ISO 9000:2015 defines quality as the degree to which a set of inherent characteristics and features of a product fulfills a stated or implied need, expectation, or requirement. During the creation of a product or construction of a structure, plenty of factors determine the level of quality attained. These include design, process (method of operation), facilities (tools, materials, equipment, supplies, instruments, and other resources), and instructions (directions). On the other end of the spectrum, precision (which refers to the closeness of results taken over time), conformity, reliability, accuracy, proficiency, and timing are widely recognized as measures of quality.
Design plays a foundational role in the success of the creation process. It aims to fulfill a need by defining the blueprint builders or manufacturers use to create a product or building. It sets the tone for the degree of excellence of everything that follows, all other factors held constant. As such, the design team needs to perform constant checks to identify and correct errors in dimensions, incorrect notes and references to details on the drawings, discrepancies between project drawings and project specifications, and other problems.
Today, most design professionals use CAD software to create designs. By their very nature, CAD tools and software are generally assumed to be 100% precision. Indeed, they can produce the same design feature repeatedly with no variations. But the human aspect can – and often does – introduce the possibility of errors or non-compliance with standards. Fortunately, design professionals can implement quality assurance (QA) in CAD processes to minimize or eliminate errors and other issues affecting quality. In this article, we delve into the role of QA, quality control (QC), and technology in enhancing the quality of CAD designs.
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Fundamentals of Quality Assurance in CAD
What is Quality Assurance in CAD?
Quality assurance (QA) in CAD refers to all the planned and systematic activities needed to provide satisfactory confidence that a CAD design will perform adequately and conform to the quality requirements and that the standards, practices, techniques, procedures, approaches, and methods of a CAD design process or CAD design project are implemented correctly. Quality assurance in CAD is carried out at the design stage, preventing mistakes and defects or avoiding errors that may come up during construction, production, or usage.
Today, in most companies, QA has merged into or is part of quality management systems. This means such companies have adopted the ISO 9000 family of standards, globally recognized standards for quality management and QA. ISO 9000 provides recommendations that help organizations enhance the quality of their products and services. It also provides a template for how to meet customers’ expectations consistently.
Goals of Quality Assurance in CAD
Quality assurance in CAD aims to:
- Supply products or deliver structures that fully comply with statutory, regulatory, and customer requirements
- Ensure the quality of the final product or structure
- Improve market competitiveness
- Increase customer satisfaction
- Avoid failures
- Provide clear and simple working, construction, or production structures
- Realize the desired product properties
- Promote the use of standard design practices and standards to enable other designers to reuse the design
Design Methods and Principles Contributing to QA in CAD
Generally, rules, principles, and guidelines of design contribute to quality assurance in CAD. This is because they provide systematic design methods that help influence product quality. They achieve these by helping designers include measures for avoiding failures. They also help downstream professionals who follow the instructions in the designs to realize the desired product properties. Moreover, rules, principles, and guidelines provide simple and clear working and construction structures anchored in comprehensive CAD designs.
The design methods resulting from the rules, principles, and guidelines of design and, by extension, quality assurance in CAD include:
- Clear and simple design solutions that help the reliable prediction of effects
- Direct safety strategies (such as redundancy, safe-life design, and fail-safe) and indirect safety principles (such as safety systems and safety devices) provide essential opportunities to attain environmental protection, accident prevention, reliability, and durability
- Fault-free design facilitates failure reduction
- Design to standards which ensures compliance with standards
- The principle of matched deformations ensures uniform load distribution. It works by determining the geometries of and force directions acting on surfaces in such a way that ensures interfacing surfaces deform in the same directions and with the same magnitudes.
- The principle of stability includes measures to compensate for or reduce the disturbing factors or forces acting on a part, component, or system
- The principle of self-help enables designers to create self-protecting solutions to design problems, with these solutions either altering load paths in case of overloading or compensating for excess stresses. This principle aims to use the operating and disturbing effects of loads to support the primary function of a part or component.
- Design to allow for expansion and creep
- Design against corrosion
- Design to minimize wear
- Design for production and assembly
- Design for aesthetics
- Design for ergonomics
CAD Quality Assurance Program
What is a CAD Quality Assurance Program?
A CAD quality program establishes the overall measures to accomplish the general objectives of a CAD project. It also offers a disciplined approach to all design activities affecting quality. These activities can include verifications that designers have satisfactorily performed every assigned task and have taken corrective measures to address emerging issues.
