Image Image Image Image Image Image Image Image Image Image
Scroll to top

Top

Super Stream Approach to TRIZ

| On 02, Nov 2009

By S. Saleem Arshad

Abstract

The super stream augmented approach (SSA) is proposed as a planning and structuring layer to enhance the application of Theory of Inventive Problem Solving (TRIZ) tools for sustained innovation.

The SSA is based on knowledge abstractions that encapsulate what is known about the system of interest along specific paths of inquiry. The separation of the paths of inquiry allows the modelling of multiple assumptions from the outset and provides for the macro level steering of solutions. Within each path or super stream are mechanisms to drill down into each assumption in detail. This provides a micro level analysis of solutions.

The utility of the SSA for sustained innovation is demonstrated by its application to an ongoing issue in aviation safety in regards to the generation of more than 25 concepts; each one is a conceptual advancement over the current state of practice in the aviation industry.

Keywords

Innovation, super stream augmented approach (SSA), TRIZ, innovation planning, aviation safety, entry vector (EV), functional streams (FS), solution vector (SV), solvecs, sustained innovation

Proposed Definitions for SSA

  • Innovation: the systematic germination of an idea into a realizable form of commercial value.
  • Entry vector (EV): the knowledge encapsulation of an assumption regarding the problem into a distinct path leading into the problem solving space.
  • Functional stream (FS): the detail, micro level structuring of the entry vector (EV).
  • Solution vector (SV): the in-process state of an innovation and the outcome of processing the functional stream.
  • Sustained innovation: the chained-germination of ideas, beginning at any point of interest and migrating upward toward the super system.
  • Efficient innovation: results from the maximal use of resources that are often freely and readily available and by the conversion of constraints into opportunities.

Introduction

Sustained innovation is analogous to a chain reaction. When initiated at any level within the system of interest it promotes the rapid generation of other innovative solutions within the system. Three aspects of sustained innovation are of interest in industrial and commercial settings:

  1. Large number of concepts generated
  2. The speed that is generated
  3. Unexpected outcomes that emerge from the exercise as a result of serendipity

This paper demonstrates a planning approach to assist with the systematic application of TRIZ for sustained innovation. The author begins building innovation momentum with the air safety issue of adhesive tape removal. This leads to solutions that originate around the artifact and are directed toward the super-system.

The new approach combines TRIZ thinking with systems engineering principles. Systems engineering is a team effort with a structured development process from concept to production to operation that ensures a customer’s needs are met through a system’s life cycle. It is essential for the structure and execution of projects with any degree of size or complexity.8 It does not provide built-in mechanisms for the rapid generation of new ideas and parallel (improved) concepts.

Systematic design and engineering is another essential area best exemplified by the work of German systems engineering experts Gerhard Pahl and Wolfgang Beitz where systematic approaches were used to achieve efficiencies in the field of engineering design.9

The Theory of Inventive Problem Solving has an extensive suite of idea generation tools which are deployed to suit any task.1 This flexibility transfers the responsibility for planning and structuring and its successful execution onto the user. The typical user is accustomed to precise, algorithmic approaches through years of formal educational training. The lack of structure is construed as a handicap- something outside the comfort zone.2

How to combine the diametrically opposed requirements of free association of ideas with algorithmic structuring is a debate that will continue for some time. Interesting new developments have been reported, including that of the BRIGHT process in the United Kingdom (UK).13 Hybrid-reasoning is a powerful and efficient approach in discursive problem solving and it is the approach used in the development of the SSA.

Perspective on Airline Safety Issue

The work on this paper was completed in approximately 2007 to prepare teaching material for a TRIZ workshop and was based on an airline safety issue dating back to 1996. While the original tape removal problem was solved by the airline industry through root cause analysis, recurrences (in March 2006, March 2009 and July 2009) indicate a need for further work in the general airspeed sensor area.

This paper introduces the new approach with more than 25 conceptual solutions. It is possible to develop solutions using TRIZ tools that users are familiar with. In a few instances the use of a specific TRIZ tool has been suggested as a hint. In TRIZ, as in any other creativity-based discipline, there is no single control route to arrive at a solution to a given problem.

Airliner Safety Issue Background

Aeroperu Flight 603

At 42 minutes past midnight, on October 2, 1996, Aeroperu Flight 603 with 70 passengers took off from Lima, Peru and headed for Santiago, Chile.3 The Boeing 757-23A (registration N52AW) was relatively new and in “perfect” condition. Soon after take-off the air data computer started feeding erroneous data to the flight computer and to the two sets of instruments for the captain and first officer. While one set indicated a condition of over-speeding, the other warned of a low speed stall; both conditions were dangerous. Altitudes displayed were widely different and seemingly contradictory alarms sounded randomly, often simultaneously.

