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This paper results from research carried out to survey the various large commercial aerospace engineering component measurement systems. The commercial aircraft manufacturing industry is special due to the size of the components involved. Accuracy constraints remain very close, despite the size, and therefore accurate methods of measurement are necessary to control the quality of the final product. A survey of various current methods of measurement for such components is presented. These methods are based around three main principles: theodolites, photogrammetry, and laser technology. Each method has its own advantages and disadvantages in terms of accuracy, repeatability, range and cost. It is also often necessary to consider what each technique provides in terms of data storage and analysis. Most techniques use computer‐based systems to store results and perform various calculations. These systems also have their own requirements in terms of the environment in which they are used. It is important to consider whether a particular system can be installed in an area suitable to measure the required component, as well as ensuring that the stability requirements are met. In this paper the principles and characteristics of conventional optical tooling, electronic triangulation, electronic trilateration, photogrammetry, laser trackers, and laser scanners are reviewed.

The purpose of this paper is to identify control systems that give rise to better construction project performance; and develop and test project performance predictive models based on control systems adopted in the project.

Research design was questionnaire survey. Data were collected via Electronic mails. The sampling frame was Singapore-based construction firms.

In all, 16 control mechanisms are significantly correlated with project outcomes. The more important control mechanisms are: adequacy of project information to develop the project schedule; adequacy of float in the schedule; and quality of techniques used to support risk identification. Two relatively robust predictive models were constructed and validated to predict schedule and quality outcomes of construction projects. Schedule performance may be predicted by adequacy of float and stringency of criteria to select suppliers. Quality outcome is most significantly affected by competency of quality manager, rather than the hard systems adopted in the project.

The limitations include low response rate, and subjective nature of the five-point Likert scale used to rate project outcomes and extent to which control mechanisms were adopted in the project.

The implication of the findings is that merely having good project management practices and adequate resources are not sufficient to achieve good project outcomes. Instead, construction projects need to have control systems in place, as they play an important role in project outcomes.

The paper has shown empirically that control systems affect project outcomes. They are needed not just to control the project, but also help the project to achieve good outcomes. The research designed and tested two relatively robust models to predict schedule and quality outcomes of a project. These models may be used to make an initial assessment of the project's likely outcome, based on the control systems that contractors are going to adopt.

Posture adjustment plays an important role in spacecraft manufacturing. The traditional posture adjustment method, which has a large workload and is difficult to guarantee the quality of posture adjustment, cannot meet the requirements of modern spacecraft manufacturing. This paper aims to optimize the trajectory of posture adjustment, reduce the internal force of the posture adjustment mechanism and improve the accuracy of the system.

First, the measuring point is measured by a laser tracker and the position and posture of the cabin is solved. Then, Newton–Euler method is used to construct the dynamic model of the posture adjustment system (PAS) without internal force. Finally, the adjustment time is optimized based on Fibonacci search method and the trajectory of the cabin is fitted by the fifth order polynomial.

The simulation results show that, compared with the other trajectory planning methods, this method can effectively avoid the internal force of posture adjustment caused by redundant driving, and the trajectory of velocity and acceleration obtained are continuous, meeting the engineering constraints.

In this paper, a dynamic model of PAS without internal force is constructed. The trajectory planning of posture adjustment based on this model can improve the quality of cabin assembly.

This paper aims to present a method for predicting dimensional variation in assembly processes of a wingbox structure concentrating on the assembly of skin panels to rib feet.

Finite element modelling and experimental tests are conducted on the rib structure based on the site measurement gathered from the Airbus assembly factory.

The results have shown that the simulated model has the capability of predicting to an acceptable degree of accuracy the overall geometrical variations of the ribs and skin panels, as well as the positional variations of each individual rib foot.

The authors believe that no previous research has offered a similar prediction method for large aerostructures.

The pivotal aspect of aircraft assembly lies in precise measurement accuracy. While a solitary digital measuring tool suffices for analytical and small surfaces, it falls short for extensive synthetic surfaces like aircraft fuselage panels and wing spars. The purpose of this study is to develop a “combined measurement method” (CMM) that enhances measurement quality and expands the evaluative scope, addressing the limitations posed by singular digital devices in meeting measurement requirements across various aircraft components.

The study illustrated the utilization of the CMM by combining a laser tracker and a portable arm-measuring machine. This innovative approach is tailored to address the intricate nature and substantial dimensions of aircraft fuselage panels. The portable arm-measuring machine performs precise scans of panel components, while common points recorded by the laser tracker undergo coordinate conversion to reconstruct the fuselage panel’s shape. The research outlines the CMM’s measurement procedure and scrutinizes the data processing technique. Ultimately, the investigation yields a deviation vector matrix and chromatogram deviation distribution, pivotal in achieving enhanced measurement precision for the novel CMM device.

The use of CMM noticeably enhances fuselage panel assembly accuracy, concurrently reducing assembly time and enhancing efficiency compared to conventional measurement systems.

The research’s practical implication lies in revolutionizing aircraft assembly by mitigating accuracy issues through the innovative digital CMM for aircraft synthetic structure type product (aircraft fuselage panel). This ensures safer flights, reduces rework and enhances overall efficiency in the aerospace industry.

Introducing a new aircraft assembly accuracy compensation method through digital combined measurement, pioneering improved assembly precision. Also, it enhances aerospace assembly quality, safety and efficiency, offering innovative insights for optimized aviation manufacturing processes.