Additionally, the program comprises tools and actions designed to ensure that methods for designing parts, assemblies, buildings, or products are unambiguous, clearly presented, accepted, and applied uniformly and consistently throughout the design stage and later in the project lifecycle. Moreover, a quality assurance program serves as documentary evidence demonstrating that the CAD design has achieved the required quality.
However, while it is essential to establish and implement a quality assurance program, it does not guarantee that quality is attained. Instead, the responsibility to ensure quality rests with the designers assigned the design task. It does not rest with those charged with ensuring, through verification, that quality has been achieved.
That said, verification is still vital as it helps identify issues the designer may have missed or overlooked. As such, it is crucial to designate a QA manager who administers the QA program.
Key Elements of a CAD Quality Assurance Program
For a CAD quality assurance program to be effective and deliver the various benefits described above, it must include the following key elements:
- Description of requirements for activities related to the performance of the project
- Procedures and necessary instructions for creating CAD drawings and models
- Procedures for checking drawings and documents created with input from various disciplines, e.g., architects, structural engineers, mechanical engineers, electrical engineers, and more
- Periodical reviews by management
- Organizational structure and how roles interface (organizational interfaces)
- Responsibility and authority of various personnel as well as communication structure
- Staffing and training
- Document control and document change control
- Design control and verifications
- Document preparation, review, and approval
- Document release and distribution
- Design interface control
- Corrective actions
- Records and preparation of QA records
- Collection, storage, and preparation of QA records
- Audits and scheduling of audits
Including these elements ensures that the CAD quality assurance program is defined and realized, helping implement quality assurance. Naturally, however, projects usually encompass multiple other processes beyond design. These can include material selection, procurement, storage, loading, and testing, as well as production and other downstream processes. In this regard, a comprehensive quality assurance program can include the following additional non-CAD elements:
- Procurement control
- Supplier evaluation and selection
- Control of purchased services and products
- Identification and control of materials, parts, and components
- Handling, storage, and shipping
- Maintenance
- Process control
- Inspection and test control
- Inspection and test program
- Calibration and control of test and measuring equipment
- Indication of inspection, test, and operating status
- Non-conformance control, review, and disposition
Quality Checks and Controls in CAD
What is Quality Control?
Quality control or QC refers to a system or a set of specific procedures intended to verify and maintain the desired level of quality as well as detect and correct mistakes/defects. It ensures the approaches, techniques, methods, and processes designed for a project are followed correctly. Therefore, the activities that constitute QC help prevent or eliminate causes of quality issues and unsatisfactory performance.
To achieve its objective, QC uses customer requirements, design specifications, and standards as benchmarks of the quality of the product or structure. But for quality control to be effective, the following considerations are necessary:
- Careful planning
- The use of proper equipment
- Continued inspection
- Corrective action
QC is part of QA. Thus, while the QA manager administers the procedures for ensuring quality, as outlined in the quality assurance program, this is not the case with quality checks and controls. Therefore, within the more narrowed domain of QC, the responsibility for carrying out quality checks and quality control falls on those carrying out the CAD design. This group of professionals includes design professionals, design team leaders, and design managers.
Objectives of Quality Control in CAD
Quality control in CAD aims to:
- Check the critical aspects of design quality against a set of specifications or standards
- Satisfy customer needs
- Translate customer requirements and specifications into product quality characteristics that serve as a benchmark
- Decrease the design and development cost in terms of money and time
Quality Checks and Quality Control Activities in CAD
There are several quality checks and quality control activities in computer-aided design. These activities aim to solve a common human weakness – that they can make mistakes. In this regard, they help identify design issues that need correction, allowing designers to modify the designs to ensure precision by rectifying errors or guarantee compliance with regulatory standards. Only then can the design be approved, enabling it to be used for downstream work.
The quality checks and quality control activities in CAD include:
- Design review or audit
- Full independent design checking
- Inter-discipline review
Design Review or Audit
A design review is intended to check whether a design can suitably and effectively fulfill its intended purpose. During a design review, professionals:
- Evaluate the design to ascertain whether it fulfills requirements and complies with standards
- Verify that the outcomes of the design process have been fulfilled
- Identify design issues that may affect quality and performance
There are two levels/types of quality checks involved in a design review, with their selection depending on the circumstance. However, they are based on the premise that two heads are better than one. In the first one, a designer’s colleague (within the design office) can independently and rigorously check the CAD design. The colleague’s investigation can reveal errors or identify better ways of capturing the designer’s intent.
