FABRICATION OF A 5 D.O.F ROBOT ARM CONTROLLED BY HAPTIC TECHNOLOGY

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FABRICATION OF A 5 D.O.F ROBOT ARM CONTROLLED BY HAPTIC TECHNOLOGY 1 NITHIN RAJAN, 2 V.MANOJ KUMAR 1 Graduate Student, 2 Ass. Professor SRM University E-mail: Nitz.719@gmail.

The paper specifically aim to develop a low cost Five degree of freedom Robot arm controlled using Haptic Technology.

1 FABRICATION OF A 5 D.O.F ROBOT ARM CONTROLLED BY HAPTIC TECHNOLOGY 1 NITHIN RAJAN, 2 V.MANOJ KUMAR 1 Graduate Student, 2 Ass. Professor SRM University Nitz.719@gmail.com, vmanojkumar19@gmail Abstract- Robotic Surgery is developing very fast in terms of technology. The paper specifically aim to develop a low cost Five degree of freedom Robot arm controlled using Haptic Technology. Robotic Arm using haptic technology can be implemented for medical application in developing and under developing countries. A 5 DOF robot arm is designed which motion tracks a human operator's arm motion including open-close hand tracking by the end-effector. The work is exclusively focused on the controlling of the robot arm using the Accelerometers and Gyroscope. The accelerometer gives the position and the gyroscopes gives us m the orientation of the hand movement, so the appropriate movement of the robot arm can be made in accordance with the human movement. The value s from the Acclerometers and Gyroscope is converted into corresponding angle of rotation to the servo s in the model. Keywords- D.O.F-Degree of freedom,c.a.d-computer Aided Design I. INTRODUCTION The Haptic robotic arm is investigating robotics as smart as a human operator, a new phase in human-robotic interact-ability. Potential applications a simpler programming interface, industrial applications and as well as hazardous situations. Haptic technology, or haptics, is a tactile feedback technology which takes advantage of the sense of touch by applying forces, vibrations, or motions to the user. This mechanical stimulation can be used to assist in the creation of virtual objects in a computer simulation, to control such virtual objects, and to enhance the remote control of machines and devices (tele-robotics). Haptic devices may incorporate tactile sensors that measure forces exerted by the user on the interface. The accelerometer and gyroscope make the motion analysis of the human operator and these motions are directed to a embedded robotic arm system. Also the Haptic Robot arm is an exteroceptive control system activated depending upon stimulus input which received from human. More simply, the human operator provides spontaneous control feedback of the human-robot interactive system. The present system of robot arm control is made by means of human arm motion. The future applications includes the control of robot arm by leap sensors, programmer s sensor jacket, Kinect Sensors.etc[1][2][3] The future of robotics in manufacturing and assembly is increasing flexibility both in mechanical performance and ubiquitous integration with human workers. The future of robotics is greater dexterity, easier and quicker response Programmability, and safe operation with human co-workers. Building a tele-operated master-slave robot arm driven by sensors worn on a human arm is investigating future possibilities and general performance considerations of advanced robotics. II. MECHANICAL DESIGN OF ROBOT ARM The Mechanical Design includes the Model crested in the Solid Work and the Material Selection from the calculated Torques for each joints A. CAD Model Design A CAD Model was developed using Solidworks Software.The model has 5 Degree of freedom Robot. The Arm lengths for different joints were chosen as o The base axis located at coordinate (0,0,0) with 9cm o The height of the shoulder joint is 7.5cm above coordinate (0,0,0) o The length of the under arm is 12.1cm o The length of the upper arm is 15.5cm o The length of the wrist links is 5.5cm o The length of the gripper is 10cm 92

2 B. Material Selection To find the appropriate material to be used for fabrication, the Volume, Mass and Torque of different materials calculated and the comparison of the material which is suitable is chosen. The material chosen for comparison are the following a. Acryl b.al alloy c.plywood The Volume of the material is calculated according to the profile approximately and tabulated in Table 2.1 a. Acryl-1.2*10^-3 b.al Alloy-2.7*10^-3 C.Plywood-0.56*10^-3. The Densities of different joints is then tabulated in Table 2.3 Table:2.1 Volume Calculations The Mass Calculation of the different materials are calculated as the following Table:2.2 using the formula. DENSITY= MASS/VOLUME Similarly Torque for different joints were found different materials. The Densities of the materials are given below. (in gm/mm^3) Fig: 2.2 Skeleton Model of Robot Arm 93 Torque Calculation for the robot arm designed is

