Examples of embedded systems

What are Examples of Embedded Systems?

Examples of embedded systems are widespread and found in numerous devices we utilise daily. They help to make devices more intelligent and responsive, enhancing their functionality and performance. For each example, certain unique characteristics customised to the specific application can be observed.

Everyday Examples of Embedded Systems

From your morning alarms to your evening television shows, a host of everyday appliances work on the principles of embedded systems. Take a look at a few.

• Smartphones are one of the most prevalent examples. They contain a multitude of embedded systems designed to manage everything from touch response to connection to the cell network.
• Digital Watches or Fitness Trackers: They are integrated with embedded systems to perform functions like counting steps, monitoring heart rates, and so forth.
• Home automation devices like smart thermostats, security systems, or smart refrigerators also contain embedded systems to perform their specialised functions.
• Televisions, music players, and other entertainment devices all have embedded systems that decode compressed data streams and provide the user interface.

Industrial Examples of Embedded Systems

Industrially, embedded systems play a significant role in automating complex processes and improving efficiency. Observing the following examples will provide you with a clearer understanding of their vital role in various industries.

• Manufacturing Systems: Assembly lines, robotic devices, and control systems used in factories are powered by embedded systems.
• Medical Equipment: Devices such as ECG, MRI, and dialysis machines contain embedded systems which perform various sophisticated functions.
• Aerospace Applications: The flight control systems and navigation systems in aeroplanes, spacecraft, and satellites all involve complex embedded systems.
• Automotive Applications: Modern vehicles contain dozens of embedded systems controlling everything from the engine and brakes to the climate control and entertainment systems.

Digging Deeper into Embedded Systems

The world of embedded systems is vast, entailing a myriad of applications in various domains.

Types of Embedded Systems with Examples

Embedded systems can be categorised into different types based on functionality, performance, and other attributes. The primary ones are stand-alone, real-time, networked, or mobile.

Stand-alone Embedded Systems

Stand-alone embedded systems, as the name suggests, operate independently without requiring a host system or network support. These systems take inputs, process the data, and then produce the desired output. They find relevance in a wide range of applications and devices.

• Calculators: Probably the simplest example of a stand-alone embedded system. They take numeric inputs, perform calculations and display the result on a screen.
• Thermostats: These devices take temperature readings, compare them to a set value, and control a heating or cooling system to maintain the desired temperature.
• MP3 players: These devices read audio files from a storage device, decode the compressed data, and play the resulting audio through a speaker or headphone jack.

Real-time Embedded Systems

Real-time embedded systems are designed to perform tasks within a specified timeframe or 'deadline'. Any delay in processing can lead to undesired results or even system failure. These systems are further divided into two types: Hard real-time and Soft real-time systems.

Networked Embedded Systems

Networked embedded systems, as their name suggests, are connected to a network, typically a Local Area Network (LAN). They rely on the network to receive inputs and sometimes to send outputs. The network protocol stack handles all network tasks, making the programming of these devices similar to stand-alone embedded systems.

• Smart Home Devices: Devices like smart lights, smart locks, or smart thermostats are connected to your home network, allowing you to control them remotely.
• Industrial Control Systems: Factory automation systems often use networked embedded systems to take readings from various sensors around the plant, and then control various actuators based on that data.

Mobile Embedded Systems

Mobile embedded systems are designed for portable and handheld devices. The characteristics of these systems include low power consumption, small size, and ruggedness for reliable operation.

• Smartphones and Tablets: These devices include numerous embedded systems to manage their interfaces and communication systems. They are designed to be compact and energy-efficient.
• Wearable Fitness Trackers: These keep track of various health parameters and provide alerts at specified intervals. They must be small and take minimal power to allow for continuous usage.

The Evolution of Embedded Systems

Embedded systems have come a long way since their inception. The evolution spans from basic independent systems to highly complex, multitasking machines underpinning the Internet of Things (IoT). The history of such systems is marked with significant milestones and transformative shifts.

Historical Examples of Embedded Systems

By delving into the past, you will find some early yet impressive examples of embedded systems. Each one served as a step towards the sophisticated systems that you encounter today. To understand their evolution, it's useful to consider a brief history of embedded systems.

The Dawn of Embedded Systems

The roots of embedded systems date back to the mid-20th century. Arguably, the first recognisable embedded system was the Apollo Guidance Computer (AGC) developed by NASA for the Apollo missions to the moon in the 1960s.

The AGC was a real-time, multitasking computer that fit in a small box (roughly a cubic foot) and weighed just over 30 kilograms. It was tasked with handling all the navigation computations and controlling the spacecraft. Precise real-time computations were essential for the successful landing of the lunar module on the moon's surface.

The AGC was designed using thousands of logic gates implemented with integrated circuits, marking it as one of the earliest large-scale integrated (LSI) designs. This approach revolutionised computer engineering and paved the way for personal computers and modern embedded systems.

Embedded Systems in the Digital Age

The microprocessor boom of the late 20th century impacted embedded systems significantly. As processing power became more available and affordable, new horizons for embedded systems started emerging, and they began to transition into the digital age.

The first microprocessor-controlled embedded system was the Autonetics D-17B, a component of the Minuteman II intercontinental ballistic missile that was developed in the mid-1960s. It used over 3000 integrated circuits, and it had no operating system – the software was directly executed on the hardware.

