| As an important part of construction machinery, the Aerial working Platform is widely used in many fields now, and it has a broad and bright prospect for development. But the internal production technologies of Aerial working Platform are obviously lagged to other countries in this industry. Thus, based on the understanding and analysis of the development status of aerial working platforms and its key technologies, this thesis has studied and designed the control system of 27 meters Self-propelled straight arm Aerial working Platform by referring to the advanced technologies of other countries.First of all, according to the functional requirements and design requirements of Aerial working Platform, this thesis analyzes the driving system, the steering and axle stretching system, the boom telescoping and luffing system, and then designs the control programs of these systems. Secondly, in order to improving reliability and efficiency of the vehicle, the automatic control of platform vertical climbing motion is researched. Then this thesis designs the control program of vertical climbing system on the basis of analyzing the motion of telescopic boom. Mathematical model of the telescopic boom control system is builded. Digital PID control algorithm is applied in control system. And the Matlab7.11.0 is used to establish computer simulation model of the PID control system. After analyzing the character of the system, the simulation shows that the character is better than previous system. The digital PID control algorithm can obtain good control result. Thirdly considering the characteristics of high safety and reliability of the aerial work platform, this thesis establishes hardware structure by construction machinery dedicated control module-EPEC3G+CAN, including two EPEC2023 controllers and EPEC2025 display. And the pins of controllers are distributed. Finally, the communications system of control modules is builded by CAN bus technique.Then the flow charts of the control system are wrote. |
