Six sigma

Six Sigma Approach

A Lean Six Sigma Improvement methodology is a systematic and robust approach to improvement based on the ‘Voice of the Customer’.
The five key principles of Six Sigma are:
• Understand the Critical to Quality (CTQ) requirements of our customers and stakeholders
• Understand our processes ensuring they reflect the CTQs
• Manage by fact
• Involve and equip the people in the process
• Undertake improvement activity in a systematic way

A Six Sigma Improvement Journey follows an eight-step improvement process, mapped against DEFINE, MEASURE, ANALYSE, IMPROVE, CONTROL (DMAIC) methodology.

DMAIC

Define
Step 1 – Select the Problem
DMAIC projects start with a problem that needs to be solved. You must ensure that everyone involved has a clear understanding of their role, why the project is being undertaken and what it’s trying to achieve.
Key outputs for step one:-
• Improvement Charter
• The CTQs
• SIPOC Diagram
• Stakeholder Analysis
• Elevator Speech
• Risk Assessment
• Storyboard
• Communications Plan

Measure
Step 2 – Understand the current situation
It’s likely that the work you have done in Step 1 is based on what you think the problem is. Now you need to clarify things by understanding how the work gets done and how well it gets done.
Key outputs for step two:-
• Confirm the CTQs
• Confirm the SIPOC
• Deployment Flow-chart
• Value Stream Map
• Output Measures (Ys)
• Input & Process Measures (Xs)
• Data Collection Plan
• SPC Control Charts
• Baseline Performance
• Updated Charter
• Updated Storyboard
• Updated Communications Plan

Analyse
Step 3 – Identify & check the possible causes
Now you know what’s happening, it’s time to generate ideas about why. But don’t jump to conclusions. It’s important to check possible causes using data to verify the ideas generated and manage by fact. In verifying the vital few, you may find ‘the usual suspects’ are not guilty at all! Identifying and removing the root causes of a problem will prevent it happening again.
Key outputs for step three:-
• Value-Add Analysis
• Identification of Waste
• Fishbone Diagram
• Confirmed X measures
• Data Displays
• The Root Cause
• Updated Charter
• Updated Storyboard
• Updated Communications Plans
• Stakeholder Analysis

Step 4 - Generate Possible Solutions
Having identified the root cause of the problem you can generate ideas to tackle it, though the solution may be evident from the work done in the previous two steps. Do make sure that your proposed solutions address the problem and its cause.
Key outputs for step four:-
• Potential Solutions
• New Deployment Flow Chart or;
• New Value Stream Map
• Updated Storyboard
• Updated Communications Plans

Improve
Step 5 – Select the Solution
It’s time to choose the most appropriate solution. In doing so, you will need to take account of the results from any testing or piloting, and the criteria you’ve identified as important. These are the factors such as customer priorities, cost, speed and ease of implementation. It may seem obvious, but make sure your solution addresses the problem and that customers will see a difference if it’s adopted.
Key outputs for step five:-
• The solution
• Draft Cost Analysis
• Updated Storyboard
• Updated Communications Plan
• Stakeholder Analysis

This step seeks to ensure the smooth implementation of your chosen solution. The main focus, though, is on prevention – causing something not to happen. Carrying out a more detailed pilot is likely to be helpful.
Key outputs for step six:-
• A Pilot
• Implementation Plan
• Updated Charter
• Updated Storyboard
• Updated Communications Plans
• Stakeholder Analysis

Control
Step 7 – Implement, Standardise and Control
Depending on the scope of the project, implementation could be relatively simple or difficult. Either way, this step looks to help you hold the gain. All the key elements of Process Management should be coming together.
Key outputs for step seven:-
• The Solution in place
• Updated Documentation
• Training Plan
• Data Collection Plan
• SPC Control Chart
• Effective Handover
• Updated Storyboard
• Updated Communications Plans

Step 8 – Assess Achievements and Lessons
This is where you take stock of what’s been achieved and how. Depending on the nature of the project, you may need to prepare for a formal update to management. Make sure you remember to recognise the efforts of the people who have been involved in the project. And don’t forget to, apply the learning from this project to the next one you tackle.
Key outputs for step eight:-
• Completed Storyboard
• Key Lessons

Six Sigma Green Belt Project
Reduce Design Iterations Post Design Freeze

The following presentation is a typical Six Sigma Green Belt project using the above-mentioned approach. The aim of the project was to reduce design iterations post design freeze on ‘A’ surface projects. From the measure phase it was found that the most costly modifications were carried out on the buttons due to illumination issues. This was due to lack of availability of design tools which aid the designer to predict the final intensity that can be achieved. The process was improved by using a jig which simulates all the interactions of the various parameters which affect illumination. Eventually, with the help of DoE a user friendly excel software was achieved. A further recommendation to further reduce tool modifications is to train the engineers on illumination software analyses.

Conclusions and Recommendations

Using the six sigma methodology it was tracked a systematic approach to reduce the design iterations post design freeze. Another conclusion obtained from this study is that now the modifications are categorized by part. Therefore this study can be prolonged on the other components