AUTOMATIC STEERING SYSTEM

To provide an automatic steering system which does not require a front-wheel steering angle detection mechanism for mechanically detecting a steering angle of front wheels.SOLUTION: An automatic steering system comprises a steering unit ECU for controlling a steering unit on the basis of a position and orientation of a traveling machine body 1 that are measured with a positioning system. The steering unit ECU comprises means for calculating an estimated steering angle, that calculates a vehicle speed V and an angular velocity ω of the traveling machine body on the basis of the position and orientation of the traveling machine body that are measured by the positioning system, in order to calculate an estimated steering angle φ of the traveling machine body on the basis of the calculated vehicle speed V and angular velocity ω. The estimated steering angle φ calculated by the means for calculating an estimated steering angle is used to feedback-control the steering unit.SELECTED DRAWING: Figure 4 【課題】自動操舵システムにおいて、前輪の舵角を機械的に検出する前輪舵角検出機構を不要とする。【解決手段】測位システムが計測した走行機体１の位置及び方位に基づいて操舵ユニットを制御する操舵ユニットＥＣＵを備える自動操舵システムであって、操舵ユニットＥＣＵは、測位システムが計測した走行機体の位置及び方位の変化量に基づいて走行機体の車速Ｖ及び角速度ωを算出し、且つ算出した車速Ｖ及び角速度ωに基づいて走行機体の推定舵角φを算出する推定舵角算出手段を備え、推定舵角算出手段が算出した推定舵角φを使用して操舵ユニットをフィードバック制御する。【選択図】図４