ELECTRONIC DESIGN The Basic electronic design of the Robot Arm consist of mainly two sections Transmission Section Receiver Section Elbow= (Mass of the Upper Arm)* L3/2 (Mass of the Wrist links and

3 calculated by the following the skeleton of the robot arm in the Fig 2.2[5] Gripper= (Mass of the Gripper)*L1/2 Wrist=(Mass of the Wrist links and GripperPlate)*L/2+(Mass of the Gripper)* (L1/2+L2)+(Mass of the Gripper Motor)*L2 III. ELECTRONIC DESIGN The Basic electronic design of the Robot Arm consist of mainly two sections Transmission Section Receiver Section Elbow= (Mass of the Upper Arm)* L3/2 (Mass of the Wrist links and GripperPlate)*(L2/2+L3) + (Mass of the Gripper)*(L1/2+L2+L3) + (Mass of Gripper Motor)*(L2+L3) + (Mass of the Wrist Motor)*L3 Shoulder =(Mass of the Under Arm)*L4/2+(Mass of the UpperArm)* (L3/2+L4) +(Mass of the Wrist links and Gripper Plate)*(L2/2+L3+L4)+(Mass of the gripper)* (L1/2+L2+L3+L4)+(Mass of the Gripper Motor)* (L2+L3+L4)+(Mass of the Wrist Motor)*(L3+L4)+(Mass of the Elbow Motor)*L4 The Table shows the Torque for different materials in kgcm units in Table: 2.4 Acrylic Material was chosen for the following reasons. o Cost is less compared to other two materials. o Speed of all motors remains same to maintain Required torques o Tensile Strength is greater than that of Plywood but less than that of Aluminum Alloy. As per the calculated Torque the motor selection is done which is available in the market. C.Fabricated Model For the Fabrication of the Model the different parts was made using Laser cutting device with Acrylic sheet of 4mm thickness. The Fig: 2.3 shows the Fabricated Model. In this Transmission Section utilizes the Arduino UNO Board and Arduino MEGA Board on the Receiver Section using the ZigBee Technology. The ZigBee Technology will transmit signals wirelessly which makes the Robot Arm Motion as that of Human Hand without any external help. Accelerometer and Accelerometer + Gyroscope were connected to Human Hand to make the necessary motion on the Robot arm in Real time Scenario. Two joints were connected with accelerometers and one joint with Accelerometer+ Gyroscope. The Shoulder Joint gives the information of base rotation (X-axis) and Under Arm rotation (Y-axis).The Elbow Joint gives the Upper Arm rotation (Y-axis).The Wrist Joint gives the Pitch movement (Y-axis) as well as the Roll Movement using the Accelerometer+ Gyroscope. In addition to Accelerometer and Acceleremeter + Gyroscope Module, a Flex Sensor was attached to the finger for the opening and closing of the Gripper.[4] The Accelerometer module and Accelerometer + Gyroscope used in this work is of MMA7361L and MPU-6050 respectively. The Transmitter Section and Receiver Section is shown in Fig: 3.1 and Fig: 3.2 respectively. Fig:-3.1 Transmitter Section 94 Fig:-3.2 Receiver Section

IV. SIMULATION OF THE MODEL The Simulation of the whole project was achieved by using PROTEUS 8.0 and that of Robot Arm Simulation was done by using MATLAB. The Fig4.

As the Proteus Software does not contain the ZigBee Library a Virtual Com Port is used for Wireless Communication.

Here forward kinematics and inverse kinematics of the model is done using MATLAB software.[5] I.

The end effector of the robot arm is the gripper. In order to solve this problem a model of the robot arm needs to be made.

With joint angles that need to be variable.

the DH convention is used for deriving the Forward Kinematics of the model.

The figure above shows the Robot Arm position for The Robot Arm Simulation was done using MATLAB Software as shown in Fig 4.2.

