Automatic Control Systems for Construction Machinery

Automatic control systems for construction machinery have been developed, which control the motion of attachments. The purpose of these systems is to simplify such difficult operations as level crowding of a hydraulic excavator and level luffing of a crawler crane. The control systems consist of a microcomputer-based controller, sensors and hydraulic actuators. The nonlinear characteristics of hydraulic actuators and low rigidity of structure of construction machinery make it difficult to achieve high control accuracy and high stability performance. A control algorithm was developed to solve the problem for these systems and the validity of the algorithm has been verified by operating tests. The control algorithm has been verified by operating tests. The control algorithm has been verified by operating tests. The control algorithm has is the combination of feedback control, feedforward control, nonlinear compensation and gain modification.