209 Processes & Systems: Fundamentals
209.1 Learning Objectives
By the end of this series, you will be able to:
- Define Process Concepts: Explain systems, processes, and input-output transformations in IoT
- Compare Control Types: Differentiate between open-loop and closed-loop control systems
- Analyze Feedback Loops: Describe how feedback mechanisms maintain system stability
- Apply PID Control: Understand proportional, integral, and derivative control components
- Design Stable Systems: Evaluate trade-offs between different control strategies for IoT
- Implement Self-Regulation: Build systems that automatically adjust to maintain desired behavior
209.2 Prerequisites
Before diving into this series, you should be familiar with:
- Sensor Fundamentals and Types: Understanding how sensors measure physical phenomena is essential for grasping how systems transform inputs into meaningful data
- Actuators: Knowledge of actuators helps understand how systems produce physical outputs in response to control signals
- IoT Reference Models: Familiarity with layered IoT architectures provides context for where processes operate within the device-to-cloud stack
209.3 Chapter Overview
209.4 Chapter 1: Core Definitions
Processes & Systems: Core Definitions
Learn the foundational concepts that underpin all IoT system design:
- System vs Process: Understand the difference between the collection of components (system) and the transformation they perform (process)
- Block Diagram Representation: Use abstraction to represent complex systems as interconnected black boxes
- IoT System Decomposition: Break down systems into hardware, software, and network subsystems
- Input-Output Transformations: Analyze how sensors provide inputs, microcontrollers process data, and actuators produce outputs
Key Concept: Every IoT device can be analyzed as a system with inputs, a process, and outputs—understanding this framework is essential for debugging and optimization.
209.5 Chapter 2: Control Types
Processes & Systems: Control Types
Explore the fundamental distinction between control strategies:
- Open-Loop Control: Systems that operate based on predetermined inputs without measuring output
- Closed-Loop Control: Systems that continuously measure output and adjust to maintain desired setpoint
- Feedback Mechanisms: How sensors, controllers, and actuators work together in feedback loops
- Real-World Applications: Smart factory temperature control, irrigation systems, HVAC automation
Key Concept: Closed-loop systems that measure output and adjust inputs automatically are the foundation of “smart” IoT—turning simple timers into intelligent devices.
209.6 Chapter 3: PID Control
Processes & Systems: PID Control
Master the most widely used feedback control algorithm:
- The PID Formula: Proportional, Integral, and Derivative control actions
- Tuning Controllers: Finding optimal gain values for system performance
- Real IoT Examples: Smart thermostats, drone stability, water tank level control
- Control Strategy Selection: When to use PID vs simpler on/off control
Key Concept: PID combines three actions—react to current error (P), eliminate persistent offset (I), and dampen oscillations (D)—to achieve precise, stable control.
209.7 Quick Reference: Control System Comparison
| Control Type | Feedback | Accuracy | Complexity | IoT Example |
|---|---|---|---|---|
| Open-Loop | None | Low | Simple | Timer-based irrigation |
| Closed-Loop (On/Off) | Yes | Medium | Moderate | Simple thermostat |
| Closed-Loop (PID) | Yes | High | Higher | Smart HVAC, drones |
209.8 What’s Next
Start with Core Definitions to build your foundation, then progress through Control Types and PID Control for complete understanding.
For hands-on practice, continue to Process Control and PID for advanced implementations and Processes Labs and Review for practical exercises.