Method for handling malfunctioning vehicles on a track system and a storage and retrieval system using such a method

Abstract

A method handles malfunctioning vehicles on a track system constituting part of a storage and retrieval system configured to store a plurality of stacks of storage containers. The track system forms a grid pattern of adjacent cells. The storage and retrieval system includes a plurality of remotely operated vehicles configured to move laterally on the track system, wherein each of the plurality of remotely operated vehicles comprises driving wheels, and a control system for monitoring and controlling wirelessly movements of the plurality of remotely operated vehicles. The control system performs at least the following steps by wireless data communication: detecting an anomaly in an operational condition of a vehicle on the track system, registering the vehicle with the anomalous operational condition as a malfunctioning vehicle, registering a halt position of the malfunctioning vehicle relative to the supporting track system, and setting up a two-dimensional shutdown zone on the track system. The setting up a two-dimensional shutdown zone on the track system includes a malfunctioning vehicle zone including the halt position of the malfunctioning vehicle, and an entrance zone for entry into the malfunctioning vehicle zone. The entrance zone extends between the malfunctioning vehicle zone and a location at a periphery of the track system. The control system further performs ordering the remotely operated vehicles in operation within the shutdown zone to either move out of the shutdown zone, a halt or a combination thereof, and indicating allowance of entry into the entrance zone for an external operator by at least one of: unlocking a gateway at the periphery, and producing an entry-allowed signal registrable by a human operator located at the periphery such that the human operator may enter the entrance zone through the gateway.