The second level/type of quality checks involves independent checks by an expert engineer. The engineer checks the CAD design against requirements, standards, and detailed design criteria. They also analyze the structural behavior of the product or structure and formulate a professional opinion that captures the adequacy of the CAD design.
Inter-discipline Review
Some projects require the input of designers from multiple disciplines. For instance, the design of a car involves the input of automotive aerodynamicists, exterior designers, interior designers, manufacturing engineers, and automotive engineers, just to mention a few. This is also the case in other domains such as construction, aircraft manufacturing, and design and manufacture of devices.
In other cases, multidisciplinary personnel are the product of the strategic outsourcing of certain CAD design services to specialists. Whatever the reason, the existence of such expansive teams can cause confusion and misalignments if they do not use the same design criteria. To solve this issue, inter-discipline review is necessary.
Inter-discipline review examines each discipline’s designs to ensure they all use the same design criteria. It also assures that the designs are intended to meet similar requirements. Combined, the interventions supported by inter-discipline review help ensure the quality of designs.
Full Independent Design Checking
Full independent design checking uses independently derived methodologies to analyze the design. It does not merely review the designer’s methods and/or calculations. In this regard, it increases the likelihood of mistakes being found early in the design process, ensuring the precision of both the design and downstream processes. Full independent design checking also provides a second opinion that reduces design risks and uncertainties. Moreover, the second opinion adds confidence to the designer and client that their design sufficiently conforms to safety, quality, and performance standards.
Technology’s Role in Enhancing CAD Quality Assurance
There are two approaches you can consider to complete quality control and quality assurance in CAD. You can elect to take the manual route. This option is, however, only feasible if you are working with just a handful of CAD designs. But if you are part of a project that generates tens or hundreds of designs, manually carrying out QC and QA activities can become daunting. In fact, and ironically so, the workload can increase the propensity to make mistakes. This is where technology comes in: to increase efficiency, reduce the chances of making mistakes, and enhance or guarantee quality.
Technologies for Quality Assurance in CAD
Today, numerous technologies enhance CAD quality assurance processes, supporting quality improvements. They include:
- Reliability analysis: Computer-supported reliability analyses help predict component and machine lives and the likelihood of failure.
- Tolerancing: Computer-based tools help designers define and analyze tolerances, ensuring precision.
- Design optimization: Other tools enable designers to optimize their designs with the aim of meeting complex objectives and standards requirements.
- Stress and deformation analysis: Computer-aided engineering (CAE) tools integrated into CAD and 3D modeling software like SolidWorks, Creo, Fusion 360, CATIA, FreeCAD, Inventor, Solid Edge, NX, and more analyze deformations and stresses of parts and structures under various load conditions to optimize them for performance, material utilization, safety, and other properties. Such analyses improve the quality of the designs.
- AI-powered quality assurance in CAD: The role of artificial intelligence (AI) in computer-aided design extends beyond generative design to power quality assurance in CAD. Professionals can use AI and machine learning to classify a wide range of data, including designs, process plans, and documents, aiding in data management. Moreover, AI models trained using a large dataset of CAD models and sketches can offer corrections when designers make unreasonable operations.
- Quality management system (QMS) software: This software can detect risks and failures in designs and other downstream processes in a product’s lifecycle. It can also support compliance, help quality management professionals mitigate risks, and enable continuous process improvement.
QA/QC Tools in CAD
Here are a few examples of tools that perform the above quality checks and quality assurance activities:
SolidWorks Design Checker
SolidWorks Design Checker is a built-in SolidWorks tool that checks design elements against predefined design criteria to ensure they meet laid-out requirements. Specifically, the tool verifies sketches, materials, fonts, and dimensioning standards to ensure they align with the design criteria. This way, it can identify and sometimes repair errors in data that could affect the simplification, interoperability, and reusability of CAD models. It is, however, worth pointing out that this tool is only available in SolidWorks Professional and SolidWorks Premium.
Creo ModelCHECK
Creo ModelCHECK is an application that runs within Creo Parametric. It uses a configurable list of company best modeling practices and design standards to analyze parts, drawings, and assemblies, helping verify compliance. It then generates a dynamic HTML report, which appears in Creo Parametric’s embedded browser. This report contains the results of the analysis and recommends improvements.
