IB Computer Science HL · Year 2 · Lesson 35
Control systems
Operating systems coordinate resources and processes; control systems sense, decide and act in the physical world.
Paper 150 minutesA1.3.6 · A1.3.7
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Today’s targets
What you need to be able to do
2 / 7
- DescribeThe use of the control system components
- ExplainThe use of control systems in a range of real-world applications
A1.3.6A1.3.7
Paper 1 lensMatch the depth of every response to the command term. Previously learned content can move quickly, but retrieval must still be accurate.
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Retrieve
Rapid Recall Deck
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Say the answer aloud before flipping. Mark secure knowledge quickly and spend time on the gaps.
- What are the main parts of a control-system loop?: Input, processing, output, and—when present—feedback.
- What does a sensor do in a control system?: It measures a physical condition and provides input data to the controller.
- What does an actuator do?: It converts a control signal into a physical action, such as moving a motor or opening a valve.
- What is the difference between open-loop and closed-loop control?: Open-loop control acts without using feedback about the result; closed-loop control measures the result and adjusts future actions using feedback.
- What is the role of the controller and control algorithm?: The controller runs the control algorithm to interpret inputs and decide which outputs/actuator actions are required.
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A1.3.6 + A1.3.7 · Learn
Core knowledge and application
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A1.3.6Describe
The use of the control system components
Operating systems coordinate resources and processes; control systems sense, decide and act in the physical world.
Exam moveGive a detailed, accurate account of what happens or what something is like.
Required detail 1The input, process, output, and feedback mechanism (open-loop, closed-loop)
Required detail 2Controller, sensors, actuators, transducers and control algorithm
Explain it without notes
Describe: The use of the control system components in the context of a computer running many tasks while controlling a smart device.
- The input, process, output, and feedback mechanism (open-loop, closed-loop)
- Controller, sensors, actuators, transducers and control algorithm
A1.3.7Explain
The use of control systems in a range of real-world applications
Operating systems coordinate resources and processes; control systems sense, decide and act in the physical world.
Exam moveGive the mechanism or relationship and make the reasons/causes explicit.
Required detail 1Examples may include autonomous vehicles, home thermostats, automatic elevator controllers, automatic washing machines, traffic signal control systems, irrigation control systems, home security systems, automatic doors
Explain it without notes
Explain: The use of control systems in a range of real-world applications in the context of a computer running many tasks while controlling a smart device.
- Examples may include autonomous vehicles, home thermostats, automatic elevator controllers, automatic washing machines, traffic signal control systems, irrigation control systems, home security systems, automatic doors
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Apply
Transfer to a new scenario
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ScenarioA computer running many tasks while controlling a smart device needs a design or technical decision related to today’s topic. Explain what matters and why.
- The input, process, output, and feedback mechanism (open-loop, closed-loop)
- Controller, sensors, actuators, transducers and control algorithm
- Examples may include autonomous vehicles, home thermostats, automatic elevator controllers, automatic washing machines, traffic signal control systems, irrigation control systems, home security systems, automatic doors
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Exam lens
Paper 1 practice
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Build the response before checking notesUse precise terminology and match the required depth.
- Describe: The use of the control system components in the context of a computer running many tasks while controlling a smart device.
- Explain: The use of control systems in a range of real-world applications in the context of a computer running many tasks while controlling a smart device.
Self-checkAnswer the exact command term. For explain, include mechanism/reason; for compare, pair criteria; for discuss/evaluate/justify, build supported reasoning and a conclusion.
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Homework
Finish the learning cycle
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IA — main task
Finish Criterion D evidence: development documentation, testing evidence, video planning/recording and full source-code appendix.
Syllabus — short
Complete a short Paper 1 retrieval set based on today’s topic.
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End of Lesson 35.