"How are you? You have been in Afghanistan, I perceive."

I've had to solve an interesting conundrum recently. I was approached by a major Chinese manufacturer of medical devices because they had a big surge of blood pressure returns during the winter seasons in North America. So my Chinese friends asked me to solve the problem in their inimitable manner: "How to do?

These kind of problems generally happen when products are not thought out properly during the design process. According to the simple principles of HCD (Human Centered Design), all aspects of a product (from the manufacture, the look, the components, the users, where it will be used, how it will be used, the kinds of users in that area, etc) should be considered before pen is put to paper.
You then get a product that works perfectly and delights the users every time, instead of getting a product that doesn't work in winter.

Duh... Sounds obvious doesn’t it?

Yes, that's right, it was simple electrical science that was needed to solve the Mystery Of The Batteries That Wouldn't Work In Winter And Caused Massive Returns.

" Elementary my dear Watson" said Sherlock Holmes " the interplay of ideas and the oblique uses of knowledge are often of extraordinary interest".

A few pages later, Sherlock also asks some pointed questions about Afghanistan, but you get the point…

Some of you might know that I am a graduate from the Catholic Seminary of Chicoutimi, in Quebec, Canada. A few hours North of Montreal, on the edge of the Saguenay River, Chicoutimi is cold in winter. I mean really cold. As in -30°C cold. As in getting your tongue stuck to mailboxes cold. I don't know if you've ever had to start a car in temperatures of -30 °C. Quite often it takes a while to turn over and catch because of the cold. That is because at sub-zero temperatures the electrolytes in the batteries have to work much harder and this uses up the power in the battery very quickly. Once the car has started, the power in the battery is re-generated by the engine and after a few minutes your battery is fully charged again.

However, a blood pressure monitor does not generate any power and only consumes it. The little rolling pump inside a blood pressure monitor needs at least 4 Volts and about 400 mA to run. In cold temperature, the 4 x 1.5V non-rechargeable batteries in the monitor are used up much more quickly than they should (because of the cold) and so after about 60 or 70 readings the batteries in the blood pressure monitor are used up and the device stops working, causing much angst for the user and many Mea Culpas from the manufacturer, who doesn't understand because "he tested the devices in his lab in China, (where the temperature was 35°C) and where he got about 300 readings out of one set of batteries". The problem is of course compounded by the fact that the Chinese factories generally test the devices using good quality alkaline batteries, but then supply them with the cheapest batteries they can find on the market, made by companies with attractive names like The Shanghai Scrap Plastic Corporation.

After analyzing the problem, it was quite easy to find a solution that involved redesigning the battery casing to be better insulated, and redesigning the circuitry so that the components would use less milliamps to operate. The same monitors now give about 450 readings on a set of batteries.

In this case the solution was easy to find and to fix, but because the products had not been carefully planned before production, there were 2 product recalls and huge bad publicity for the manufacturer.

In the words of Frank Lloyd Wright, "You can fix it on paper with an eraser, or you can fix it on the construction site with a sledge hammer".

Sounds obvious doesn't it...

Uwe Diegel
HealthWorks Global
uwediegel@mac.com
www.medactiv.com