Figure 1: Location of Pitot-static Probes on Boeing 757

Murray T C Douglas, Whenuapai Airshow 2009, Auckland, New Zealand

Figure 2: Wreckage Showing
Taped Ports of N52AW

The disorientation of the flight crew in the pitch black of night led to the declaration of an emergency; they elected to return to Lima. Under conditions of extreme stress, the captain was able to return within 40 miles of Lima at a steady height of 1600 feet by relying on the radar altimeter. Independent verification was sought from the Lima air traffic control radar, which acknowledged the plane’s position and confirmed its height at 8000 feet (ironically a value received from the aircraft’s erroneous transponder).

Reassured by the independent verification, the flight crew started the descent in darkness. Ignoring miscellaneous warnings and alarms (including ground proximity warnings), the plane struck the water. The left engine took on water and flamed out. The flight crew tried to recover by initiating a climb but as the right wing of the plane rose, the left wing dropped and its wingtip caught the waves. The aircraft cart wheeled and turned upside down at 1:16 a.m. Any initial survivors had perished by day break.

The entire chain of events was established by the recovery of the voice/data recorders and pieces of wreckage from a depth of 500 feet by the U.S. Navy.6 The left side static ports were found covered with adhesive tape used by the cleaning and polishing crew (Figure 2). The tape should have been removed prior to the flight to ensure that the ports were clear of any obstruction. This lapse had not been detected during the pre-flight inspection due to the metallic sheen and the height of the B757 above the ground. (The right side static ports panel were not be recovered from the sea.)

Birgenair Flight 301

An almost identical accident took place only seven months prior on February 6, 1996 when another Boeing 757-225 (registration TC-GEN), operated as a charter flight by Birgenair, crashed into the ocean at night soon after take-off.4

Birgenair Flight 301 took off at 11:42 p.m. from the Dominican Republic and headed for Newfoundland and then to Germany. The captain’s set of instruments displayed erroneous airspeed readings. The confusion on board was compounded by the autopilot, which, operating on erroneous data, automatically reduced engine thrust during the critical climb-out phase.

This caused the plane to slow down (almost to the point of entering a stall) when the wings stopped generating lift. As the aircraft descended in complete darkness toward the ocean below, the flight crew had no external horizon of reference. The instruments gave conflicting readings which were disregarded. By the time the captain disengaged the autopilot and increased engine thrust to recover manually, the aircraft was too low and hit water at 11:47 p.m. Of the 189 on board, none survived.

Figure 3: Birgenair Boeing 757-225 TC-GEN

Lutz Schonfeld, Wikimedia Commons. Google 3D Component Warehouse

The cause of the crash was attributed to a possible build-up of wasps’ nests inside the exposed pitot tubes. The chartered aircraft had been sitting unattended on the tarmac for several days prior to the flight.

Additional Air Safety Incidents

In 2008, the Sydney Morning Herald reported that between January and March 2006, five Qantas A330 Airbus flights had to abort take-off due to wasp-related blockages of the pitot-static system.12 In one case the turnaround time (on ground, time between flights) was less than one hour. Emergency braking during one of the aborted take-offs caused six of eight landing gear tires to burst on the runway.

On March 5, 2009 it was reported that the likely cause of the crash of Turkish Airlines Boeing 737-800 at Schiphol, Amsterdam was a faulty altimeter. This erroneously indicated ground level height while on approach caused the autopilot/flight computer to enter the post-landing phase, to automatically reduce engine thrust and likely deploy spoilers while the plane was still in the air. The aircraft stalled, dropped and broke up into three pieces approximately one kilometer from the runway. Of the 135 occupants, there were 50 injuries and nine deaths, including four of Boeing’s engineers.

On June 1, 2009 Air France Flight 447 crashed in the Atlantic on its way to Paris from Rio de Janeiro. All 228 died. An element of the cause: a problem with the pitot tubes.

Figure 4: The Pitot-static Schema

The pitot-static system is an established and reliable method of obtaining speed- and height-related information.7 The method is simple. A pitot tube, pointing in the direction of flight, gathers dynamic air pressure, which is fed to the airspeed indicator. Static ports, that reference non-dynamic (static) air pressure from the side of the aircraft, provide data on altitude. It is also used to compensate for the effect of altitude on airspeed data.

As long as the pitot and static ports are free of obstructions, the system works. Obstructions, however, are caused by icing external object ingestion and blocked ports will generate erroneous data which may be difficult to detect before problems occur.

