Six Sigma

Design For Six Sigma (DFSS)

Six Sigma aims to improve the existing process by reducing or minimizing the causes of variation.

Design for Six Sigma (DFSS) efforts are focused on designing products and processes capable of reaching Six Sigma quality

Six Sigma methodology works within the framework of the existing process. It finds and fixes problems in the existing process.

DFSS aims at improving quality at the design phase of products and processes. DFSS is also used to redesign current products and processes.

Six Sigma is based on a strategic improvement methodology known as DMAIC, which stands for

Define,

Measure,

Analyze,

Improve, and

Control.

DFSS is based on DMADV methodology that utilizes the following phases:

Define, Measure, Analyze, Design, and Verify

DFSS is also identified by IDOV process that has the following phases

Identify, Design, Optimize, and Validate

Six Sigma improvement projects are based on the assumption that the design of current product, process, or service is correct and most economical, meets the needs and requirements of customers, and the design satisfies the functional requirements of the customer and market [ Nave,2002].

DFSS intends to create design that are :

Resource-efficient,

Capable of reaching very high yields,

'robust' to process variability, and

highly linked to customer demands

Six Sigma teams aim at achieving constant incremental improvements by reducing or minimizing causes of variation in the current process.

DFSS is design/redesign efforts. Its goal is to build quality early in the design stage or redesign existing product to improve current sigma level.

Six Sigma is considered reactive because it involves detecting and resolving problems.

DFSS is considered proactive; it involves preventing problems through prediction.

Six Sigma is based on manufacturing or transactional processes

DFSS focuses on product/process design, R&D, and marketing.

The benefits or cost savings from Six Sigma can be quantified rather quickly

DFSS benefits are long term and are difficult to quantify. It takes six to 12 months to realize the impact of DFSS effort.

Six Sigma optimizes individual CTQs

DFSS optimizes CTQs for optimal system level performance.

Six Sigma has component level view of product.

In Six Sigma, the product performance is assessed by 'build and test'

DFSS has system level view of product

DFSS uses modeling and simulation with optimal prototyping strategy to assess the product performance