US Patent 10198710 System to determine a change in weight at a load cell

Various sensors may be used to gather information about items at an inventory location, such as items on a shelf. Weight sensors may be used to gather weight data while capacitive sensors detect the presence of one or more objects such as the items themselves, a user reaching towards the shelf, and so forth. Data from a capacitive sensor may be used to determine that an activity is taking place at the shelf and to trigger processing of weight data from the weight sensor. A combination of a change in capacitance that exceeds a capacitance threshold and a change in weight that exceeds a weight threshold may be used to determine an event, such as a pick or place from the inventory location.