robotics 2mark

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SELVAM COLLEGE OF TECHNOLOGY, NAMAKKAL DEPARTMENT OF MECHANICAL ENGINEERING SUBJECT: INDUSTRAIL ROBOTICS SEMESTER / YEAR : VII / IV Prepared by, I.Sirajudeen, Asst. Professor, Department of Mechanical Engineering Checked & Verified by, S. Malik Raj, Professor & Head of Dept, Department of Mechanical Engineering

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Page 1: Robotics 2mark

SELVAM COLLEGE OF TECHNOLOGY, NAMAKKAL

DEPARTMENT OF MECHANICAL ENGINEERING

SUBJECT: INDUSTRAIL ROBOTICS

SEMESTER / YEAR : VII / IV

Prepared by,

I.Sirajudeen, Asst. Professor,

Department of Mechanical Engineering

Checked & Verified by,

S. Malik Raj,Professor & Head of Dept,

Department of Mechanical Engineering

Page 2: Robotics 2mark

Unit-I:

1. Name the FOUR basic robot configurations.a) Cartesian coordinate systemb) Cylindrical coordinate systemc) Polar or spherical coordinate systemd) Revolute coordinate system

2. List out the types of joint Notation.(a) Linear joint,(b) Rotational joint,(c) Twisting joint,(d) Revolving joint.

3. What is meant by a work envelope?The work envelope is described by the surface of the work space. It depends upon the number of types

of joints, physical types of joints and links and the range of various joints.

4. Sketch a robot and name its parts.1. Manipulator (Robot arm)

2. End effector

3. Controller

4. Gripper

5. Actuator

5. What is meant by workspace?The space in which the end point of the robot arm is capable of operating is called as workspace in

other words, reach ability of robot arm is known as workspace.

6. What is meant by degeneracy? Some robots, though, do have a certain joint arrangement in their final orientation joints that can

lead to redundancy for certain orientations. Most industrial robots have 6 or less joints, thus, redundancy is not inherent to their design.

7. List the various types of robot drive system for industrial robots1. Electric drive:

(a) DC motor; (b) Servomotor; (c) Stepper motor2. Pneumatic drive3. Hydraulic drive

8. Sketch and indicate the type of any rotating joints used in robots. (or) Sketch a twisting joint. Rotational (R):

9. What are the types of hydraulic actuators used in robotics?(i) Piston cylinder, (ii) Swing motor, (iii) Hydraulic motor

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10. What is meant by robot anatomy? The robot anatomy is the study of structure of robot that is physical construction of the manipulator's

structure. The mechanical structure of manipulator that consists of rigid bodies (links) connected by means of

joints, is segmented into arm that ensures mobility and reachability, a wrist that confers orientation, and an end effectors that performs the required task

11. What are the three degrees of freedom associated with the arm and body motion?

Three degrees of freedom associated with the arm and

body motion are:

Right (or) Left movement (X-axis motion)

In and out movement (Y -axis motion)

Vertical movement (Z-axis motion)

12. Define the term work envelope. Work envelop is defined as the envelope (or) space within which the robot can

manipulate the end of the wrist. A robot's work envelope is the range of movement

13. Give some application of robots in industries.(a) Material Handling Application

(i) Material transfer application(ii) Machine loading/unloading application.

(b) Process Application(i) Welding(ii) Painting(iii) Assembly(iv) Machining(v) Inspection

14. How do you specify a robot?(i) Speed; (ii) Actuator(iii) Payload; (iv) Repeatability(v) Accuracy; (vi) Reliability(vii) Manipulator; (viii) End effector

-----------------------------------------------------------------------------------------------------------------------------------------------Unit-II:

1. State any two techniques used for object recognition.a) Template matchingb) Structural Technique

2. Write about Hall Effect sensors.When a beam of charged particles passes through a magnetic field forces act on the particles and the

beam is deflected from the straight line path a current flowing in a conductor is like a beam of moving charges and thus can be defined by magnetic field

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3. Classify the robots according to the drive system.1. Pneumatic drive2. Hydraulic drive3. Electric drive

(a)DC Motor(b) Servo motor(c) Stepper motor

4. List any two important advantages and disadvantages of a pneumatic gripper.Advantages of pneumatic gripper:

1. Its light weight design.2. It is possible to distribute the pressure uniformly the entire area.3. Control is simple4. Pick up time is very fast.

Disadvantages:1. It is not suitable for heavy loads.2. Sometime is required to build the pressure.

5. What is inverse Kinematics?It is a scheme to determine joint angles of robot by knowing its position in the world coordinatesystem.

