MATSEC SEC Design and Technology flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Design brief

A short statement of the problem, client needs and main constraints that starts a design project, written before detailed research and later expanded into a measurable specification.

Design specification

A list of testable criteria such as dimensions, cost, materials, safety and performance that a proposed solution must meet, used to compare concepts and evaluate the final product.

Formative evaluation

Continuous testing during development, including models, mock-ups and user trials, that identifies faults early so the design can be changed before manufacture begins.

Anthropometric data

Measurements of human body size and reach, usually given as percentiles, used to size products so most users can operate them comfortably and safely.

Hardwood versus softwood

Hardwoods come from broad-leaved deciduous trees such as oak and ash; softwoods come from conifers such as pine. The terms describe tree type, not timber hardness.

Thermoplastic

A polymer that softens when heated and can be reshaped repeatedly, making it recyclable. Examples are acrylic, HDPE, PVC and ABS, used for packaging and moulded parts.

Thermosetting plastic

A polymer whose molecular chains cross-link permanently when cured, so it cannot be remelted. Examples include epoxy resin, polyester resin and melamine, used where heat resistance matters.

Toughness

The ability of a material to absorb impact energy without fracturing. Tough materials deform before breaking, unlike brittle materials such as cast iron or glass.

Density formula

Density equals mass divided by volume, measured in kilograms per cubic metre. It explains why equal-sized parts in aluminium and steel differ greatly in weight.

Marking gauge

A woodworking tool with a sharp pin or knife set at a chosen distance from a stock face, used to scribe lines parallel to an edge for joints and rebates.

Bench drill safety

Clamp the workpiece, remove the chuck key before starting, set a speed suited to the bit and material, wear eye protection and never wear gloves near rotating tooling.

File card

A stiff brush with short wire bristles used to clean metal swarf out of file teeth, keeping the file cutting efficiently and preventing scratching of the workpiece.

Injection moulding

A high-volume process in which softened thermoplastic is forced into a closed steel mould, producing accurate identical parts quickly once the expensive tooling has been made.

Vacuum forming

A process where heated thermoplastic sheet is drawn over a mould by suction, used for cheap trays, packaging and guards; it leaves a web that must be trimmed.

Mortise and tenon joint

A strong frame joint where a projecting tenon on one piece fits a matching mortise hole in another, usually glued and sometimes pinned with a dowel.

Quality control

Inspection and measurement of finished parts against specified tolerances, rejecting or reworking any item that falls outside the permitted limits.

Third-angle projection

An orthographic layout in which the plan view is placed above the front view and the end view appears on the side from which it is viewed, standard in the UK.

Isometric drawing

A 3D pictorial drawing using vertical lines and two axes at 30 degrees to the horizontal, with all edges drawn at true length along those axes.

Section view

A drawing that shows a component as if cut through, with cut surfaces hatched at 45 degrees, revealing internal features such as holes and cavities.

Drawing scale

The ratio between the drawn size and the real object, shown in the title block. Dimensions always state true size whatever scale is used.

Mechanical advantage

The load a machine can move divided by the effort applied. It is calculated from forces, while velocity ratio is calculated from distances moved.

Gear ratio

The number of teeth on the driven gear divided by the number on the driver gear; a ratio above one reduces output speed and increases output torque.

Moment of a force

Force multiplied by the perpendicular distance from the pivot. A lever balances when total clockwise moments equal total anticlockwise moments.

Triangulation

Bracing a frame with diagonal members to form triangles, which prevents the structure from racking and makes it rigid under load.

Ohm's law

Voltage equals current multiplied by resistance, written V = I x R. Combined with P = V x I it allows unknown values in a simple circuit to be calculated.

Potential divider

Two resistors in series across a supply, where output voltage equals input voltage times the second resistance divided by the total resistance.

Light-dependent resistor

An input component whose resistance falls as light intensity rises, used with a resistor or transistor to switch lamps or alarms at dusk.

LED series resistor

A resistor placed in series with a light-emitting diode to limit current, calculated from supply voltage minus the diode forward voltage, divided by the desired current.

Sankey diagram

A flow diagram with arrow width proportional to energy, showing useful output and losses such as heat at each stage of an energy transfer.

Life cycle assessment

A structured review of a product's environmental impact from raw material extraction through manufacture, distribution, use and end-of-life disposal or recycling.

Embodied energy

The total energy consumed in extracting, processing and manufacturing a material or product, used to compare the environmental cost of material choices.

Design for disassembly

Designing products with reversible fixings and labelled, separable materials so that parts can be repaired, reused or recycled at end of life.

Inclusive design

Designing products that as many people as possible can use regardless of age or ability, following principles such as equitable use, flexibility and tolerance for error.