LGCSE Design & Technology (0189) key terms

A repeating process of researching, designing, making and testing a product, where results from each evaluation feed back into the next round of improvements rather than following a single straight line.

A short statement from a client or designer describing the problem to solve, the intended user and any main constraints, without prescribing the final solution.

A detailed list of measurable requirements a product must meet, such as size, cost, materials, safety and performance, used to judge whether a design is successful.

A working or scaled model built to test how a design performs and feels, allowing faults to be found before committing to full production.

The study of how people interact with products and workplaces, used to shape sizes, grips and controls so that they fit the human body comfortably and safely.

The measurement of human body dimensions and reach, used as data when deciding sizes and clearances for products, furniture and workspaces.

A polymer that softens when heated and hardens on cooling, and can be reshaped repeatedly, which makes it easy to recycle and suitable for forming processes.

A polymer whose molecular chains cross-link permanently when cured, so it cannot be softened or remelted by heating and is hard to recycle.

A metal made by mixing two or more elements, at least one being a metal, to improve properties such as strength, hardness or corrosion resistance compared with the pure metal.

A metal or alloy containing iron as its main element, such as steel or cast iron; most are magnetic and many rust unless protected.

A metal that contains no significant amount of iron, such as aluminium, copper or brass, giving good corrosion resistance and electrical conductivity.

A material made from two or more distinct materials combined so their properties add together, for example glass fibres set in a resin to give strength with low weight.

A manufacturing process in which softened thermoplastic is forced under pressure into a closed metal mould, producing identical parts quickly once the tooling is made.

A process where a heated thermoplastic sheet is drawn down onto a mould by suction, copying the mould's shape on one side only.

Making a limited quantity of identical products in groups, using some shared tooling and standardised parts, balancing cost against flexibility.

A device that holds a workpiece and guides the tool to a set position, so repeated operations are accurate and quick.

The checks and measurements applied during and after manufacture to confirm products meet the specification, with faulty items rejected or reworked.

The acceptable amount by which a dimension may vary from its stated size, allowing parts to fit together reliably without being made impossibly exact.

The ratio of the load a mechanism can move to the effort applied to it; a value above one means the mechanism multiplies force.

A rigid bar that turns about a pivot, used to move a load with an effort; its class depends on where the pivot sits between effort and load.

The relationship between the tooth counts of two meshing gears, showing how many turns the input makes for each turn of the output and how torque changes.

Adding diagonal members to a frame so it forms triangles, which stops the frame distorting under load because triangles cannot change shape without changing side length.

A pulling force that stretches a material along its length, as in a cable carrying a hanging load.

A pushing force that squeezes a material along its length, as in a column carrying the weight of a structure above it.

Two resistors connected in series across a supply, giving an output voltage that is a chosen fraction of the supply, often used with a sensor.

The relationship stating that current through a conductor equals voltage divided by resistance, written V = I × R, used to calculate values in circuits.

A three-terminal semiconductor device that acts as an electronic switch or amplifier, allowing a small base or gate signal to control a larger current.

A control system that measures the actual output with a sensor and compares it with the required value, adjusting continuously to reduce any error.

A control system that carries out a set sequence without checking the result, so it cannot correct for changes or faults.

A diagram using standard symbols and arrows to show the steps, decisions and order of operations in a process or control program.

Computer numerical control: the use of coded instructions from a computer to drive machine tools, giving repeatable accuracy and complex shapes.

Computer-aided design: creating, editing and testing a product's geometry in software, allowing easy modification, simulation and sharing of drawings.

Producing a physical model directly from digital data, often by adding material layer by layer, so designs can be handled and tested quickly.

Designing a product so its parts can be separated easily at end of life, using fasteners rather than adhesives, so materials can be reused or recycled.

A study of the environmental impact of a product at every stage from raw material extraction through manufacture and use to disposal or recycling.

Designing products that meet present needs while limiting resource use and pollution, for example by choosing renewable materials, reducing energy in use and extending product life.

A drawing method showing a three-dimensional object as separate front, side and plan views arranged in a fixed layout, with hidden detail shown as dashed lines.

A pictorial drawing in which three axes are set at 120 degrees apart, showing three faces of an object at once without the distortion of perspective.

A fully dimensioned drawing giving sizes, materials, tolerances and assembly information so a product can be made by someone other than the designer.

A careful examination of a task to identify hazards, judge how likely and how serious harm could be, and record measures that reduce the risk.

Any source of possible harm in a workshop or product, such as a rotating cutter, trailing cable, sharp edge or toxic substance.

Personal protective equipment worn by the individual, such as goggles, ear defenders or a dust mask, to reduce exposure to hazards.