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Electrical defects cover an important part of assembly defects and strongly affect the vehicle system performance. Almost 40% of assembly defects are classified as human errors and electrical connection failures represent a significant part of them. Humans still remain a cost-effective solution for the flexible manufacturing systems with increasing product complexity. So, understanding human behaviors is still a challenging task. The purpose of this study is to define, prioritize and validate the critical factors for the complexity of electrical connector plugin process.

The critical variables were defined by the expert team members. The required number of measurements and variables were revised resulting preliminary analysis of binary logistic regression. After the revision of measurement plan, the list of critical input variables and the mathematical model were defined. The model has been validated by the fitted values of the residuals (FITS analysis).

To the best of the authors’ knowledge, this is one of the limited studies, which defines the critical factors for electrical connection process complexity. Female connector harness length, connector width/height/length differences, operator sense of correct connector matching and ergonomy were defined as the factors with the highest impact on the failure occurrence. The obtained regression equation strongly correlates the failure probability.

The obtained mathematical model can be used in new model development processes both for the product and assembly process design (ergonomy, accessibility and lay-out).

The obtained risk factors demonstrated a strong correlation with assembly process complexity and failure rates. The output of this study would be used as an important guide for process (assembly line ergonomy, accessibility and lay-out) and product design in new model development and assembly ramp-up phases.

In the electrical industry 50 to 75% of the total production costs of a product are in assembly. This shows that the main focus for rationalisation should be in assembly. This paper illustrates planning methods for rationalisation, describes a completed assembly line and outlines the economies obtained.

The purpose of this paper is a study aimed at overcoming the interface issue between nanopaper and polymer matrix in shape-memory polymer (SMP) composite laminates caused by their large dissimilarity in electrical/thermal conductive properties. The study attempted to develop an effective approach to fabricate free-standing carbon nanofibre (CNF) assembly in octagon shape formation. The structure design and thermal conductive performance of the resulting octagon-shaped CNF assembly were optimised and simulated.

The CNF nanopaper was prepared based on a filtration method. The SMP nanocomposites were fabricated by incorporating these CNF assemblies with epoxy-based SMP resin by a resin-transfer modelling technique. Thermal conductivity of the octagon-shaped CNF assembly was simulated using the ANSYS FLUENT software for structure design and optimisation. The effect of the octagon-shaped CNF on the thermomechanical properties and thermally responsive shape-memory effect of the resulting SMP nanocomposites were characterised and interpreted.

The CNF template incorporated with SMP to achieve Joule heating triggered shape recovery at a low electric voltage of 3-10 V, due to which the electrical resistivity of SMP nanocomposites was significantly improved and lowered to 0.20 O·cm by the CNF template. It was found that the octagon CNF template with 2 mm width of skeleton presented a highest thermally conductive performance to transfer resistive heat to the SMP matrix.

A simple way for fabricating electro-activated SMP nanocomposites has been developed by using an octagon CNF template. Low electrical voltage actuation in SMP has been achieved.

The fabricated CNF template, the structure design and analysis of dynamic thermomechanical properties of SMP are novel.

The paper aims to describe the various moisture loads affecting conformal coatings. It also seeks to differentiate these from dewing. In the case of dewing, osmotic processes may trigger completely different chemical‐physical processes on the electronic assemblies.

Numerous test methods are available to verify the climatic resistances of conformal coatings. Focussing on moisture load and dewing, the different types of load are discussed and illustrated by means of examples.

The tests performed to ascertain the temperature and moisture load of conformal coatings show that under these high loads the electrical functional reliability is maintained. Thus, impacts of the individual process steps can be examined and assessed by means of moisture and insulation measurements.

Utilising different stress evaluations the described tests demonstrate the qualities of conformal coatings for electrical assemblies. Prospective tests for the purpose of lacquer and process qualification are presented.

The physical‐chemical load types with their consequences on conformal coatings for the protection of electrical assemblies are described.

Recent developments in microwave GaAs technology are yielding devices with higher power capabilities and increased levels of integration. The mechanical and thermal properties of GaAs and other microwave materials play a key role in the design and assembly of microwave power circuits. Thermal management is a critical element of microwave power circuit design. Thermal properties of microwave materials are discussed and compared with standard microelectronic materials. Material selection criteria are described. Assembly and packaging techniques also affect the overall performance of the GaAs power circuit. The high operating frequencies of microwave circuits make ordinary circuit elements, such as wire bonds and printed conductors, reactive. In addition, electrical performance criteria, such as high current or low impedance, create unique assembly demands. The successful development of a GaAs‐based microwave product is dependent on careful attention to the material properties and precise assembly methods. Techniques of automated assembly and processing are discussed, with ah eye towards maintaining high quality and reliability.

Analysis of test data monitored for a number of electric machines from the low volume production line can lead to useful conclusions. The purpose of this paper is to trace the machine performance to find quality-related issues and/or identify assembly process ones. In this paper, the monitoring of experimental data is related to the axial flux motor (AFM) used in hybrid electric vehicle (HEV) and in electric vehicle (EV) traction motors in the global automobile market.

