Six Sigma means different things to different people, depending on where they are in the product development life cycle. It’ll mean something very different at the start of a program versus at the end of a program when a product reaches the manufacturing phase.

Six Sigma as a term was really brought to the forefront by Motorola as a methodology for achieving a very high level of quality in their manufacturing process. For a long time, Six Sigma and Six Sigma Certification were really focused toward the quality end in manufacturing, finding manufacturing issues, digging down to the root cause, and fixing the root cause of the issues. It sounds pretty straightforward, but there’s a whole set of tools and methods defined by the Six Sigma process that quality personnel has available to address manufacturing issues.

What Design for Six Sigma does is it takes the data-driven troubleshooting of the traditional Six Sigma techniques and applies it to the front-end design of a product. Michael Quinn of HS Design explains, “Design for Six Sigma says, ‘Well, if we could predict what issues we’re going to have going forward into a project, we can head off a lot of them, we can quantify them, we can look at them from a scientific basis, and put our design efforts where they really need to be so that by the time it hits manufacturing, it’s a much more robust system.’”

When potential clients are introduced to the Design for Six Sigma method, they often fear that it will add a lot of cost to the program. In fact, the opposite is true. At HS Design, our engineers and project managers work with clients to target the heart of their system and tackle the core difficulties first, identified as functions that are either New, Unique, or Difficult (the NUDs). After all, the ancillary items can be handled once the core functions are taken care of.

Michael explains that “It comes down to the essence of the methodologies, and this is what we educate our clients on; understanding the core functions that their product has to have and how they perform. This makes for a smooth moving project. Most clients usually appreciate that.”

He continues by saying, “If we break down the process correct for our prospects and clients, it does two things for them. They understand that we get what is difficult, and by telling them that we’re going to get to the core of their system, it tells them we’re going to try our best to understand the core of their system, not just because they tell us what they want but because we have to really dig in and be as or more knowledgeable than they are about what we’re developing for them.”

One great example of using the Design for Six Sigma method is that of a syringe system HS Design developed called Sympfiny®. It is a somewhat simple concept to dispense a powdered medication to a child via direct oral delivery. The problem that needed to be solved was to measure and dispense the microsphere dosage accuracy.

We sat down with them and said, “Okay. Well, you have so many different ways of actually measuring dose accuracy from a syringe. You’ve got the ISO standard for a liquid hypodermic syringe. You’ve got the USP standards, and there are a few different standards for measuring the accuracy of a drug product or a drug product from a delivery device.” We laid them out and said, “Here’s the area we have to deal with, we have to know which of these we’re talking about first.

It started with the clients saying, “We need 10% dose accuracy,” like, “Great. Is that 10% by weight? Is it 10% by volume? Is it a statistical 10%? Is it an absolute data set and nothing can have a data point out of 10%?” We had that conversation and chose the appropriate way to do it upfront. That was a start. From there, we were able to show that using those measurement techniques, we were able to apply the statistical techniques, the tolerance analysis, the manufacturing variances, and models into the CAD and into the device and prove in our early design reviews that this system will meet what you want out of it.

-As told by Michael Quinn, HS Design

The process can be very intense up front, but that intensity helps set the program on a good path. In the case of the Sympfiny® syringe, dosing accuracy was both a difficult function due to the small dosing volumes required and a unique function since no system to-date had ever dosed microspheres this way. Using Design for Six Sigma to identify dose accuracy as the most critical function and deploying the statistical tools to help select and develop the system to meet this function set the program on its path, and a successful path at that.