Abstract: Robot manipulator is an essential motion subsystem component of robotic system for positioning, orientating object so that robot can perform useful task. The main objectives of this project are to design and implement a 4-DOF pick and place robotic arm. This project can be self-operational in controlling, stating with simple tasks such as gripping, lifting, placing and releasing. In this project, the focus is on 4-DOF articulated arm. Articulated arm consists of revolute joints that allowed angular movement between adjacent joint. Four servo motors were used in this project to perform four degree of freedom (4-DOF). There are numerous dimensions over which robotic arms can be evaluated, such as torque, payload, speed, range, repeatability and cost, to name a few. Robot manipulators are designed to execute required movements. Their controller design is equally important. The robot arm is controlled by a serial servo controller circuit board. The controller used for servo motor actuation is ATmega 16 Development board.

Keywords: picks and place, 4-DOF robotic arm, manipulator, gripper, Servo motor, AT mega 16.

1. INTRODUCTION

The field of robotics has its origins in science fictions. The word robot comes from the Czech word "robota" means forced labor in 1920. It took another 40 years before the modern technology of industrial robotics began. Today, robots are highly automated mechanical manipulators controlled by computers. A robot may appear like a human being or an animal or a simple electro-mechanical device. A robot may act under the direct control of a human (e.g. the robotic arm of the space shuttle) or autonomously under the control of a programmed computer. Robots may be used to perform tasks that are too dangerous or difficult for humans to implement directly (e.g. nuclear waste cleanup) or may be used to automate repetitive tasks that can be performed more cheaply by a robot than by the employment of a human (e.g. automobile production) or may be used to automate mindless repetitive tasks that should be performed with more precision by a robot than by a human (material handling, material transfer applications, machine loading and unloading, processing operations, assembly and inspection).[4]

The last two decades have witnessed a significant advance in the field of robots application. Many more applications are expected to appear in space exploration, battlefield and in various actives of daily life in the coming years. A robot is a mechanical device that performs automated tasks and movements, according to either pre-defined program or a set of general guidelines and direct human supervision. These tasks either replace or enhance human work, such as in manufacturing, contraction or manipulation of heavy or hazardous material. Robot is an integral part in automating the flexible manufacturing system that one greatly in demand these days. Robots are now more than a machine, as robots have become the solution of the future as cost labor wages and customers demand. Even though the cost of acquiring robotic system is quite expensive but as today's rapid development and a very high demand in quality with IS0 standards, human are no longer capable of such demands. Research and development of future robots is moving at a very rapid pace due to the constantly improving and upgrading of the quality standards of products.[3]

1.1 PROBLEM STATEMENT:

To solve the problems of pick and place the cylindrical object having 6 cm diameter and 150 gram weight from one conveyor to another at room temperature in order to reduce human efforts and efficient material handling. The distance between two conveyers is 50 cm.

2. DESIGN OF ROBOTIC ARM

The mechanical construction in this project is to build and assemble the robotic arm body. After giving a thorough consideration of all the preceding works in this field, a four degree of freedom manipulator having variable programmed motions to carry out variety of tasks in perse environments is chosen. This is a four axis articulate manipulator designed to move material like machine parts, tools, specialized devices, etc. It is driven by four servomotors and has a gripper as end-effectors. The gripper has fingers grasping and manipulation of objects as big as a 150 ml cylindrical bottle and having a weight of about 150 gm throughout the arm’s workspace.