The 40 Inventive Principles are the clever ways the world has found (so far) to solve contradictions. For example, one kind of contradiction is that you want something big and small – you might want something small at one time, but then big at another time, such as a ship in a bottle which has to be small to get into the bottle but then big when it is inside. This is typically done using Inventive Principle No.15, Dynamism (the boat folds down small to get through the narrow bottle neck, and then can be unfolded when it is inside the bottle).
Another example is an umbrella, which you want big when it is raining and small at all other times. Contradictions have always existed, and people have always found clever solutions to them. However, what TRIZ has done has catalogued all the ways of solving contradictions and distilled them down into a list of simple but clever concepts – the 40 Inventive Principles! If you want to read more about contradictions and the 40 Inventive Principles, check out Chapter 3.
Each of the 40 Inventive Principles has a number of flavours or suggestions; for example, Inventive Principle No. 1 suggests three ways your system can be segmented. This appendix includes all the Inventive Principles with technical, management and general examples of these principles put into practice.
Inventive Principle 1: Segmentation
Divide an object into independent parts
Flat-pack furniture
Segmented tent poles
Sales teams have different markets/geographical areas
Make an object easy to take apart
Quick-release bicycle wheels
Use contract workers instead of permanent employees
Make the object even more fragmented or segmented
Many small, local offices rather than one large HQ
Telecommute: employees work from home
Inventive Principle 2: Taking Out
Take out a problem
Air conditioning in the room, noise elsewhere
Light pipes: get light where needed without heat
Only get what you need
Scarecrow
Buy-in expertise
No-frills hotel
Inventive Principle 3: Local Quality
Change an object from uniform to non-uniform
Ergonomic knife handles
Offer different products or use different marketing strategies for different geographical markets
Change the environment from uniform to non-uniform.
Working hours phased to accommodate people working on international, shifted time-zone projects
Make each part of an object function in conditions most suitable for its operation
Night-time adjustment on rear-view mirror
Make each part of an object fulfil a different and useful function
Hammer with nail-puller
Inventive Principle 4: Asymmetry
Change the shape of an object from symmetrical to asymmetrical
Funnel with off-set exit for faster flow rate
Use a different marketing approach for different types of clients
Change the shape of an object to suit external asymmetries
Ergonomic running shoes
If an object is asymmetrical, make it more asymmetrical
Different running shoes to suit users’ running styles
Inventive Principle 5: Merging
Join objects or operations together
Bi-focal lenses
Crew members in McDonalds
Join parallel operations in time
Include your customers and suppliers in design phase
Work on a project in parallel rather than in series
Inventive Principle 6: Multi-Function
Make an object perform multiple functions; eliminate the need for other objects.
Swiss Army Knife
‘One-stop shopping’ – supermarkets sell insurance, banking services, fuel, newspapers and so on.
Inventive Principle 7: Nested Doll
One object is placed inside another; which, in turn, is inside another, and so on.
Shopping centres/malls
Nested tables
Measuring cups or spoons
One object passes through another
Telescopic car aerial
Tape measure
Inventive Principle 8: Counterweight
Compensate for the weight of an object by joining it with another object which provides lift.
