06-04-2012, 04:41 PM
Modeling and Simulation of 5 DOF Educational Robot Arm
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INTRODUCTION
Robotics is a relatively young field of modern technology
that crosses traditional engineering boundaries.
Understanding the complexity of robots and their
applications requires knowledge of electrical engineering,
mechanical engineering, systems and industrial engineering,
computer science, economics, and mathematics. New
disciplines of engineering, such as manufacturing
engineering, applications engineering, and knowledge
engineering have emerged to deal with the complexity of the
field of robotics and factory automation [1].
ROBOT DESCRIPTION
AL5B robot arm has 5 directions of motion (DOF) plus a
grip movement (5+1). It is also similar to human arm from
the number of joints point of view. These joints provide
shoulder rotation, shoulder back and forth motion, elbow
motion, wrist up and down motion, wrist rotation and gripper
motion.
AL5B has five rotational joints and a moving grip. Joint
1 represents the shoulder and its axis of motion is z1. This
joint provides a rotational q1 angular motion around z1 axis
in x1y1 plane. Joint 2 is identified as the Upper Arm and its
axis is perpendicular to Joint 1 axis. It provides a rotational
q2 angular motion around z2 axis in x2y2 plane.
KINEMATICS
Many methods can be used in the direct kinematics
calculation. The Denavit-Hartenberg analyses is one of the
most used, in this method the direct kinematics is
determinate from some parameters that have to be defined,
depending on each mechanism. However, it was chosen to
use the homogeneous transformation matrix. This
transformation specifies the location (position and
orientation) of the hand in space with respect to the base of
the robot, but it does not tell us which configuration of the
arm is required to achieve this location [3].
SOFTWARE
The first step in this process is to design the arm in
AutoCAD 3D program. The program chosen for this was
Autodesk Inventor. Inventor allows the arm to be designed
and visualized at the same time. It also allows the arm to be
checked for possible collisions and link interference.
Because each link depends upon the previous link, the design
of the arm needs to begin at the base and finish at the end
effector or gripper.
CONCLUSIONS
A complete Kinematics analysis of the AL5B robot arm
was investigated. Graphical User Interface (GUI) was
developed to test and simulate the motional characteristics of
the Robot arm. A physical interface between the AL5B robot
arm and the GUI will be designed.
The developed system will be identified as an educational
experimental tool; it can be used in graduate and
undergraduate robotic courses to realize the relationships
between theoretical and practical aspects of robot
manipulator motions in real time.