Current Procedures for Airbus and Boeing Aircraft5

Figure 5: Boeing Recommended Current Practice

As a remedy to covering the static holes problem (issued in 1998) Boeing recommended that maintenance personnel should place one end of a three-foot piece of orange barricade tape over the static port and secure the orange barricade tape with yellow vinyl adhesive tape. In addition, a red paper tag that read “static ports covered” must be attached to the left control wheel in the flight deck. The remedy devised by Airbus is to have specially designed bright orange polymer covers placed over the ports, which are removed before flight. Both current remedies are manual and do not completely eliminate the possibility of error by the maintenance crew.

Introducing the SSA to Innovation Planning

The outcome of any innovation activity is almost entirely contingent upon the following five factors:

  1. How accurately the problem is defined and framed
  2. What assumptions are made at the inception
  3. What directions for investigation are adopted
  4. What knowledge base is initially available
  5. What additional resources can be used, in due course, to bridge the knowledge-gap

The accident descriptions given provide sufficient information to define the problem, form assumptions and decide on directions for investigation. In the SSA, what is known about the problem is encapsulated and transformed into distinct entry vectors (EVs) leading into the problem solving space. The proposed approach aims to further convert each EV into four functional streams for detailed analysis.

An important issue in the processing of EVs is the mandatory requirement to continually vary the field of interest (or depth-of-field) from the artifact toward the super-system. Start by forming EVs at any level of detail; the approach requires that EVs at the macro and the super-system level should also be considered.

This is an essential requirement as it provides the structuring for the innovation task at the macro level. The functional streams provide the structuring at the micro level.

An initial observation was that each aircraft was airworthy until the moment of impact. The anomaly, however, occurred in the flow and processing of information. No external act of nature forced a deviation from the normal flight path. Each aircraft was designed and equipped to cope with almost all conceivable flight conditions.

The flow of information generated and processed within the aircraft (i.e., internally within the system of interest) is the main area of investigation. The focus is on the following information-related sub-systems within the aircraft (Figure 6), beginning by forming the closed boundary of the system for an aircraft in normal flight.

Originating Source of Information: The Pitot-static Airspeed Measuring Circuit and Transducers

EV1: Susceptibility to blockage through ingestion or icing(a maintenance and design issue).

EV2: Improvements to reliability, fail-safe operation mode (a product improvement issue).

Information Interfaces: Flight Crew and Flight Instruments

EV3:Incomplete situational awareness (an information management issue).

EV4:The inefficient transfer of vital information (an ergonomics issue).

Processors of Information: The Flight Crew and Digital Flight Controllers

EV5:The inefficient processing of time-critical information (a training issue for the flight crew) (a systems design issue for the digital flight controllers).

EV6:A possible inverted pyramid syndrome where the latest technology has been added to and built upon an essentially unchanged and limited foundation. The advanced color screens of the glass cockpit may have impressive displays but have no mechanism to test or to improve upon the data provided by the older pitot-static system (a systems design issue).

Figure 6: Entry Vectors (EVs) into the Problem Space

The following is further analysis of entry vectors: EV1, EV2 and EV3 at the micro level to derive four functional streams from each of the EVs.

Functional Streams Derivation from Entry Vectors (EVs)

Functional streams may be likened to a dissected view of the problem’s EV as seen in a systems engineering context. Here, the interest is focused on a dynamic study of the EV, its sub-components and internal workings. This is done by varying the scope of review in four steps (of the same EV) to derive the corresponding four functional streams.

Each of the four functional streams represent a snapshot of the EV, differing only in the extent to which the sub-components of the EV can be modified, adapted or replaced (Figure 7).

To derive a functional stream from an EV, treat each EV as an intermediate system of interest. Then consider the external and internal interactions within the reference.

Interface [FS + 1]: This first functional stream is limited to interfacing issues involving a limited amount of innovative effort. Consider the narrow zone where force, material and information (interchange) occurs as an interface among the EV (considered a system of interest) and the other corresponding components with which it interacts. For instance, consider the physical hardware of the pitot-static device to form an intermediate system of interest. The interfacing on one end of this system is the ram air probes on the external surface of the aircraft where the data originates. The other interface of this system is the visual display of the processed data on the cockpit instruments.

Minor [FS + 2]: In this second functional stream, the zone of interest is expanded inward from the interface zone. The focus is on generating limited changes within the systems of interest that are localized internally and are often adjacent to the interface zone. The reason for using the term “minor” is that the scope of changes allowed is of a minor nature and is limited to a small portion of the constituents of the EV.

Figure 7: Functional Streams (FSs) and Generated Solution Vectors (SVs)

Major [FS + 3]: In the third functional stream, the zone of interest is expanded to cover the majority of the sub-components within the EV. The one exception is that some sub-components must be retained and cannot be modified or replaced for technology or legacy reasons. As the scope of this functional stream covers the majority of sub-components within the EV, it is referred to as such.

