Obstacle-Avoidance Robot Design and Automation for SS 1

Class: SSS 1
Term: Second Term
Week: 3
Age: 15 years
Duration: 60 minutes
Subject: Digital Technologies
Curriculum Theme: Emerging Technologies
Focal competence: Building an obstacle avoidance robot
Key competencies/values: Critical Thinking; Research and Problem Solving; Problem Solving
Skills:

• Building a two-wheel differential drive system
• components (microcontroller: microbit v2, ESP32, Raspberry Pi Pico, motor driver: TB6612FNG/L298 N, chassis, wheels, castor, power supply, Ultrasonic/bump sensor, LED/buzzer, adhesives.)

Previous Lesson: Computational Thinking Tools, Python, Spreadsheets and Problem-Solving Steps
Topic: Robot Design I (Obstacle-Avoidance Robot)
Subject Matter: Meaning of Robot Design I (ObstacleAvoidance Robot), Meaning of robot design and automation

Specific Objectives

By the end of the lesson, pupils/students should be able to:

Cognitive Domain

• Define robot design and automation.
• Define Robot Design I (Obstacle-Avoidance Robot).
• Explain robot design and automation.
• Describe the steps in building a robot.
• Describe the relationship between robots and automation.

Affective Domain

• Appreciate the importance of critical thinking in solving design challenges.
• Value problem-solving approaches in robotics.

Psychomotor Domain

• Identify various components used in building a two-wheel differential drive system mobile robot.
• Demonstrate basic assembly of robot components (if resources permit).

Social Domain

• Collaborate effectively in discussing robot design concepts.

Reference Materials

The following resources were used in planning this lesson:

• 2025 New Revised Senior Secondary Education Curriculum (SSEC)
• Relevant State Unified Scheme of Work
• Digital Technologies for Senior Secondary Schools, Book 1
• The HeadTeacher Scheme of work For The New Revised Senior Secondary Education Curriculum (SSEC)

Instructional Materials

The teacher will teach this lesson with the aid of:

• Robotics development starter kits (e.g., Arduino, Raspberry Pi, Micro:bit)
• Digital multimeter
• Datasheets/Pinout sheets for microcontrollers and motor drivers
• Wiring diagrams
• Internet access for video demonstrations
• Computer system
• Projector (optional)
• Whiteboard and markers
• Sample robot components (microcontroller, motor driver, chassis, wheels, castor, power supply, ultrasonic sensor, LED, buzzer, adhesives)

Rationale for the Lesson

This lesson provides students with foundational knowledge in robot design and automation, which are key aspects of emerging digital technologies. Understanding these concepts helps students develop critical thinking and problem-solving skills essential for innovation in a technologically advancing world. It also lays the groundwork for practical applications in engineering and computer science.

Prerequisite/Previous Knowledge

Students should have a basic understanding of digital devices, simple circuits, and the concept of input and output.

Lesson Content/Board Summary

Robot Design I (Obstacle-Avoidance Robot)

Meaning of Robot Design

Robot design is the process of planning, creating, and developing robots. It involves combining mechanical, electrical, and computer science principles to build machines that can perform tasks autonomously or semi-autonomously. This process includes conceptualisation, material selection, component integration, and programming.

Meaning of Automation

Automation refers to the use of technology to perform tasks with minimal human intervention. It involves designing and implementing systems that can operate automatically, often using robots, control systems, and other advanced technologies to increase efficiency, productivity, and safety in various processes.

Relationship Between Robot Design and Automation

Robot design is a fundamental aspect of automation. Robots are often designed specifically to automate tasks that are repetitive, dangerous, or require high precision. Automation relies on well-designed robots to execute programmed actions, gather data, and interact with their environment to achieve specific objectives without constant human oversight.

Meaning of Obstacle-Avoidance Robot

An obstacle-avoidance robot is a type of autonomous robot designed to detect and navigate around obstacles in its path without colliding with them. These robots typically use sensors (like ultrasonic or infrared sensors) to perceive their surroundings and a control system to process this information, allowing them to change direction or stop when an obstacle is detected.

Components for Building a Two-Wheel Differential Drive System Mobile Robot

A two-wheel differential drive system is a common setup for mobile robots, allowing movement and steering by controlling the speed and direction of two independent drive wheels. Key components include:

1. Microcontroller: The “brain” of the robot that processes sensor data and controls motors. Examples include:
   • Micro:bit v2: A small, programmable computer board suitable for beginners.
   • ESP32: A powerful microcontroller with Wi-Fi and Bluetooth capabilities.
   • Raspberry Pi Pico: A low-cost, high-performance microcontroller board.
2. Motor Driver (e.g., TB6612FNG/L298N): An electronic circuit that allows the microcontroller to control the speed and direction of DC motors, as microcontrollers cannot directly supply enough current for motors.
3. Chassis: The structural frame of the robot, providing a base for mounting all other components.
4. Wheels: Typically two drive wheels attached to motors and a third passive castor wheel for balance and smooth movement.
5. Castor: A small, freely rotating wheel (often at the front or back) that provides stability and allows the robot to turn easily.
6. Power Supply: Batteries (e.g., AA, LiPo) or a power bank that provides electrical energy to all components.
7. Ultrasonic/Bump Sensor:
   • Ultrasonic Sensor: Uses sound waves to measure the distance to objects, enabling obstacle detection.
   • Bump Sensor: A switch that detects physical contact with an obstacle.
8. LED/Buzzer: Output devices used for visual (LED) or auditory (buzzer) feedback, indicating robot status or obstacle detection.
9. Adhesives: Materials like glue, tape, or cable ties used for securing components to the chassis.