The next huge leap in the realm of embedded systems was the advent of the Intel 4004 microprocessor in 1971. The Intel 4004 was a 4-bit microprocessor designed for a calculator but ended up revolutionising the way digital circuits were designed by integrating the processor, memory, and input/output controls onto a single chip.

Today, thanks to advances in hardware technologies and software methodologies, embedded systems are everywhere, from smart home devices and portable gadgets to industrial automation systems and aerospace applications, nudging the world closer to realising the Internet of Things.

Exploring Real-Time Embedded Systems

Real-time embedded systems play a crucial role in our day-to-day lives. These systems are distinguished by their ability to respond to events or inputs within a strict timeframe, making them vital in applications where timeliness is a critical factor.

Example of Real-Time Embedded System

Looking at the broader landscape of real-time embedded systems, you'll find them in industries ranging from transportation to healthcare, and beyond. The shared characteristic among all these systems is their need to provide responses in a timely manner as part of their operation.

To comprehend the concept better, consider a modern car's anti-lock braking system (ABS). This is a perfect example of a hard real-time embedded system. ABS monitors the rotational speed of each wheel during braking. When it detects that one or more wheels are about to lock up, it automatically modulates the brake pressure to that wheel or wheels.

if wheelSpeed < threshold
    reduceBrakePressure(wheel)
else 
    maintainBrakePressure(wheel)

This code, although simplistic, demonstrates the basis of an ABS function. Still, in practice, the system involves more complex features such as vehicle dynamics controls and traction control systems.

Real-Time Embedded Systems in Transportation

Transportation systems involve various real-time components aimed at enhancing safety, efficiency, and convenience.

• Aircraft Systems: The avionics of an airplane incorporates multiple real-time systems. These include the flight control system, which must respond immediately to pilot input or automatic control signals to ensure the plane's stable flight.
• Traffic Light Controllers: These systems must switch lights at predefined intervals, but may also need to respond to emergency vehicles or malfunction detection in real-time.
• Navigation Systems: Devices like GPS receivers are fed real-time data about satellite positions and must compute and display the device's location in real-time.

Real-time embedded systems in transportation often fall under the "hard real-time" category, where a delay in the system's response could lead to catastrophic results, such as accidents in the case of transportation systems.

Real-Time Embedded Systems in Healthcare

In the healthcare industry, there are several real-time embedded systems that are used to automate complex medical procedures and monitor patient's health.

• Medical Imaging Systems: Devices such as CT scanners, MRI machines, and ultrasound devices use real-time systems to process and display images quickly during scans.
• Patient Monitoring Systems: These systems continuously monitor vital parameters like heart rate, blood pressure, oxygen level and provide real-time data to medical professionals.
• Assistive Devices: Devices like hearing aids and pacemakers are also embedded systems that operate in real-time, continually adjusting their operation according to the patient's needs.

Hospitals also employ real-time location systems (RTLS) to track medical equipment, staff, and patients in real-time. For instance, the expected position of a mobile medical device can be computed by a real-time embedded system using a formula derived from the laws of physics, such as

where \(x\) is the current position, \(x_0\) is the initial position, \(v_0\) is the initial velocity, \(a\) is the acceleration, and \(t\) is the time elapsed. This helps enhance resource management and patient care.

The Versatility of Embedded Systems

Embedded systems, undoubtedly, hold a significant place in technology owing to their versatility and broad application base. Ranging from home appliances and consumer electronics to industrial equipment, medical devices and automotive systems, examples of embedded systems are all around you.

Comparing Various Examples of Embedded Systems

When considering examples of embedded systems, it's important to understand that they can be vastly different from one another depending on their functionality, complexity, and design philosophies. Some are designed to perform a single function, while others can handle a multitude of tasks. Some are standalone units, while others are part of a larger network. Let's further examine some embedded system examples and discern how they vary.

Benefits and Limitations of Different Embedded Systems

Specific embedded systems can offer unique advantages based on the complexity and functionality they possess. Before delving into that, it's worth noting that all embedded systems share some common benefits, including efficiency, reliability, and performance. By design, embedded systems are optimised for their specific tasks, leading to efficient use of resources, reliable operation, and optimal performance.

Yet, the diversity in the embedded systems landscape implies that not every system will be suited for every purpose. Depending on the design and purpose, these systems also come with limitations. Variance can exist in aspects like computational capacity, flexibility, upgradability, interoperability, and cost. And while these might not be considered outright flaws, they could limit a system's applicability in certain situations.

How to Choose the Right Embedded System for Your Needs

Understanding the diversity of embedded systems, their benefits, limitations, and the environments in need of such systems is a necessary precursor to selecting the right embedded system. The "rightness" is derived from a match between the system's capabilities and the use-case requirements. Follow these guidelines:

• Identify the core functionalities that the embedded system must provide.
• Decide on real-time requirements. Does the system need to respond immediately to an event, or is there some flexibility here?
• Think about energy efficiency. Is the system battery-powered? Is power usage a major concern?
• Consider the interoperability requirements. Does the system need to connect with other systems or networks?
• Estimate a reasonable cost for the system while maintaining the right balance with other design parameters.

In every case, these factors must guide the choice you make, ensuring that the system specification aligns with your needs. By carefully characterising your problem domain and doing due diligence while considering the available options, you can ensure that the chosen embedded system turns out to be a tech-ally.