摘要 |
Disclosed is a crane comprising: a lower body; an upper slewing body; a counterweight unit including a plurality of wheels to travel on the ground in a turning direction equal to a slewing direction of the upper slewing body while being suspended from the upper slewing body; a steering actuator for rotating each of the wheels around a steering-rotation center axis to change the steering angle; and a steering control device for controlling the steering actuator. The steering control device includes: a slewing-identification-signal receiving section which receives a slewing identification signal for identification of the slewing direction of the upper slewing body; and an actuator operating section operates the steering actuator to orient each of the wheels to the inside of a tangent line to an orbit of the wheel at the steering-rotation center axis, based on the identified slewing direction identified from the slewing identification signal. |