Steps in Building a Robot

Building a robot generally follows a systematic process:

1. Conceptualisation and Design: Define the robot’s purpose, functions, and overall structure. This involves sketching designs and planning the mechanical and electronic systems.
2. Component Selection: Choose appropriate microcontrollers, sensors, motors, motor drivers, power sources, and structural materials based on the robot’s design requirements.
3. Mechanical Assembly: Construct the robot’s physical structure (chassis), mount the motors, wheels, sensors, and other hardware components.
4. Electrical Wiring: Connect all electronic components (microcontroller, motor driver, sensors, power supply) according to a wiring diagram, ensuring correct polarity and connections.
5. Programming: Write code (e.g., in Python, C++) for the microcontroller to control the robot’s behaviour, process sensor inputs, and actuate motors.
6. Testing and Debugging: Thoroughly test the robot’s functionality, identify and fix any mechanical, electrical, or programming issues. This often involves iterative adjustments.
7. Refinement and Calibration: Fine-tune the robot’s performance, calibrate sensors, and optimise movement parameters for desired operation.

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Observation, Practical Activity

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Engagement/Questioning

Teacher’s Activity: The teacher greets the students and asks them what they understand by the term “robot” and if they have seen any robots in movies or real life. The teacher then introduces the topic: Robot Design I (Obstacle-Avoidance Robot).

Pupils’ Activity: Pupils respond to the questions and listen attentively to the introduction.

Learning Point: Introduction to robots

Step 2: Meaning of Robot Design and Automation

Time: 10 minutes

Teaching Skill: Explanation/Brainstorming

Teacher’s Activity: The teacher guides students to brainstorm on the meaning of robot design and automation, providing clear definitions and examples. The teacher explains how robot design involves planning and building machines, while automation is about making tasks automatic.

Pupils’ Activity: Pupils participate in brainstorming, offer their ideas, and listen to the teacher’s explanations.

Learning Point: Robot design and automation definitions

Step 3: Relationship Between Robot Design and Automation

Time: 8 minutes

Teaching Skill: Explanation/Discussion

Teacher’s Activity: The teacher explains the close relationship between robot design and automation, highlighting that robots are designed to facilitate automation. The teacher uses examples to illustrate how automation relies on well-designed robots.

Pupils’ Activity: Pupils listen, ask questions, and contribute to the discussion on the relationship.

Learning Point: Robot-automation relationship

Step 4: Meaning of Obstacle-Avoidance Robot

Time: 7 minutes

Teaching Skill: Explanation/Definition

Teacher’s Activity: The teacher defines an obstacle-avoidance robot, explaining its purpose and how it uses sensors to detect and navigate around objects. The teacher may show a short video clip of an obstacle-avoidance robot in action.

Pupils’ Activity: Pupils listen to the definition and observe any video demonstrations.

Learning Point: Obstacle-avoidance robot meaning

Step 5: Components for a Two-Wheel Differential Drive System

Time: 10 minutes

Teaching Skill: Demonstration/Identification

Teacher’s Activity: The teacher displays various robot components (microcontroller, motor driver, chassis, wheels, sensors, etc.) and explains the function of each, especially for a two-wheel differential drive system. The teacher guides students to watch a video on these components.

Pupils’ Activity: Pupils observe the components, identify them, and ask questions about their functions. They watch the video attentively.

Learning Point: Robot component identification

Step 6: Steps in Building a Robot

Time: 10 minutes

Teaching Skill: Explanation/Sequencing

Teacher’s Activity: The teacher describes the general steps involved in building a robot, from conceptualisation to testing and refinement. The teacher may use a simple diagram or flowchart to illustrate the process.

Pupils’ Activity: Pupils listen and take note of the sequential steps in robot construction.

Learning Point: Robot building steps

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What is robot design?
2. How would you define automation?
3. What is an obstacle-avoidance robot?
4. Mention two components needed for a two-wheel differential drive robot.
5. State two steps involved in building a robot.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Understanding robot design concepts

Step 8: Note-Taking

Time: 10 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils/students to copy the essential Board Summary notes on robot design, automation, obstacle-avoidance robots, components, and building steps into their notebooks.

Pupils’ Activity: Pupils/students copy the notes carefully into their notebooks.

Learning Point: Recording lesson information

Step 9: Conclusion

Time: 5 minutes

Teaching Skill: Summarisation

Teacher’s Activity: The teacher briefly summarises the key concepts of robot design, automation, and obstacle-avoidance robots, reinforcing their importance in modern technology. The teacher encourages students to explore more about robotics.

Pupils’ Activity: Pupils listen to the summary and prepare for the next class.

Learning Point: Lesson concept consolidation

Continuous Assessment/Further Study

Type: Homework/Project

Instruction: Answer the following questions and research further on robot applications.

1. Explain the difference between a microcontroller and a motor driver in robot design.
2. List three real-world applications of obstacle-avoidance robots.
3. Research and identify one other type of sensor used in robotics for navigation, apart from ultrasonic and bump sensors. Describe its function.
4. Draw and label a simple diagram of a two-wheel differential drive robot, showing at least five major components.

Lesson Keywords

• Robot Design – The process of planning and creating robots.
• Automation – Using technology to perform tasks with minimal human intervention.
• Obstacle-Avoidance Robot – A robot designed to detect and navigate around objects.
• Microcontroller – The “brain” of a robot, processing data and controlling actions.
• Motor Driver – An electronic circuit that controls robot motors.
• Sensor – A device that detects and responds to physical input from the environment.
• Chassis – The structural frame of a robot.

Differentiation

For students who may struggle, the teacher will provide simplified diagrams of robot components and step-by-step guidance during the component identification and assembly explanation. Advanced learners will be encouraged to research different types of sensors and their applications in various robotic systems, or to explore basic programming concepts for simple robot movements.

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