Robotics
Automated and Emerging Technologies · 4 question types
Exam Frequency Analysis
Past paper frequency (2018 to 2024)
This topic accounts for approximately 3% of your exam marks.
Advantages/disadvantages of using robots in industry are the typical question format.
A robot is built from the same components covered in topic 15 (automated systems), with one extra category specific to robotics: the .
Sensors
Sensors are the robot's input devices, measuring the environment so the robot knows what is around it.
Typical sensors on a robot:
- Cameras and vision sensors: let the robot see objects, read text, recognise shapes.
- Proximity / distance sensors: detect how far away nearby objects are (ultrasonic, infrared, LIDAR).
- Touch / pressure sensors: tell the robot when it has gripped or bumped into something.
- Position / encoder sensors: report the angle of each joint or the distance each wheel has rotated.
- Temperature, light, gas, humidity sensors: depending on the task.
Microprocessor
The microprocessor is the robot's brain. It reads the sensor inputs, runs the program, and decides what each actuator should do next.
Modern robots may use a single microcontroller for simple tasks or a network of processors with onboard AI accelerators for complex perception and decision-making.
Actuators
turn the microprocessor's electrical signals into physical motion.
Common actuators in robots:
- Electric motors for wheels, joints and rotating tools.
- Servos for precise angular position (e.g. controlling each finger of a gripper).
- Hydraulic or pneumatic cylinders for heavy lifting in industrial robots.
- Solenoids for snap-action switching of small mechanisms.
End-effectors
An end-effector is the tool or hand at the end of a robot arm: the part that actually interacts with the world.
Examples of end-effectors:
- A gripper or claw to pick things up.
- A suction cup for handling flat or fragile objects.
- A welding torch, paint sprayer or drill for industrial tasks.
- A scalpel or laser scalpel on a surgical robot.
- A screwdriver on an assembly robot.
The same robot arm can often swap between different end-effectors to do different jobs, which is part of why a single industrial robot can be reprogrammed for many tasks.
Putting the components together
The data flow inside a robot is the same closed-loop pattern as any automated system:
sensors → microprocessor → actuators (turning end-) → environment changes → sensors read again
The environment changes because the end-effector did something; the sensor picks up that change on the next reading; the microprocessor decides what to do next. The cycle repeats many times a second.
Explaining how a robot responds to a detected condition
What comes up: A question gives you a robot (or automated system) and a trigger condition, then asks you to explain the role of the sensor, microprocessor and actuator — typically worth 3–6 marks.
Write (three core marks): (1) The sensor continuously reads the environment and sends digitised data to the microprocessor. (2) The microprocessor compares that data against a stored threshold or reference value; if the condition is met (e.g. an object is within range), it sends a signal to the actuator. (3) The actuator carries out a physical action (stops the motor, closes a door, etc.); if the condition is not met, no action is taken, and the process repeats until it is turned off.
Watch out: Vague answers like "the sensor detects it and the robot stops" score nothing on their own. You must chain all three components in sequence — sensor reads → microprocessor compares → actuator acts — and state what happens in both the triggered and the non-triggered case to reach full marks.