Performance Analysis Of Adaptive Non-Singular Fast Terminal Sliding Mode Control For Motion Control Of A 3-Dof Delta Parallel Robot

Abstract

A Delta Robot Is A Type Of Parallel Mechanism That Consists Of Three Arms Connected In A Common Base. Parallel Robots Have More Accuracy Because They Do Not Have Cumulative Joint Errors. Further Advantages Of This Robot Are Low Inertia And High Stiffness. Further More, The Delta Robot Is Composed Of Four Main Parts Such As, Base, Arm, Forearms And End Effector. The Arms Of The Delta Robot Perform Motions In A Solitary End Of Arm Tooling (EOAT), Within A Workspace That Is Dome Shaped. This Type Of Robot Is Well Known In The Industrial Field For Its Ability To Execute Minute, Precise Motions. Delta Robots Can Be Called Other Names In The Industrial Field, Such As Spider Robots Or Parallel Robots.The 3-D Model Of A 3-DOF Delta Robot Is Designed In 3D-CAD (Solidworks). Hence, This Modeling Environment Enables To Introduce Real But Not Approximated Parameters Of The Robot And Eased Computation Of Large Matrixes. Dynamical Model With All The Kinematic Constraints For A Robot Will Simply Be Found By Exporting A 3D-CAD Model Of The Robot To Simscape Multibody. A Mathematical Model Of 3-DOF Delta Robot Has Been Carried Out, Based Upon The Application Of The Newton-Euler Equations Of Motion Used In Conjunction With The Jacobian Matrix To Map The Inertial And Gravitational Loadings Of The Moving Plat Form To The Actuators.This Thesis Presents An Adaptive Nonsingular Fast Terminal Sliding Mode Control Al Gorithm With A Modified Switch Function For A 3-DOF Delta Robot Manipulator With Un Known Modeling Errors And External Disturbances. The Finite Time Convergence Of The Con Troller Is Analyzed Using Lyapunov Stability Theory. The Algorithm Avoids The Singularity Problem Of The Traditional Terminal Sliding Mode Control And The Slow Convergence Of The Traditional TSM Control And Estimates The Upper Bound Of System Uncertainties. A Modified Switch Function Is Used To Achieve Precise Tracking And Reduce Chattering In Control Torque. Finally, The Effectiveness Of The Control Method Is Verified Through Simulation.The Performance Of The Controller Is Tested By Tracking A Circular Trajectory Centered At (0, 0, Z0) On XY- Plane With 10 In Radius. The Simulation Result Shows That The Steady State Tracking Is Reached In Less Than 2 Seconds For A Circular Trajectory And X And Y Rms Error Of 0.01 In.