detailed information and design of robotic arm

1. APEEJAY STYA UNIVERSITY
Course- PRODUCT DESIGN DEVELOPMENT
Portfolio Report
Topic:- Robotic Arm
Submitted by: Submitted To:
Pallab Chowdhury Prof.Chetan Bharadwaj
Kanishka Dubey

2. Robotic Arm
A robotic arm is a robotic manipulator, usually programmable, with similar functions to a human arm. Servo
motor is used for joint rotation. It has about same number of degree of freedomas in human arm. Humans
pick things up without thinking about the steps involved.In order for a robot or a robotic arm to pick up or
move something,someone has to tell it to perform several actionsin a particular order — from moving the
arm, to rotating the “wrist” to opening and closing the “hand” or “fingers.” .So, we can control each joint
throughcomputerinterfaceSome advancedrobotarmsmake use of sensorslike motionandpressure sensors
in order for it to detect foreign obstacles and avoid breaking or dropping what it is carrying. Robot arm also
vary withthe type of end effectorthatthey are using.The kindof endeffectorthat a particularrobot arm is
using is very much dependent on the kind of task the robot is designed for:
1. Blowtorches for auto assembly lines robots.
2. Drills for metal application robots.
3. Spray paints for decoration oriented robots.
4. For welding purpose.
5. For pick and place applications.
Fig.1 | solid works model of our Robotic Arm

3. 1.1 Specifications our robotic arm is having following features and specification.
1. Degree of Freedom: 5
2. Payload Capacity (Fully Extended): 100gm
3. Maximum Reach (Fully Extended): 25cm
4. Rated speed (Adjustable): 0-0.3 m/s
5. Joint speed (Adjustable): 0-60 rpm
6. Hardware interface: USB
7. Control Software: computer interface (GUI)
8. Shoulder Base Spin: 180°
9. Shoulder Pitch: 180°
10. Elbow Pitch: 180°
11. Wrist Pitch: 180°
12. Wrist spin: 180°
13. Gripper Opening (Max): 8cm
1.2 Salient Features
1. The arm has six servoswhichare controlledthroughthe use of onlyone microcontrollerAtmel Atmega16.
2. The arm could grab thingsapproximatelyina hemisphere of 50cm and is robust made completelywithan
aluminium sheet of 2.5mm.
3. The armisveryuserfriendlybecauseof the computerinterface developedbyus,evenlaymancouldoperate
it.
4. It can lift objects up to weight of 100 gm.
5. The base is equipped with high torque servo.
6. The GUI isplatformfree anddoesn’trequire anytool likeMATLAB.A single setupfile thatcanbe executed
on any both windows operating system i.e. 32/64 bits.
7. The controllinghardware isusingUSBthatmakesitultra-portable.Unlike tothe old systemsof serial ports.
8. Keepingthe designof roboticarmgrippersimple,aswellasimplementingthe grippingmechanismwithout
using gears and with one servo motors.
9. The gripper is equipped with micro servo which makes it lighter.

4. Objective
The mainobjectivesof the projectare (1) tobe able todesignandconstructa robot arm, and(2) tobe able to
control the robotarmusingacomputerthroughakeyboardandmouse.The firstobjectisverystraightforward
it requires the modern designing capacities. The complete robotic arm was first designed and assembledin
designingsoftware.We have usedWildfireSolidworks todesign3Dmodelof the robot.The modelisdesigned
as perthe actual dimensionsof the robot. Afterdesigning andassemblingthe robotin Solidworks,Drawings
are exported. Our objective is to construct physical parts of the robot and them assemble them as we
assembled in the solidworks. The second objective requires a working knowledge of PC to hardware
communication.Additional hardwarecomponentsaside fromthe robotarmlike optisolatorcircuitsandlimit
switches will be implemented in order to facilitate the safe control of the arm.
Anadditional objective willbe toprogramthe robotarmtodo a simple task.Thisoption,if tobe implemented
with accuracy and precision, requires a more challenging task of familiarizing the science of kinematics both
forward and reverse kinematics.However, the implementationused for the automation of this robot arm is
time-based.Thismeans thatwhenautomatingthe robotarm, aprogramrecordsthe lengthof time of acertain
joint from moving from one position to another. This kind of automation, however, is not very accurate or
precise since it doesn’t take into consideration the actual load that the arm is carrying.
Methodology
The following block diagram explains working of the system, later we shall discussall of the componentsof
the diagram.
Fig .2 | Blockdiagram

5. Parts designing and assembly
1) Arm 1
2) Arm 2

6. 3). Base
4) Arm support

7. 5) Pin
6) washer