CAx Quality Manager and NX Checkmate
Third-party developers have developed applications to help NX users to undertake quality checks. These tools include:
- CAx Quality Manager by DOCUFY: It performs more than 400 best-practice checks, providing data that users can use to optimize their CAD designs and implement changes.
- NX Checkmate: It is a CAD QA tool that helps users enforce CAD standards, maintain CAD methodologies, and adhere to design best practices
PrescientQA
PrescientQA is an integrated QC and QA application for CATIA V5. It is designed to detect, analyze, correct, and even prevent errors and inaccurate, incomplete, or inconsistent design data. As a result, these interventions minimize engineering change orders.
iCHECK IT
Developed by Tata Technologies, iCHECK IT is a QA software for CATIA V5. It automates the QA process. Specifically, it conducts over 330 standard checks, helping designers enforce company CAD standards. It, therefore, prevents design issues, ensures consistent deliverables from suppliers, and provides advanced reporting and tracking of design quality. Moreover, it enhances productivity, given its support for automation.
ICEM Surf
ICEM Surf is Dassault Systemes’ curve and surface explicit geometry modeling tool. It is used to define, analyze, and perform high-end visualization of CAD surface models that feature complex free-form shapes. It ships with built-in QA and QC capabilities, helping designers to meet the highest level of quality.
Q-Checker
Q-Checker is designed for Dassault Systemes 3DExperience, helping designers control the quality of their designs and models on CATIA V4, V5, and V6. Q-Checker supports designers by identifying inefficiencies in the design process and common mistakes. It, therefore, helps users to conform to specific CAD standards. Moreover, it enforces internal CATIA standards, ensuring adherence to company design standards and specifications. Put simply, it supports higher product quality.
CAD Standards Manager
CAD Standards Manager for AutoCAD lets you configure the software with your preferred CAD standards. It allows you to set up a standards template that enables you to check and apply the standards to noncompliant drawings. In addition, the template enables AutoCAD to convert drawings sent by third parties to your preferred standards. In addition to setting up the standards template, CAD Standards Manager allows you to add layers, text styles, linetypes, multileaders, and dimensions to the standards template.
Challenges in Implementing CAD Quality Assurance
1. Budget Constraints
CAD software can be expensive. Unfortunately, the cost increases further when third-party QC/QA tools are procured. Additionally, to conduct full independent design checking, companies have to pay for the services of external professionals. These compounding challenges may block smaller companies from implementing quality assurance in CAD.
2. Software Limitations
CAD software applications may not always have all the requisite QA/QC capabilities. They may lack certain tools, preventing designers from completing thorough quality checks. To get around this problem, designers can use third-party solutions. However, this intervention may increase the cost of the project.
Companies can also adopt newer software, but this presents additional challenges. For instance, employees may be resistant to the changes. Additionally, the company has to enroll employees in training programs to learn how to integrate the new software into their workflow. This can be an expensive and time-consuming exercise. But perhaps more worryingly, the migration from one software to another can birth data compatibility and data loss issues, which are a tad harder to solve.
3. Inadequate Skills
The success of quality assurance in CAD is only possible if personnel have adequate skills to check for compliance, identify errors, or assure quality. Thus, a company or team whose personnel have inadequate skills and training to administer quality checks and quality control usually suffers quality issues and non-compliance. Fortunately, this challenge is easy to solve through training.
4. False Positives and Negatives
Earlier in this article, we discussed how designers can use AI-powered CAD solutions to identify and correct errors. However, AI models are only as effective as the data used to train them. In this regard, ineffective models may flag errors that, upon closer scrutiny, are not errors in design. The opposite can also be true, leading to instances where the models do not flag actual errors.
Conclusion
Implementing quality assurance in CAD is instrumental to ensuring the precision of CAD designs. It safeguards quality by promoting compliance with regulatory and CAD standards and identifying and correcting errors and mistakes. However, for the implementation to be successful, professionals must define and use a quality assurance program. Moreover, they must consistently perform quality checks and quality control activities. While this can sound daunting – and it is, particularly when implemented manually – technology can help simplify the processes. Today, AI-powered QA solutions, QMS software, and optimization, analysis, and tolerancing tools can help design professionals implement quality assurance in CAD. That said, the implementation is not without its challenges. These include inadequate skills, software limitations, false positives and negatives, and budget constraints. Nonetheless, these challenges are not insurmountable.