4 IV. SIMULATION OF THE MODEL The Simulation of the whole project was achieved by using PROTEUS 8.0 and that of Robot Arm Simulation was done by using MATLAB. The Fig4.1 above shows the PROTEUS Simulation of the whole Project which consist of a Arduino Uno R3 for the Transmitting Section and Arduino Mega 2560 for the Receiver. As the Proteus Software does not contain the ZigBee Library a Virtual Com Port is used for Wireless Communication. Similarly the Accelerometer cannot be implemented, so the Potentiometer is used for this purpose. derivatives of the position variables. Here forward kinematics and inverse kinematics of the model is done using MATLAB software.[5] I. Forward Kinematics Forward kinematics is the problem of locating the position and orientation of the end effector, with given joint angles. The end effector of the robot arm is the gripper. In order to solve this problem a model of the robot arm needs to be made. In this model there has to be a relationship between the individual joints of the robot arm and the position and the orientation of the end effector. With joint angles that need to be variable. For making this model a convention needs to be chosen for selecting frames of reference for the different links of the robot arm.the DH convention is used for deriving the Forward Kinematics of the model.[5] By using the Robotic Toolbox in MATLAB the Forward Kinematics of Robot Arm of different position can be simulated. The figure above shows the Robot Arm position for The Robot Arm Simulation was done using MATLAB Software as shown in Fig 4.2. The Solis Work Design was converted to XML format using the SimMechanics Interface and Then the XML is converted into Simulink Model using the SimMechanics command mech_import. The Servomotor control is made for the actuation of each of the joints.inorder to vary the at specified angles sliders were in between the Servo and Simulink model. V. ANALYSIS OF THE MODEL A. Kinematic Analysis Kinematics is the description of motion without regard to the forces that cause it. It deals with the study of position, velocity, acceleration, and higher II. Inverse Kinematics The problem of inverse kinematics is in general more difficult than the forward kinematics. With the inverse kinematics find the joint variables for a given position and orientation of the end link. This is very important 95

5 for finding the forces in every joint when the robot arm needs to move to a certain point.[5] B. Real Time Analysis The Fabrication of a 5 degree of Freedom Robot Arm which is controlled by haptic technology was done. This work contains immense application in the ongoing research fields such as Robotic Surgery, Bomb Identification and disposal, Robotic Spacecraft, Warfare. Artifical Intelligence can also be implemented in the current model of Robot Arm to reduce the dependency of human and also an additional internet based control of Robot Arm can be made. REFERENCES The Figure shows the Motion Analysis of the model was done MATLAB Software. A Separate Arduino UNO Board was set up in order to read Servo motor rotation angles from the Arduino MEGA 2560 Board. The Arduino Package is downloaded as Add-ons in MATLAB and utilizing the Simulink Model created the Real Time Analysis of the model is done. CONCLUSION [1] DANIELA TARNITA,DAN B. MARGHITU, ANALYSIS OF A HAND ARM SYSTEM,ROBOTICS AND COMPUTER-INTEGRATED MANUFACTURING, DECEMBER 2013, VOL 29, P.P [2] ENDO, T. KAWASAKI, H.,MOURI, T., ISHIGURE, Y., SHIMOMURA, H., MATSUMURA, M., KOKETSU, K. FIVE-FINGERED HAPTIC INTERFACE ROBOT: HIRO III IEEE TRANSACTIONS ON HAPTICS, 17 DECEMBER 2010,VOL:4, PP [3] OBLAK, J., CIKAJLO, I., MATJACIC, Z., UNIVERSAL HAPTIC DRIVE: A ROBOT FOR ARM AND WRIST REHABILITATION NEURAL SYSTEMS AND REHABILITATION ENGINEERING, 20 OCTOBER 2009 VOL18, PP [4] Jing Zhao,Biyun Xie, Chunyu Song, Generating human-like movements for robotic arms, Theory November 2014, Vol -81, P.P [5] R.K Mittal and I.J Nagrath ROBOTICS AND CONTROL Textbook of Tata McGraw Hill. 96

WIRELESS VEHICLE WITH ANIMATRONIC ROBOTIC ARM

WIRELESS VEHICLE WITH ANIMATRONIC ROBOTIC ARM PROJECT REFERENCE NO. : 37S0918 COLLEGE : P A COLLEGE OF ENGINEERING, MANGALORE BRANCH : ELECTRONICS & COMMUNICATION GUIDE : MOHAMMAD RAFEEQ STUDENTS : CHARANENDRA