Question

1. which sensor would you use to help the robot stop near a wall?

a. shaft encoder
b. bumper sensor
c. limit switch
d. ultrasonic sensor

Explanation:

To determine the sensor for stopping a robot near a wall, we analyze each option:

• A. shaft encoder: Measures rotational position/speed of motor shafts, not for proximity to walls.
• B. bumper sensor: Detects physical contact (collision), so it triggers when the robot hits the wall, not "near" it.
• C. limit switch: Similar to bumper, activates on physical contact, not for proximity.
• D. ultrasonic sensor: Emits ultrasonic waves and measures reflection time to detect distance. It can sense the wall from a distance, allowing the robot to stop "near" the wall before contact.

Answer:

D. ultrasonic sensor