Design and fabrication of a microprocessor-based industrial Robot control system

Abstract

Industrial automation is characterized by periods of rapid change in automation techniques. From historical viewpoint, the origin of industrial robots is linked to the continued development of automated machinery. The concept of automation refers to the ability of a machine to perform a given sequence of tasks and meet certain specifications automatically. For machines such as robots, greater path accuracy is highly desired for their reliable operations. As a consequence, refinements in robot control systems have been a subject of many researchers in robotics technology with a view of helping to boost robots' trajectory accuracy. This idea has been motivated by the advent of microprocessors and their applications as control elements. This thesis presents the design of such a control system based on Intel 8085A microprocessor for control of an industrial robot with three degrees of freedom. The industrial robot model arm was fabricated from aluminum sheets and coupled to three-12VDC permanent magnet stepping motors to give the required degrees of freedom. The arm is trained by the user using 8-key keypad switches connected to the micro-controller system through Port B of the 8255A PPI. The command inputs from the keypad keys are stored sequentially in RAM cells for automatic control of the arm. To control the arm automatically, the user changes the mode select switch from train mode to auto mode and then presses the reset button. A detailed block diagram of the hardware and flow chart of the software monitor program modules are given and described. The whole system presented has innumerable over other types of industrial robot control systems as explicitly illustrated in the report.