Extensive data analyses raised questions like what could be the causes of possible performance deterioration of the AFM and how many electric motors may not pass requirements during operation tests. In small and medium research units of AFM for HEV or EV, engineers came across a number of serious issues that must be resolved. A number of issues can be eliminated by implementing methods for reducing the number of failing AFMs. For example, improving the motor assembly precision leads to reduction of the machine parameters deterioration.

Assembly tolerances on electric motor characteristics should be investigated during motor design. The presented measurements can be usable and can point out the weakest parts of the motor that can be a reason for the reduced efficiency and/or lifetime of the AFM. Additionally, the paper is addressed to electric motor engineers designing and/or investigating electric AFMs.

Performance of AFM was monitored for a number of identical motors from low volume production line. All tested motors were operated continuously for a long period of time and the tests were repeated every few weeks for half a year to check the reliability of motor design and indicate how much the motor parameters may change. The final results point how many motors fail the requirements of motor performance. A few batches of AFM were selected for testing. Each batch represents a different size (nominal power) of the same type of AFM.

The management of materials consists of an important analysis for industries as there are factors in several areas that should be considered. For this, it should take into account logistical factors, quality and production, because one piece delivered in a large lead time or outside the technical quality standards, imply delays in the project or rework. In this context, the importance of creating a control method of input and output of tools in an aviation industry in the city of Toulouse, France, was seen due to the amount of many incomplete arrivals or inappropriate material for use. The paper aims to discuss this issue.

This study used a philosophy of lean manufacturing tools and visual management (VM). A VM panel with information documents of all tools used in an assembly station of a model airplane was applied. With all data collected to carry out the project, the panel was created with the most relevant information of each tool and applied to an assembly station. That done, the production supervisors, mechanical and electrical supervisors were trained in the operation. Despite a change of management, it was realized that all supported the change due to the ease of understanding of the method and a good VM.

At the end of the work, materials management became more simplified, operators were more satisfied because of the non-occurrence of tools mistakes and the control time decreased from 120 to 15 minutes.

The application of this project has begun in an assembly station; however, it has been validated to be applied throughout the facility and its applications are being studied for other industries with different models.

This project developed a visual panel for support visual communication of the airplane assembly line. Its usage eliminates tools lost, inefficiencies and decreases lost time with tools selection.

This work proposes a way to simplify the management tools for assembly station plane using a VM panel based on the lean philosophy. The study was conducted at the Final Assembly Line of an aircraft model from a unit of an aircraft company.

To present and discuss open trace defects uncovered in an FR4 assembly during electrical testing.

This paper presents open trace defects observed in FR4 assemblies and analyses the distribution of defects. The paper also discusses possible root causes for their occurrence.

The open trace defects that occurred during printed circuit board (PCB) fabrication should have been observed by the board manufacturer. It appears that the PCB manufacturer did not perform automatic optical inspection (AOI) and electrical testing during the manufacturing of the boards. The cost due to the rejected PCBAs was approximately 3x times that of the PCB cost.

The paper highlights the costly impact of uncovering a PCB defect after assembly. Based on the results of this study, the implementation of electrical testing and AOI for PCBs is recommended.

The purpose of this paper is to report on various adhesives and their uses in the electronics industry.

A description of the different types of adhesives and their strengths and weaknesses is followed by illustrations of their applications in electronic and electrical assembly. Equipment and procedures for cleaning and surface preparation are presented, and the paper finishes with an examination of techniques for rework and repair.

Polymers form the body of an adhesive, but other elements may be included to control electrical and heat conduction, light absorption and cross‐bonding behaviour. This makes them highly controllable and adaptable to specialised requirements. Photo‐curable adhesives with cure times of under 1 s are available for fast‐throughput assembly. Polymer underfills are increasingly important for shock‐proofing handheld electronics. Adhesives and cleaning agents are becoming environmentally safer.

The paper reveals the versatility of polymer adhesives and names suppliers.

Additive manufacturing (AM) offers substantial flexibility in shape, but much less flexibility in materials and functionality – particularly at small size scales. A system for automatically incorporating microscale components would enable the fabrication of objects with more functionality. The purpose of this paper is to consider the potential of self‐assembly to serve as an automated programmable integration method. In particular, it addresses the ability of random self‐assembly processes to successfully assemble objects with high performance despite the possibility of assembly errors.

A self‐assembled thermoelectric system is taken as a sample system. The performance expectations for these systems are then predicted using modified one‐dimensional models that incorporate the effects of random errors. Monte‐Carlo simulation is used to predict the likely performance of self‐assembled thermoelectric systems and evaluate the impact of key process and system design parameters.

While assembly yield can drop quickly with increasing numbers of assembled parts, large functional assemblies can be constructed by arranging components in parallel to provide redundancy. In some cases, the performance losses are minimal. Alternatively, sensing can be incorporated to identify perfect assemblies. For small assemblies, the probability of perfection may be high enough to achieve an acceptable assembly rate. Small assemblies could then be combined into larger functional systems.

The paper identifies two strategies that can guide the development of AM processes that incorporate miniature components to increase the system functionality. The analysis shows that this may be possible despite significant errors in the self‐assembly process because systems may be tolerant of significant assembly errors.