By Shree Phadnis

Abstract

The Algorithm for Inventive Problem Solving (ARIZ) is an excellent tool to solve problems once an individual has identified the mini problems that need to be solved. In real life situations, however, the problems are seldom clearly defined and there can be several problems and contradictions to solve in the initial situation.

Introduction

From an updated matrix of contradictions to semantic analysis, subcategories of inventive principles and a list of scientific effects, some interactive applications have attempted to simplify the problem formulation phase as well as the transition from a generic problem to a whole set of specific solutions.

Inventive problem solving with the algorithm (ARIZ) shows how and when to apply the tools of The Theory of Inventive Problem Solving (TRIZ). It is made up of several step-by-step procedures to solve complicated problems when other TRIZ tools will not work.

How to Identify Key Methods

There have been various methods based on functional analysis and root call analysis (RCA) that help identify the key problems for applying ARIZ. In order to increase the efficiency of this process the author proposes the following methods:

1. Understand the problem situation using the system operator approach and keep formulating problems.
2. Next, list all the identified problem statements.
3. Group appropriate statements, get rid of repeats and list a hierarchy of problems.
4. Then list all the statements in an X axis and Y axis (make a two dimensional matrix).
5. Evaluate each row. Use statements with the corresponding interaction and ask questions. If the problem is solvable does it eliminate the need to solve the problem completely, partially or should there be no action?
6. Create a tally sheet based on the two-dimensional matrix.
7. Identify the top problems that completely eliminate the other problems or generate partial solutions.
8. Put the identified problems in the form of a “cause and effect” diagram.
9. Identify the mini problems to be solved.
10. Apply ARIZ to solve the problems.

The Electric Windmill

Consider the following problem (generated with a TRIZ software product):

An offshore electric windmill is installed in a sea near the coastline and converts wind energy into mechanical energy produced by the rotation of the blades, which is subsequently converted into electricity. Due to strong winds, however, the velocity of the blade tips is high. This causes the upper part of the blades (or tips) to hit the dust particles and water droplets (which are present in high force air). As a result, the surface of the tips become deformed reducing the overall performance of the windmill. The blades should be periodically replaced, however, it is a costly procedure.

Supersystems and Sub-systems

For the system dimension answer the following questions:

1. What is the “system?” Answer: The system in this case is the blades.
2. What primary function does the system perform? Answer: The blades transfer energy from the wind to the hub.
3. What problem are needing to be solved? Answers: The problem of erosion due to impact of air particles. The problem of erosion due to impact of water particles. The problem of high impact due to strong winds.

Overall:

• Find a way to solve the erosion due to dust particles.
• Find a way to solve erosion due to water particles.
• Find a way to solve erosion due to strong winds.

1. What changes in the system might improve the solution?
2. Is it possible to improve the system to the extent that the drawback becomes insignificant or at least tolerable?

If the blades are made of some material that is erosion resistant the problem can be solved. For example, if there is some coating on the blades the erosion problem can be solved. If the blades can be easily mounted or removed then there are no maintenance problems.

• Find the right material that makes the blades erosion resistant and does not cost too much.
• Find a coating that makes the blades erosion resistant.
• Find a way to make the blades easily dismountable for maintenance.
• Find a way to make the blades cheap so that changing them is not expensive.

1. Is there another system (or alternate system) that can be improved in order to obtain the desired result?
2. Would shifting to some other principle of operation prevent drawbacks from occurring?
3. Would it significantly reduce or weaken it?

Use alternate systems that are erosion resistant, for example, rockets, hydrofoils or turbine blades. The coating of ice on hydrofoils is an extremely flexible material that absorbs the erosion.

• Find a way to form an ice layer on the blades to coat them.
• Find a way to make the blades flexible.

1. What is the anti-system and what problems were faced by the anti-system?
2. How did they get resolved?
3. Can some of those principles be used?

Methods that cause erosion, for example, shot blasting and sand blasting use systems to avoid erosion like a special coating with carbide.

• Find a way to coat with carbide.

Have similar problems occurred previously in other systems or other places? If yes, then:

1. How were they addressed?
2. By changing geometry?

• Find a way to obtain appropriate geometry that will help solve the problem of erosion.

Ask:

1. How come the earlier solutions do not work now?
2. Is it possible to modify a solution to make it useful for the situation?

For the supersystem dimensions answer the following:

• Describe the supersystem that the system belongs to. Consider other parts of the supersystem. For example, the hub, the alternator, the tower, the wind flow, the atmosphere, the electric wires, the generated power. Locate other systems near the supersystem or those that might be located nearby such as sand.

Other systems interacting with the system and its supersystem, especially sources of people, information, energy, etc. The maintenance people, the electrical energy, the solar energy, the wind energy.

• Consider conditions around the system and its supersystem (both artificial and natural) such as social and psychological environment, indoor and outdoor conditions.
• Requirements for interaction between the system and supersystem and the previously mentioned environment.

What elements from the environment might eliminate the problem altogether or at least reduce its severity?

• Find a way to use electric power to repulse the sand / water to avoid erosion.
• Find a way to reduce erosion despite the high velocity of the blades.

From what other supersystem (alternate or anti) can the desired result be obtained? The anti-system will contain a source for air such as the compressor.

• Find a way to obtain compressed air to repulse erosion.

