PROBLEM TO BE SOLVED: To provide an automatic steering system in which a control overshoot is restrained.SOLUTION: An automatic steering system of a work vehicle includes: a steering traveling device for performing counter-clockwise turning, based on an amount of steering to the left direction on the basis of a neutral position, and performing clockwise turning, based on the amount of steering to the right direction on the basis of the neutral position； an own vehicle position calculation unit 55 for calculating an own vehicle position； a positional displacement calculation unit 57 for calculating positional displacement from a travel path and the own vehicle position； a vehicle body direction calculation unit 56 for calculating a vehicle body direction showing the direction of a vehicle body； a directional displacement calculation unit 58 for calculating directional displacement from the travel path and the vehicle body direction； a steering amount calculation unit 41 for calculating a steering amount for solving the positional displacement and the directional displacement, based on the positional displacement and the directional displacement； and a steering amount restriction part 42 for restricting the steering amount calculated by the steering amount calculation unit 41, based on a current steering amount.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2019,JPO&INPIT【課題】制御オーバーシュートが抑制される自動操舵システムを提供する。【解決手段】作業車の自動操舵システムは、中立位置を基準とする左方向への操舵量に基づいて左旋回を行い、中立位置を基準とする右方向への操舵量に基づいて右旋回を行う操舵走行装置と、自車位置を算出する自車位置算出部５５と、走行経路と自車位置とから位置ずれを算出する位置ずれ算出部５７と、車体の向きを示す車体方位を算出する車体方位算出部５６と、走行経路と車体方位とから方位ずれを算出する方位ずれ算出部５８と、位置ずれと方位ずれに基づいて、位置ずれ及び方位ずれを解消するための操舵量を算出する操舵量算出部４１と、操舵量算出部４１によって算出される操舵量を、現状の操舵量に基づいて制限する操舵量制限部４２を備えている。【選択図】図６
