Research On Key Technology And System Development Of The Aerial Fir Truck Jib Control

Aerial fire truck is an extremely important part of modern fire-fighting equipments, as it plays a significant role in high-altitude fire fighting, human rescuing, as well as in normally project engineering. Based on investigation on several styles of aerial fire truck products, we find there generally exists the fact of shaking heavily, poor balance in jib luffing process. If the situation can't be improved, it will lead to a direct influence on the stability of the operation of aerial fire truck. Thus it will decrease property of the whole vehicle, and influence its efficiency, what's worse, it may lead to a safety accident. Thus, it is urgent and full of reality importance to do a research and settle down the stability problem during the jib luffing process.The main work of this dissertation is as follows.1. A multi-body model of the jib mechanism was set up first. Then kinematics simulation was done by adopting ADAMS kits to get its kinematics characteristics. The simulation results shows that there exists a relationship between the jib luffing process's stability and the speed of jib driving hydraulic cylinder piston rod. Under particular moving speed, the jib can get better luffing stability. In the case of double cylinder driving, synchronization accuracy of the two hydraulic cylinders will have a great influence on jib luffing stability.2. Strategies and methods for synchronization control of the aerial fire truck jib driving cylinders were investigated. The electrohydraulic control system for jib driving cylinders was designed based on the proposed control strategies. Mathematical models of each part of the system were set up and the whole system was simulated under MATLAB/Simulink environment. The simulation results have shown that the control system is stable and owns high synchronization control accuracy, which can fulfill the needs on jib luffing stability.3. Through analyzing principles and realization methods for CDQ24aerial fire truck jib luffing control system, combined with the relationship between the speed characteristics of the piston rod and the jib luffing stability, the main reason which leads to poor jib luffing stability lies on its control system cannot adjust the hydraulic piston rod's moving action according to special speed characteristics.4. Test model for motion control of the aerial fire truck was set up by adopting the former research results. The model was used to implement the control strategies for testing. The test results shows that the research results gain in this dissertation is correct, practical and feasible.