Lesson 3: Sensors and Actuators: The Senses and Muscles of IoT

Learning Objectives Define 'sensor' and 'actuator' using analogies to the human body. Identify at least three examples of sensors and actuators in everyday smart devices. Explain the relationship between input (from a sensor) and output (to an actuator). By the end of of this lesson, students will be able to create a simple flowchart for an IoT device that uses a sensor to trigger an actuator. Write a simple 'if-then' statement in pseudocode to control an actuator based on sensor data. Differentiate between a device that senses its environment and a device that acts upon it. How does a video game controller know you're shaking it, or an automatic door know you're there? 🤔 Let's find out! In this lesson, we'll explore the &#...

TermDefinitionExample SensorA device that detects and measures a physical property (like light, temperature, or motion) and turns it into a signal a computer can read. It's like the 'senses' of a device.The temperature sensor in a smart thermostat 'feels' how warm or cold a room is. ActuatorA device that takes an electrical signal from a computer and turns it into a physical action (like movement, sound, or light). It's like the 'muscles' of a device.The motor in a smart pet feeder that turns to release food is an actuator. InputData or a signal that is sent *to* a computer system. In IoT, this data usually comes from a sensor.A motion sensor sends an 'input' signal to a security system when it detects movement. OutputData or a signal that...

The Sensor-Process-Actuator (SPA) Pattern 1. SENSE: Read a value from a sensor. 2. PROCESS: Make a decision based on that value. 3. ACT: Send a command to an actuator. This is the fundamental logic flow for almost all simple IoT systems. Always think: what am I sensing, what is my rule, and what action should happen? The 'IF-THEN' Control Structure IF (sensor_value meets a condition) THEN (perform_actuator_action) This is the most common way to program the 'process' step. We use a conditional statement to check the sensor data against a threshold and decide whether to activate the actuator.