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This paper aims to address a need for improving the structural resilience to multi-hazard threats including fire and progressive collapse caused by the loss of a column.

The focus is on a steel moment frame that uses welded-unreinforced flange-bolted web connections between the beams and columns. A three-dimensional finite element (FE) model was created in ABAQUS with temperature-dependent properties for steel based on the Eurocode. The model was validated against experimental data at ambient and elevated temperature.

The failure mechanisms in the FE model were consistent with experimental observations. Two scenarios were considered: fixed load with increasing temperature (i.e. simulating column failure prior to fire) and fixed temperature with increasing load (i.e. simulating column failure during fire).

A macro element (or component-based) model was also introduced and validated against the FE model and the experimental data, offering the possibility of analyzing large-scale structural systems with reasonable accuracy and improved computational efficiency.

Only robot welding can give the quality and consistency of output demanded in welding the steel frame and aluminium alloy swing arm of the new range of Triumph motorcycles. Project engineer Ben Parry talks to Jack Hollingum.

This paper examines the level of detail and complexity that one needs to incorporate in a computational finite element (FE) model to predict the thermal and structural response of steel high-rise building frames to fire. Comparisons are made between these models in terms of accuracy and efficiency. Performance related to three parameters was examined: (1) the representation of the structural system as a 3-D full frame model versus a 2-D plane-frame model, both of which include the steel frame and the floor slab; (2) the representation of the slab in the 2-D plane frame model; and (3) the effects of modeling the temperature profile of each steel member cross-section as non-uniform (i.e. allowing a thermal gradient to develop) versus uniform. Results indicate that the 2-D plane frame model can be reasonably used in some cases to predict the performance of the perimeter column and floor beams framing into them in a fire-exposed high-rise moment-resisting frame (MRF) with a significant savings in analysis run time. The slab has little influence on the structural analysis of a 2-D plane frame; however, the slab influences the thermal profile through the depth of the beams, and these temperature changes will produce a non-negligible change when calculating the behavior of the frame and should be accounted for. Results also indicate that models whose members have uniform temperature can be used to obtain reasonable estimates of the interaction between connected beams and columns. However, thermal gradients produce significant changes in the deflection mechanics and plastic P-M limit state behavior exhibited by non-uniformly heated beam-columns that experience a severe decrease in capacity; therefore, it is recommended that thermal gradients be included in models that are used to predict deflections or plastic limit state behavior.

Outlines ABB Robotics new manufacturing philosophy of “lean robotization” based on early partnership between customer and supplier and a detailed knowledge of the customers application requirements. Examines two new ABB robots, suitable for a wide variety of functions, and operated by a new controller which uses a windows‐style user interface to simplify programming and process tuning. Describes some of the new features of the control which are claimed to bring major benefits in productivity and quality.

Smart materials (SMs) have the potential for facilitating active disassembly (AD). Select SMs are used in the design of devices to aid product disassembly. The purpose of this paper is to compare different AD approaches and highlight future work and potential.

This work is a survey of the collated AD research employing only Smart and “made Smart” materials work from various published work in the field from companies and academia since its original invention. The introduction gives general discussion of AD with cost implications and how the technology could offer very lean dismantling. An overview of the history of the work is given with the context of the implications for the need for a technology like AD to retain critical materials.

Besides a survey to date, comparisons were made of each AD technology application highlighting advantages and challenges. Comparisons were also made prior to this in alternative disassembly strategies to give context to the potential usefulness of the technology.

Only AD with SMs or “made Smart” were highlighted with some considerations for potential candidates.

A survey of AD work only employing SMs and “made‐Smart” materials to date. Comparisons of each AD application were made highlighting advantages and challenges. Comparisons were made between AD and alternative disassembly strategies to give context to the potential usefulness of the technology. The conclusion included an overview of work with consideration for future work. A candidate technology with the most potential was discussed.

This paper aims to propose a roadmap to control the robot–subassembly (R–S) coordination errors in movable robotic drilling. Fastener hole drilling for multi-station aircraft assembly demands a robotic drilling system with expanded working volume and high positioning accuracy. However, coordination errors often exist between the robot and the subassembly to be drilled because of disturbances.

Mechanical pre-locating and vision-based robot base frame calibration are consecutively implemented to achieve in-process robot relocation after station transfer. Thus, coordination errors induced by robotic platform movements, inconsistent thermal effects, etc. are eliminated. The two-dimensional (2D) vision system is applied to measure the remainder of the R–S coordination errors, which is used to enhance the positioning accuracy of the robot. Accurate estimation of measured positioning errors is of great significance for evaluating the positioning accuracy. For well estimation of the positioning errors with small samples, a bootstrap approach is put forward.

A roadmap for R–S coordination error control using a 2D vision system, composed of in-process relocation, coordination error measurement and drilled position correction, is developed for the movable robotic drilling.

The proposed roadmap has been integrated into a drilling system for the assembly of flight control surfaces of a transport aircraft in Aviation Industry Corporation of China. The position accuracy of the drilled fastener holes is well ensured.

A complete roadmap for controlling coordination errors and improving positioning accuracy is proposed, which makes the high accuracy and efficiency available in movable robotic drilling for aircraft manufacturing.

The purpose of this paper is to perform a comparative assessment on working of the existed subassembly identification (SI) methods, which are widely practiced during the product development stage and to propose an improved method for solving the SI problem in assembly sequence planning (ASP).

The cut-set method is found as a suitable method among various knowledge-based methods such as the theory of loops, theory of connectors and theory of clusters for the workability enhancement to meet the current requirements. Necessary product information is represented in the matrix format by replacing the traditional AND/OR graphs and the advanced predicates are included in the evaluation criteria.

The prominent methods in SI are followed a few of the predicates to avoid complexity in solution generation. The predicate consideration is found as the most influencing factor in eliminating the infeasible part combinations at SI. However, the quality of identified subassemblies without advanced predicates is not influencing the solution generation phase but practical applicability is affecting adversely.

The capability of performing SI by the cut-set method is improved to deal with the complex assembly configurations. The improved method is tested by applying on different assembly configurations and the effectiveness is compared with other existent methods of ASP along with the conventional method.

Quality control circles, a Japanese management technique for improving quality, productivity, and worker morale, have been widely adopted in western industry. The apparent hope is that the circles are a key to competing with the Japanese. In this article QC circles are shown to resemble, and potentially overlap with, six other western work improvement programmes, most of which have had successful histories. Case observations offer limited evidence that plant configuration considerations should be foremost among the factors emphasised in an industrial work improvement programme and that western industry should not expect too much from quality control circles.