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Akhilesh Gulati

Six Sigma

TRIZ in Reverse

The case of the smoking tomato plants

Published: Wednesday, June 26, 2013 - 09:16

Editor’s note: This article continues the series exploring structured innovation using the TRIZ methodology, a problem-solving, analysis, and forecasting tool derived from studying patterns of invention found in global patent data.

Belinda started the My Executive Council (MEC) meeting with the normal formalities and business agenda. There was animated discussion of some of the lessons learned and solutions adopted by members who had volunteered their organization’s issues as case studies during the past six months. They agreed that joining the MEC had proved quite beneficial to them thus far, especially citing the additional benefit of having a TRIZ consultant (Henrietta) facilitate meeting sessions. Getting the meeting back to order, Belinda directed everyone’s attention to Lindsay, stating that he wanted to share his issue with the council members.

Lindsay, who owned a wholesale nursery, informed the group that he had been talking to Henrietta over the past month regarding this issue he had, and in the process had not only found the root cause of his problem, but had also learned something new. This is what he wanted to share with the council members.

Spring was around the corner, and Lindsay’s plants were growing either outdoors or in greenhouses.  About a month ago, when checking up on his tomato plants in one of the greenhouses, he was shocked to see all of them showing signs of yellow mottling and rough edges turning down. This was troubling, as they could not afford to have something like this happen; local stores would be expecting their plants soon. He knew that they had been watering their plants regularly and giving them the right fertilizer treatment. But he wasn’t sure what could have caused this, so he took samples to the pathologist, who informed him that the plants suffered from double streak virus, most likely caused by the Tobacco Mosaic Virus (TMV). 

Virus diseases, in general, are not a routine problem in most tomato plantings because growers are usually aware of the precautions necessary to reduce the incidence. However, Lindsay was frustrated because he could not figure out how his tomato plants could have contracted TMV. He checked the greenhouse for tobacco plants and found nothing, nor any other source of tobacco.

When he approached Henrietta, she suggested that he try Principle No. 13 of TRIZ (Do it in reverse) on TRIZ itself: Take regular TRIZ and do it in reverse. Reverse TRIZ is used in anticipating bad things that may happen but are not yet happening. Or an alternate use is for a failure that has already happened, as in the case of his tomato plants.

The initial step in TRIZ is to first understand the ideal final result (IFR). In Lindsay’s case he wanted his plants to be healthy, but they were yellowing and showing unhealthy patterns. His IFR was “healthy plants,” which he didn’t have.

To use reverse TRIZ, we start with a clear IFR. Then, applying Principle No. 13 (do it backwards), turn the IFR upside down. Pretend that you want the opposite. Take this failure, exaggerate it, then make it even worse. Then you use TRIZ to see how you could make this happen. Of course, you want to make this happen with the existing resources. After all, the existing resources got together in an unanticipated way to create the undesired effect.

Lindsay said that they did not buy new equipment, and didn’t change their procedures to make bad stuff happen. The resources already existed; the question was to determine how they got together to produce the bad effect. How did the tomato plants catch TMV?  

Usually, with TRIZ, one likely generates two or three or four options to make this bad effect happen. Then one needs to go through the validation process. However, Henrietta suggested that the simplest possible option be tested first. Usually, it is the simplest thing that actually happens.

“Following her suggestion,” Lindsay said, “my IFR was healthy tomato plants free of TMV. Inverting this ideal state, I would want my plants to get TMV. Exaggerating the inverted ideal state, I would want all of my tomato plants not only to be infected with this virus, but also all dying of this virus. So I would want to create a condition that would infect all the plants and kill them fast.”

On the basis of frequency of occurrence, tomato diseases and disorders can be separated into two groups: those spread by humans, and those spread by insects. Lindsay was worried because the TMV is distributed worldwide and may cause significant losses in the field or greenhouse. TMV is one of the most stable viruses known, able to survive in dried plant debris for as long as 100 years. Many strains of TMV have been reported and characterized. Although TMV can be seed-borne in tomatoes, it is more readily transmitted mechanically by human activities, and is present in many tobacco products. Insects commonly living in the greenhouses or fields do not typically spread the tobacco virus.

After providing this background information, he continued, “My new problem statement became, ‘How can I infect all my plants quickly?’”  The virus spreads primarily by mechanical methods. Gardeners’ hands can become contaminated when they touch tobacco products or infected plants or weeds, thereby spreading the virus to healthy plants.  Which workers could have been touching tobacco products before they worked on the tomato plants? Lindsay’s organization followed a strict protocol regarding virus prevention. But then he realized that they often had graduate students doing internships. While following up with his staff, he discovered that a few of the students were smokers. Upon questioning them, he discovered that they had been sneaking smokes in the greenhouse; not only were their hands contaminated with tobacco, they were also infecting the air that surrounded these plants.

The cause for the TMV infection was now clear. TRIZ, or rather reverse TRIZ had helped Lindsay get to the root cause quickly and solve his problem. He was able to salvage his crop of tomato plants for his spring sales.

As the MEC prepared to wrap up, Lindsay was asked to summarize the reverse TRIZ procedure. He wrote the six steps of reverse TRIZ on a flip chart:
1. Identify the IFR
2. Invert the IFR, which now becomes the ideal state
3. Exaggerate the inverted ideal state
4. How would we accomplish this? What resources are required? Use the TRIZ tool to find methods for making this bad thing happen.
5. Validate the proposed cause and the presence of the resources
6. Use TRIZ to resolve any resulting problems

Lindsay concluded by saying what he found interesting was that he did not need to teach TRIZ to anyone, he just role-modeled the problem-solving behavior and facilitated them through the exercise. 

The meeting concluded with everyone noting down the six steps, eager to try them out on some of their own issues. The smoking tomato plants had poved an interesting way for the team to learn about reverse TRIZ.


About The Author

Akhilesh Gulati’s picture

Akhilesh Gulati

Akhilesh Gulati has 25 years of experience in operational excellence, process redesign, lean, Six Sigma, strategic planning, and TRIZ (structured innovation) training and consulting in a variety of industries. Gulati is the Principal consultant at PIVOT Management Consultants and the CEO of the analytics firm Pivot Adapt Inc. in S. California. Akhilesh holds an MS from the University of Michigan, Ann Arbor, and MBA from UCLA, is a Six Sigma Master Black Belt and a Balanced Scorecard Professional.