3DOF drawing robot using LEGO-NXT

This paper presents a 3 DOF robotic arm used for drawing on a paper sheet. The robotic arm is constructed using LEGO NXT bricks. The purpose of the development was to create a control system of the servo motors for the robot, as well as the inverse kinematics, used for moving the arm. The NXT controller is running LejOS for optimal motor control, while inverse kinematics is being calculated on a PC connected to the NXT via bluetooth. The robotic arm is well applied in education projects about robotics and robot programming.