Cooperative Hoisting with Dual Crawler Cranes under Motion Constraints

With the continuous development of industries such as wind power and construction, the weight and complexity of lifted equipment have significantly increased. These lifting tasks often rely on crawler cranes, and the demand for cooperative lifting using dual crawler cranes has grown. However, current operations remain largely manual, leading to safety risks and low efficiency. While extensive research has been conducted on the coordination of overhead cranes and other lifting systems, studies on cooperative control of crawler cranes are still in their early stages and have received insufficient attention. To address this issue, this paper establishes an accurate model of a dual crawler crane system using Lagrange equations. Motion constraints are incorporated to reduce the original fifth-order dynamics to a third-order system, simplifying control implementation. Given the strong coupling characteristics of the underactuated system, a PID-based coupled error compensation control method is proposed to regulate the load's position and attitude precisely. By coordinating cable length adjustments, the proposed method ensures stable and accurate positioning while guaranteeing finite time convergence of cable length errors. Finally, a wind turbine installation scenario is simulated to validate the effectiveness of the proposed control approach.