All DT Key Terminology Flashcards
Collaborative design
Working with others, especially at the development stage. Promotes motivation, problem solving, communication and support.
User-centred design
Focus is on the user or client for every stage of the design. It includes observation of the user, continuous consultation and testing.
Systems approach
Sequences of actions used in the design process. This is a linear process relying on inputs, processing and outputs.
Iterative design
Making and testing a product, then evaluating its successes and failures before redesigning with improvements and repeating this process.
Planned obsolescence
The deliberate designing of a product to fail prematurely.
Perceived obsolescence
A product going out of fashion therefore becoming less desirable.
Design fixation
Loss of innovation or creativity in designs due to the influence of existing ideas.
Sketching
Producing a rough record of ideas.
Modelling
Producing a simple physical translation of an idea.
Non-destructive testing
Testing without harming the subject.
Destructive testing
Testing a product until it fails to see how much wear it can take.
Market testing
The target market testing the product to see its effectiveness.
Name 6 circuit inputs:
Toggle switch; push to make; push to break; light dependent resistor; thermistor; pressure switch
Name 5 circuit outputs:
Light emitting diode (LED); lamp; buzzer; speaker
Analogue signal
A signal with an infinite amount of values along a range.
Digital signal
A signal that is either on or off, often represented by 1 or 0 correspondingly.
Monostable circuit
A circuit that will switch on once, but once turned off, will stay off.
Astable circuit
A circuit that is constantly alternating between on and off.
Name 7 modern materials and their properties;
Biodegradable polymers - made from vegetable starches, biodegradable alternatives to plastics;
Titanium - often alloyed with other metals, lightweight, very strong, doesn’t react with the body;
Fibre optics - carry light through a thin glass core, used in cable TV and broadband infrastructure, has medical applications such as endoscopes;
Graphene - uses are still being discovered and developed, could be used in flexible electronics or biomedicine, 200x stronger than steel;
Liquid crystal display (LCD) - screens can be very small and lightweight, can feature bespoke monochrome layouts, low power consumption, does not emit light, so requires back lighting;
Nano materials - very tiny materials used for small-scale parts, between 1 and 1000nm in size;
Metal foam - very lightweight compared to solid metal, 25% of the solid metal mass, made by injecting gas into aluminium or titanium, recyclable
What are the four types of motion?
Linear; reciprocating; oscillating; rotary
Name four cam shapes
Eccentric; pear; snail; heart
How do you work out mechanical advantage?
Load/effort
What is a first order lever?
Load - fulcrum - effort
What is a second order lever?
Effort - load - fulcrum
What is a third order lever?
Load - effort - fulcrum
Name 3 linkages
Reverse motion linkage; parallel motion linkage; bell crank linkage
How do you work out force required of a pulley system?
Force required = load/no. pulleys
How do you work out the speed and force ratios of gears?
The ratios of the teeth.
What is an idler gear?
A smaller gear placed between two others so the two turn in the same direction.
What are the names for the gear that is turning others and the gear that is being turned?
The drive gear and the driven gear.
What is a smart material?
A material that reacts to an external stimulus by changing their characteristics or properties.
Name 4 smart materials and what they react to
Self-healing polymers - can mend cracks in themselves as they react to air being introduced or a pressure change.
Thermochromic pigments - changes colour in specific temperatures.
Photochromic pigments - reacts with UV light to give off visible light.
Shape memory alloys (SMAs) - metals that can be deformed into different shapes, reacts to heat or electricity.
Name 5 renewable energy sources
Wind; solar; tidal; biomass; hydroelectric