Method and apparatus for sorting articles using a matrix of conveyor cells

An efficient package sorting system in which a stationary matrix of multi-directional conveyor cells sorts packages to a plurality of destination locations. In a preferred embodiment, the matrix delivers sorted packages to a plurality of lift assemblies that further transfer the packages to receiving conveyors or chutes on different levels. According to another preferred aspect of the system, a selectively elevating stop bar is provided to control side transfer between conveyor cells. A controller is operative to plan a path for each of the objects from the input cell to a destination location, to monitor availability of successive conveyor cells along the path, and to cause an object to be moved to the next conveyor cell along its path only when the next conveyor cell is available. The system may include a plurality of sensors positioned to sense the passage of objects from one conveyor cell to another, the sensors being connected to the controller. The sensor input is used to guide the packages through the matrix, and to optimize the speed at which a plurality of packages can be sorted.