Critical to Quality: Attributes most important to the customer
Defect: Failing to deliver what the customer wants
Process Capability: What your process can deliver
Variation: What the customer sees and feels
Stable Operations: Ensuring consistent, predictable processes to improve what the customer sees and feels
Design for Six Sigma: Designing to meet customer needs and process capability
Methodology
Six Sigma has two key methodologies:DMAIC and DMADV. DMAIC is used to improve an existing business process. DMADV is used to create new product designs or process designs in such a way that it results in a more predictable, mature and defect free performance.
Also see DFSS (Design for Six Sigma) quality. Sometimes a DMAIC project may turn into a DFSS project because the process in question requires complete redesign to bring about the desired degree of improvement.
DMAIC
Basic methodology consists of the following five steps:
Define the process improvement goals that are consistent with customer demands and enterprise strategy.
Measure the current process and collect relevant data for future comparison.
Analyze to verify relationship and causality of factors. Determine what the relationship is, and attempt to ensure that all factors have been considered.
Improve or optimize the process based upon the analysis using techniques like Design of Experiments.
Control to ensure that any variances are corrected before they result in defects. Set up pilot runs to establish process capability, transition to production and thereafter continuously measure the process and institute control mechanisms.