Pjoint = (θ1, θ2, θ3)

6. Name any four proximity sensors used in roboticsSensor, which senses the presence or absence of the object without having physical contact between

the objectsI) Inductive Sensor2) Capacitive Sensor3) Ultrasonic Sensor4) Magnetic Sensor

7. Sketch the screw-actuated mechanical gripper.

8. What are the limitations of adhesive grippers?(i) Adhesive substances losses his tackiness on repeated usage.(ii) Reliability is diminished with successive operations

9. Distinguish between direct and inverse kinematics.(i) Reverse kinematics: It is a scheme to determine joint angles of a robot by knowing its Position in the world coordinate system.

PJOINT = (θ1, θ2, θ3)(ii) Direct kinematics: It is a scheme to determine the position of the robot in the world coordinate system by knowing the joint angles and the link parameters of the robot.

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PWORLD = ( x, y, z )

10. Differentiate between touch and force sensors.Touch sensor: It senses the presence or absence of the object by having physical contact between the

objects.Force sensors: Force sensors are used primarily for measuring the reaction forces developed at the interface between mechanical assemblies

11. List the types of drives used in robots. Electric drives Hydraulic drives Pneumatic drives

12. What is a RCC device? For what purpose is it used in a robot?RCC device means Remote. Center Compliance devices.Uses: (i) RCC device are commonly used in automated assembly applications to provide Compliance for misalignment during assembly. (ii) The compensator is a .compliance device that enhances the flexibility and reliability of a robot

13. What is a mechanical gripper? A mechanical gripper is an end effector that uses mechanical finger actuated by mechanism to grasp an

object. Mechanical grippers are used to transfer parts from one location to another or to assemble parts.

14. What is the properties 0f stepper motor? Stator wiring (number of coils and wire loads). Number of steps in a complete rotation. Operating voltage and current. Amount of force generated (torque). Maximum rotation speed (steps per second).

15. State the advantage and limitation of hydraulic drive.Advantage:

1. Robust2. Self lubrication3. It can also provide precise control at low speeds.4. High efficiency and high power to size ratio.5. Hydraulic robots are more capable of withstanding shock loads.

Disadvantage:1. Expensive2. High maintenance3. Not energy efficient4. Noisy5. Not suited for clean air environments

16. Write the basic principle of servo motor. A servomotor is used within position control (or) speed control feedback control system. An electrostatic motor is based on the attraction and repulsion of electrical charge.

17. Give some examples of robot end effector.1. Gripper2. Tools3. Welding equipment

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4. End of arm tooling

18. What are the types of grippers?'1. Mechanical finger grippers.2. Pneumatic grippers.3. Hydraulic grippers.4. Collect gripper.5. Magnetic gripper.6. Vacuum gripper.

-----------------------------------------------------------------------------------------------------------------------------------------------Unit-III:

1. Define a tactile sensor and list the types.Tactile sensor is device that indicates the contact between themselves and some other solid objects.

1. Digital (Touch) Sensor2. Analogue (Force) Sensor

2. List the two basic types of robot programming method.a. Lead through methodsb. Textual robot languagesc. Mechanical Programming

3. State the working principle of a touch sensor.Touch sensors in sensors, which senses the presence or absence of the object by having physical contact

between the objects. When the button is pressed, an electrical circuit is closed inside the sensors. This lets electricity flow. When the button is released, the circuit is broken and no electricity flows. Touch sensors send a signal when physical contact is made.

4. What is the function of a frame grabber? A frame grabber is an electronic device that captures individual, digital still frames from an analog video

signal or a digital video stream. It is hardware device used to capture and store the digital image.

5. What are the limitations of hydraulic drive systems?1) Expensive2) High maintenance3) Not energy efficient4) Noisy5) Not suited for clean-air environments.

6. What is the purpose of thresholding in analysis?Thresholding is a binary conversion technique in which each pixel is converted into a binary value either black or white.

7. Mention use of machine vision system.(i) This can be used to replace, machining for applications like welding, machining to maintain relationship between tool and work.(ii) Machine vision systems are used for printed circuit board.(iii) This is for the recognition of object from its image.(iv) Achieve 100% accuracy.

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8. Enumerate the difference between open loop and closed loop control system

Open loop control system Closed loop control system

It is being relatively simple More complex

Low cost More cost

Good reliability Greater chance of breakdowns as a

consequence of the greater number of components

The disadvantage is that they are often inaccurate since there are no correction for error

Relatively accurate in matching the actual to the required values

9. What is meant by template matching?Templates of the parts to be recognized are stored in the vision system memory. The images recorded

by the vision camera are compared with the templates stored in memory to determine if a matching part is present.

