scanner. Placing the item in the bag is a critical part of the operation. The carousel is hooked up to weight sensors and has a database that tells the system what each product scanned should weigh. If the weight doesn't match the item, the system knows there's a mistake someplace. The system also has a video camera that seems pretty sophisticated.