Research On Pneumatic System Control Of An Aircraft Skin Detection Robot With Double Frames

With the rapid development of aviation technology,the amount of aircraft grows rapidly.The detection problem of plane has been also got more and more attention of people.In this thesis,we need to decrease the problem of the manual inspection which contains big labor intensity,long test cycle,and high rate of missed detection according to the requirement of intelligent detection for aircraft skin.In this paper,a kind of double framework aircraft skin detection robot has been studied.According to the control of the robot pneumatic system,the theoretical analysis and comprehensive experiments have been carried out.First of all,the influence of aircraft skin curvature on robot adaptability has been discussed.The robot adsorption stability influences from inclination angle of suckers,structure parameters of robot and radius of curved surfaces are analyzed.Through the analysis of the force on the curved surface,the critical conditions for the safety and stable operation of the robot are derived.The influence of those relevant parameters on adsorption force of the robot is analyzed by simulation,which provides a theoretical basis and reference for further improving and optimizing the structure of the robot.Then,the positioning control of the robot’s legs has been studied.A sliding mode variable structure control method based on nonlinear observer is designed and realized the positioning control.Based on the positioning control of the robot’s legs,the attitude adjustment strategy is proposed for robot locomotion gait.Through the adjustment strategy,the security and adaptability of the aircraft skin detection robot is guaranteed.In addition,based on the fluid network theory,the adsorption system of robot is studied.The sucker’s vacuum state change of adsorption and release has been researched.The advantages and disadvantages of traditional switching strategy are analyzed according to the change of vacuum state.A flexible strategy based on PWM is discussed,which made the theoretical analysis for the following experiments.Finally,the experiment on vacuum adsorption system of the robot has been researched.The changes of vacuum state caused by different switching strategies such as direct switching,rigid switching and flexible switching are analyzed with two different environment of plane and inclined plane.At the same time,the stability and reliability of the robot are analyzed.