For the sub-system dimension answer the following:

• Describe the structure of the system in its static state (when not operating). Indicate all sub-systems, important elements and connections. If necessary, develop a separate sketch or layout of the system in detail.
• Regard the structure of the system or anti-system. Use an alternate system as a resource for problem solving. How can modifying the system structure influence the problem? Perhaps some structural changes can eliminate the problem altogether or at least reduce its severity?
• Describe the functioning of the system in its dynamic state. List the functions for each of the sub-systems and describe the connections.

Functional Modeling

Use functional modeling to help reveal the set of problems to solve (for example, there is not enough information about the system).

For the dimension of inputs answer the following:

1. What enters the system (such as substances, energy, information)? Describe all inputs to the system. Possibilities include wind, force of wind, geometry of the blades, geometry of the blade tips, the material of the blades.
2. How does the input become an output?

The mechanical energy of the rotation is converted to electrical energy. First the linear kinetic energy of the wind is converted to rotational kinetic energy of the blades, which rotates the hub, which (by means of the magnets and windings of the generator) transforms rotational kinetic energy to electrical energy.

 

1. How can the input be changed to improve the situation?

• Find a way to modify the geometry of the blade tips.
• Find a way to use the correct material for the blades.

For this dimension answer the following:

• What outputs are created by the system? Electrical energy?
• Describe all the outputs and consider them as resources.
• How can an output be influenced to improve the situation?

For the dimension of causes answer the following:

• What is the cause of the problem?
• How is the cause transformed into the effect?
• Describe all known causes and critical conditions of the problem. What changes would eliminate the causes?

 

Figure 1: Blade Damage Diagram

 

• Find a way to eliminate the high speed of the wind in order to avoid the high speed of the blades.
• Find a way to eliminate the high speed of the blade tips.
• Find a way to eliminate improper geometry of the tips.
• Find a way to eliminate improper material of the tips.
• Find a way to eliminate or lessen the thickness of the tips.
• Find a way to eliminate sand particles that hit the blades.
• Find a way to eliminate sand near coasts.
• Find a way to eliminate the sand in air.
• Find a way to eliminate the high wind force.
• Find a way to eliminate water droplets in the air.
• Find a way to eliminate the high humidity.

For the dimension of effects answer the following:

1. Describe all known mechanisms regarding the cause of the problem using “cause-and-effect” chains.
2. What will be the consequences if this situation is not improved? Is there frequent down time leading to losses?
3. Is there another way to avoid these consequences?
4. How can the effect be influenced?

• Find a time saving solution with low maintenance costs.

For the dimension of time answer the following:

1. How long ago did the situation emerge?
2. Was this emergence associated with a specific event such as a change to the system, technology, strategy or environment?
3. Is it possible to “go back” to this event and change the outcome?
4. What events happened before the process?
5. How can critical events be changed?
6. Describe all previous attempts to solve the problem and explain why they did not work.
7. Can a future solution be implemented?

• Or was no new statement generated?

For the dimension of post time answer the following:

1. What is the after process of the system?
2. Describe the post process time intervals. How can an individual utilize the post process?

• Or was no new statement generated?

Now consolidate all the statements generated:

• Find a way to solve erosion due to dust particles.
• Find a way to solve erosion due to water particles.
• Find a way to solve erosion due to strong winds.
• Find a correct material that makes the blades erosion resistant and does not cost too much.
• Find a coating that makes the blades erosion resistant.
• Find a way to make the blades easily dismountable for maintenance.
• Find a way to make the blades cheap so that changing them is not expensive.
• Find a way to form an ice layer on the blades to coat them.
• Find a way to make the blades flexible.
• Find a way to coat with carbide.
• Find a way to obtain appropriate geometry that will help solve the erosion.
• Find a way to use electric power to repulse the sand / water to avoid erosion.
• Find a way to reduce erosion despite the high velocity of blades.
• Find a way to obtain compressed air to repulse erosion.
• Find a way to modify the geometry of the blade tips.
• Find a way to use correct materials on the blades.
• Find a way to eliminate the high speed of the wind in order to avoid the high speed of the blades.
• Find a way to eliminate the high speed of the blade tips.
• Find a way to eliminate improper geometry of the tips.
• Find a way to eliminate improper material of the tips.
• Find a way to eliminate or lessen the thickness of the tips.
• Find a way to eliminate sand particles that hit the blades.
• Find a way to eliminate sand near coasts.
• Find a way to eliminate sand in the air.
• Find a way to eliminate the high wind force.
• Find a way to eliminate water droplets in the air.
• Find a way to eliminate high humidity.

Create a Matrix

After this step collect the various methods listed and arrange them into a two-dimensional matrix for evaluation. For each row ask the question: If this problem is completely solved then in the interaction column is there a need to solve the interacting problem? If that interaction problem is completely eliminated list as E, if it is partially eliminated list as PE, if it is not eliminated mark as N. Add them up and focus only on the top E and PE problems shown in Figure 2.

 

Figure 2: Two-dimensional Matrix Evaluation

 

Next, represent the identified prioritized elements shown in Figure 3.

 

Figure 3: Prioritizing the Elements

 

Based on Figure 3 the problem statements to solve in order of priority are:

• Find a method of repulsing water and sand.
• Find the right geometry and flexibility.
• Find a method to reduce the blade speed.

Conclusion

Based on those statements an individual can create mini problem statements for each direction. There can be one or several mini problems that need to be solved with ARIZ. The author hopes that students of ARIZ will find this method useful for formulating the exact problem that needs to be solved to resolve difficult, complex situations.