10. What is a teach pendant?The teach pendant is usually a small handheld control box with combinations of toggle switches, dials

and buttons to regulate the robot's physical movement's and program capabilities

11.Classify the position sensors.Main types of position sensors are:

Incremental Absolute

Some other devices which are used as position sensors. Resistive position sensors. Linear variable differential transformer (LVDT) Encoders. Potentiometer. Resolver

12. Brief on the working of inductive type proximity sensor. Inductive proximity sensors operate under the electrical principle of inductance. Inductance is the phenomenon where fluctuating current, which by definition has a magnetic

component induces an electromotive force (emf) is a target object. To amplify a devices inductance effect, a sensor manufacturer twists wire into a tight coil and runs a

current through it.

13. What is triangulation? Triangulation is a process by which the location of radio transmitter can be determined by measuring

either the radial distance, or the direction of the received signal from two (or) three different points. Triangulation is sometimes used in cellular communication to pin point the geographic position of a

user.

14. What is smoothing in vision system? Smoothing in vision system is often used to reduce noise within an image (or) to produce a less

pixelated image. Most smoothing methods are based on low pass filter

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15. What are the desirable features of sensor?1. Cost 2. Ease of operation3. Operating range 4. Accuracy5. Precision 6. Reliability'7. Speed of response 8. Calibration

16. List the different types of tactile sensor. Digital (Touch) Sensor Analogue (Force) Sensor

17. What are the applications of Machine Vision System? Inspection Identification Visual serving and navigation

18. What are the various techniques in image processing and analysis? Image data reduction Segmentation Feature extraction Object recognition

-----------------------------------------------------------------------------------------------------------------------------------------------Unit-IV:

1. What are Actuators? Actuators are the devices used for converting hydraulic energy (or) electrical energy into mechanical

energy. In other words, actuators perform a function just opposite to that of the pumps. The pressurized hydraulic fluid delivered by the hydraulic pump is supplied to the actuators, which

converts the energy of the fluid into mechanical energy. This mechanical energy is used to get the work done. The hydraulic actuators produce linear, rotary, or

oscillating motion.

2. What is transformation? Transformations of frames introduced to make modeling the relocation of objects easier.An object is

described with respect to a frame located in the object, and this frame is relocated with a transformation.

The transformation is the result of a sequence of rotations and translations, which are recorded with a transformation equation

3. What is meant by a teach pendent?The teach pendent is usually a small hand held control box with combination of toggle switches, dials

and buttons to regulate the robot's physical movements and program capabilities.

4. Explain any two commands associated with programming of an end effector.1. OPEN2. CLOSE.3. OPEN I4. CLOSE I

OPEN I: These instructions cause the pneumatic control valves to receive a signal to open the gripper immediately.

CLOSE I: These instruction cause the pneumatic control valves to receive a signal to close the gripper.

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5. Define the term 'feature extraction ‘Transforming the input data into the set of feature is called feature extraction. A feature area,

diameter, perimeter, is a single parameter that permits ease of comparison and identification.

6. State any two techniques used for object recognition.a) Template matchingb) Structural Technique

7. What the benefits of this off line programming? Reduced down time for programming. Programming tools make programming easier. Enables concurrent engineering and reduces product lead time. Assists cell design and allows process optimization.

8. Explain the reasons for defining points in a program. To define a working position for the end-effector To avoid obstacles

9. What is A GV?Automated guided vehicle (AGV) is an independently operated self-propelled vehicle guided along

defined pathways in the floor. It is normally powered with batteries. It is mainly used for handling material from one place to other place.

10. List out different types of image compression technique. Discrete image transforms in image data compression Hierarchical and progressive compression techniques Comparison of compression methods

11. Perform the following transformation on point (25, 10, and 20): Trans (8, 5, and 0).

Solution: Case 1:

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12. What is the command used to execute the speed of the robot in VAL programming? Speed command is used to define the velocity with which the robot's arm is moved. SPEED 90: Indicates that the robot should operate at 90% of normal speed during program execution. SPEED 50 Ips: Which indicates the speed of the end effector during program execution would be 50

in/sec.

13 .Determine the translated vector for the given vector = v = 25 i + 10 j + 20 k, perform a translation by a distance of 8 units in "x" direction, 5 units in 'y" direction and 0 units in "z" direction.

