Amazon is working on a wristband that tracks the movements of workers across its warehouses.

The ultrasonic bracelet can precisely track where warehouse employees are placing their hands and use vibrations to nudge them in a different direction. The aim here is to streamline the fulfilment of orders, although concerns will undoubtedly be raised over excessive surveillance in the workplace.

One patent’s description reads that time-consuming acts would be eliminated, “such as pushing a button associated with the inventory bin or scanning a barcode associated with the inventory bin.” The patent was filed in 2016 by Jonathan Cohn, a senior technical programme manager for Amazon Go, which recently opened in Seattle.