Assembly FMEA: A Simplified Method for Identifying Assembly Errors

2003 ◽  
Author(s):  
Steven Kmenta ◽  
Brent Cheldelin ◽  
Kosuke Ishii
Keyword(s):  
Artificial Intelligence ◽  
Failure Modes ◽  
Electronic Circuits ◽  
Manual Assembly ◽  
Manufacturing Defects ◽  
Novel Technique ◽  
Analysis Process ◽  
Simplified Method ◽  
Process Failure ◽  
Assembly Defect

Manual assembly errors are a significant source of manufacturing defects. Therefore, an efficient method is needed to identify and alleviate potential assembly defects. Process Failure Modes and Effects Analysis (Process FMEA) is one technique used to anticipate, evaluate, and resolve potential manufacturing and assembly issues. However, performing FMEA is widely considered to be tedious and time-consuming, and not always worth the effort. In response, many researchers have attempted to automate FMEA using Artificial Intelligence (AI) to make it less arduous. Unfortunately, automated techniques are limited to systems with predictable behaviors (e.g., electronic circuits) and are rarely used on unpredictable processes such as manual assembly. “Assembly FMEA” is a novel technique developed specifically to identify manual assembly errors. Assembly defect levels are related to assembly complexity, which can be estimated using “Design for Assembly” (DFA) time penalties. Hence, Assembly FMEA uses a series of DFA-related questions to elicit potential assembly defects. The questions help to focus, standardize, and expedite the FMEA process. Assembly FMEA quickly identifies a large number of assembly errors with significantly less effort than conventional FMEA. This paper describes the Assembly FMEA procedure and illustrates its use on a conceptual design and on an existing product.

AI technologies and their impact on supply chain resilience during COVID-19

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sachin Modgil ◽  
Shivam Gupta ◽  
Rébecca Stekelorum ◽  
Issam Laguir
Keyword(s):  
Artificial Intelligence ◽  
Supply Chain ◽  
Information Processing ◽  
Supply Chains ◽  
Failure Modes ◽  
Stress Test ◽  
Weak Links ◽  
Content Type ◽  
Supply Chain Resilience

PurposeCOVID-19 has pushed many supply chains to re-think and strengthen their resilience and how it can help organisations survive in difficult times. Considering the availability of data and the huge number of supply chains that had their weak links exposed during COVID-19, the objective of the study is to employ artificial intelligence to develop supply chain resilience to withstand extreme disruptions such as COVID-19.Design/methodology/approachWe adopted a qualitative approach for interviewing respondents using a semi-structured interview schedule through the lens of organisational information processing theory. A total of 31 respondents from the supply chain and information systems field shared their views on employing artificial intelligence (AI) for supply chain resilience during COVID-19. We used a process of open, axial and selective coding to extract interrelated themes and proposals that resulted in the establishment of our framework.FindingsAn AI-facilitated supply chain helps systematically develop resilience in its structure and network. Resilient supply chains in dynamic settings and during extreme disruption scenarios are capable of recognising (sensing risks, degree of localisation, failure modes and data trends), analysing (what-if scenarios, realistic customer demand, stress test simulation and constraints), reconfiguring (automation, re-alignment of a network, tracking effort, physical security threats and control) and activating (establishing operating rules, contingency management, managing demand volatility and mitigating supply chain shock) operations quickly.Research limitations/implicationsAs the present research was conducted through semi-structured qualitative interviews to understand the role of AI in supply chain resilience during COVID-19, the respondents may have an inclination towards a specific role of AI due to their limited exposure.Practical implicationsSupply chain managers can utilise data to embed the required degree of resilience in their supply chains by considering the proposed framework elements and phases.Originality/valueThe present research contributes a framework that presents a four-phased, structured and systematic platform considering the required information processing capabilities to recognise, analyse, reconfigure and activate phases to ensure supply chain resilience.

scholarly journals A Factory Analysis on the Proportion of Defects Reduction in The Animal Feed Pellet Production Process using Design of Experiment Analysis

2019 ◽  
Vol 3 (2) ◽  
pp. 26-33
Author(s):  
Keyword(s):  
Production Process ◽  
Failure Modes ◽  
Animal Feed ◽  
Fractional Factorial ◽  
Pareto Chart ◽  
Manufacturing Defects ◽  
Root Cause ◽  
Pellet Production ◽  
Feed Pellet

