After we or someone else have already solved the problem and got some ideas improving the parameter selected, the following situation can occur. The value of a selected parameter has improved but one or more of its other parameters deteriorate unacceptably. It is necessary to prevent deterioration of the parameters, to keep the values of both parameters at an acceptable level. A situation of the technical contradiction occurs.
It should be noted that the conflicting requirements in this case are expressed throughout the system, and the parameters in question can refer to absolutely different components within the system.
Method of developing the Swing technical contradiction
Stating a problem using a technical contradiction can be illustrated as kind of a “swing” – when one parameter improves, another one deteriorates – and vice versa. In this model, all the variety of information contained in the problem statement reduces to a confrontation between two parameters of the system. This simulation of the problem statement enables to understand the very essence of the problem well. However, the most important thing is that an effective tool – inventive principles – can be used to resolve the technical contradiction.
The technical contradiction can be formulated when stating the problem, at the stage of putting forward hypotheses. This happens when there is an opportunity to formulate the idea of the problem solution but this idea is not absolutely satisfactory. Similarly, a technical-contradiction situation can occur upon performing any actions to solve the problem. When we work with any problem models, ideas of a solution occur, i.e. it is a question of improving a certain parameter or process of the system. If the solution is satisfactory, everything is fine. If the solution cannot be considered satisfactory, then it means that another parameter has deteriorated, and its value is no longer satisfactory.
To develop a technical contradiction, it is necessary to clearly determine which parameter we have improved in one way or another. Then, to determine the parameter of the useful system which deteriorates during implementation of the method suggested. The problem model containing a technical contradiction (it is also called a two-parameter one) differs by a short statement of the problem. The technical contradiction is clearly stated here:
Improving parameter A of the technical system results in deterioration of its parameter B. How can this contradiction be resolved?
Examples of a technical contradiction:
Improving the Process Speed parameter deteriorates the Production Accuracy parameter.
Improving the Performance parameter deteriorates the Repair Convenience parameter.
It should be taken into account that not a single parameter can deteriorate, the deterioration can be complex, several parameters can participate in it. In this case, it makes sense to develop several contradictions – for each deteriorating parameter of the system.
Example. Vehicle
To increase the vehicle speed, the air resistance can be reduced. To do this, an attempt is made to make the vehicle as streamlined as possible and to press it down to the road. However, it is inconvenient to ride in a streamlined vehicle, from the point of view of convenience, the vehicle should resemble a brick by its shape.
The following contradiction arises: Improving the Vehicle Streamlining parameter results in deterioration of the Usability parameter.
Example of the contradiction between the Vehicle Streamlining and the Usability.
Altshuller's table to select TC resolution principles
The basis of the contradictions resolution table is the opposition of two parameters.
From the top down, parameters to be improved are listed. From the left to the right, parameters which can deteriorate are listed. In the cell at the intersection, the numbers of the principles most probably resolving the contradiction are provided. At the same time, the principles recommended in the first place are provided first.
Vehicles of various classes, from various fields of engineering are characterised by various parameters. Thousands and thousands of such parameters can be listed. This variety is a serious obstacle to developing a convenient algorithm for selecting a suitable inventive principle for the contradiction formulated. The totality of unique parameters of various devices is reduced to 39 typical ones each of which characterises certain features of extensive classes of systems. Pairs of parameters provide over 1,500 statements of technical contradictions.
How can a suitable parameter be found in the table?
It is easy if a particular parameter is almost or completely identical to the regular table parameter. For example, it is necessary to reduce the mass of a component. The table has the Mass parameter, we select it to develop a contradiction.
However, it is often difficult to find a particular parameter among the 39 parameters. In this case, it is necessary to understand which operational parameter from Altshuller's table affects this particular parameter: e.g., performance, repair convenience, strength, energy costs etc.
If you have doubts about selecting one parameter, several options of parameters can be considered. This will extend the list of recommended principles and, as a result, the variability of solutions.
Example. Selecting the deteriorating parameter when cleaning the heat-chamber tube
A sediment accumulates inside the tube feeding the solution into the heat chamber. This slows down the process and reduces performance.
To improve performance (parameter 39), you can open the chamber frequently, remove the tube, and clean it. However, these manipulations result in the chamber heat loss. The list of the table parameters has no “heat loss”. Still, it is easy to guess that heat is a type of energy. Accordingly, we select parameter 22 Energy Loss.
Alternative method to develop a model
Another method of working with the Technical Contradiction model involves formulating a contradiction in the implicit form.
The technical contradiction is that when a parameter of the system improves, another parameter deteriorates unacceptably. Understanding this, it is possible to concentrate on improving the parameter deteriorated keeping the parameter we have already improved when developing the technical contradiction at the necessary level.
To that end, it is necessary to understand which part of the system is related to the existence of the parameter deteriorated and to focus on improving that part of the system. In this case, it is the question of better adjustment of the system components and structure as well as of the system itself
with the operation conditions and the supersystem.
It is necessary to attribute the situation to one of the following:
1. The system requires improving the performance quality of the existing functions or introducing new functions. It is not adjusted by functionality.
2. The system is more complex, and the cost of its production and operation is too high. The system is not adjusted by cost.
3. The system is adjusted by functionality and cost but the system attributes are not adjusted – the geometric shape, surface or internal-structure condition.
4. Insufficient dynamism of the system. What is meant is the possibility of both mechanical mobility of the system parts and changes of the parameters of its components in general.
5. The structure and attributes of the system are adjusted but the system is poorly controlled. It means that operational adjustment is insufficient.
Upon selecting the appropriate case, it is possible to use the principles of resolving technical contradictions using the «System Transformation Operator.».
Work with the TRIZ Trainer
At the input of this step, we have an idea of the solution improving a parameter of the system. At the output, there is a technical contradiction formulated, i.e. we should understand which parameter deteriorates unacceptably upon putting forward the solution idea.
If Altshuller’s table is used, it is necessary to adjust the contradictory system parameters to the standard table parameters.
If the plan is to use the system transformation operator, it is necessary to state which disadvantage exists in relation to the part of the system responsible for the deteriorating parameter.
Running example. Pizza box
Tabular method of formulating a technical contradiction: It looks like the pizza would not stick to the bottom of the box but making the “pizza in the box” will become more complex. It means that a technical contradiction arises: Improving the Pizza Integrity parameter results in unacceptable deterioration of the Packing Production Complexity parameter.
The standard table parameters correspond to these parameters:
Improved: “Object composition stability”
Deteriorated: “Device complexity”
Implicit contradiction: We have a second case, unsatisfactory complexity, and the system cost.
