DT topix 4 terms and defenitions

Strain

The response of a material due to stress, defined as the change in length divided by the original length

Stress

A force on a material divided by the cross sectional area of the material

Stiffness

The resistance of an elastic body to deflection by an applied force

Super alloy

Alloy that exhibits exceptional mechanical properties, resistance to thermal creep deformation, good surface stability and resistance to erosion

Synthetic fibres

Fibers made from man made materials, spun into threads- the joining of monomers into polymers through polymerization

Tempering

Heat treating process that increases the toughness of iron based metals by heating the metal and allowing it to cool in air- increase ductility and decrease brittleness

Knots

Imperfections in timber, caused by the growth of branches in the tree that reduces its strength

Lace making

A method for creating a decorative fabric that is woven into symmetrical patterns and figures

Laminated boards

Sheets of material made from layers of veneers (plywood)

Laminated object manufacture

A rapid prototyping system that creates a 3D product by converting it into slices, cutting the slices and joining the slices- grain at 90 degrees for extra strength

Lamination

Covering the surface of a material with a thin sheet of another material for protection, preservation or aesthetic reasons

Load capacity (robots)

The weight a robot can manipulate

Machine to machine M2M

Wired or wireless communication between similar devices

Magneto-rheostatic

Smart property relates to fluid that can undergo a dramatic change in viscosity when exposed to a magnetic field

Man made timber

Engineered or composite wood, made by binding or fixing strands, particles of fibers, veneers of boards of wood together with adhesives or other fixing methods to create composite materials e.g. MDF, plywood, chipboard

Twisting

A distortion in which two ends of a material do not lie in the same plane

Mass

Amount of matter in a given volume

Mass customization

CIM system that manufactures products to individual customer orders. The benefits of economy of scale are gained whether the order is for a single item or for thousands

Mass production

Production of large amounts of standardized products on production lines, permitting a very high rate of production per worker

Material selection charts

Chart used to identify appropriate materials based on desired properties

Mechanical properties

Properties of a material that involve the relationship between stress and strain or a reaction to an applied force

Multitask robots

A type of robot that can perform more than one task in a manufacturing environment

Automated production

A volume production process involving machines controlled by computers

Bio-compatibility

Ensures the continued health of a biological environment

Brittle

Breaks into numerous sharp shards

Design for disassembly

Designing for when the product becomes obsolete it can easily and economically be taken apart, the components reused or repaired and the materials recycled.

Design for materials

Designing in relation to materials during processing

Design for process

Designing to enable the product being manufactured using a specific manufacturing process, e.g. injection moulding

Dry rot

When timber is subject to decay and attacked by fungus

Ductitlity

The ability of a material to be drawn or extruded into a wire or another extended shape

Elasticity

The extent to which a material will return to its original shape after being deformed

Electrical insulator

Reduces transmission of electric charge

Electrical resistivity

The measure of a materials ability to conduct electricity- low resistivity will conduct well

Electro rheostatic

Smart property relates to a fluid that can undergo a dramatic change in its viscosity when exposed to an electric field

Equilibrium moisture content

EMC is at which the moisture content of wood achieves an equilibrium with the environment which can be affected by humidity and temperature

Felting

A method for converting yarn into fabric by matting the fibres together

First Generation robots

A simple mechanical arm that has the ability to make precise motions at high speed- need constant supervision by human operator

Free moisture

The moisture within timber that is contained within the cell cavities and inter cellular spaces

Glass

A hard, brittle and typically transparent amorphous solid made by rapidly cooling a fusion of sand, soda and lime

Grain size- metals

Metals are crystalline strucutres comprised of individual grains. Grain size can vart and be determined by heat treatment, particularly how quickly it cools . Quick cooling results in small grains. Slow cooling results in large grains- size can affect the density, tensile strength and flexibiltiy

Design for manufacture

Designers specifically design for optimum use of existing manufacturing capability

Craft production

Small- scale production process centered on manual skills

Design for assembly

Taking into account for assembly at various levels, e.g- component to component, components into sub-assemblies and sub-assemblies into complete products

Creosote

A material that penetrates the timber fibres protecting the integrity of the wood from borer, wood lice and fungal attack

Density

Mass per unit volume of a materials ability- portability in terms of weight and size e.g. packaged food sold in weight and vulme, packaging forms

Cupping

A warp across the width of the faces of wood, in which the edges are higher or lower than the centre

Continuous flow

Production method used to manufacture, produce or process materials without interruption

Creep

Slow, permanent deformation of a solid material under the influence of a mechanical stress