Hot-air balloons
Kayaks with integrated foam floats
Build teams of different personality types
Compensate for the weight of an object by making it interact with the environment
Maglev trains use magnetic levitation to create lift and propulsion, reducing friction and allowing for higher speeds
Use renewable energy to reduce a company’s carbon footprint
Boost popularity by connecting with popular causes; for example, charities
Inventive Principle 9: Prior Counteraction
Add a counteraction to manage a downside
Make clay pigeons out of ice or clay
Off-set carbon emissions
Give generous severance packages when making redundancies
Create beforehand stresses in an object that will oppose known undesirable working stresses later on
Pre-stressed concrete compensates for concrete’s weakness in tension
Ergonomically assess workstations
Inventive Principle 10: Prior Action
Do a required action in advance
Practise emergency procedures in advance of crisis
Agree meeting agendas in advance
Arrange objects conveniently so they can go into action without loss of time
Just-In-Time production
In-store bakeries
Inventive Principle 11: Cushion in Advance
Prepare emergency means beforehand to compensate for the relatively low reliability of an object
Back up computer data
Contingency planning
Have more than one person trained in skills critical to the company
Inventive Principle 12: Equal Potential
Change the conditions of work so that an object doesn’t need to be raised or lowered
Mechanic’s pit in garage (car isn’t lifted)
Grow the job rather than promote the person
Inventive Principle 13: The Other Way Round
Do the opposite action
Cash-back in stores: customers take money away instead of security firms
Make movable parts fixed, and fixed parts movable
Home-shopping
Treadmills
Wind tunnels
Turn the object upside down
Customers create their own product, for example, radio listeners dialling in for talk shows or to give traffic updates
Tomato sauce bottle with opening on the bottom
Inventive Principle 14: Spheres and Curves
Switch from flat surfaces to spherical ones; from parts shaped as cubes or rectangles to ball-shaped structures
Mezzaluna (knife shaped as a half-moon)
Arches and domes for strength in architecture
360-degree appraisals
Use rollers, balls, spirals, domes
Rotary pizza cutter
Ballpoint pens
Archimedes screw
Make repeat purchases easy (such as direct debits, subscriptions)
Go from linear to rotary motion, use centrifugal forces
Push–pull to rotary switches (for example, lighting dimmer switches)
Loyalty schemes
Inventive Principle 15: Dynamism
Change the object or environment to work the best at every stage of work
Adjustable steering wheel (or seat, back support, mirror position and so on)
Different price and positioning for products throughout their life
Divide an object into parts that can move relative to each other
Bifurcated bicycle saddles
Folding chairs
If an object is rigid, make it movable
Bendy drinking straw
Hot-desking
Virtual 360-degree tours online
Inventive Principle 16: Partial or Excessive Action
If it’s difficult to get 100 per cent of an action, go for more or less
Overfill bottles on production line
Overspray when painting, then remove the excess
Ensure happy customers by providing exceptional customer service
Show products and services online even if it’s not possible to purchase online
Inventive Principle 17: Another Dimension
Move to another dimension: from one to two or three dimensions
Coiled telephone wire/garden hose
Go from a single layer to multi-layers
Multi-storey car park
Hierarchy of command
Tilt an object or turn it on its side
Cars on road transporter inclined to save space
Use the other side of an object
Print on both sides of paper
Electronic components mounted on both sides of circuit board
Inventive Principle 18: Mechanical Vibration
Make an object vibrate
Electric toothbrushes
Increase the frequency of vibration (up to ultrasonic)
Sonic toothbrushes
Sonic facial brushes
Use an object's resonant frequency
Break up kidney stones with ultrasound
Tuning fork
Use piezoelectric vibrators instead of mechanical ones
Quartz watches
Use combined ultrasonic and electromagnetic field oscillations together
Ultrasonic and electromagnetic pest repellers deter both mice and insects
Inventive Principle 19: Periodic Action
Go from continuous action to periodic or pulsating actions
ABS brakes
Flashing bicycle lights
Change leadership: many university heads of department only lead for a year, senior academics rotate leadership
If an action is already periodic, change the rate or level of change
Appraise performance more regularly than annual reviews
Use pauses between actions to perform a different action
Perform maintenance work during slow periods
Inkjet printer cleans head between passes
Inventive Principle 20: Continuous Useful Action
Carry out work without a break
24-hour manufacturing
Hospital emergency departments
Remove idle or intermittent actions
Kayaks use double-ended paddle to utilise recovery stroke
Multi-skill workforce to enable them to perform other tasks when their core job has quiet periods
Inventive Principle 21: Rushing Through
Do a process, or certain stages (which are harmful or dangerous) at high speed
Cut plastic faster than heat can propagate in the material, to avoid deforming the shape
Immediate dismissal
Inventive Principle 22: Blessing in Disguise
Use harmful factors (particularly, harmful effects of the environment) to get something good
Pain can be useful feedback to stop doing something; for example, walk on broken ankle
Remove a harmful action by adding another harmful action
Reduce traffic in cities by introducing a congestion charge
Increase a harmful factor so much that it is no longer harmful
Restrict supply of goods to create scarcity value (such as designer handbags)
Inventive Principle 23: Feedback
Introduce feedback
Customer surveys
Feedback forms after training
Exercise apps that inform you of distance run, average speed, calories burned
If feedback is already used, make it more effective
Go from paper feedback forms to interviews or online surveys
Share information from exercise apps on social media
Inventive Principle 24: Intermediary
Use an intermediary object to pass on an action
Play guitar with a plectrum
Marriage counsellor
Travel agent
Temporarily join an object with another (easily removable)
Oven gloves for hot dishes
Bridging loans
‘The A-Team’
Inventive Principle 25: Self-service
An object services, maintains and repairs itself
Self-cleaning ovens
Wikipedia
Customer loyalty reward schemes (such as Nectar cards) collect information about individual’s purchasing decisions to target services and products
Bicycle tyres filled with gel to seal punctures instantly
Use waste (or lost) resources, energy or substances.
