Design and test of a real-time shelf out-of-stock detector system

The shelf out-of-stock (SOOS) problem is relevant for retailers and producers since the absence of products on the shelf can lead to a significant reduction of shoppers and a consequent drop on sales. For this purpose, it is necessary to study and introduce approaches able to measure and prevent the lack of products on the shelves and thereby promptly ensuring their refill. In this context, the paper describes the design of an embedded wireless sensor network able to detect in real time a shelf out-of-stock event. In particular, we present a shelf detector sensor based on a novel, low cost and low power wireless sensor network design that can automatically discover out-of-stock in a shelf for all the stores of a retail chain. The use of an automatic method for detecting products not available on the shelf is the first being installed for a long time in a high number of stores. This paper aims to present the hardware infrastructure of the embedded sensor network devoted to real time shelf out-of-stock management and to demonstrate the feasibility and the scalability of the system discussing interesting results about scalability, long life battery based installations and data analysis.