Evolutionary [FS + 4]: The fourth level functional stream is derived by focusing on the EV and by devising an evolutionary replacement for its constituents. For example, what if there is a change to the form of the material? The force and information flows within the EV. The transmission of information within the pitot-static circuit may be changed by replacing material flow of air pressure with the transmission from the originating source of electronic signals or electro-optical data. On the exterior of the aircraft it may still have some form of airspeed sensors but internally all else is replaced until it reaches the data processors and cockpit displays.

Paradigm change [FS + PC]: The fifth level functional stream requires different thinking. In order to escape the original defined boundaries of the system consider the task from the perspective of the super-system or its super-system looking inward at the original problem.

Generating Solution Vectors (SVs) from Functional Streams

Three of the six EVs (Figure 6) have been resolved into functional streams. At each level of the functional stream, an individual can generate SVs as shown in Table 1.

Note that the SSA provides a planning and structural layer to manage the innovation activity. The Theory of Inventive Problem Solving methodology is used to derive the solutions from the direction provided by the SSA in each instance.

It should also be noted that this solution set was generated for the Aeroperu taped static port problem. The solutions were not modified or adapted for the more recent incidents. Not every possible combination is listed in Table 1.

EV – 1 Eliminate Susceptibility to Blockage

FS + 1 (Change limited to system interface)

  • SV1: Directed light source located within static port.
  • SV2: Detect magnetic substrate of special covering tape.
  • SV3: Detect conductivity of special covering tape.

FS + 2 (Minor changes to system)

  • SV4: Detect presence of covering tape by acoustic sensor within port.
  • SV5: Detect presence of covering tape by ambient/reflected light sensor.
  • SV6: Detect presence of covering tape by air pressure release sensor.

EV – 2 Improvements to Reliability/Product Development

FS + 2 (Minor changes to system)

  • SV9: Use ram air (dynamic air pressure to increase engine power) with pebbled surface around port opening.
  • SV10: Use ram air with easy peel-off paint around port opening.
  • SV11: Use ram air with detachable skin panel around port opening.
  • SV12: Use ram air with heated skin panel around port opening.
  • SV13: Use air pressure pulse within port to clear obstruction.
  • SV14: Built-in swing away covers over port.
  • SV15: Built-in sliding metal skin panel over port.
  • SV16: Built-in retractable metal skin panel over port.
  • SV17: Special water repellent baffle (device that regulates flow) installed over port.

FS + 3 (Major changes to system)

  • SV18: Nose wheel landing gear door extension to block port when landing gear down.
  • SV19: Ultra high frequency (UHF) antenna on landing gear door to block port when landing gear down.
  • SV20: Relocate air pressure transducers to exterior surface of aircraft.

FS + 4 (Evolutionary change to system)

  • SV21: Use special polymer external panels to register dynamic air pressure.
  • SV22: Instrument external metal skin panels to register dynamic air pressure.
  • SV23: Use ionized air pulsing to measure airflow.
  • SV24: Use an array of ionized air sensors to measure three-dimensional airflow patterns.
  • SV25: Use ground mapping radar with digital terrain matching.
  • SV26: Use ground positioning satellite system at all altitudes.

Table 1: Solution Vectors (SVs) Generated for Entry Vectors (EVs) EV1, EV2 and EV3
EV – 1
Susceptibility to
blockage
EV – 2
Improvements to
reliability
EV – 3
Absence of critical information
EV – 4
Inefficient transfer of information
EV – 5
Rapid processing of information
EV – 6
Inverted pyramid syndrome
FS + 1
Interface

S1
S2
S3

S6

FS + 2
Minor

S4
S5
S6

S9
S10
S11
S12
S13

S7

FS + 3
Major

S18
S19
S20

FS + 4
Evolution

S21
S22
S23
S24
S25
S26

EV – 3 Incomplete Situational Awareness

FS + 1 (Change limited to system interface)

  • SV7: Flight computer does not allow engine start if tape auto-detected.

FS + 2 (Minor changes to system)

  • SV8: Flight computer does not allow engine start if special covers not removed and stowed into cover receptacles within landing gear doors.

Discussion of Generated Solution Vectors (SVs)

The following is a description of the solution vector (SV) process listed in Table 1.

SV1: Passive Assistance to Detection

This is a simple, passive SV to detect the presence of any obstruction or tape covering the static ports at night. A low intensity laser source located in the static port emits a beam that is directed downward, at an angle, at the tarmac. Ground personnel can detect the presence of a beam or its intensity, visually with a hand-held sensor even in complete darkness no matter the height of the above ground static ports. Any type of tape or material obstructing the ports can be detected (TRIZ standard solution 1.1.5).