Use heat from a process to generate electricity (co-generation)
Use travel time to work
Inventive Principle 26: Copying
Replace unavailable, expensive, complicated, fragile objects with cheap, simple copies
Scan rare, historic books and documents, so they are accessible to all and the original remains protected
Replace an object, or process with optical copies
Measure an object from a photograph
Product manuals as PDFs rather than printed booklets
Online training instead of classroom training
If visible optical copies are used, move to infrared or ultraviolet; use unusual ways of seeing/viewing situations
Police helicopters use infrared to track suspects
Evaluate customer satisfaction in multiple ways, for example, interviews, questionnaires, observing customers use product
Replace an expensive object with many inexpensive objects that don’t last as long
Disposable serviettes, napkins, cups, cameras
Automate work procedures and have low-skilled, low-paid staff who are easily replaceable
Make product cheap and easily replaceable instead of reusable, for example, contact lenses, nappies, low-cost clothes
Inventive Principle 28: Replace Mechanical System
Replace a mechanical system with a sensory one (optical, acoustic, taste or smell)
Lights and bells rather than secure barriers at rail crossings
Smell of baking bread to entice shoppers
Security systems
Use electric, magnetic and electromagnetic fields to interact with the object; use influence instead of rules
Magnetic bearings
TV remote control
Use staff loyalty to encourage good behaviour
Replace stationary fields with moving unstructured fields; replace unstructured fields with structured ones
Hot desking
GPS sensors inform central control point of location of delivery vans, taxis
Use fields in conjunction with field-activated (such as ferromagnetic) particles
Ultrasonic welding
Inventive Principle 29: Pneumatics and Hydraulics
Use gas and liquid parts of an object instead of solid parts (for example, inflatable, filled with liquids, air cushion, hydrostatic, hydro-reactive); use flexible influences instead of solid rules
Inflatable mattresses
Hovercraft
Use guidelines, not rules
Create a ‘health and safety culture’ instead of a long list of rules
Inventive Principle 30: Flexible Membranes and Thin Films
Use flexible shells and thin films instead of three-dimensional structures
Tarpaulin car cover instead of garage
Open-plan offices
Isolate the object from the external environment using flexible shells and thin films
Bubble-wrap
Bandages and plasters
Offices with cubicles
Inventive Principle 31: Porous Materials
Make an object porous or add porous elements (inserts, coatings and so on)
Cavity wall insulation
Foam metals
‘Open door’ management policies
If an object is already porous, use the pores to introduce a useful substance or function
Medicated dressings
Train customer service teams to sell additional products and services (for example, at shop tills)
Inventive Principle 32: Colour Change
Change the colour of an object or its surroundings
Colour-changing paint or sun cream
Light-sensitive glasses
Change the transparency of an object or its surroundings
Make organisation’s objectives and decision-making processes clear to everyone
Transparent solar cells (make every window/screen a photovoltaic solar cell)
Observe objects or processes that are hard to see by using coloured additives
Use opposing colours to increase visibility (for example, butchers use green decoration to make meat look redder)
If additives are already used, monitor things that are hard to see by adding luminescence/other markers
UV marker pens to identify stolen goods (only seen under ultraviolet light)
Get potential customers to register interest with special offers
Inventive Principle 33: Uniform Material
Objects interacting with the main object should be made of the same material (or one with similar properties)
Ice cubes made of drink they are cooling (such as lemonade)
Wood dowel joints for joining wooden components
Make sure all your employees can understand and sell your products
‘Mirror’ someone’s body language to facilitate easy communication
Inventive Principle 34: Discarding and Recovering
