Trends of evolution is another powerful technique in TRIZ. Trends are used to predict the future characteristics of the products in the process of product evolution.

This concept is based on the fact that all products, process or technical systems eveolve over time. They go through an evolution from infancy through old age. Evolution is desirable as higher evolution means better product. The analysis says there are certain patterns of evolution which repeats in every product or system. TRIZ claims that if we can apply these trends or patterns properly we can predict the future stages of a product or system.

The number of patterns in the evolution are not fixed or decided, they are still under development by different TRIZ researchers. You may add a couple of patters for your purpose as suitable, but the underlying concept is the same. The patterns are derieved from the life cycles of the products. The life cycles are represented by s-curves. The four main stages of S-curve are infancy, rapid growth, maturity and old age.

Thus, not only the Inventive Principles are used repeatedly, but the patterns of evolution are also used repeatedly. This means, we can apply these patterns or trends (generic) on any product (specific) to predict the future inventions. In another sense, this can be applied on any patent application to expand on the claims and improve on the invention.

From another angle, the trends are based on the ideality. All products are moving towards their ideality. If we can think of the features of the ideal product, all stages between the current features and the ideal features are stages of evolution.

There are 8 laws governing system evolution. They fall into three categories, viz, Static, Dynamic and Cinematic.
Static Laws:
1. Completeness of parts of the engineering system. Every technical system consists of engine, transmission, limbs and controls. Evolution will take place to all these parts.
2. Enery Conductivity of the system- The better the transfer of energy inside the system, the better the system.
3. Harmony of the parts of the system- Better harmony in timing, frequency etc. improves performance of the system.
Dynamic Laws:
4. Transition from Microlevel to Macrolevel which improves miniaturization.
5. Dynamicsation - that moves the evolution from a rigid structure to a flexible one.
Cinematic Laws
6. Moving towards increasing ideality. Every stage of evolution will move closer to the ideal system.
7. Moving from complecated system to simplified system.
8. Elemination of redundant stages and Transition towards the super-system.

There are quite a few trends explored by TRIZ researchers, and many more are under the process of development. Different branches of study have different trends. Some of the interesting trends in engineering and technology field are as follows.

1. Transition from single to double to multiple
   Monolithic items are split into multiple components for efficiency and convenience. Single purpose products are made multi-purpose products. For example, pen with single color ink to pen with different color ink.
2. The transition from rigid to flexible to wave technologies.
   According to this trend the products are moving from rigidity to flexibility. The future stages of the product will be more and more flexible. For example, fixed gates to collapsible gates, fixed tables to openable and ajustable tables etc.
3. The transition from mechanical to thermal to electronic energy application.
   Machines are becoming more automated. Human operated machines are converted to petrol operated to battery operated machines. Many are converted to solar and atomic energy operated. For example, bi-cycle to motor-cycle, mechanical watch to battery operated watch, electric lights to solar lights, steam engine trains to diessel engine to electric engine etc.
4. Transition from large to small
   Products are moving from large size to small size. For example, Old generation computers were large, which were replaced by small personal computers. Current age laptops and palmtops are still smaller. This shows a trend towards future computers of even smaller size. Another example, Large clocks to small wrist watches to macro clocks.
5. Strait lines to curves
   Flat surfaces are made curved surfaces for convenience of use. For example, reclangular tv-remotes are made curved to fit better with the shape of human palms. Flat rests are made curved rests to give better support to the back.
6. Manual to automatic, or moving towards decreasing human involvement
   Products move towards reduced human involvements. As human time is precious products intend to work automatically without being operated by human beings. For example, thermostats in car engine fans, tv-timer to switch of tv automatically ater some time.
7. Transition towards controllability
   Products become more and more controllable. Better products have higher controllability. For example, electronic equipments, space shuttles.

• The main purpose of using trends is to predict the future technology and future evolution of a product or system. This helps us to develop the next generation products and increase competitive advantage.
• We can forecast the undiscovered customer needs. The products become more popular and customer oriented.
• This helps improving the product in the right direction, and make the product more successful. Helps improving the quality of the product.