Figure 8: Solution Vector/SV1

SV2, SV3: Auto-detection of Special Tapes

These are the active versions of SV1, where the static port is equipped with the means of checking the conductivity or magnetic substrate of the special covering tape. The sensors are located flush with the exterior surface of the aircraft, in the proximity of the static ports. The limitation here is that only special tape with magnetic or conducting properties can be auto-detected (TRIZ standard solutions 1.1.1, 2.4.1, 4.4.1, 5.5.1).

SV4, SV5: Auto-detection of All Types of Tapes

These SVs are the active version of SV1 for the detection of tape using the principle of reflected acoustic or light beam. The emitter and receiver are located within a fairing inside the static ports (TRIZ standard solutions 1.1.2, 1.1.4, 3.1.1).

SV6: Auto-detection by Low Pressure Air Pulse

This SV relies on monitoring decay of a low-pressure air pulse within the circuit. The main advantage is that by using solenoids to isolate the sensitive instrument transducers, this SV can check the entire path of the pitot-static circuit for blockages. The pitot and static sides are further isolated and checked separately (TRIZ standard solutions 1.1.4, 5.2.2).

SV9, SV10, SV11, SV12: Auto Removal of Tape During Flight

The detection of an obstruction is not as useful as the means of automatically removing such an obstruction during flight. In TRIZ the suggestion is to consider using freely available resources first and then try to achieve solutions where the desired result is achieved. To remove a tape covering the static port an individual can use ram air effect of the passing airstream. To break the adhesive bond, consider a pebbled stainless plate forming the exterior of the static port as in SV9. The use of easy peel off, low adhesion paint, as in SV10, could be another option; as would a releasable cover plate as in SV11. The application of additional energy is suggested in SV12 (TRIZ hint: smart little people).

SV13: Auto-removal of Obstructions by High Pressure Pulse

The four SVs address the issue of tape removal of the static port, which is a somewhat unlikely occurrence. What is more probable is the partial obstruction of the circuit due to foreign object ingestion, wasp activity, etc. In order to detect blockages for SV6 an air pressure pulse is used. In SV13 it is intensified by using a high pressure pulse for clearance of internal or taped over obstructions. The outstanding advantages of this include:

  1. Detection, clearance and verification done automatically by the same SV.
  2. There is no need to modify the pitot tube or static port geometry at the exterior or interface level.
  3. The concept is well-suited to retro-fit into existing systems.
  4. A preventive purge cycle may become routine as the aircraft leaves the apron and taxies to the runway.

SV14, SV15, SV16: Retractable Covers

This set of SVs emerges from the problem space with a view to automate the placement and removal of covers on the static ports using TRIZ philosophy first use available resources (SV14 and SV15) to rely on airflow to actuate the covers. A simple, spring-loaded mechanism keeps the ports covered until the force of the airflow is sufficient to move the covers. For SV14 it suggests a sliding arrangement, while SV15 is based on a rotating/pivoting arrangement. The method of operation uses a free resource, the airflow past the static ports. The aerofoil converts the energy of the airstream into an opening torque. The cover can be locked in open and closed positions. A limitation of this SV is that it will not deploy at low speeds as the aircraft is taxiing. This is not critical as other more precise methods are available during take-off.

Figure 9: Self-actuated Static Port Cover

SV16: Pivoting Cover Arrangement

This SV provides a pivoting cover arrangement with an independent actuator that is deployed upon engine start.

SV17: Ingestion Resistant Covers

Within this direction a number of SVs can be generated- all designed to reduce foreign object ingestion and allow relatively free passage to air. Any such modification at the entry and exit to the pitot-static circuit will require recalibration of the data, which in digital form is much easier than in the older analog versions. Possibilities within this SV include water repellent baffle covers over the static port, wire-gauze netting covers, thin criss-crossing wires with high-voltage capacitative charge, etc. (TRIZ tool: smart little people).

Figure 10: Self-actuated Static Port Cover Closed (SV15)

Figure 11: Self-actuated Static Port Cover (SV14, SV15)

SV18, SV19: Relocation of Static Ports Near Landing Gear Doors

This series of SVs are the result of using the FS + 3 (functional stream), which mandates a major change to the existing system. The internal tubing of the pitot-static circuit and location of the transducers has to be re-routed inside the front of the aircraft. The advantage of this SV (from the TRIZ viewpoint) is the existing resources are used to perform additional functions. Also, in compliance with axiomatic design principles, it is gaining a third functionality from two entirely unrelated elements without suffering functional interference at any point.10,11 The ventral UHF antennas are not used while on the ground as the dorsal antennas are better positioned. During this period use the antenna as a cover. Once the aircraft is airborne, the landing gear doors close over the retracted landing gear, the UHF antenna begins its original task and the static port cover materially disappears. A physical contradiction is resolved on the change of condition, as per TRIZ thinking (TRIZ tool: physical contradiction, the cover must be present on ground and must materially disappear once airborne).