The aim of this research is to reduce a number of defects during a feed pellet production process to improve customer satisfaction. A factory case study produces the feed pellets for several species such as food for pigs, chickens, and ducks. Production data from January to June 2017 manufacturing found that the manufacturing defects rate were about 3.32%. The data showed that the overall defects originated from different problems; 1) cracked or broken food; 2) high humidity; 3) distorted of product color; and 4) an ingredient error, respectively. Statistical methods, design analysis, and cause analysis techniques e.g. the Ishikawa diagram, Pareto chart, and FMEA (Failure Mode and Effects Analysis) were applied to help the factory to identify the main root cause of the defects and the potential failure modes of the factory case study. Due to an increasing number of complaints, this study only concentrated on the duck feed pellet production process. The study was divided into two parts: finding the root cause of the defects, which are the most critical factors for further analysis, and applying an experimental statistical design to decrease the number of defects during the duck pellet production process. The problem with cracked or broken pellets (dust) was found as the main factor affecting the production defects. Results showed that the main factors contributing to the amount of dusk in the duck feed productions came from three factors as follow: the thickness of die, distance between compression rollers and die, and time and temperature of mill machine needed during compressing the duck feed pellet production. Both the fractional factorial experimental design, 2k and 3k, were used to evaluate the influence of each factor on the duck feed production defects. The results by using the factorial 2K experimental show that the most important variable in duck pellets production were thickness of the die, distance between compression rollers and die, and temperature of mill machine needed during compressing the duck feed pellet production while time was not an interaction effect in this problem. The 3k factorial design was used to determine the interaction effects for the duck pellets production process. The experiment was ran and tested for 3 months. The final outcomes showed a significant reduction of defects from 2.51% to 1.09% (P<0.01). The results indicated that thickness -20 mm. of the die, 0.05 mm of distance between compression rollers and die, and 95 degree Celsius of temperature of mill machine needed during compressing the duck feed pellet production would be the most appropriate set of pelleting machine for the duck production process case study.

Mechanical Characterization of Metal Additively Manufactured Contact Aided Cellular Compliant Mechanisms

2021 ◽  
Author(s):  
Jivtesh B. Khurana ◽  
Mary Frecker
Keyword(s):  
Failure Modes ◽  
Mechanical Response ◽  
Compliant Mechanisms ◽  
Compliant Mechanism ◽  
Mechanical Test ◽  
Single Cells ◽  
Compression Testing ◽  
Balance Performance ◽  
Manufacturing Defects ◽  
Lattice Design

Abstract Additive manufacturing allows for the creation of complex geometries that can be optimized for performance. However, understanding the effect of the manufacturing process on part performance is essential to balance performance with manufacturability. In this work, a cellular contact aided compliant mechanism previously designed by the authors is manufactured using laser powder bed fusion. Failure modes for C3M lattice design are highlighted and recommendations for manufacturability are obtained. The mechanical response of C3Ms is characterized through compression testing of lattice and single cells. Compression testing is used to understand the mode of energy absorption of C3M lattices and compare with mechanical simulations. Lattices with large wall thickness and largest cell size are found to absorb the most strain energy. The increase in stiffness of the C3M lattice is found to depend on the thickness of the cell walls and size of the contact gap. The failure modes based on manufacturing and mechanical test data are synthesized to generate design rules for selecting C3M geometry to minimize manufacturing defects and maximize performance.

Reverse Fishbone Diagram: A Tool in Aid of Design for Product Retirement

1996 ◽  
Author(s):  
Kosuke Ishii ◽  
Burton H. Lee
Keyword(s):  
Failure Modes ◽  
Graphical Representation ◽  
Environmentally Conscious ◽  
The Past ◽  
Advanced Planning ◽  
Process Failure ◽  
Fishbone Diagram ◽  
Useful Life ◽  
Definition Of ◽  
Central Tool

Abstract This paper describes a schematic representation of product retirement specification that aids in design for recycling and reuse. In the past decade, a graphical representation of the assembly process, called the assembly fishbone diagram, has effectively assisted engineers to conduct design for assembly (DFA) and process failure modes and effects analysis (FMEA). On the other hand, environmentally conscious manufacturing requires engineers to make advanced planning for product retirement. This study investigates the use of the reverse fishbone diagram to model the disassembly and reprocessing sequence of a product at the end of its useful life. An industry-provided student project guided us to an initial definition of the reverse fishbone diagram that effectively led the students to analyze the recyclability and make practical redesign suggestions. The diagram is continuously adding more rigorous definitions and promises to be a central tool for evaluation of recyclability in a simultaneous engineering setting.

scholarly journals A Simplified Method for the Design of Steel Beam-to-column Connections

2017 ◽  
Vol 48 (2) ◽  
pp. 79-86
Author(s):  
Imola Kristóf ◽  
Zsanett Novák ◽  
Dezső Hegyi
Keyword(s):  
Failure Modes ◽  
Steel Structures ◽  
Simple Calculation ◽  
Geometric Parameters ◽  
End Plate ◽  
Simplified Method ◽  
Eurocode 3 ◽  
Steel Sections ◽  
The Moment ◽  
Hot Rolled

