MATSEC SEC Design and Technology key terms

A short written statement from a client or user setting out the problem to be solved, the intended user and the main constraints, before any sketching or research begins.

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

The individual points in a specification against which competing design ideas are compared and scored, so that the choice of a final solution can be justified.

Any limit placed on a design, such as a maximum budget, available machinery, safety rules or a fixed overall size, which rules out some possible solutions.

Working in repeated cycles of sketching, modelling, testing and improving, so that each version of a product is informed by the weaknesses found in the previous one.

A structured judgement of a finished design or prototype, comparing its measured performance against the specification and recording strengths, weaknesses and suggested improvements.

The study and measurement of human body sizes and reach, used to decide dimensions such as seat height, handle position or worktop level so products fit real users.

The practice of designing products and workplaces to match human capabilities, reducing strain and fatigue by considering posture, force required, reach and repeated movements.

A statistical measure showing the percentage of a population below a given body dimension; designers often use the 5th percentile for reach and the 95th for clearance.

Timber from broad-leaved, usually deciduous trees such as oak or beech; it is generally denser and slower growing than softwood but the term does not strictly mean harder.

Timber from coniferous trees such as pine, spruce or cedar; it grows quickly, is usually cheaper and lighter, and is widely used for building frames and general joinery.

Controlled drying of timber, either in air or in a kiln, to lower its moisture content so that shrinkage, warping and splitting are reduced after the wood is worked.

A polymer that softens when heated and can be reshaped repeatedly, making it suitable for recycling and for processes such as vacuum forming and injection moulding.

A polymer that cures permanently when heated or mixed with a catalyst and cannot be remelted, giving good heat resistance and rigidity but making recycling difficult.

A material made by combining two or more different materials so the finished product has properties better than either part alone, such as glass-reinforced plastic or plywood.

A metal made by melting and mixing two or more elements, for example brass from copper and zinc, to improve strength, corrosion resistance or casting behaviour.

A metal that contains iron as its main element, such as mild steel or cast iron; most are magnetic and many will rust unless protected by a coating.

A metal containing no significant amount of iron, such as aluminium, copper or zinc; these resist rusting and are often chosen for lightness or electrical conductivity.

Joining thin layers of material with adhesive or heat so that the layers build up thickness and strength, as in plywood or laminated veneer lumber.

A workshop device that holds work or guides a tool in a fixed position so that repeated identical operations, such as drilling holes in the same place, can be carried out accurately.

The checks and measurements made during and after production to confirm that parts and finished products meet the specification, with faulty work identified and corrected.

The permitted amount by which a dimension may vary from its stated value, allowing parts to be made economically while still fitting together during assembly.

A mass-production process in which softened thermoplastic is forced under pressure into a closed steel mould, giving accurate, repeatable parts with little finishing needed.

A slight taper built into the sides of a moulded or cast part so that it can be removed from the mould without scuffing the surface or becoming trapped.

A drawing method showing an object from several directions at right angles, usually front, side and plan views, laid out so that each view is aligned with the others.

A pictorial drawing in which the three main axes are set at 120 degrees to each other, giving a three-dimensional view with all vertical lines drawn true and no perspective.

A drawing in which every dimension is reduced or enlarged by the same fixed ratio, stated on the sheet, so real sizes can be read directly from the paper.

Computer-aided design: using software to build, edit and store accurate 2D drawings or 3D models, which can then be rendered, analysed or sent to a machine.

Computer-aided manufacture: using computer-generated instructions, often from a CAD model, to control machines such as routers, lathes or laser cutters in production.

Producing a physical model directly from a CAD file in hours rather than days, typically by additive methods such as fused deposition modelling, to test shape and fit.

A first working or non-working model built to test an idea, check dimensions and gather user feedback before committing to production tooling.

An assembly of linked parts that changes the direction, speed or size of a movement, for example a lever, pulley system, gear train or crank and slider.

The ratio of the load a machine can move to the effort applied to it; a value above one means a smaller effort lifts a larger load.

The relationship between the numbers of teeth on two meshing gears, which sets how many turns the output makes for each turn of the input and so changes speed and torque.

A framework that carries loads without moving, such as a bridge or chair frame; its strength depends on triangulation, material choice and sound joints.

Bracing a framework with diagonal members to form triangles, which stops the frame distorting under load and is the basis of stiff, economical structures.

The relationship stating that voltage equals current multiplied by resistance; it lets a designer calculate the resistor needed to protect a component in a circuit.

Two ways of connecting components: in series they share one path so current is the same and voltages add, while in parallel they share voltage and currents add.

A component that limits or divides current in a circuit, with its value in ohms shown by a colour code or printed marking, often used to protect LEDs.