The Sensing Layer - IoT Foundations Module 2

Vocabulary flashcards covering the core concepts, components, and classifications of the IoT Sensing Layer, sensors, actuators, and microcontrollers.

Sensing Layer

The bottom-most layer of the $4\text{-Stage}$ IoT model responsible for data gathering via physical objects, sensors, and actuators.

Network Layer

The stage of IoT architecture focused on data transmission through the internet and network gateways.

Data Processing Layer

The layer where processing units and data analytics reside, described as where the 'thinking' happens in an IoT system.

Application Layer

The final stage of IoT architecture consisting of smart applications and management systems.

Biological Analogy (Sensing Layer)

In a human body comparison, this layer represents the senses (Skin, Eyes) and muscles (Arms).

Identification

The process of recognizing specific physical objects to provide context to gathered data, distinguished from sensing which measures values.

RFID (Radio Frequency Identification)

A technology using electromagnetic fields to automatically identify and track tags attached to objects.

Barcodes & QR Codes

Optical machine-readable labels that allow a camera sensor to identify a specific item.

Sensors

Specialized electronic devices that collect, detect, and measure physical environment parameters and convert them into outputs humans and machines can understand.

Active Sensors

Also known as parametric sensors, these require an external power source to operate and generally consume more power because they must emit energy.

Passive Sensors

Also called self-generated sensors, these generate their own electric signal and do not require an external power source.

Transduction

The vital process of converting physical energy into electrical voltage so microcontrollers can understand physical events.

Temperature Sensors

Devices where heat causes internal conductivity changes; they provide a specific millivolt change for every $1\text{-degree}$ Celsius change.

Soil Moisture Sensors

Sensors that measure the electrical dielectric of the earth to determine water content for applications like smart agriculture.

Gas and Air Quality Sensors

Sensors containing a heating element and sensing material that reacts with gas molecules like $CO$ or Methane to trigger alerts.

Acoustic Sensors

Microphones that detect sound waves and convert them into electrical oscillations to identify events like glass breaking or engine failure.

Actuators

Machine components that turn electrical commands from a controller back into physical energy, such as motion, sound, or heat.

Microcontroller (MCU)

A 'computer on a chip' containing a CPU, memory, and I/O ports designed to govern specific operations in an embedded system.

ESP32 / ESP8266

An affordable MCU family with integrated Wi-Fi and Bluetooth, best used for home automation and DIY projects.

ARM Cortex-M

A high-efficiency, industry-standard MCU architecture used in industrial sensors and medical wearables.

Arduino (Atmel/AVR)

An MCU family noted for being easy to program with massive community support, primarily used for prototyping and education.

STM32

A high-performance MCU with vast peripheral options designed for complex industrial control systems.

Sleep Modes

A design strategy used to save energy in IoT devices when no data is being gathered to extend battery life.