In this lesson, you'll explore key components like sensors and actuators, learn step-by-step system design, assign team roles, discuss ethics, and create an initial plan. 

Embedded systems are specialised computers integrated into devices for specific tasks, like a smart thermostat. You'll design automated applications while being flexible with tech like Micro:bit or Arduino.

It should span several sessions, allowing you time to think deeply and collaborate with your team.

Start by understanding core components of embedded systems, referencing foundations like CPU architecture and digital vs. analogue inputs from earlier lessons. Embedded systems integrate these components to perform specific tasks efficiently.

Key components include:

• Microcontroller: The 'brain' (e.g., in Micro:bit), handling processing (recall CPU and memory from 'Hardware and OS' unit). It executes instructions and manages data flow.
• Sensors: Inputs that detect environmental changes, like temperature sensors (analogue, providing continuous values) or buttons (digital, providing on/off states).
• Actuators: Outputs that perform physical actions, like LEDs for lighting or motors for movement, responding to microcontroller commands.
• Power Supply and Connections: Batteries or adapters for energy, and wires or circuits for integrating components securely.

This demonstrates abstraction: focusing on essential parts while ignoring unnecessary details to simplify design.

Now, design your embedded system step by step. This process builds on computational thinking skills like problem-solving and algorithmic thinking, helping you break down complex tasks into manageable parts.

1. Define the Problem: Clearly state what task your system will automate. Think about real-world needs, such as monitoring room temperature or detecting motion for security. Example: Create a system that automatically waters plants when soil moisture is low.
2. Choose Components: Select appropriate sensors and actuators based on your problem. Be flexible with available technology – for instance, use a Micro:bit's built-in sensors or add external ones via GPIO pins. Consider compatibility and power requirements.
3. Sketch the System: Draw a diagram showing how components connect. Use free tools like draw.io, or simply sketch on paper and scan it. Label inputs, outputs, and the microcontroller clearly to visualise the flow.
4. Plan the Logic: Outline the system's behaviour using pseudocode. This is like a blueprint for your program, incorporating sequences, conditionals, and loops (outcome 2.6). Example: IF sensor_value > threshold THEN activate actuator.
5. Consider Inputs/Outputs: Differentiate between digital inputs/outputs (simple on/off, like a button or LED) and analogue ones (continuous values, like a temperature sensor – recall outcome 2.14). Think about how you'll read and respond to these in your code.

Example Pseudocode for a Light-Activated LED:

WHILE true
    read analogue input from light sensor
    IF input < 500 THEN
        turn on LED
    ELSE
        turn off LED
    END IF
END WHILE

Embedded systems are everywhere in our daily lives, from smart home devices to medical equipment, and they can have significant ethical and societal impacts. In this step, you'll discuss these aspects, building on what you've learned about the relationship between computing technologies and society and the positive and negative impacts on culture and society. For example, while these systems can improve efficiency and safety, they might also raise concerns about privacy or unintended harm.

Take time to think about how your embedded system could affect people and the environment. Use the following prompts to guide your discussion:

• Privacy: Consider how your system collects or stores data. For instance, if it uses sensors to monitor activity, how can you ensure user data isn't misused? A good practice is to avoid unnecessary data logging and inform users about what data is collected.
• Safety: Think about potential risks from actuators or outputs. For example, if your system controls a motor, set speed limits to prevent accidents. Ask: What could go wrong, and how can we add safeguards?
• Accessibility: Ensure your design is inclusive, following principles like universal design. Could adaptive technology help people with disabilities use your system? For example, add audio feedback for visually impaired users.
• Environmental Impact: Evaluate the system's power consumption or material use. Opt for energy-efficient components to reduce waste, and consider the long-term effects on resources.