Page 81 - Robotics and AI class 10
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For example, consider a robot equipped with ultrasonic sensors on its front. When the robot activates the
ultrasonic sensors, they emit sound waves that propagate forward. If an object is in close proximity to the robot,
the sound waves will bounce back sooner, indicating a shorter distance. Conversely, if the object is farther away,
the sound waves will take longer to return.
Ultrasonic sensors are commonly used for proximity sensing, obstacle detection, or even navigation in robotics.
They are particularly useful in environments where there may be obstacles or objects at varying distances from
the robot, such as indoor navigation or collision avoidance.
• Infrared Sensors: Infrared (IR) sensors use infrared light to detect the presence and proximity of objects. These
sensors emit infrared light and measure the reflection or intensity of the light when it interacts with objects. It
is based on the reflected or detected light, the sensor can determine the distance to the object. For example,
consider a robot equipped with infrared proximity sensors on its sides. When the robot activates the sensors,
they emit infrared light that is directed towards nearby objects. The sensors then measure the intensity of the
reflected light. If an object is closer, the reflected light will be stronger, indicating a shorter distance. If the object
is farther away, the reflected light will be weaker.
Infrared sensors are commonly used for proximity detection, object detection, or line following in robotics. They
are often employed in applications such as wall following, maze navigation, or detecting the presence of objects
for robotic manipulation.
Both ultrasonic and infrared sensors provide range and proximity detection capabilities to robots, allowing them
to perceive and interact with their environment. These sensors provide crucial information about the distance
to objects, enabling the robot to make decisions and execute tasks effectively while avoiding collisions or
maintaining safe distances.
Motion Sensor
A motion sensor is a type of sensor that detects movement or changes in the environment. It provides information
about the presence, direction, or speed of motion, enabling robots to detect and respond to movement in their
surroundings. Motion sensors play a crucial role in robotics for applications such as motion detection, tracking,
navigation, or human-robot interaction.
Let’s explore two examples of motion sensors commonly used in robotics: Passive InfraRed (PIR) sensors and
optical encoders.
• Passive InfraRed (PIR) Sensors: Passive infrared sensors detect changes in infrared radiation emitted by objects.
They are often used to detect human or animal movement. PIR sensors consist of one or more pyroelectric
sensors that detect the heat energy radiated by living beings and objects.
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