Research On Dual-mechanism Action Coordinated Control Of All-terrain Crane

All-terrain crane is used in the construction of modern large-scale projects, because the crane possesses the advantages of mobile flexible, cross-country ability and compact structure. The low intelligence of large tonnage all-terrain crane reduces the efficiency of the installation of the crane on-site operation and demands higher technology of worker’s installation. The diversity of the boom combination of the large tonnage all-terrain crane boom and uncertainties of the site make challenge for the control of main arm telescopic with the tower arm condition. To avoid the dangerous working conditions, improve reliability and operational safety of the all-terrain crane, the main arm telescopic with the tower arm condition uses manual control at construction site. This reduces the efficiency of the installation of the tower arm condition, increases the investment in human resources and requires high technological skills of site operators. To solve the problems above, this paper establishes the main arm telescopic and the tower arm luffing simulation model with MATLAB/Simulink and analyzes the control effect of different control methods. In this paper,the research content is as follows:(1) The structure and composition of the all-terrain crane tower arm condition as well as different boom-lifting process for the main arm are described; the difficulties in dual mechanism of cooperative control are analyzed.(2) The control module of the main arm telescopic and the tower arm luffing hydraulic system is derived and the precise control model is established. According to the geometry of the crane coordinate relations, the tower arm angle value is derived in different main boom length and tower boom luffing length.(3) The different characteristics of the hydraulic system modeling methods are analyzed and the main arm telescopic and the tower arm luffing hydraulic system with the transfer function method are established. The stability of the two hydraulic systems is analyzed through frequency domain analysis method.(4) MATLAB/Simulink software is used to establish the simulation model of the hydraulic system, dynamic analysis of system response characteristics through time-domain analysis method. Quantitative feed-forward compensation composite correction link is added to the system to eliminate the steady state error with ramp response. (5)Factors affect the system control precision are analyzed and simulation effects of parallel control, master-slave control and cross-coupled PID control method are proposed. Simulation results show that, the application of master-slave control and cross-coupled PID control, the system’s cooperative control can achieve better control effect.