Statistical process control (SPC) is a method of monitoring and improving the quality and performance of a product or process by using statistical tools and techniques. SPC can help product engineers to reduce variation, optimize design parameters, and identify and eliminate defects. But how can you integrate SPC with your product design process? Here are some steps to follow.
The first step is to define the objectives of your product design project. What are the customer needs and expectations? What are the functional and technical requirements? What are the quality standards and specifications? How will you measure and evaluate the product performance? These questions will help you to set the scope, goals, and criteria for your product design.
The next step is to plan the design process. How will you generate, evaluate, and select the best design alternatives? What are the resources, tools, and methods you will use? How will you manage the risks, uncertainties, and changes? How will you communicate and collaborate with your stakeholders? These questions will help you to create a clear and structured design plan.
The third step is to apply SPC tools and techniques throughout the design process, such as design of experiments (DOE), control charts, process capability analysis, failure mode and effect analysis (FMEA), and root cause analysis (RCA). DOE is a method of testing and optimizing the effects of different design factors and levels on the product performance and quality. Control charts are graphical tools to monitor and control the variation and stability of a product or process over time. Process capability analysis assesses how well a product or process meets the quality specifications and customer expectations. FMEA is a method of identifying and prioritizing the potential failures and their causes and effects on the product or process. RCA is a method of finding and eliminating the underlying causes of a problem or defect.
The fourth step is to validate and verify the design. Validation involves confirming that the product meets customer needs and expectations, while verification ensures that the product meets functional and technical requirements. To validate and verify the design, you can use methods such as prototyping, testing, inspection, and review. Prototyping involves creating and testing a physical or virtual model of the product before final production. Testing is a way to measure and evaluate the product performance and quality under different conditions. Inspection examines and checks the product for any defects or deviations from specifications. Lastly, review evaluates and approves the design by stakeholders.
The final step is to document and improve the design. This involves recording and reporting design information, data, results, and decisions, as well as analyzing and applying feedback, lessons learned, and best practices to enhance the design quality and performance. To do this, you can use various methods such as creating and maintaining design documents, collecting input from customers and users, capturing knowledge from the design project, and following proven design standards.
Initial Training and Awareness - Educate the design team on SPC principles. I recall conducting workshops to familiarise my team with SPC concepts, ensuring a solid foundational understanding. Data Collection Plan - Establish a robust data collection strategy. In one project, we identified key variables affecting product quality early in the design phase. Integration into Design Process - Embed SPC tools like control charts into the design workflow. We used these tools to monitor critical parameters during prototype testing. Feedback Loops - Create mechanisms for continuous feedback. Regular design reviews incorporating SPC data helped us refine designs iteratively.