How can you maintain the repeatability of automated processes?

1 Identify and control sources of variation

The first step to maintain repeatability is to identify and control the sources of variation that can affect the automated process. These can be internal or external, and they can be classified into four categories: material, method, machine, and human. For each category, you should analyze the factors that can cause variation, such as the quality, quantity, and properties of the material, the parameters, settings, and procedures of the method, the performance, maintenance, and calibration of the machine, and the skills, training, and supervision of the human operators. Then, you should implement measures to minimize or eliminate these factors, such as standardizing the material specifications, documenting and following the method instructions, monitoring and adjusting the machine conditions, and providing feedback and training to the human workers.

2 Apply statistical process control

The second step to maintain repeatability is to apply statistical process control (SPC) to monitor and control the automated process. SPC is a method that uses statistical tools and techniques to measure and analyze the variation of the process output. By collecting and plotting data on control charts, you can identify whether the process is in a state of statistical control, meaning that it only exhibits common or random variation, or whether it is out of control, meaning that it exhibits special or assignable variation. If the process is out of control, you can use SPC to detect and correct the causes of variation, such as shifts, trends, or cycles. SPC can also help you to improve the process capability, which is the ability of the process to meet the specifications or requirements of the customer.

3 Implement continuous improvement

The third step to maintain repeatability is to implement continuous improvement to optimize the automated process. Continuous improvement is a philosophy and a practice that aims to increase the efficiency, effectiveness, and quality of the process by applying the Plan-Do-Check-Act (PDCA) cycle. The PDCA cycle consists of four stages: plan a change or improvement, do the change or improvement, check the results and effects of the change or improvement, and act on the findings and feedback to standardize or modify the change or improvement. By applying the PDCA cycle, you can continuously monitor and evaluate the performance of the automated process, identify and solve problems, and implement best practices.

4 Use simulation and testing

The fourth step to maintain repeatability is to use simulation and testing to validate and verify the automated process. Simulation and testing are methods that use models and experiments to mimic and evaluate the behavior and outcomes of the process under different scenarios and conditions. By using simulation and testing, you can assess the feasibility, functionality, and reliability of the process design, identify and eliminate potential errors and defects, and optimize the process parameters and settings. Simulation and testing can also help you to anticipate and prepare for changes and uncertainties, such as variations in demand, supply, or environment, and to ensure the robustness and adaptability of the process.

5 Document and communicate

The fifth step to maintain repeatability is to document and communicate the information and knowledge related to the automated process. Documentation and communication are essential for ensuring the consistency, transparency, and traceability of the process. By documenting and communicating, you can record and share the process specifications, requirements, instructions, data, results, and feedback, as well as the process changes, improvements, and best practices. Documentation and communication can also facilitate the collaboration, coordination, and learning among the process stakeholders, such as the process designers, engineers, operators, managers, and customers.

6 Review and audit

The sixth step to maintain repeatability is to review and audit the automated process periodically. Review and audit are methods that use standards and criteria to measure and evaluate the performance and compliance of the process. By reviewing and auditing, you can check and verify whether the process meets the expectations, goals, and requirements of the process stakeholders, as well as the regulations, policies, and norms of the industry and the society. Review and audit can also help you to identify and correct any deviations, errors, or defects that may affect the repeatability of the process, and to ensure the continuous improvement of the process quality and reliability.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?