Given that: v = 25 i + 10 j+ 20 k; x = 25, Y = 10, and z = 20x direction (a) = 8 units; y direction (b) = 5 units; z direction (c) = 0 units

Solution: The translation transformation

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14. Write the meaning of the following command:DMOVE (1, 10)DMOVE (< 4, 5, 6> < 30, - 45, 90>)

Solution: DMOVE is the motion command for an Incremental (or) Delta.move. In parenthesis the joint and the distance of incremental move are specified.

Example 1: DMOVE (1, 10) Ist IInd

Ist position indicates the joint number. IInd position indicates the distance of the incremental moves. Joint 1 moves by 10 inch.

Example 2: DMOVE (< 4, 5, 6> < 30, - 45, 90>) The motion commands an incremental move of axes 4, 5, 6 and by 30°, - 45° and 90°

respectively.

15. What is reverse kinematics?It is a scheme to determine joint angles of robot by knowing its position; in the world coordinate

system.

16. Define degrees of freedomIt is defined as one of the variables required to define the motion of a body in space. Each joint in a

robotic system gives the robot one degrees of freedom.

17. Show the relation usd in forward & reverse transformation of 2degrees of freedom manipulator

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18. What is teach pendant?The teach pendant is usually a small handheld control box with combination of toggle switches, dials

and buttons to regulate the robot's physical movements and program capabilities.

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Unit-V:1. What is continuous path programming?

It is the types of programming were the motion cycle involves smooth complex Curvilinear movements of robot arm.

2. What is teach pendant?The teach pendant is usually a small handheld control box with combinations of toggle switches,

dials and buttons to regulate the robot's physical movements and program capabilities.

3.List any two important considerations for robot safety. Environmental condition. Location and installation requirement. , Human errors. Mode of operation

4. How do you calculate the robot economics by return of investment method?

5. What is the purpose of structured lighting?The intersection of the sheet with objects in the work space yields a light stripe which is viewed

through 'a television camera displaced a distance from the light source. The stripe pattern is easily analyzed by a computer to obtain range information.

6. What are the different methods of economic analysis?1) Payback method2) Equivalent uniform annual cost (EUAC) method3) Return on investment (ROI) method

7. What are the general characteristics that make potential robot application technically practical and economically feasible?

Hazardous or uncomfortable working conditionsRepetitive operationsDifficult handling jobsMulticast operation

8. What are the steps to be followed by the company in order to implement robot programs in its operations?

Initial familiarization with the technology. Plant survey to identify potential applications. Selection of the application. Selection of the robot. Detailed economic analysis and capital authorization. Planning and engineering the installation. Installation.

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9. What is meant by image analysis?Image analysis ids the collection of processes in which a captured image that is prepared by image

processing is analyzed in order to extract information about the image and to identify objects or facts about the object or its environment.

10. Give two applications of robot in machining. Drilling; Grinding; Reaming; Tapping Deburring

11. Calculate the payback period for a robot project with the following data: Net annual cash flow Rs. 45,000, Investment cost Rs. 1, 00,000

Given: Net annual cash flow = Rs. 45,000; Investment cost Rs. 1,00,000

To find: Pay back period

Solution:

12. Which data are required to perform economic analysis of a robot project? Expected rate of return. Payout and investment's expected life. Risk is not making investment. Cost and risk incase of failure. Opportunity cost that is the return from alternative investment.

13. What are the three levels of safely sensor systems in robotics defined by National Bureau of Standards?

The National Bureau of standards defines three levels of safely sensor system in robotics.Level 1 - Perimeter penetration detectionLevel 2 - Intruder detection inside the work cellLevel 3 Intruder detection in the immediate vicinity of the robot.

14. Total investment cost is estimated as Rs. 5 lakhs for a robot project. The total operating costs are expected to be Rs. 20,000 per year. The expected revenues from the robot installation are Rs. 1,00,000 annually. It is expected that the robot project will have a service life of 5 years. Determine the payback period that is expected of the investment.

Given that: Total investment cost estimated = Rs.5,00,000 Total operating cost/year = Rs.20,000 The expected revenue and from = Rs.1,00,000

the robot installation Expect service life n = 5 years

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To find: Pay back period

Solution:

15. List the typical MOTION command.1. MOVE2. APPRO3. DEPART4. DMOVE

16. List out types of A GV vehicles.1. To wing vehicles2. Unit load vehicles3. Pallet truck vehicles4. Fork truck vehicles5. Light load vehicles6. Assembly line vehicles

17. What are types of robots commonly used for machine loading and unloading operation?1. Servo control robot (point to point)2. Non-servo robot (pick and place robot)

18. Write two aspects of the safety issue in robotics.1. Redundancy2. Back up system

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