Shipulski On Design

Posts Tagged ‘Product Design’

There is no question that Six Sigma helps companies make money. So much so that everyone in the manufacturing community knows the five hallowed letters: DMAIC (Define, Measure, Analyze, Improve, Control). It’s straightforward and fully wrung-out. But that’s not the case for the wicked step sister Design for Six Sigma (DFSS). She’s fundamentally different and more complicated. To start, it’s an alphabet soup out there. Here are some of the letters: DMADV, DMADOV, IDOV, and DMEDI, and there are likely more. Does everyone know these letters and what they stand for? Not me. But here is the fundamental difference: with DMAIC the thing to be improved already exists and with DFSS the thing to be created does not. In essence, there is no formalized problem to solve. So what you say?

With DMAIC it’s all about reducing variation relative to the specification; with DFSS there is no specification. In fact, there is no product yet a process on which we can measure variation. First the product itself must be created and its functional performance must be defined over a range of parameters. Only then is manufacturing variation measured relative to the range functional parameters (DMAIC). But I got ahead of myself.

Before creating the thing that does not exist and make sure it meets the functional specification, some mind reading of customer needs is required, an even lesser defined thing. So, there is a round of reading customers minds followed by round of creating something that does not exist to satisfy the customer needs define in the mind reading sessions. Oh yea, then the tolerances must be defined so the product always functions the way it’s supposed to. All this before we turn the DMAIC crank.

My point with all this is to help set expectations when dealing with product design/DFSS. It is wrong to expect the predictability and standardization of DMAIC when doing product design/DFSS.  It’s different.  Product design/DFSS is not the same turn-the-crank kind of operation. That is not to say there is zero predictability and standard work or that predictability is not something to strive for. It’s just different. With product design the problems are unknown at the start and sometime even the fundamental physics are unknown. Please keep this in mind when your product development projects are late relative to hyper aggressive, non-work-content-based schedules or when new products don’t meet the arbitrary cost targets.

Improving product robustness is straightforward and difficult. Here’s how to do it.

Identify specific failure modes, prioritize them, and go after the biggest ones first. Failure modes can be identified through multiple sources. Warranty data is sometimes coded by failure mode (more precisely, symptom type), so start there. The number one failure mode in this type of data is typically “no problem found”, so be ready for it. Analysis of the actual products that come back is another good way. Returned product is routed to the appropriate engineer who analyzes it and enters the failure mode into a database. A formal design FMEA generates a list of prioritized failure modes through the risk priority number (RPN), where larger is more important. To do this, engineers are hauled into a room and a facilitator helps them come up with potential failure modes. One caution – the process can generate many failure modes, more than you can fix, so make the top five or ten go away and don’t argue the bottom fifty. It makes no sense to even talk about number eleven if you haven’t fixed the top ten. But the best way I have found to identify failure modes (problems) that are meaningful to the customer is to ask the technical services group for their top five things to fix. They will give you the right answer because they interact daily with customers who have broken product. They won’t expect you to listen to them (you never listened before), so surprise them by fixing one or two on their list. They will be grateful you listened (they’ll likely want to buy you coffee for the rest of your career) and your customers will notice.

Once failure modes are identified, define the physics of failure – why the product breaks. This is tough work and requires focused thought and analysis. If, when you break the product, it “looks like” the ones coming back from the field, you have defined the physics of failure. This is the same thing as replicating the problem in the lab. Once that’s defined, create an automated test rig or experimental setup that breaks the product in a way that captures the physics of failure. I call this test rig a robustness surrogate because it stands in for the actual failure mode seen in the field. The robustness surrogate should break the product as fast as possible while retaining the physics of failure so you can break it and fix it many times before product launch. The robustness surrogate should be designed to break the product within minutes, not hours or days – the faster the better.

To know if product robustness is improved, the baseline (or existing) design is broken on the robustness surrogate. The new design must survive longer on the robustness surrogate than the baseline design. The result is A/B data (baseline design/ new design) that is presented at the design review using a simple bar graph format which I call big-bar-little-bar. Keep improving robustness of the new design even if it outperforms the baseline design by a factor of ten – that’s not good enough for your customers.

Don’t stop improving robustness until you run out of time, and don’t stop if you meet the arbitrary MTBF specification. Customers like improved robustness, and in this case too much of a good thing is wonderful.

Using this method, I reduced warranty cost per unit by 75% over a five year period. It worked.

In a previous post I defined the term brand-damaging threshold and said I’d talk about how to improve product robustness. So, here goes.

Every company is at a different stage in their formalized product robustness efforts, so it’s challenging to talk meaningfully to everyone. But there are two especially meaningful principles that have served me well through the years.

I had the privilege of working with Don Clausing – Total Quality Design, The House of Quality, Enhanced QFD, and Robust Quality. I vividly remember the conversation where Don shared one of his secrets. As we watched a robustness test run, Don, in his terse way, barked out a guiding principle of improving product robustness. He said:

“Improve robustness at the expense of predicting it.”

I asked Don what the hell he meant (he liked to make his students work for it), and after some prodding, he went on to explain why it’s so important. He said people spend far too much time running tests to predict robustness and then spend even more time calculating mean time between failures (MTBF). If that’s not enough, then they spend time arguing about MTBFs and the confidence intervals. He said companies should dedicate all their time and energy improving robustness. “That’s what matters to the customer,” he said. And then he continued with something like: “Predicting robustness is worse than a simple waste of time.” (He wasn’t that polite.) But I still didn’t get it. What’s the big deal about predicting robustness? Read the rest of this entry »

Lean has been beneficial for many companies, helping improve competitiveness and profitability. But, lean has not been nearly as effective as it can be because there is a missing ingredient – product design. Where lean can reduce the waste of making and moving parts, product design can eliminate the parts altogether; where lean can reduce setup times for big machines, product design can change the parts so they no longer need the big machines; where lean can reduce inventory, product design can eliminate it by designing out parts; where lean can make the supply chain more efficient, product design can radically shorten it by designing out the long lead time elements.