Make objects (or part of them) that have fulfilled their useful functions go away (discard by dissolving, evaporating and so on) or modify them directly during operation
Dissolving capsules for vitamins and medicine
Bio-degradable containers and bags
Take on temporary staff to manage busy periods, such as in shops over Christmas
Restore consumable parts of an object during operation
Sell on to ‘used up’ customer: for example, transfer student bank accounts to graduate bank accounts when they finish their course; dentists refer patients to dental hygienists
Self-sharpening blades
Mechanical pencil
Inventive Principle 35: Parameter Change
Change the physical state (for example, to a gas, liquid or solid)
Transport gases as liquids
Liquid soap instead of soap bar
Deodorant as a liquid, solid stick or aerosol spray
Virtual organisations
Customer service offered remotely (by phone or chat box online) instead of face to face
Change the concentration or density
Change number of staff
Fire briquettes: low density for lighting fires, high density for burning all night
Move from local to centralised distribution (or vice versa)
Change the degree of flexibility
Vulcanised rubber is less flexible and stronger
Hot-desking
Flexi-time
Change the temperature or volume
‘Fire up’ and motivate employees
Increase individual’s scope of responsibility
Heated butter knives and ice cream scoops
Butter knives with built-in grater to soften cold butter
Change the pressure
Pressure cooking is faster
Manipulate stress levels (increase near deadlines)
Change other parameters
Semco: staff set their own wages, production targets, working hours
Thixotropic paints are viscous so they don’t drip, but become runny when shear force is applied by the brush against the surface being painted.
Inventive Principle 36: Phase Changes
Use phenomena occurring during phase changes (volume changes, loss of absorption of heat and so on)
Latent heat effects in melting or boiling
Break rocks by soaking in water and then freezing
Individuals try harder when proving themselves; for example, graduates, new to the post, newly promoted: use these people for difficult projects/those requiring long hours
Inventive Principle 37: Thermal Expansion
Use expansion (or contraction) of materials by heat; responsiveness to circumstances
Be very responsive to change; for example, have extra staff available for busy periods
Emergency services available to deal with crises
Shape memory materials
Shrink-wrapping
Use multiple materials with different coefficients of thermal expansion; use multiple and different systems that respond to circumstances differently
Bi-metallic strips used in thermostats
Different emergency services offer different expertise in major car crashes, for example, police create safe space on road and prevent other crashes; fire service to cut people out of cars; ambulance knows how to move injured people.
Inventive Principle 38: Boosted Interactions
Enrich the atmosphere
Create a competitive atmosphere to motivate sales team
Oxygen tent for asthmatic patients
Nitrous oxide injection for power boost in engines
Create the right atmosphere for different working environments: places with buzz for team working and discussing ideas; quiet zones for independent working
Create a highly enriched atmosphere
Use highly charismatic leaders to engage the workforce
Irradiation of food to extend shelf life
Enrich the atmosphere with unstable elements
Staff charged with energy through uncertainty: such as fear (threat of redundancy) or rewards (bonuses/promotion)
Use ozone to destroy micro-organisms
Inventive Principle 39: Inert Atmosphere
Replace a normal environment with an inert one
Libraries’ quiet environment creates a good environment to work, read and study
Corporate away days
Foam to separate a fire from oxygen
Add neutral parts or inert additives to an object
Use contractors and external consultants
Fire retardant additives
Inventive Principle 40: Composite Structures
Change from uniform to layered/composite (multiple) structures
Teams with diverse team members bring different skills and perspectives
Use different delivery methods in training (lectures, exercises, follow-up reading)
Fibre-reinforced composite materials in Boeing 787 wing and fuselage