Figure 12: Repositioning UHF Antenna on Landing Gear Door

Figure 13: UHF Antenna as Static Port Cover (SV19)

SV20: Eliminate Tubing from the Pitot-static Circuit

This is also an example of the FS + 3 (functional stream). The major change is a modified form of transducers that are relocated to the exterior of the aircraft. The objective is to directly obtain air pressure and dynamic air pressure data from the ambient airflow. The pitot tubes, static ports and all internal tubing can be dispensed and are removed. From a TRIZ viewpoint, this is a superior SV since the problems of tubing blockage are also eliminated with the tubing (TRIZ hint: functional trimming).

SV21 through SV26 are all examples of the fourth functional stream, FS + 4 where evolutionary change is considered to encompass the entire system in question. The goal is to develop SVs that will provide the desired functionality by completely replacing present technology. From an innovation perspective, these are SVs of a higher order. The only SVs superior are those originating from the fifth FS + PC (functional stream paradigm change) where evolutionary change is propagated to the super-system and is deployed from a higher, unknown, vista. The outcome of the FS + PC will span and possibly eliminate several components within the encompassing super-system.

SV21, SV22: Dynamic Pressure Sensing

This SV applies TRIZ principles to SV20 to reduce extraneous components by trimming and by merging desired properties within structural components. Special polymer panels are mounted flush with the exterior skin to register dynamic air pressure for SV21. The polymer panel can act as a diaphragm to convert air pressure directly into data or through the intermediary of a fluid membrane cell. The metal skin panels are fitted with strain gauges to convert deflection under air pressure into a pressure reading for SV22. In this SV, a segment of the external aluminum alloy skin of the aircraft is instrumented to provide deflection data under the dynamic air pressure. This relationship is linear throughout all conceivable flight parameters. Using simple neural networks, self-calibration of data would be possible. Also, SV22 provides the possibility of measuring static pressure with a sealed, double-walled skin panel.

The benefit of SV22 lies in the fact that the skin panels are made to perform two entirely separate and unrelated tasks, simultaneously, without functional interference. In this manner, SV22 maintains the independence of functional requirements and also decouples the functional elements. In this, the SV meets the first principle of axiomatic design.

These series of SVs also remove the need for pitot probes, static ports and associated internal tubing of the circuit. The original basis for launching the innovation exercise has been eliminated by using functional streams as it begins to migrate toward SVs for the super-system.

SV23, SV24: Using Scientific Effects

This set of SVs suggests using known scientific evidence and effects to measure airflow. The idea is to develop a solution based on solid-state qualities such as:

  1. Extremely rugged, reliable and contamination resistant
  2. Unaffected by moisture or rain
  3. At the early stages of a new technology S-curve

A transformation from an existing technology toward a new technology falls in line with the TRIZ methodology. One of the markers for a change-over is when the existing technology base is unable to cope with rapidly growing demands that are placed on it. Pitot-static systems were around in the 1930s (if not earlier). The performance requirements of the new digital flight systems have evolved rapidly so that a technology switch-over is indicated.

Figure 14: Three-dimension Airflow Sensors Based on Physical Effects (SV24)

There are known techniques to measure airflow such as small turbines and hot-wire anemometers. A new method of detecting a ping or pulse some distance downstream needs to be developed. In SV23, the emitted /antenna is located at the nose of the aircraft while the receivers are located aft. Depending on the speed of the aircraft, the time for a pulse of ionized air will vary and can be measured. Laser interferometer systems may be adapted for this purpose. The SV provides the direction to proceed in. It will require a substantial amount of research and development before a workable solution emerges (TRIZ hint: database of physical phenomena and effects, trends of evolution of technical systems).

SV24: Three-dimensional Flow Patterns

SV24 suggests using an array of emitters and sensors to obtain three-dimensional flow patterns about the aircraft. Thus, components of roll, pitch, yaw, drift and angle of attack may be obtained differentially from the data (Figure 14).

The following two SVs propose extending the use of navigation technologies developed for defense purposes toward civil aviation.

SV25: Ground Mapping Radar with Terrain Following

Most military aircraft use ground mapping radar as a means of high-speed navigation at low levels. Versions suited to civil aviation can provide additional situational awareness to the flight crew to support standard navigational aids. Airline disasters have resulted from confusion in the cockpit caused by poor ground communications, bad weather, pilot fatigue, failure of ground navigation aids and more. Terrain following can provide a three-dimensional reference to the aircraft’s position vis-à-vis its environment, especially in mountainous regions during landing. Ground mapping is of little use over large bodies of water except for altitude indication (TRIZ standard solutions 3.1.1, 3.1.4).