The power of product design is even more evident when considering the breakdown of product cost. Here is some data from Nick Dewhurst taken from multiple-hundred DFMA analyses showing the typical cost breakdown of products.

Of the three buckets of cost, material cost is by far the largest 74%, and this is where product development shines. Product design can eliminate 40 to 50% of material cost resulting in radical cost savings. Lean cannot. I will go a bit further and say that material cost reductions are largely off limits to the lean folks since it requires fundamental product changes.

Side note – Probably most surprising about cost breakdown data is labor cost is only 4%. Why we move our manufacturing to “low cost countires” to chase 50% labor reductions to net a whopping 2% cost reduction is beyond me, but that’s for a different post.

Let’s face it – material cost reduction is where it’s at, and lean does not have the toolbox to reduce material cost. There’s no mystery here. What is mysterious, however, is that companies looking to survive at all costs are not pulling the biggest lever at their disposal – product design. Here is a bit of old data from Ford showing that Product Design has the biggest lever on cost. We’ve know this for a long time, but we still don’t do it.

Clearly, the best approach of is to combine the power of product design with lean. It goes like this: the engineers design a low cost, low waste product that is introduced to the production line, and the lean folks improve efficiency and reduce cost from there. We’ve got the lean part down, but not the product design part.

There are two things in the way of designing low cost, low waste products in a way that helps take lean to the next level. First, product development teams don’t know how to do the work. To overcome this, train them in DFMA. Second, and most important, company leaders don’t give the product development teams the tools, time, and training to do the work. Company leaders won’t take the time to do the work because they think it will delay product launches. Also, they don’t want to invest in the tools and training because the cost is too high, even though a little math shows the investment is more than paid back with the first product launch. To fix that, educate them on the methods, the resource needs, and the savings.

Good luck.

Like you, I have been thinking a lot about the recession.  We all want to know how to move ourselves to the other side, where things are somewhat normal (the old normal, not the new one).  Like usual, my mind immediately goes to products.  To me, having the right products is vital to pulling ourselves out of this thing.  There is nothing novel in this thinking;  I think we all agree that products are important.  But, there are two follow-on questions that are important.  First, what makes products “right” to move you quickly to the other side?  Second, do you have the capability to engineer the “right” products?

The first question – what makes products “right” for these times?  Capacity is important to understanding what makes products right.  Capacity utilization is at record lows with most industries suffering from a significant capacity glut.  With decreased sales and idle machines, customers are no longer interested in products that improve productivity of their existing product lines because they can simply run their idle machines more.  And, they are not interested in buying more capacity (your products) at a reduced price.  They will simply run their idle machines more.  You can’t offer an improvement of your same old product that enables customers to make their same old products a bit faster and you can’t offer them your same old products at a lower price.  However, you can sell them products that enable them to capture business they currently do not have.  For example, enable them to manufacture products that their idle machines CANNOT make at all.  To do that means your new products must do something radically different than before; they must have radically improved functionality or radically new features.  This is what makes products right for these times.

On to the second question – do you have the capability to engineer the right products?  Read the rest of this entry »

Part Cutters — Design News

The engineers at Hypertherm Inc., a maker of plasma cutting systems,know a thing or two about cutting metals. They also know how to cut cost. A lot of cost. While redesigning one of the company’s best-selling plasma cutting systems, they managed to reduce parts’ count from more than 1,000 components to fewer than 500. System assembly time fell from 20 hours to less than five. And the output from the company’s existing assembly operation quadrupled — without any additional floor space or an expensive second shift. Bottom line: the redesign saved the company about $5 million in assembly costs over the past 24 months alone, according to Engineering Manager Mike Shipulski. Read the rest of this entry »

Redesigns get radical improvements using DFMA

Hypertherm, Inc. of Hanover, NH, is among the world’s foremost manufacturers of plasma arc cutting equipment. Founded in 1968 with a staff of two, the company today has 750 employees, with subsidiaries, sales offices, and distributors in multiple countries. All technology development, product development, and manufacturing is done in the Hanover area.

View of the new HyPerformance Plasma HPR130 plasma cutter from Hypertherm. The company used Design for Manufacture and Analysis (DFMA) methodology to radically redesign — and improve — the system’s manufacturability. In the new plasma cutter, system subassemblies took 45% to 89% less time to put together. Assembly floor space opened up by 40%. Warranty cost went down 83%. Cost savings amounted to $5 million over 24 months, which helped the company achieve record earnings and its highest profit sharing on record.

Hypertherm’s products range from lightweight, manual plasma cutting equipment to highly mechanized systems that operate with CNC cutting machines. Its advanced technology serves a global customer base in every industry that depends on quality and reliability in high-temperature metal cutting, such as shipbuilding, construction, farm equipment, rail car and truck manufacture, and plant maintenance.

Recently, Hypertherm engineers tackled a project of mammoth proportions when they remodeled the company’s highly successful HD3070 plasma cutting system — and ultimately created the new HyPerformance Plasma HPR130 plasma cutter. Before the redesign project, the HD3070 sold well and was widely regarded as a standard for robust, high-precision cutting in the industry. Hypertherm wanted to make the product even better.

“We started with a vision to make a radical improvement in product performance coupled with a radical reduction in product cost,” says Mike Shipulski, director of engineering for Hypertherm. He believed that using the methodology of Design for Manufacture and Analysis (DFMA) would help identify unnecessary parts, highlight assembly difficulties that Read the rest of this entry »