Asset following method

PROBLEM TO BE SOLVED: To provide a method for searching multiple movable assets for following. SOLUTION: The data of identification mark(ID), position, strength of a storage battery and quality of signal from each following device 10A-10D, which are fitted to each asset, is received by a central station 18, and a table, which includes ID, position, strength of the storage battery and quality of the signal of each following device 10A-10D, is sorted and maintained by the central station 18. The central station 18 sorts the following devices among the table, and discriminates the following devices in a group, which are arranged close to each other, and sorts the following devices in each group so as to discriminate the following device in the group, which has an allowable strength of the storage battery and allowable quality of a signal, and sets a moving local area network of the assets to be followed between the plural following device in each group, and each following device forms node of the moving local area network. At this stage, the following device in the group, which has the allowable intensity of the storage battery and the allowable quality of signal, is assigned as a master device, and other following devices of the group are assigned as a slave device. COPYRIGHT: (C)1997,JPO