Automated and emerging technologies
Cambridge IGCSE Computer Science 0478 · Paper 1 · Topic 6
Worth about 7 of the 75 marks on a typical Paper 1, usually as a scenario: a farm, a factory, a greenhouse or a self-driving car.
1. Automated systems
An automated system uses sensors, a microprocessor and actuators working together to control a process without human input.
- Sensors measure a physical property, such as temperature, and send the data to the microprocessor. An analogue-to-digital converter (ADC) converts the readings to digital.
- The microprocessor compares each reading with stored values.
- If action is needed, the microprocessor sends a signal to an actuator, such as a motor, heater or valve.
- The process repeats continuously.
2. Example: an automated greenhouse
Try it: an automated greenhouse
Move the sliders to change the conditions. The microprocessor compares each sensor reading with its stored range and switches the actuators.
3. Advantages and disadvantages
In an exam, apply these to the scenario you are given: industry, transport, agriculture, weather, gaming, lighting or science.
| Advantages | Disadvantages |
|---|---|
| Faster, and works 24 hours a day without breaks | Expensive to set up and maintain |
| More accurate and consistent than a human | A fault or sensor failure can cause serious problems |
| Safer: can work in dangerous places | Can be hacked or affected by malware |
| Can reduce costs over time, e.g. fewer staff | Can cause job losses |
| Reacts instantly to changes | Cannot deal well with situations it was not programmed for |
Example in context: automatic street lighting saves energy because a light sensor turns lights on only when it is dark, but a faulty sensor could leave a street dark at night.
4. Robotics
Robotics is the branch of computer science that covers the design, construction and operation of robots. Examples include factory equipment, domestic robots (robot vacuum cleaners) and drones.
A robot has three characteristics:
- a mechanical structure or framework
- electrical components, such as sensors, microprocessors and actuators
- it is programmable
5. Roles of robots
| Area | Example use |
|---|---|
| Industry | Welding and painting cars on a production line |
| Transport | Self-driving cars, automatic trains |
| Agriculture | Harvesting fruit, drones spraying crops |
| Medicine | Assisting surgeons with precise operations |
| Domestic | Robot vacuum cleaners and lawn mowers |
| Entertainment | Animatronics in theme parks, camera robots in films |
| Advantages | Disadvantages |
|---|---|
| Work continuously without tiring | High purchase and maintenance cost |
| Precise and consistent | Replace human jobs |
| Can work in dangerous environments | Limited to the tasks they are programmed for |
| Can be cheaper in the long run | Need skilled staff to program and repair |
6. Artificial intelligence
Artificial intelligence (AI) is the branch of computer science dealing with the simulation of intelligent behaviour by computers. Its main characteristics are:
- the collection of data and the rules for using that data
- the ability to reason
- it can include the ability to learn and adapt
7. Expert systems
An expert system copies the knowledge of a human expert, for example in medical diagnosis or finding faults in a car.
| Component | Role |
|---|---|
| Knowledge base | A database of facts about the subject |
| Rule base | IF…THEN rules for using the facts |
| Inference engine | Applies the rules to the facts and the user’s answers to reach a conclusion |
| Interface | Asks the user questions and shows the result, often with a probability or explanation |
The user answers questions through the interface; the inference engine searches the knowledge base using the rule base, and the interface shows the diagnosis.
8. Machine learning
Machine learning is when a program can automatically adapt its own processes and/or data. It is trained on large amounts of data, finds patterns, and improves its results with experience, without being reprogrammed. Examples: spam filters that learn which emails are spam, recommendation systems, and face recognition.
9. Examiner tips
- Use the scenario. Name the sensor and actuator that fit (e.g. a moisture sensor and a water pump for a farm), not general ones.
- Describe the full loop: sensor → ADC → microprocessor compares with stored values → actuator → repeat.
- The microprocessor makes the decision, not the sensor.
- Robot characteristics: mechanical structure, electrical components, programmable. Give all three.
- Expert system components: knowledge base, rule base, inference engine, interface.
- Machine learning adapts itself; an expert system follows its fixed rules.
- Be specific with disadvantages: “expensive to set up” beats “it costs money”.
10. Practice questions
Practice: answer and check instantly
Type a short answer, then press Check or Enter.
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The microprocessor.
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An actuator.
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An analogue-to-digital converter (ADC).
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The inference engine.
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The knowledge base.
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Programmable.
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Machine learning.
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A moisture sensor.
Exam-style questions
9. A farm uses an automated system to water its crops. Describe how the system works. [5]
Show mark guide
Any five: a moisture sensor measures the moisture of the soil · the reading is converted to digital by an ADC · it is sent to the microprocessor · the microprocessor compares it with a stored value · if it is below the value, a signal is sent to an actuator to turn on the water pump/sprinkler · if it is high enough, the pump is turned off · the process repeats continuously.
10. Describe two advantages and one disadvantage of using robots on a car production line. [3]
Show mark guide
Advantages, e.g. robots can work 24/7 without breaks, so more cars are made [1]; robots are precise, so every car is built to the same standard [1]. Disadvantage, e.g. expensive to buy and maintain / workers may lose their jobs [1].
11. Topic test: predict your grade
Topic test: predict your grade
15 questions, about 10 minutes. Answer them all, then press Mark my test.
Frequently asked questions
What is an automated system?
An automated system uses sensors, a microprocessor and actuators to carry out a task with little or no human input, for example a smart thermostat or a production line robot.
What are the characteristics of a robot?
A robot has a mechanical structure, electrical components such as sensors and actuators, and is programmable so it can carry out tasks.
What is the difference between AI and machine learning?
Artificial intelligence is the wider idea of computers performing tasks that normally need human intelligence. Machine learning is a type of AI where the system improves by learning from data instead of following fixed rules.