Abstract:Taking unmanned aerial vehicle (UAV) hydraulic launch system with bladder accumulator as main power supply, pulley block as growth mechanism as research object, the working principle of the system launch phase was introduced, a new method was proposed to analyze pulley block modeling, the simplified model of the system was established, and the mathematical model of the system was deduced by using bond graph method. Based on a practical system for simulation, the changing characteristic curves of the hydraulic cylinder intake chamber pressure and speed of UAV and sliding dolly were gotten. The method feasibility is proved by analogy, which provides theoretical guidance for the design and research of similar system.