Abstract: An item dispensing system includes one or more inventory drawers, at least one of the inventory drawers comprising one or more inventory tracks configured to hold items. At least a given one of the inventory tracks comprises a drive assembly comprising a motor and a sensor assembly affixed above a front of the given inventory track proximate an item drop region of the item dispensing system. The drive assembly is configured to controllably advance the items held in the given inventory track towards the item drop region, and the sensor assembly is configured to detect vending of items from the given inventory track to the item drop region using at least one light emitter and sensor. The item dispensing system also includes an item dispensing system controller configured to control the motor and monitor signals from the sensor to determine whether the given item has dispensed.