The purpose of this study is to explore the psychosocial aspects of palliative care provision for incarcerated persons drawing on a human rights perspective.

Seven databases were searched to identify empirical studies published from 2010 to 2020. Articles included were qualitative, quantitative, mixed methods, written in English and with westernised health/prison settings, with a key focus on the psychosocial aspects of palliative care provision and human rights. The quality of the articles was appraised using the Mixed Methods Assessment Tool (2018).

The results from 26 articles revealed multiple models of care, with the US prison hospice program depicted as optimal, because of the use of trained incarcerated caregivers, working as aides to the interprofessional team. The bereavement needs of caregivers were highlighted. The barriers to adequate psychosocial care were negative public discourse, prison processes and resources, provider attitudes and the incarcerated person’s level of knowledge and trust. Identified facilitators were related to incarcerated persons’ caregiving programs, a sense of purpose and visitation leniency. Human rights principles were identified in studies that featured compassionate release and advance care planning.

There is inconsistency in the literature regarding what constitutes psychosocial care, which meant that the authors needed to draw on multiple literature sources to formulate a definition. Additionally, the review only included studies written in English, meaning some high-quality studies could have been missed. The articles that conducted interviews with incarcerated individuals were undertaken in male prisons only and not female prisons.

Understanding the importance of psychosocial care for incarcerated persons with a life-limiting illness requires a shift in negative public discourse and the need for a stronger human rights focus. Some countries, such as the USA and UK, are achieving effective outcomes; however, countries such as Australia are yet to contribute to this knowledge base.

If palliative care is a human right, then its philosophy should be considered in its entirety, with the inclusion of psychosocial care.

For the automatic drilling and riveting in panel assembly, gaps between the skin and strangers are inevitable and undesirable. At present, the determination of pre-joining schemes relies on workers’ experience, introducing excessive number and inappropriate locations of pre-joining. This paper aims to present a new method for the evaluation of residual clearances after pre-joining and the pre-joining scheme optimization, providing operation guidance for the workers in panel assembly workshop.

In this paper, an equivalent gap assembly model for pre-joining is proposed on the basis of the mechanism of variation. This model retains the essential elastic behavior of the key features during the pre-joining operation and calculates the residual clearances in the view of the potential energy. Subsequently, this method is embedded into a Pareto optimality-based genetic algorithm, and the optimal pre-joining schemes are achieved with the consideration of the total residual clearances and the permissive tolerances.

The equivalent gap assembly model has the capability to predict an acceptable degree of accuracy of the residual clearances and achieve the optimized pre-joining schemes with less number of pre-joining at the same level of residual clearances.

The optimized pre-joining schemes are given in the form of Pareto optimality set, and workers can select suitable results according to their inclination to the quality and efficiency.

The paper is the first to propose the equivalent gap assembly model for the pre-joining operation, which provides for the simplification of the calculation of residual clearances based on the constrained variation principles.

In aircraft wing–fuselage assembly, the distributed multi-point support layout of positioners causes fuselage to deform under gravity load, leading to assembly difficulty and assembly stress. This paper aims to propose a hybrid force position control method to balance aerodynamic shape accuracy and deformation of assembly area, thereby correcting assembly deformation and reducing assembly stress.

Force and position control axes of positioners are selected based on screw theory and ellipsoid method. The position-control axes follow the posture trajectory to align the fuselage posture. To exert force on the fuselage and correct the deformations, the force-control axes follow the contact force derived by using orthogonal experiments and partial least squares regression (PLSR). Finite element simulation and one-dimension deformation correction experiment are conducted to verify the validity of this method.

Simulation results indicate that hybrid force position control method can correct assembly deformation and improve the wing–fuselage assembly quality significantly. Experiment on specimen verifies the effect of this method indirectly.

The proposed method gives a solution to solve the deformation problem during aircraft wing-fuselage assembly, thereby reducing assembly stress and improving assembly quality.

The edge is a typical aero-structural compliant part, whose length-width ratio is about 60:1 and height-thickness ratio is about 30:1. Distortion of the edge is mainly caused by the bulk stresses which come from the manufacturing process of the plates. This paper aims to investigate the effect of clamping sequence on the bulk stress distribution in the edge.

The paper conducts the numerical and experimental investigations to predict the bulk stress distribution in the edge under different clamping sequences. A finite element model of the plate with residual stress after quenching and stretching is constructed. The edge is milled from the plate numerically and is ready for clamping. The contact model between the clamper and the edge is constructed to simulate the clamping process. Then the edge is virtually clamped in different clamping sequences, and different deformations and bulk stresses are obtained. An experimental edge milled from the plate and a designed clamping platform are used to precisely control clamping force to verify the effect of clamping sequence on the bulk stress distribution in the edge. The experimental edge’s distortions, relative displacements between the edge and the clamper and clamping forces validate the proposed numerical model.

The primary cause of bulk stress redistribution is the friction between the rigid clamper and the compliant edge. The edge exhibits different deformation under different clamping sequences because of its compliant characteristics.

The proposed numerical model of the edge could predict the bulk stress distribution in the edge under different clamping sequence. The developed clamping platform could be used to conduct clamping experiments, including experiments with different clamping forces, sequences and different clamping positions. It will help to systematically improve the compliant assembling efficiency in civil aircraft industry.