[vc_row][vc_column][vc_single_image source=”featured_image” img_size=”full” alignment=”center”][vc_column_text]Up until now, you’ve likely heard the term “IoT device” thrown around, especially in conversations about cutting-edge technology. But what exactly makes up an Internet of Things (IoT) device? While some may consider this a basic question, the goal of this blog is to provide a thorough understanding for everyone, whether you’re a novice or a seasoned expert.
Most of us are familiar with IoT devices in our daily lives: think smart bulbs controlled via smartphone apps or thermostats adjusted remotely. But it’s not just in consumer goods where IoT shines; the technology has found a crucial place within industries as well. IoT devices are frequently used to remotely monitor production equipment, eliminating the need for constant visual inspections—a leap forward in industrial automation.
In the healthcare sector, the impact has been profound. Remote monitoring of patients has significantly lightened the workload for medical staff. Doctors can now better manage and monitor their patients using smartphones or computers, thus elevating the standard of healthcare to new heights.
With this broad impact across various sectors, understanding the essential components of an IoT device becomes crucial. Whether it’s for industrial control, home alarm systems, or medical equipment monitoring, the basic components remain consistent. In this blog, we’ll delve deep into what makes up an IoT device and guide you through each critical element to consider.
Connectivity: The Backbone of IoT Devices
In the realm of Internet of Things (IoT) devices, connectivity serves as a critical backbone. The choice of connectivity depends significantly on where the data is destined for and what bandwidth requirements are needed. These factors, in turn, vary depending on the type of sensor and data transmission frequency.
There are several connectivity technologies employed in IoT devices. Some devices leverage mesh networks for communication, while others opt for cellular or even satellite connectivity. The choice of technology hinges on sensor characteristics and the distance over which information needs to be transmitted.
In specific scenarios, long-distance communications with low bandwidth are required. One prominent example of this is LoRa technology, which is designed for low-power wide-area networks (LPWANs). Conversely, in other situations, a hybrid solution combining technologies may be the optimal choice. A case in point is Amazon Sidewalk, which blends technologies like LoRa and Bluetooth Low Energy (BLE) to create a more versatile and efficient network.
The connectivity options available can be overwhelming. However, they allow for tailored solutions that fit specific use cases—whether that’s industrial automation, healthcare monitoring, or smart home systems. In this blog, we explore these different connectivity technologies in-depth, to help you understand which is the best fit for your IoT application.
Sensors: Tailoring to Environmental Contexts
Sensors are another critical component of IoT systems, and their selection should be based on the type of environment they will be monitoring. The environment has a significant impact on both the sensor’s performance and its cost. For instance, using a temperature sensor to monitor a controlled lab environment is vastly different from using one in a salty or corrosive atmosphere. Exposure to extreme environmental conditions may require sensors specifically designed to withstand and provide accurate measurements under those particular circumstances.
Therefore, the choice of sensor should not only consider the type of data that needs to be collected but also the environmental conditions in which it will operate. Whether you are dealing with industrial settings, healthcare environments, or smart home systems, selecting the appropriate sensor can make a substantial difference in the system’s effectiveness and reliability.
This tailored approach to sensor selection ensures that your IoT system is not only efficient but also resilient, capable of performing optimally even in less-than-ideal conditions.
Power Supply: A Critical Factor Influencing Communication Choices
The power supply is a critical aspect that significantly influences the choice of communication technology in an IoT system. It’s one thing to have a stable and constant electrical source, but it’s entirely different when sensors are located in remote areas where access to a continuous power supply might be challenging or costly.
One solution to this challenge is the utilization of ambient energy sources, allowing the creation of autonomous and sustainable systems. This eliminates the need to rely on batteries or external electrical connections. Known as “energy harvesting,” this approach is particularly beneficial in various applications such as environmental monitoring, precision agriculture, and sensor network management.
By employing energy harvesting techniques, you can make your IoT system more robust and adaptable, capable of functioning optimally even in environments where a traditional power supply is impractical or too costly. This not only improves the efficiency of the system but also enhances its sustainability, making it a more environmentally friendly option.
User Interface: A Key Aspect of User Interaction in the IoT Device
The user interface refers to how users will visualize or input information into the IoT device. This can be achieved through LEDs or a display screen. Important factors to consider include the use of color screens or, in situations where reduced energy consumption is a requirement, the option to use electronic ink (ePaper) technology.
The user interface serves as the gateway between the user and the device, making it essential to design it in a way that enhances usability and enriches user experience. Whether it’s a simple LED indicator that shows system status or a full-color touch screen that provides in-depth control and monitoring, the choice of user interface can significantly impact how effectively users can interact with the IoT system.