SV26: Global Positioning System (GPS) Monitoring of Aircraft Position and Altitude

Global positioning system technology is commonplace and continues to evolve at a fast pace. This is a key resource, widely available at a non-prohibitive cost. As TRIZ recommends, consider all resources when coming up with innovative ideas for the task in question.

Until the year 2000, a policy of selective availability meant that high-end GPS devices were reserved for U.S. military use while civilian applications were provided a degraded signal with resolutions of 100m. After a change of policy all GPS devices and specifically the global navigation satellite system (GNSS) have resolutions of 10m-20m or better. Differential or augmented systems have resolutions of 1m-2m. Specialized systems, such as one used for agricultural use, combine a GNSS and ground based wireless navigation signals with a resolution approaching 0.01m.

With newer GPS devices planned such as the European Galileo, the Russian GLONASS, the Chinese Beidou and the next generation Garmin GPS 4-Pin USA, an individual can expect signals of much better resolution. Local augmentation of the signal by land based stations and/or by dedicated regional satellites will further improve the resolution.

Figure 15: Augmented GNSS Aircraft Position, Velocity and Altitude Data (SV26)

SV26: Improving Flight Safety

This SV proposes an arrangement of four receiving stations on the aircraft as shown in Figure 15. This would provide not only position, altitude and velocity information but also the roll, pitch and yaw components of the aircraft’s altitude. The goal is to improve flight safety and to fly continually optimized profiles with dynamic updates based on weather conditions as to conserve flight time and fuel consumption. Here SV26 approaches the fifth functional stream level of the paradigm change (TRIZ standard solutions: 3.1.1, 3.1.4 transition to bi-, poly-system).

The following two SVs follow EV3, incomplete situational awareness and providing feedback to the flight crew prior to take-off.

SV7: No Engine Start if Port Obstruction Auto-detected

The EV3 is directed at improving situational awareness in the cockpit. The ideal final result (IFR) is to not have a problem in the first place. Solution vectors SV2, SV3, SV4, SV5 and SV6 deal with the auto-detection of a blocked condition. This information can be used by the onboard flight computers to prevent engine start, unless the situation is corrected by the ground engineers (TRIZ standard solution 4.1.1 self-regulating system, no need for measurement).

Figure 16: Static Port Cover Stowage for Landing Gear Door (SV8)

SV8: Engine Start Only on Proper Cover Stowage

This SV is also based on EV3; however, it employs an entirely different approach. Airbus airliners come equipped with dedicated port covers. There is a slight chance that these covers may be inadvertently left on at night or in poor light/weather. The stowage space proposed within the front landing gear door can be wired to indicate that a cover has been properly secured and is no longer on the ports. The engine start sequence can then be activated (Figure 16).

There remains the possibility that the ground crew may have a number of spare covers, which they could use for a work-around as a pit crew to minimize on ground turn-around time. If the original cover were left on at night, the original problem returns.

By tagging each cover with a radio frequency identification device (RFID) chip and having a sensor built into the receptacle space, SV8 ensures that the possibility of error or mischief is greatly reduced. The covers cannot be switched or swapped, they travel with the aircraft and the SV8 requires no modification of the pitot-static circuit, its components or its interfaces.

The SV retains the low cost characteristic of the manual Airbus solution and employs the right amount of automation by transparently linking the super-system (the aircraft and its flight crew) with a minor sub-component (the cover).

Figure 17: Problem Space, Entry Vectors (EVs) and Functional Streams (FSs)

Advantages of the Super Stream Approach (SSA)

As a Process Structuring Tool

The SSA provides a structuring exoskeleton to the innovation effort. An individual can select the EVs to establish the program’s course. The choice of the EVs determines the immediate, the intermediate and long-term expectations from the exercise. For each of the EVs it is known that at least four functional streams will have to be developed. As shown in Figure 17, EVs are the vehicle for innovation planning at the macro level. Functional streams perform the primary task of innovation in the small; at the micro, detailed level.

For Assumption Modeling

Entry vectors provide an explicit and unambiguous record of the assumptions formed at the start of the innovation program as well as during its execution.

As a Momentum Building and Directing Tool

Establishing momentum early in the innovation exercise and feeding it off early successes is crucial.2 It is also vital to give the right direction to this momentum. There is little purpose in expending valuable resources for developing concepts that will be bypassed or made redundant by others. For example: SVs 1-5 and 9-12 can be bypassed by gains in: SVs 21-24, which can be bypassed by advances in: SVs 25 and 26.

It stands to reason that SV25 and SV26 should be given the highest priority, unless there are valid reasons: technological, policy or other, for delay. In this case, the momentum should be reversed from this point and redirected toward the middle tier.

