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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.

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

This study aims to research the development trend, research status, research results and existing problems of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

Based on the investigation and analysis of the development history, structure form, structural parameters, stress characteristics, shear connector stress state, force transmission mechanism, and fatigue performance, aiming at the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge, the development trend, research status, research results and existing problems are expounded.

The shear-compression composite joint has become the main form in practice, featuring shortened length and simplified structure. The length of composite joints between 1.5 and 3.0 m has no significant effect on the stress and force transmission laws of the main girder. The reasonable thickness of the bearing plate is 40–70 mm. The calculation theory and simplified calculation formula of the overall bearing capacity, the nonuniformity and distribution laws of the shear connector, the force transferring ratio of steel and concrete components, the fatigue failure mechanism and structural parameters effects are the focus of the research study.

This study puts forward some suggestions and prospects for the structural design and theoretical research of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

The purpose of this paper is to propose a computational approach to establish the effect of various flow drilling screw (FS) process and material parameters on the quality and the mechanical performance of the resulting FS joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the FS process; (b) determination of the mechanical properties of the resulting FS joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the FS joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified FS connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all FS joints is associated with a prohibitive computational cost.

Virtual testing of the shell components fastened using the joint connectors validated the ability of these line elements to realistically account for the strength, ductility and toughness of the three-dimensional FS joints.

The approach developed in the present work can be used, within an engineering-optimization procedure, to adjust the FS process and material parameters (design variables) in order to obtain a desired combination of the FS-joint mechanical properties (objective function).

The reliability of an electronic connector is more important now than at any time in the past. Not only has system complexity grown but operating environmental conditions are more severe and system speed has made circuits less tolerant of any interference. With “fly by wire” aircraft, and fully computer controlled communications systems, even more demanding performance is required. However system reliability is calculated, whether by MIL‐HDBK‐217B, or latest S.A.E. data, or the more traditional MTBF calculations, it is clear that connections form a key part of the total statistics. As a greater number of components have become interconnected, either by rack, module, panel, backplane, or PCB, pin counts on connectors have slowly increased. A connector which only a few years ago would have 160 ways now has 220 or 330 ways. Finally, as component sizes shrink and on‐chip integration grows there is very significant pressure to reduce the size of connectors whilst at the same time further improving reliability.

The purpose of this paper is to present a supervised adaptation platform for applications‐based components.

The platform is designed using a model based top‐down approach. The authors use UML diagrams and particularly scenarios and activity diagrams.

The CSC (component, service and connector) platform is based on a component/service model that allows adaptation of component‐based applications and uses service‐oriented architecture for providing adaptation services to be embedded in adaptation connectors.

The paper proposes CSC, a self‐adaptation platform based on MMSA, to describe software architectures for multimedia‐oriented application and providing adaptation capabilities. The platform is based on services and offer architecture, with three layers particularly adapted to adaptation of multimedia flow (types, formats, properties) and which allows solving the heterogeneity problems of components.

A new “backshell to backshell” connector system, the DG 123, that significantly improves corrosion resistance, durability and electromagnetic (EMI) compatibility, while also offering weight savings of more than 30% in comparison with standard aluminium connectors, is now gaining considerable acceptance in new aircraft and avionic projects. Applications for this revolutionary approach to the design of circular connectors using “composite” materials and metalisation processes include weapon pylons on carrier borne aircraft — where the DG123 correction system has contributed to a significant improvement on the Mean Time Between Failure (M.T.B.F.) figure. The connectors are also used on missile systems and have recently been approved for use on the United States space station “Freedom”.

This paper aims to present a smooth transition adaptive hybrid impedance control for compliant connector assembly.

The dynamics of the manipulator is firstly presented with linear property. The controller used in connector assembly is inspired by human operation habits in similar tasks. The hybrid impedance control is adopted to apply force in the assembly direction and provide compliance in rest directions. The reference trajectory is implemented with an adaptive controller. Event-based switching strategy is conducted for a smooth transition from unconstrained to constrained space.

The method can ensure both ideal compliance behaviour with dynamic uncertainty and a smooth transition from unconstrained to constrained space. Also, the method can ensure compliant connector assembly with a good tolerance to the target estimation error.

The method can be applied in the connector assembly by “pushing” operation. The controller devotes efforts on force tracking and smooth transition, having potential applications in contact tasks in delicate environment.

As far as the authors know, the paper is original in providing a uniform controller for improving force and position control performance in both unconstrained and constrained space with dynamic uncertainty. The proposed controller can ensure a smooth transition by only adjusting parameters.

DESPITE having worked in the Aircraft Industry for many years, I had never considered the importance of connectors to the operational efficiency of aircraft. That is, until one dark night when I was driving back into London along the M4 motorway, in the centre lane, at a steady 70mph cruise, the engine suddenly stopped. I declutched, disengaged the gear and coasted on, looking for a gap in the nearside traffic to reach the hard shoulder. When I tried to signal left I realised I had suffered a total electrical failure. After a cold wait the AA man came to my rescue, pulled the loom of wires from the engine bulkhead, cleaned up the pins and replaced it. The engine, lights and indicators sprang back into life. I learned about connectors that night!

Gold coatings are used on connector structures to maintain suitable solderability of the underlying Ni coating layer as well as to prevent surface corrosion during service. However, the likelihood of Au embrittlement in connector solder joints must be minimized by eliminating much of the Au plating from the surfaces using a hot solder dipping or “wicking” procedure prior to final assembly. It was observed that Au removal was most effective by using a double wicking process. Also, a higher soldering temperature improved the efficiency of the Au removal process. A longer soldering time during the wicking process did not appear to offer an appreciable improvement in Au removal. Because the wicking procedure was a manual process, it was found to be operator dependent.