For instance, color screens may offer a richer, more interactive experience but generally consume more power. In contrast, ePaper displays are more energy-efficient and are read easily in bright sunlight, making them ideal for outdoor applications or settings where power conservation is crucial.
Therefore, the selection of the appropriate user interface should take into account not just the requirements for data visualization but also considerations like power efficiency and environmental conditions where the device will operate.
Microcontroller: The Brain of the IoT Device
When it comes to selecting a microcontroller for your IoT device, there are several key aspects related to computational processing that you must consider. First, evaluate the type of application you plan to use and determine the specific requirements for flash memory (FASH) and RAM. Additionally, it’s important to decide whether you need the integration of a specific transceiver, depending on the connectivity needs of your project. Security requirements for the application should also be closely scrutinized.
The costs associated with the microcontroller are a critical factor to consider. The price can vary based on the required interface, whether it’s SPI, I2C, or others. Moreover, it’s essential to examine the framework available for the microcontroller, as this will influence the number of libraries you’ll need to implement and the time required for project development.
Choosing the right microcontroller and framework is crucial for ensuring optimal performance and efficient development. This component serves as the “brain” of the IoT system, responsible for processing data from sensors, managing connectivity, and executing commands. Therefore, the selection should be made with a thorough understanding of your device’s needs in terms of processing power, memory, connectivity options, and security. By doing so, you can establish a robust foundation for your IoT project, balancing performance, development speed, and cost.
How Do We Start? A Practical Example
We have previously discussed the steps to follow in our IoT project. This time, we face the challenge of creating a highly energy-efficient IoT device capable of connecting via Bluetooth Low Energy (BLE). The main task involves sending temperature and humidity sensor data through separate services while requiring a lithium battery.
To tackle this complex task, we first need to break it down into its essential components and select an appropriate development kit that includes:
A BLE (Bluetooth Low Energy) module.
A temperature and humidity sensor.
Battery-powered with energy-saving features.
We will begin by exploring options for implementing low-power BLE and then evaluate a promising development kit provided by Silicon Labs through their unified development environment called “Simplicity Studio.”
Before diving into the details, let’s review the key features of this kit and how they align with our specific requirements.
Development Kit Features
Integrated peripheral power control for ultra-low-power operation.
Relative humidity and temperature sensor.
Ambient light sensor.
Hall effect sensor.
6-axis inertial sensor.
Stereo PDM microphones.
8 Mbit serial flash.
User LED and power button.
20-pin breakout pins with 2.54 mm pitch.
Onboard SEGGER J-Link debugger.
Virtual COM port.
Mini Simplicity connector for AEM and virtual COM port using an external Silicon Labs debugger.
Power supply through USB or cell-type battery.
This kit seems ideal for meeting our requirements. It enables us to measure temperature and humidity, and all the necessary libraries are readily available in their development environment.
Development Kit Review
A significant advantage of this kit is that it includes debugging tools for the device. The ambient sensor is useful for other applications, and the accelerometer will be beneficial for other IoT devices we plan to develop. Also, it is low cost. Personally, I appreciate its compact size, ideal for prototyping and showcasing to our clients.
The kit’s power aspect serves us well as it has a battery management option, as illustrated in the following diagram.
An example of blocks of the kit
We chose to use the Si7021 sensor due to its energy efficiency, and the necessary libraries are already available and ready for use. What remains now are the essential services and features for BLE connectivity, and here comes the good news. The manufacturer provides comprehensive documentation that will allow us to develop the application efficiently.
As you can see in the image, incorporating this service is a simple and straightforward process.
Battery Durability Assessment
To evaluate battery durability, we cannot solely rely on a standard multimeter. Instead, we require a specialized tool from Nordic, the Power Profiler Kit II (PPK2).
The Power Profiler Kit II (PPK2) is a versatile and affordable tool designed to accurately measure the real-time energy consumption of your electronic designs. It can supply power to an external board or function as an ammeter, measuring currents ranging from a minimum of 500 nA (nanoamperes) to a maximum of 1 A (ampere), offering a detailed and comprehensive view of your application’s specific current profile.
As seen in the images, it is possible to visualize the energy consumption in different ranges, facilitating precise calculations to optimally estimate battery life.
In this blog, we’ve undertaken a comprehensive exploration of the critical elements that make up an Internet of Things (IoT) device. From connectivity options to sensor selection, power supply considerations, and user interface design, we’ve dissected each component to give you a well-rounded understanding of what goes into an IoT project.
Additionally, we’ve walked through a practical example featuring a development kit that satisfies the criteria for a high-performing, energy-efficient IoT device. Armed with this knowledge and the right set of tools, you’re well-equipped to venture into the ever-expanding universe of IoT, whether your interest lies in smart homes, healthcare, or industrial automation. The possibilities are endless, and the future is promising.[/vc_column_text][/vc_column][/vc_row]
