Cambridge Syllabus Notes

Automated and Emerging Technologies – Characteristics of a Robot

Learning Objective

Students will be able to describe the characteristics of a robot (Cambridge IGCSE 0478, Topic 6.2).

1. What is a Robot?

A robot is a programmable machine that can:

Sense its environment (or its own internal state),
Process that information using a control algorithm, and
Act on the environment through mechanical motion.

It combines hardware (structure, sensors, actuators, power source) with software (control programmes, feedback loops) and is driven by a microprocessor or embedded controller. A robot may operate autonomously or under human supervision.

2. Core Characteristics of a Robot

The syllabus expects ten characteristic features. The table below expands each point, adds the required software aspect, and includes safety – a frequent exam focus.

Characteristic	What it means	Typical examples / notes
Body (Physical structure)	Mechanical framework that supports all other components; may be fixed, articulated or mobile.	Aluminium chassis, articulated arm, wheeled platform.
Sensors	Devices that gather data about the external world or internal status.	Ultrasonic distance sensor, colour camera, gyroscope, temperature probe.
Actuators	Mechanisms that convert electrical or hydraulic signals into motion or force.	Servo motor, stepper motor, pneumatic cylinder, linear actuator.
Control Unit (Microprocessor / Embedded Controller)	The “brain” that receives sensor inputs, runs the control programme and sends commands to actuators.	Arduino, Raspberry Pi, industrial PLC, embedded PC.
Software (Control algorithms & feedback)	Programmed instructions that decide how the robot should react; includes feedback loops for error correction and, in advanced systems, learning algorithms.	PID control, line‑following algorithm, simple AI routine.
Programmability	Ability to be re‑programmed to perform different tasks or modify behaviour.	Re‑uploading a new sketch to an Arduino; changing a flow‑chart on a teaching robot.
Autonomy	Degree to which the robot can operate without direct human control.	Fully autonomous vacuum cleaner vs. remote‑controlled drone.
Adaptability (Feedback & Learning)	Capability to adjust actions in response to changing conditions, often via sensor feedback or simple learning.	Obstacle‑avoidance that reroutes the path; a robot that tunes motor speed based on load.
Power Source	Provides the energy needed for all components.	Li‑ion battery pack, AC mains adapter, fuel cell.
Mobility	Means of moving through the environment.	Wheels, tracks, legs, or a stationary arm on a fixed base.
Human‑Robot Interaction (HRI)	Interfaces that allow safe and effective cooperation with people.	Touch screen, voice command, emergency‑stop button, safety light curtains.
Safety Features	Built‑in measures that protect users and the robot itself.	Emergency stop, safety interlocks, overload protection, compliant (soft) end‑effectors.

3. Common Roles of Robots

Robots are classified by the sector in which they are most frequently used. The table adds a few emerging roles to show the breadth of modern applications.

Robot Class	Typical Role	Examples
Industrial	Manufacturing tasks – welding, assembly, material handling, painting.	6‑axis welding arm, pick‑and‑place robot.
Service	Assist in homes, offices or public spaces – cleaning, delivery, security.	Robotic vacuum cleaner, autonomous delivery drone.
Medical	Support diagnosis, surgery, rehabilitation and patient care.	Da Vinci surgical system, physiotherapy exoskeleton.
Exploratory	Collect data and perform tasks in hazardous or inaccessible environments.	Planetary rover, underwater autonomous vehicle.
Educational	Teach programming, engineering concepts and problem‑solving.	LEGO Mindstorms, BBC micro:bit robot kits.
Emerging – Agricultural	Planting, weeding, harvesting, monitoring crop health.	Autonomous sprayer, fruit‑picking robot.
Emerging – Disaster‑Response	Search‑and‑rescue, hazardous‑material handling, structural inspection.	Snake‑type inspection robot, aerial rescue drone.

4. Advantages and Disadvantages of Using Robots

Advantages	Disadvantages
Higher productivity and speed. Excellent precision and repeatability. Can operate in hazardous, toxic or inaccessible environments. 24‑hour operation with consistent performance. Data collection for quality control and process optimisation. Reduced human fatigue and ergonomic risk.	High initial purchase, installation and training cost. Ongoing maintenance, possible downtime for repairs. Complex programming and system integration. Safety concerns – risk of injury if safety features are ignored. Potential job displacement and related social issues. Ethical & societal implications – privacy, data security, dependence on automation.

5. Degrees of Freedom (DoF) – Enrichment

Degrees of Freedom describe the number of independent movements a robot can make. For a robot with n joints, each providing d_i independent motions:

$$\text{DoF} = \sum_{i=1}^{n} d_i$$

More DoF give greater flexibility but increase the difficulty of control and programming. This concept is useful when discussing articulated arms or humanoid robots.

6. Visual Aid – Sample Exam‑Style Diagram

Students should be able to label a block diagram of a typical robot. The diagram below follows the format often used in IGCSE exam questions.

Block diagram: Sensors → Control Unit (Microprocessor) → Actuators; Power Supply and Communication Interface shown surrounding the robot. — Block diagram to be annotated in exam:
1. Sensors (e.g., ultrasonic, camera)
2. Control Unit / Microprocessor (runs software)
3. Actuators (motors, servos)
4. Power Supply (battery or mains)
5. Communication Interface (Wi‑Fi, Bluetooth)
6. Safety/E‑Stop (highlighted in red)

7. Links to Other Syllabus Areas

Automated Systems (Topic 6.1) – Robots are a specialised form of automated system; both share sensors, actuators and control logic.
Digital Electronics (Topic 4) – Understanding microprocessors, logic gates and interfacing circuits underpins robot control.
Data Handling (Topic 3) – Sensors generate data that must be processed, stored and sometimes transmitted.
Ethics & Impact of Technology (General) – The disadvantages section connects directly to discussion questions on societal effects.

8. Quick Revision Checklist

Definition of a robot – hardware + software, programmable, senses, processes, acts.
List and explain the ten (plus safety) characteristics.
Know at least one example for each robot class (industrial, service, medical, exploratory, educational, emerging).
Be able to discuss two advantages and two disadvantages, including an ethical point.
Recall the DoF formula (optional enrichment).
Practice labeling the block diagram – sensors, controller, actuators, power, communication, safety.

Describe the characteristics of a robot