Designing and Controlling the Movement of an Object via Cables at Space

Abstract

The aim of this project is to design and implement a control system for controlling the three dimensional movement of an object within a selected working space. The trajectory of motion is guaranteed by three cables connected to the object, the length of these cables are controlled by three independent DC motor that receive their commands from a PC-computer, the user gives only the target position through the keyboard, the computer will compute the trajectory and controls the cables' lengths as function of time to achieve the desired target position with the planned trajectory. The length of the three cables is measured by three absolute rotary encoders attached to the driving pulleys at the motor. Knowing the lengths of three cables leads to computing the (x,y,z) coordinate of the controlled object this is done by utilizing the forward kinematics equation of the system. The proposed controller for each degree of freedom is PID controller, in order to achieve the transient and steady state performance of the controlled system.In addition to the control algorithm design, the synergistic system integrates theelectrical system, computer system and mechanicalsystem of the overall prototype in mechatronics system approach.