PROBLEM TO BE SOLVED: To provide a four wheel mobile robot capable of getting over a step difference such as an end of a cord and a carpet of a floor surface where there is slight irregularity.SOLUTION: The four wheel mobile robot comprises: free wheels 1, 3 disposed on front and rear positions drive wheels 2, 4 disposed on left and right positions a main frame 7-1 of the four wheel dolly which is formed into a diamond shape, in which part of the main frame 7-1 is divided as a sub frame 7-2 including the adjacent free wheel 3 and the drive wheel 2 and an oscillation rod 8 extended from the main frame 7-1, in which the sub frame 7-2 is coupled to the oscillation rod 8 using a bearing in a state that the sub frame 7-2 is capable of oscillating.COPYRIGHT: (C)2015,JPO&INPIT【課題】多少の凸凹がある床面の電気コ-ド、カ-ペットの端部等の段差乗り越えを自在とする4輪式移動ロボットを提供する。【解決手段】前後に自在輪1、3、左右に駆動輪2、4菱形に配した4輪式台車の主フレーム7-1の一部を、隣り合う自在輪3、駆動輪2を含むサブフレーム7-2として分割し、主フレーム7-1から伸ばした揺動ロッド8に軸受けを用いてサブフレーム7-2を揺動可能に連結した。【選択図】図2
