(SEM V) THEORY EXAMINATION 2024-25 ROBOTICS

Subject Code: BEE051
Maximum Marks: 70
Time: 3 Hours
Paper ID: 310947

Question Paper Overview

SECTION A (2 × 7 = 14 Marks)

(Attempt all questions briefly)

a. Write about Automation in Robotics.
b. Define the term ‘Robot’.
c. Describe SCARA robot configuration.
d. Define the term Resolution in robotics.
e. Explain about Pitch, Yaw, and Roll.
f. Discuss robots classified according to JIRA.
g. Discuss the applications of Tactile Sensors.

SECTION B (Attempt any three × 7 = 21 Marks)

a. Discuss the role of robot joints, coordinates, and reference frames in the movement and positioning of a robot.
b. Illustrate the process of transformation of matrices in robot kinematics. Explain how transformations between reference frames affect robot motion and task execution.
c. Compare hydraulic, pneumatic, and electrical actuators in terms of performance, efficiency, and suitability for various robotic applications.
d. Explain drive systems used for robotic grippers. Compare mechanical, vacuum, and magnetic grippers with their principles and applications.
e. Explain the functioning of contact and proximity sensors, and their role in robotic perception and navigation.

SECTION C (Attempt one part from each question × 7 = 35 Marks)

Q3

(a) Discuss the role of robots in Industry 4.0. How do robots contribute to automation in smart factories?
OR
(b) Given two points auvw=(4,3,2)Ta_{uvw} = (4, 3, 2)^Tauvw​=(4,3,2)T and buvw=(6,2,4)Tb_{uvw} = (6, 2, 4)^Tbuvw​=(6,2,4)T in a rotated OUVW coordinate system, determine the corresponding points axyz,bxyza_{xyz}, b_{xyz}axyz​,bxyz​ with respect to the reference coordinate system if it has been rotated 60° about the OZ axis.

Q4

(a) Discuss forward and inverse kinematics of robots.
OR
(b) Using Denavit–Hartenberg (D–H) criterion, find out the D–H table for a given robotic system and calculate H21H_2^1H21​.
Given: θ1=90°\theta_1 = 90°θ1​=90°, θ2=30°\theta_2 = 30°θ2​=30°, θ3=30°\theta_3 = 30°θ3​=30°.
(Diagram for the robotic system is shown on page 1 in the paper.)

Q5

(a) Explore how cameras and image processing systems enhance robots' abilities in inspection, navigation, and object recognition.
OR
(b) Explain rotary-to-rotary motion conversion mechanisms (like gears, belts, and cables) used in robotics with sketches.

Q6

(a) State the important steps in Denavit–Hartenberg (D–H) convention and explain its advantages.
OR
(b) Write the requirements and challenges of end effectors. Discuss different types of end effectors used in robotics.

Q7

(a) Explain the different classifications of sensors and discuss their functions in industry.
OR
(b) Explain the working of tactile sensors with a neat sketch.

Key Topics for Revision

1. Automation in Robotics

Integration of mechanical systems, sensors, and AI to perform tasks automatically.

Enhances productivity, precision, and repeatability.

Examples: automated assembly, inspection, welding, and material handling.

2. Definition of Robot

According to ISO 8373,

“A robot is a reprogrammable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks.”

3. SCARA Robot Configuration

Selective Compliance Assembly Robot Arm (SCARA):

4-axis robot with 2 parallel rotary joints providing compliance in the XY-plane.

Used for pick-and-place, assembly, and packaging operations.

4. Resolution in Robotics

Smallest incremental movement detectable or controlled by the system.

Depends on the encoder’s bit resolution and mechanical precision.

5. Pitch, Yaw, and Roll

6. JIRA Classification of Robots

Based on Joint–Interface–Reach–Application (JIRA):

Articulated robots               Cartesian robots

Cylindrical robots                Polar robots

SCARA robots

7. Tactile Sensors

Detect touch, pressure, and texture.               Types: resistive, capacitive, piezoelectric.

Used in grasping control, surface mapping, and collision detection.

8. Robot Joints and Coordinate Systems

Joints: Provide degrees of freedom (rotational or prismatic).

Coordinate Systems: Define robot and workspace positions (base, tool, joint, world).

Reference Frames: Transformation matrices define relative motion between frames.

9. Actuators

10. Grippers

Mechanical: Fingers/jaws for object holding.           Vacuum: Uses suction for flat surfaces.

Magnetic: Handles ferromagnetic materials.

11. Transformation Matrices

Used to convert positions/orientations between coordinate frames.

Fundamental in kinematics, path planning, and manipulator control.

12. Forward & Inverse Kinematics

Forward: Computes end-effector position from joint angles.

Inverse: Determines joint angles for a desired position.

Key for trajectory generation and motion control.

13. Denavit–Hartenberg (D–H) Convention

Standard method for assigning coordinate frames to robotic links.

Four parameters:

Link length (aia_iai​)                  Link twist (αiα_iαi​)

Joint angle (θiθ_iθi​)                 Joint offset (did_idi​)

Advantages: Simplifies matrix computation and robot modeling.

14. Cameras & Image Processing in Robotics

Enhance vision-based perception.

Used for object detection, navigation, and inspection tasks.

Employs edge detection, pattern recognition, and machine learning.

15. End Effectors

Types:

Grippers (mechanical, magnetic, vacuum)

Tools (welders, sprayers)

Challenges: Grip force control, object variability, alignment precision.

16. Sensors in Robotics

Exam Strategy Tips

Draw clear, labeled diagrams for D–H parameters, SCARA, and coordinate systems.

Revise matrix transformations and kinematics derivations.

Practice numerical problems on coordinate transformation and D–H tables.

Prepare short notes on sensors, actuators, and Industry 4.0 applications.