Abstract: Items may be stored at an inventory location using an instrumented hook system. The instrumented hook system may include a hook from which items may be suspended. The hook may be affixed to a support arm using a weight sensor. The weight sensor provides weight data indicative of the weight of items suspended by the hook. The system may also include other sensors such as capacitive sensors, photodetectors, image sensors, and so forth. Sensor data from these sensors may be used to determine interaction data indicative of a quantity on hand, quantity picked, quantity placed, and so forth.

Abstract: Sensors at an inventory location can be used to detect the occurrence of an event at the inventory location. For example, capacitive sensors can gather capacitance values, which can then be analyzed for changes that indicate an event has occurred at the inventory location. When an event has been detected, event data is generated and used as a possible trigger to collect additional sensor data. As an example, if an event involving items at an inventory location is detected, such an action can trigger the collection and analysis of additional sensor data, such as weight sensor data, to determine a quantity of the items added or removed from the inventory location.

Abstract: A user may pick, place, or move an item at an inventory location, such as a shelf. Described are techniques to determine a location of one or more of an object, such as an item or a user, with respect to an array of capacitive sensors. The array may be part of the shelf. As an item is added to, moved or removed from the shelf, when the user's hand is near the shelf, and so forth, capacitance measured by one or more of the sensors in the array may change. Based on these changes, a location relative to the sensor array may be determined. A particular shelf may have different areas, each designated as holding a different type of item. The location information obtained from the capacitive sensors may be used to determine which item on the shelf was interacted with.

Abstract: 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.

Abstract: Capacitive sensors may be used to gather information, such as the presence of objects at an inventory location, such as a shelf. Two or more adjacent capacitive sensors operating at the same time may interfere with one another. Described are techniques to prevent this interference by using seed values to initialize pseudo random sequencing of an order in which capacitive sensors are in operation. The capacitive sensor, or a portion thereof, may be also be used as an antenna. Selection of an initial tuning network for use by the antenna may be determined based on output from the capacitive sensor.