For Large/Small Innovation

This is an important concept which needs elaboration. Innovation in the small is the isolation of focus and its concentration on an artifact, a product or a process. Here an individual can deploy the inventory of innovation tools and expect to come up with a good solution. It may need to be drilled down from the system level to the sub-system level to the component and function level and finally the parameter level. This may need to be repeated until a satisfactory outcome is reached.

An exceptional solution may approach the IFR in delivering the desired outcome at minimal cost.

The concept of innovation in the large is different. The goal is to generate more than one SV (minimum of four SVs in a set). Of these, the SVs rank based on the following criteria:

  1. Number of SVs in the set that will be made redundant by this SV.
  2. Position of the SV on the technology S-curve. To introduce a new technology curve or to be placed at the early stages of an existing curve is preferable.
  3. Other issues such as developmental costs, environmental issues, government policy, international collaborations, etc. can enter at this stage when evaluating the entire SV set. These issues are not considered earlier.

Some may agree that achieving an IFR on a SV that will be supplanted at the innovation in the large stage is not an ideal outcome. This can be seen in SV19 and SV22, where both approach a high IFR when compared to SV26.

For Dynamic Evaluation and Serendipity

Functional streams encourage the generation of multiple solutions, which may be in varying degrees of completeness at any given point in time. A mature innovation program in an organization is one that has several projects completed or in the pipeline. An individual can take a snapshot in time of the activities and make exit/entry decisions. Additionally, the visibility of multiple SVs encourages aspects of serendipity through further ideation and merging.

For Enrichment of Innovation Vocabulary

An individual also does not possess a precise vocabulary to classify aspects of innovation – a generic term that is freely and interchangeably used to describe the mindset, the capability, the process, its outcome and the reasoning involved.

The SSA presents the EV as a composite of the assumptions with the prior knowledge about the problem space. The SV is the output of the innovation exercise and is the in-process form of an innovation, something between the idea and the commercialized form of the innovation. Solution vectors form the in-process inventory of the innovative organization and can be in different states of completeness and readiness for commercial gain.

Conclusion

This paper proposes the super stream approach augmentation (SSA) as a planning and structuring layer to enhance the application of TRIZ tools for sustained innovation. The application of the SSA is demonstrated in an ongoing issue in airline safety where several unique innovative concepts have been generated. This subject was selected for the relatively free access to related information on the Web.

The approach assists in setting out the initial assumptions for the innovation effort to proceed along multiple paths, serially or preferably in parallel. By imposing the requirement for functional streams each path is resolved further into four paths for detailed analysis. Thus, a network of solutions and various levels is derived.

The advantages of this approach for sustained innovation are highlighted by the fact that it was based on information beginning in 1996 through the view of the Air France Flight 447 disaster of June 2009.

Directions for Further Research

Any new development that complements, supplants or bypasses the proposed methodology would be a desirable addition to the larger field of innovation sciences.

Also, in developing an enhanced vocabulary of innovation terms an individual needs granularity to bring the various components and stages of the innovation process into sharper focus. The limited vocabulary in the field of innovation causes key aspects to become indistinguishable in a diffused haze. Developed bodies of science must have, out of necessity, sophisticated vocabularies.

References

  1. Ahmed, S. S., “Analysis Management: TRIZ and Systematic Innovation- An Overview,” The TRIZ Journal, March 2005.
  2. Ahmed, S. S., “Rapid Innovation with TRIZ, Part 1,” The TRIZ Journal. June 2005.
  3. ASN Aircraft Accident Boeing 757-23A N52AW. Lima, Peru. October 1996. (Aviation Safety Network)
  4. ASN Aircraft Accident Boeing 757-225 TC-GEN. Puerto Plata. February 1996. (Aviation Safety Network)
  5. Boeing Aero Magazine (Boeing Aero Magazine Aero4, Boeing Commercial Airplane Company, Seattle WA, 1998)
  6. Cockpit Voice Recorder (Cockpit Voice Recorder Database)
  7. FAA Pilot’s Handbook (Aviation/Pilot Handbook)
  8. INCOSE Systems Engineering Handbook, INCOSE Central Office. Seattle WA, 2002.
  9. Pahl, G. and Beitz W., “Engineering Design- A Systematic Approach,” 3e, Springer, 2007.
  10. Savransky S. D., “Engineering of Creativity,” CRC Press, Boca Raton, FL, 2000.
  11. Suh, N. P., “The Principles of Design,” Oxford University Press, USA, 1990.
  12. The Sydney Morning Herald. February 2008.
  13. Tsai, Shuo-kai and Childs, P. R. N., “TRIZ: Incorporating the BRIGHT Process in Design,” The TRIZ Journal. January 2009.

An earlier version of this paper was published on The TRIZ Home Page in Japan.