American multinational retail corporation Walmart filed a patent application in March 2016 for a system which allows shopping trolleys to drive themselves and assist customers with their shopping in store. The patent was published by the US Patent and Trademark Office (USPTO) on 8 September 2016.
The shopping trolleys will be fitted with a camera, sensors and a detachable motor. According to the patent application an available shopping trolley can be called to a customer, navigate the store using its sensors and abandoned trolleys will be able to return to the docking station.
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