Page 140 - Toucpad robotics C11

6. Write a short note on the role of controllers in a robotic system.
Ans. Acts as the robot’s brain—processes sensor input, runs logic, and sends signals to actuators.

B. Long answer type questions.
1. Explain in detail the working of a DC motor and its applications in robotics.

Ans. Works on electromagnetic principle—current through coil produces rotation. Used in wheels, fans, conveyor
belts in robots.

2. Describe servo and stepper motors, comparing their advantages and disadvantages.
Ans. ∑ Servo: High precision, angle control, feedback system, but costly.
∑ Stepper: Moves in fixed steps, no feedback, simple control, but can lose steps under load.
3. Discuss the importance of feedback in closed-loop systems with examples.
Ans. Ensures accuracy—e.g., cruise control in cars adjusts speed by feedback from sensors. Without feedback,
errors accumulate.

4. Explain the role of sensors (IR, Ultrasonic) in enabling robots to interact with their environment.
Ans. IR detects heat/obstacles, Ultrasonic measures distance. Together, they help robots “see” and respond to
their environment.
5. With a neat diagram, explain how actuators, sensors, and controllers work together in a robotic system.
Ans. Sensors collect data 'Controller processes it' Actuators execute tasks. Example: In an obstacle-avoiding
robot, ultrasonic detects object, controller processes, motor turns wheels.

Sensor Controller Actuator
(Measure process (Decision Making) (Takes action to
variable) control)

21 st
C. Competency-based questions: HOTS Century #Digital Literacy
Skills
1. You are designing an obstacle-avoiding robot. Which sensors and control system would you use? Justify
your choice.
Ans. Use ultrasonic sensors for distance detection, IR for close obstacle sensing. A closed-loop control system
ensures continuous feedback for accuracy.

2. A factory wants a robotic arm that can rotate precisely to fixed angles for packaging. Which motor would you
recommend and why?

Ans. A servo motor is best—it allows precise angular rotation (e.g., 30°, 90°, 180°) needed for packaging tasks.

Unsolved Questions
SECTION A (Objective Type Questions)
QUIZ
A. Tick ( ) the correct option.
1. Which actuator would you use for a robotic arm that needs precise angular positioning?

i. DC motor ii. Servo motor
iii. Stepper motor iv. Pneumatic cylinder

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