The moment resistance of beam-to-column connections is frequently utilised in steel structures. Eurocode 3 suggests the component method to analyse such connections, and it implements the equivalent T-stub method to determine the resistance of the end plate of the beam. The latter method requires tedious and concentrated work. A simplified method is suggested to reduce the number of calculations and enable the designer to focus on construction aspects in the pre-design phase, or in education.The resistance of the T-stub covers three possible failure modes: the yield of the plate, the failure of the of the bolt and simultaneous yield. The yield of the plate and simultaneous yield depend on numerous parameters, and they are verified by multiple equations. The failure of the bolts are more easily checked.In the present paper, requirements for geometric ratios are defined for the widely used steel sections to assure failure of the bolts at a lower level of the load than the yield of the plate. These parameters facilitate the simple calculation of the resistance of the bolts instead of the tedious work needed for the end plate resistance.The paper presents a proper explanation for the design rules and the effect of the geometric parameters on the resistance of the end plate. Geometric parameters are suggested for the widely used hot rolled and typical welded beam sections. All the parameters fulfil the requirements of the equivalent T-stub method of Eurocode 3.

Thermal–Hydraulic Performance Analysis for AP1000 Passive Containment Cooling System

2013 ◽  
Author(s):  
Yu Yu ◽  
Shengfei Wang ◽  
Fenglei Niu
Keyword(s):  
System Reliability ◽  
Nuclear Power ◽  
Failure Modes ◽  
Cooling System ◽  
Natural Circulation ◽  
Hydraulic Performance ◽  
Reactor Power ◽  
Physical Parameters ◽  
Cold Source ◽  
Process Failure

In order to improve the safety of new generation nuclear power plant, passive containment cooling system is innovatively used in AP1000 reactor design. However, since the system operation is based on natural circulation, physical process failure — natural circulation cannot establish or be maintained — becomes one of the important failure modes. Uncertainties in the physical parameters such as heat and cold source temperature and in the structure parameters have important effect on the system reliability. In this paper, thermal–hydraulic model is established for passive containment cooling system in AP1000 and the thermal–hydraulic performance is studied, the effect of factors such as air temperature and reactor power on the system reliability are analyzed.

Simplified Method of Calculating Assembly Time

2002 ◽  
Author(s):  
Zbigniew Prusak
Keyword(s):  
Consumer Goods ◽  
Initial Assessment ◽  
Functional Evaluation ◽  
Simple Method ◽  
Manual Assembly ◽  
Design Review ◽  
Assembly Time ◽  
Factors Influencing ◽  
Wide Range ◽  
Simplified Method

This paper presents a simplified method for functional evaluation of parts and subsequent combination and elimination of parts with redundant and unnecessary functions. The method uses a simple spreadsheet-based tool that has proven to be an effective aid during design review and brainstorming sessions. Also presented is a simple method of initial assessment of manual assembly times. The assessment is performed by taking into account basic factors influencing part recognition, handling, manual assembly workspace and putting the parts together. Usefulness of both tools has been initially tested on a wide range of assembly configurations, from a variety of simple consumer goods to aerospace components. Both tools can also be presented as checklists thus having a ready-to-use cookbook appearance, which was particularly valued by manufacturing engineers making quick on-the-floor assessments.

Challenges and Methods in the Quantification of Design Errors and Solution Elements

2004 ◽  
Author(s):  
Lawrence P. Chao ◽  
Kosuke Ishii
Keyword(s):  
Design Process ◽  
Life Cycle Cost ◽  
Quality Function Deployment ◽  
Failure Modes ◽  
Spatial Distance ◽  
Risk Priority Number ◽  
Design Elements ◽  
Process Failure ◽  
Temporal And Spatial ◽  
Process Level

To error-proof the design process, tools such as Design Process Failure Modes and Effects Analysis and Project Quality Function Deployment mitigate risk through thorough understanding of the consequences of both the process-level errors that can occur and the solution elements that mitigate them. However, the quantification of design errors and prioritization of other elements are complicated by the temporal and spatial distance of the decisions from the end-result. This paper discusses measures for design elements in the context of process-based analysis, including the design errors, tasks, and project resources. The Risk Priority Number is the standard measure of criticality of failure modes and their effects. However, alternatives to the traditional RPN have emerged in forms such as expected and life-cycle cost as well as QFD-based techniques. The paper explores the benefits and challenges of these traditional and new measures and concludes with a discussion into converting between the measures.

Sign in / Sign up

Export Citation Format

Share Document