CONSTRUCTION MACHINE WITH A CONTROL SYSTEM FOR THE SUPERSTRUCTURE

A control system for a construction machine that can stop an upper swing structure at a desired swing stop angle is provided. A main controller includes: a swing stop target angle setting section that sets a swing stop target angle that is a target angle at which an upper swing structure is stopped; a swing control section that outputs a drive command to a control valve in such a manner that a speed reduction of swing of the upper swing structure is executed; a swing stoppability determination section that reads an angle signal of the upper swing structure with respect to an undercarriage detected by a first angle sensor and an angle signal of a work implement detected by a second angle sensor, and that determines whether the swing of the upper swing structure can be stopped at the swing stop target angle on the basis of these signals; and a work implement control section that outputs drive command signals to control valves in such a manner an extension action of the work implement in a swing radial direction is prohibited or a contraction action of the work implement in the swing radial direction is executed in response to a signal that indicates whether the swing can be stopped and that is determined by the swing stoppability determination section.