Robotics and AI: Building Blocks of a Robotic System

The Golden Sequence in Robotics

• Robots do not move randomly; they operate through a repeating cycle known as the Golden Sequence:
  • SENSE: Gather information from the surroundings.
  • THINK: Apply specific rules based on the information gathered.
  • ACT: Create a response or physical action.
• Every robotic system, regardless of its level of complexity, follows this basic sequence to interact with its environment.

Perception: Humans vs. Robots

• Humans use biological sense organs such as eyes, ears, and skin to gather information and naturally attach meanings to observations (e.g., "the room is dark" or "the floor is cold").
• Robots experience the world through measurements rather than meanings.
• A robot does not understand concepts like "bright," "dark," "comfortable," or "dangerous."
• Instead, a robot lives in a world of numbers where changes in environmental conditions become changing sensor values.
• It does not truly "know" a room is dark; it only processes the information that a specific sensor value has changed.

The Four Major Parts of a Robotic System

Robotic systems are composed of four primary systems working in unison, often implemented using Witblox Kits:

• Power System: Provides the necessary energy for the entire system.
• Input System: Collects information from the environment.
• Control System: Processes information and makes decisions.
• Output System: Performs physical actions based on decisions.

The Power System: The Foundation of Energy

• Energy is required before a robot can sense, think, or act. Without it, electronic components cannot operate.
• In specialized robotics kits, energy is supplied by a battery and distributed via a Power Block.
• The Power Block acts as the starting point, providing energy to all connected sensors, controllers, and output devices.
• The battery serves as the storage unit, while the Power Block serves as the distribution hub.

The Input System: Sensors as Sense Organs

• Input devices are called sensors. Their role is to detect physical changes in the environment and convert those changes into electrical signals.
• Sensors gather information and send it to the next stage of the system.
• Dark Sensor:
  • Designed to detect changes in ambient light.
  • When surroundings are dark, it allows current to pass through the circuit.
  • When sufficient light hits the sensor, it prevents current flow.
  • Common applications include streetlights and automatic night lamps.
• Distance Sensor:
  • Used to detect nearby objects or obstacles.
  • It operates by emitting infrared ($\text{IR}$) light. When this light hits an object, it is reflected back.
  • The sensor analyzes the reflected light; if the reflection is strong enough (indicating a close object), the sensor activates and allows current to pass.
  • If no object is nearby, the sensor remains inactive.
• Moisture Sensor:
  • Measures the water content in soil using metal probes.
  • It utilizes the principle that water allows electricity to pass more easily than dry soil.
  • By measuring electrical properties (conductivity), it estimates if the soil is dry, damp, or wet.
  • Used in smart agriculture and automatic plant-watering systems.

Signal Types in Robotics

Information travels between robotic components in the form of signals. There are two primary types:

• Analog Signals: These can take many different values within a range (e.g., $10, 145, 327, 542, 811, 967$). The signal changes gradually as the measured quantity changes.
• Digital Signals: These exist in a limited number of states. In educational robotics, these states are usually binary: $0$ and $1$ ($\text{OFF}$ and $\text{ON}$).

The Control System: Making Decisions

• Sensors collect information but do not make decisions on what to do with it; that is the responsibility of the Control System.
• The Invert Block:
  • A logic block that reverses the behavior of a system.
  • Standard Behavior: Darkness leads to the lamp glowing.
  • Inverted Behavior: Darkness leads to the lamp NOT glowing.
  • This allow engineers to change behaviors without replacing the sensor.
• The WitPro Board:
  • Acts as the central hub and the main controller for laboratory projects.
  • It receives sensor data, processes it according to user-defined connections, and sends instructions to output devices.
• The Arduino Uno:
  • A professional-grade development board used globally for advanced robotics, automation, and engineering.
  • While less common in introductory courses, it serves as the "brain" for complex real-world projects.

The Output System: Taking Action

• Output devices convert electrical signals into physical responses.
• Lamp Block: Converts signals into visible light.
• Buzzer Block: Converts signals into audible sound.
• Motor Block: Provides continuous rotation, typically used for driving robot wheels.
• Servo Motor: Moves to specific positions with high precision, used for robotic arms and grippers.

Engineering Logic and Problem Solving

Engineers must be able to design systems to reach goals or analyze existing systems to determine their logic. Consider the following logic challenge to identify an incorrect system behavior:

• System A: Power Block $\rightarrow$ Dark Sensor $\rightarrow$ Lamp Block (Correct: Lamp glows when dark).
• System B: Power Block $\rightarrow$ Dark Sensor $\rightarrow$ Invert Block $\rightarrow$ Lamp Block (Correct: Lamp stays off when dark due to the Invert Block).
• System C: Power Block $\rightarrow$ Distance Sensor $\rightarrow$ Lamp Block (Correct: Lamp glows when an object is near).
• System D: Power Block $\rightarrow$ Distance Sensor $\rightarrow$ Invert Block $\rightarrow$ Lamp Block (Incorrect: This setup would stop a lamp from glowing when an object is near; the description "lamp glows when the surroundings become dark" is logically unconnected to a distance sensor).

The Robotic Information Chain

• The complete lifecycle of a robotic action is a chain:
  1. Environmental change occurs.
  2. A sensor detects the change and creates a signal.
  3. The Control System processes the signal and makes a decision.
  4. An output device executes the physical action.
• This chain remains the foundation for everything from simple automated lamps to complex autonomous robots.