## double pendulum motion interpolation
###INTRODUCTION
A robot is a machine to execute different tasks repeatedly with high accuracy. Thereby many functions like collecting information and studies about the hazardous sites which is too risky to send human inside. Robots are used to reduce the human interference by nearly 50%. Robots are used in different types like fire fighting robot, metal detecting robot, etc. The first robotic arm to be used in an automobile industry was “UNIMATE” in GM motors USA in the 1950s. From then, there has been enormous improvement in the research and development in robotics. Now robots are an integral part of almost all industries. Robots have to do different tasks including welding, trimming, picking and placing.
###Working principles and working structures
A 2 DOF robotic arm has two links which works like a double pendulum. The double pendulum undergoes chaotic motion. Math theories like Lagrangian formulation for the dynamics can be used to calculate the position. The motion of the pendulum is governed by a pair of coupled differential equation. So the 2 DOF robotic arm is built in such a manner so as to reach a given co-ordinate and calculate its angle. There are 2 co-ordinates namely x and y. The link will move to that point in a specific time which is controlled by ARDUINO programming and its angle is displayed on the GIU. The motor is used to move the link to the given position.