Computer numerical control CNC

CNC for the purpose of manufacturing complex parts in metals and other materials- controlled by G-code. Each code is a particular operation or process. Codes control XYZ movements and feed speeds

Compressive strength

The ability of a material to withstand being pushed or squashed

Composite

A material composed of two or more constituent materials that have different properties

Chemically inert

Lack of reactivity with other materials

Bowling

A warp along the edge of a face of the wood

Batch production

Limited volume production ( a set number of items to be produced )

Tensile strength

Ability of a material to withstand a pulling force

Assembly line production

A volume production process where products and components are moved continuously along a conveyor. As the product goes from one work station to another, components are added until the final product is assembled

Thermal expansion

Measure of the degree of increase in dimensions when an object is heated. This can be measured by an increase in length, area or voumet. Can be found in fractional increase per kelvin

Work envelope

A fixed 3d space where work activities take place, considering clearance and reach

Work hardening

Strain hardening or cold working, this is the process of toughening a metal through plastic deformation

Subtracting/ wasting techniques

Manufacturing technique That cuts away material to create a component

Yarn

A long continuous length of inter locked synthetic or natural fibres

Young’s modulus

A measure of stiffness of an elastic material and defined by stress/ Strain

Thermo electricity

Smart matrial that when heated can produce an electric current. Comprised of two dissimilar conductors

Wood treatment

Treatment of wood can involve using solution which make the wood poisonous to insects, fungus, and marine borers as well as protecting it from the weather

Volume

The quantity of a three dimensional object enclosed by a boundary- the space an object takes up

Warping

A distortion in wood caused by uneven drying, resulting in material bending or twisting

Third gen robots

Autonomous robots that can operate without supervisioj. Own cental control until. Swarms of small units fit in this category.

Transparency

Ability to allow light to pass through it with minimal distortion

Toughness

Ability to resist the prorogation of cracks

Thermosetting plastic

A plastic that when it takes its shape will permanently stay in that shape

Wood recycling

Process of turning waste timber into useable products. Recycling timber popularized in 1990s as of climate change and deforestation prompted timber suppliers and consumers to turn to a more sustainable timber source

Thermoplastic

A plastic that when heated can be reshaped and reformed

Thermal conductivity

Measurement of how fast heat will transfer through material with a given temperature

Weight

Relies on mass and gravitational forces to provide measureable value. Measure of a force

Additive techniques

Manufacturing techniques that add material in order to

Alloy

A mixture of that contains at least two metals. This can be a mixture of metals or a mixture of metals and non metals

Kiln seasoning

Thermally insulated chamber, an oven, which produces temperatures sufficient to complete some process, such as hardening, drying or chemical changes

Knitting

Converting yarn into fabric by creating consecutive rows of interlocking yarn loops

Piezoelectric

Smart material property, a siezoelectric material gives off a small electrical discharge when deformed

Weaving

The act of forming a sheet like material by interlacing long threads passing in one direction with other at a right angle to them

Aesthetic characteristics

Aspects of a product that relate to tastes, texture, smell and appearance

Air-drying

Stacks sawed timber in the open or in large shed hence there is little control over the drying process of the wood, will warp the wood

Physical properties

Any property that is measureable that describes state of materials for example, mass, weight, volume and density. Non-destructive testing (expect for hardness)

Plasticity

The ability of a material to be changed in shape permanently

Reforestation

The process of restoring tree cover to areas where woodlands or forest once existed. If this area never returns to its original state of vegetative cover the destructive process is deforestation

Seasoning

Commercial drying of timber which reduces moisture content of wood

Second generation robots

Robots equipped with sensors that can provide information about their surroundings. Can synchronise with each other and do not require consistent supervision by humans, controlled by an external control unit

Shape memory alloys

Metals that can be deformed, can spring back into original shape once released

Shaping techniques

Manufacturing methods for modifying the shape of a material

Single task robots

Robots that can only perform one task

Smart materials

Designed to have one or more properties that can be modified when subject to external stimuli in a way that the output can be controlled

Softwood

Coniferous tree

Pultrision

A continous manufacturing process used to create composite materials that have a constant cross section. Reinforcing fibres are saturated with a liquid polymer resin and then pulled apart through a heated die to form a part

Natural fibres

Materials produced by plants or animals that can be spun into a thread, rope or filament

Non-toxic

Absence of toxic breakdown breakdown products/ lack of reactivity

One off production

An individual article or prototype for larger scale production

Oxidation resistance

A property of a metal that means it does not readily react with oxygen and degrade

Paper- based rapid prototyping

Often the first step ina rapid prototyping, paper prototyping is used in UCD for designing and testing interfaces