Robotics

A robot is a programmable mechanical machine that can interact with the real world. The three characteristics every robot has:

1. Mechanical structure. A physical body — frame, joints, wheels, treads, arms, grippers, drones — built to interact with the physical environment. The 'end effector' is the tool at the working end (gripper, welder, spray nozzle, drill).

2. Sensors. Inputs that capture information about the environment — vision (cameras), touch (force sensors), distance (ultrasonic, infrared, lidar), pressure, acceleration, GPS. Lets the robot perceive what's happening and react.

3. Programmable control. A microprocessor or controller running PROGRAMS that decide what to do based on sensor input. Crucially, robots can be REPROGRAMMED for different tasks — the same arm can switch from welding to bolting after a software update.

A pure conveyor belt is NOT a robot — no sensors, no programmability. A CNC machine is borderline (programmable but limited sensing). A robotic arm with vision and force feedback IS a robot.

Cambridge tip. Mark scheme rewards naming all three: STRUCTURE + SENSORS + PROGRAMMABILITY. Some mark schemes also reward 'reprogrammable for different tasks' as a bonus mark.

Real-world robotic applications are diverse:

Industrial / manufacturing.

• Robotic arms on car assembly lines (welding, spraying, fitting).
• Pick-and-place machines on circuit-board manufacturing.
• Warehouse-fulfilment robots (Amazon Kiva).
• Quality-control vision systems.

Medical.

• Surgical robots (da Vinci system) — surgeons operate consoles; robots translate to micro-precise instrument movements.
• Pharmacy automation — robotic dispensers count pills.
• Rehabilitation robots — exoskeletons help stroke patients relearn movement.

Agriculture.

• Robotic milking parlours.
• Planting and harvesting robots that move along rows.
• Drone fleets for crop spraying and monitoring.
• Strawberry-picking robots that visually identify ripe fruit.

Exploration.

• Mars rovers — semi-autonomous, navigate, take samples.
• Deep-sea ROVs — exploration, pipeline inspection, wreckage recovery.
• Disaster-response robots — search through rubble, defuse bombs.

Domestic.

• Robotic vacuum cleaners and mops.
• Robot lawnmowers.
• Pool-cleaning robots.

Military. Bomb-disposal, surveillance drones, autonomous patrol robots (with significant ethical debates around lethal autonomy).

Cambridge tip. When a question asks for examples, give DIFFERENT industries — repeating 'manufacturing' three times scores fewer marks than spreading the answer across industrial, medical and domestic.

Advantages.

• Operate in dangerous environments humans can't tolerate (chemicals, high heat, radiation, deep sea, space).
• 24/7 operation with no breaks, fatigue or shift changes.
• Greater precision — repeatable to micrometres. Crucial for surgery, electronics manufacture, scientific lab work.
• Higher productivity — assembly lines run faster than human workers can.
• Consistency — every part produced is identical to spec.
• No human-error fatigue — errors don't increase as the day goes on.

Disadvantages.

• Job displacement — repetitive manual jobs disappear. Affects whole communities; retraining costs are high.
• High upfront cost — robots, integration, programming, ongoing maintenance.
• Limited flexibility — most robots do what they're programmed to do; struggle with unexpected situations a human would handle naturally.
• Cyber-attack vulnerability — networked robots are targets.
• Loss of human skills — when robots take over, the relevant human skills atrophy. Hard to recover when the robots fail.
• Sensor / mechanical failure — when something breaks, the whole line can go down.

Cambridge tip. Top-band evaluation answers acknowledge that the COSTS of robotics aren't just monetary — they include social and human-skill costs.