Study On Trajectory Planning Of Folding Boom Aerial Work Platform

Aerial work platform through the space movement of the work platform to complete equipment installation,maintenance and other work,for the aerial work has brought great convenience.With the wide application of aerial work platform,it will also face more complex operation scenarios.As the traditional manual control will lead to the problems of poor stability and low operating efficiency of aerial work platform,higher requirements will be put forward for the intelligent degree of aerial work platform.The research of trajectory planning is of great significance to improve the intellectualization of aerial work platform.In this paper,the folding boom aerial work platform as the research object,on the basis of the robot theory,the trajectory planning problems of aerial work platform are studied,including: kinematics analysis,joint space trajectory planning,work space special trajectory planning and the shortest time trajectory optimization.The specific research contents of this paper are as follows:(1)According to the structural characteristics of the boom system of the folding boom aerial work platform,the mathematical model of the boom system of the aerial work platform is firstly established by using D-H method,and the forward and inverse kinematics equations of the aerial working vehicle are deduced.The correctness of the kinematics equations is verified based on the Robotics Toolbox.Then,the joint space,driving space and working space of the aerial work platform are introduced,and the nonlinear relation between the joint space of the boom and the driving space is deduced.Finally,on the basis of kinematics,the motion range of the work platform in the workspace is solved by Monte Carlo method.(2)For trajectory planning of aerial work platform in joint space,three trajectory planning methods are firstly studied: polynomial interpolation,spline curve interpolation and three piece-wise polynomial interpolation of 3-5-3,4-3-4 and 4-2-5.Then,different trajectory planning algorithms are used to simulate the spatial path points of the second boom joint in MATLAB,and the kinematic performance of the second boom joint under different trajectory planning methods is compared.(3)The trajectory planning of the work platform in the workspace is carried out.Firstly,the linear and circular interpolation algorithm based on S-type velocity planning is used to carry out the trajectory planning of the work platform,which ensures the stability of the work platform.Then the Jacobian matrix of the aerial work platform is derived,and the movement of the work platform is transformed into the joint movement of the boom.Combined with the mapping relationship between the joint space and the driving space,the trajectory planning from the movement of the work platform to the movement of the driving cylinder is realized.Finally,four special trajectories of the work platform are simulated in MATLAB: vertical straight line,spatial straight line,horizontal circle and spatial circle.(4)Taking the shortest time as the optimization objective,the particle swarm optimization algorithm is used to optimize the 4-3-4 and 4-2-5 piecewise polynomial interpolation trajectories of the boom joint space under the constraints of velocity and acceleration of the boom joint.The time optimal trajectories of the two piecewise polynomial interpolation methods are compared,and the feasibility of the time optimal algorithm is verified.