Detection method and device for suspension arm, controller and engineering machinery

The embodiment of the invention provides a detection method, a detection device, a controller and engineering machinery for a suspension arm. The detection method for the suspension arm comprises the following steps: obtaining a reference surface, wherein the reference surface is determined based on the positions of a plurality of track points in the motion track of the top end of the suspension arm in the pitching motion process of the suspension arm in the sidewise bending-free state; determining that the suspension arm is in a to-be-detected state; acquiring the position of the top end of the suspension arm in the to-be-detected state; and determining sidewise bending state information of the suspension arm according to the position of the top end of the suspension arm and the reference surface. According to the embodiment of the invention, the sidewise bending of the suspension arm can be automatically and accurately measured. 本发明实施例提供一种用于吊臂的检测方法、检测装置、控制器和工程机械，所述用于吊臂的检测方法包括：获取基准面，其中所述基准面是基于所述吊臂在无旁弯状态下的俯仰运