Installation Tasks Research Articles

Trust in Artificial Intelligent Agent while Completing a Procedural Construction Task

The use of AI-enabled recommender systems in construction activities has the potential to improve worker performance and reduce errors; however, the accuracy of such systems in providing effective suggestions is dependent on the quality of their training data. A within-subjects experimental study was conducted using a simulated recommender system for installation tasks to investigate the effect of system reliability and construction task complexity on worker trust, workload, and performance. Results indicate that overall trust in the AI agent was higher for the highly reliable condition but remained consistent across various levels of task complexity. The workload was found to be higher for low reliability and complex conditions, and the effect of reliability on performance was influenced by task complexity. These findings offer insights for designing recommender systems to support construction workers in completing procedural tasks.

Automated Classification of the Phases Relevant to Work-Related Musculoskeletal Injury Risks in Residential Roof Shingle Installation Operations Using Machine Learning

Awkward kneeling in sloped shingle installation operations exposes roofers to knee musculoskeletal disorder (MSD) risks. To address the varying levels of risk associated with different phases of shingle installation, this research investigated utilizing machine learning to automatically classify seven distinct phases in a typical shingle installation task. The classification process relied on analyzing knee kinematics data and roof slope information. Nine participants were recruited and performed simulated shingle installation tasks while kneeling on a sloped wooden platform. The knee kinematics data were collected using an optical motion capture system. Three supervised machine learning classification methods (i.e., k-nearest neighbors (KNNs), decision tree (DT), and random forest (RF)) were selected for evaluation. The KNN classifier provided the best performance for overall accuracy. The results substantiated the feasibility of applying machine learning in classifying shingle installation phases from workers’ knee joint rotation and roof slope angles, which may help facilitate method and tool development for automated knee MSD risk surveillance and assessment among roofers.

Comparison of on-site and off-site robot solutions to the traditional framing and drywall installation tasks

Comparison of on-site and off-site robot solutions to the traditional framing and drywall installation tasks

A Signal Temporal Logic Motion Planner for Bird Diverter Installation Tasks With Multi-Robot Aerial Systems

A Signal Temporal Logic Motion Planner for Bird Diverter Installation Tasks With Multi-Robot Aerial Systems

What (specifically) differentiates the successful and unsuccessful systems delivery projects (SDPs)

PurposeAgainst the backdrop of management, planning, temporary organizations, Shannon–Weaver theory of communication and evaluation theories, the purpose of this research paper is to examine the relative importance of specific project management tasks in the various phases of system delivery projects in distinguishing successful and unsuccessful projects.Design/methodology/approachA survey method was used (N = 3,129) to collect data from the customers of a major systems delivery project management company operating in the facilities management industry. Logistic regression was used to analyze the capability and relative importance of the tasks in discriminating successful and unsuccessful projects.FindingsThe results of the paper indicate that three out four installation tasks were among the top three in their ability to differentiate the successful and unsuccessful systems delivery project. Especially critical tasks were “Meeting milestones” and “Allocation of appropriate resources” so that the project could be completed on-time. Relatively less important tasks were “Advice and suggestions regarding the development of specifications for the project” and “Proposal to meet the intent of the company’s specifications” in the proposal phase of the project, and “Resolving warranty issues as defined by the warranty process” in the commissioning phase.Originality/valuePrevious research has assessed the importance of the various project management phases. This research examines the capability of the more minutiae tasks to distinguish the successful and unsuccessful projects in the various phases of systems delivery projects, i.e. proposal, installation and commissioning.

PERANCANGAN JARINGAN KOMPUTER RT/RW NET MENGGUNAKAN JALUR KOMUNIKASI POWER LINE (PLC) DI PERUMAHAN TAMAN BERDIKARI SENTOSA

RT/RW Net is a non-governmental computer network within the scope of RT/RW. Building an RT/RW Net in the Taman Berdikari Sentosa housing estate is a concept where several computers in a housing or block can be connected and can share data and information, express opinions, conduct polls, and even elect RT/RW. The RT/RW net network will be built using a power line (PLC) communication line. Power Line Communication (PLC) is a technology that supports computer networks on a small scale such as a LAN, RW/RW net, which can provide convenience in installation tasks to produce high-speed computer networks. In principle, the Powerline used functions as a medium that converts digital data to electric current so that the data can be sent via a power cable. Building an RT/RW Net network using Power Line is no different from building an RW/RW Net in general. The difference only lies in the data transmission media used, Power Line uses electric cables while RT/RW Net generally uses cables such as UTP, Fiber Optic, Coaxial, and wireless networks

Automated scheduling and control of mechanical and electrical works with BIM

Current planning tools provide insufficient support for the scheduling and control of Mechanical and Electrical works in construction projects. Consequently, installation activities often deviate from project plans. However, BIM data on the spatial layout of Mechanical and Electrical systems can be used for more detailed and accurate planning of their installation, and to identify points where work progress should be tracked. This paper presents a novel method for the automated scheduling and control of Mechanical and Electrical Works. A topological analysis of the precise position of components is used to define relationships between the installation tasks, and to identify the optimal schedule. The definition of specific control points supports effective progress tracking to ensure that tasks adhere in practice to this schedule.

Effects of a passive upper extremity exoskeleton for overhead tasks

Overhead work is a major cause of upper extremity work-related musculoskeletal disorders (WMSD). In this paper, the potential effects of a Passive Upper-Limb Exoskeleton (PULE) were evaluated in the tasks of overhead works. This proposed PULE has a higher degree of freedom and does not impede the user's upper limb movements. Fifteen male volunteers participated in the study by performing the repeated overhead bolt installation tasks. The electromyographic (EMG) values of anterior deltoid (AD), mid deltoid (MD), descending trapezius (TR), and triceps (TB) of the left and right arms of the participants were measured at three different overhead task heights with Intervention (with/without the PULE). Moreover, the rankings of perceived discomfort (RPD) obtained on the neck, shoulders, upper arms, forearms, upper back, waists, and legs were rated for each participant. The preliminary experiment results show that the initial nEMG of right anterior deltoid (AD) decreased by 38.5%, median nEMG values decreased by 45.1%, and total RPD decreased by 52.4%. The use of the PULE could bring the benefits of less upper extremity muscle contraction and lower RPD compared to the non-use, which may potentially reduce or slow down the level of upper extremity WMSD across the overhead work.

Effects of Wind-Wave Misalignment on a Wind Turbine Blade Mating Process: Impact Velocities, Blade Root Damages and Structural SafetyAssessment

Most wind turbine blades are assembled piece-by-piece onto the hub of a monopile-type offshore wind turbine using jack-up crane vessels. Despite the stable foundation of the lifting cranes, the mating process exhibits substantial relative responses amidst blade root and hub. These relative motions are combined effects of wave-induced monopile motions and wind-induced blade root motions, which can cause impact loads at the blade root’s guide pin in the course of alignment procedure. Environmental parameters including the wind-wave misalignments play an important role for the safety of the installation tasks and govern the impact scenarios. The present study investigates the effects of wind-wave misalignments on the blade root mating process on a monopile-type offshore wind turbine. The dynamic responses including the impact velocities between root and hub in selected wind-wave misalignment conditions are investigated using multibody simulations. Furthermore, based on a finite element study, different impact-induced failure modes at the blade root for sideways and head-on impact scenarios, developed due to wind-wave misalignment conditions, are investigated. Finally, based on extreme value analyses of critical responses, safe domain for the mating task under different wind-wave misalignments is compared. The results show that although misaligned wind-wave conditions develop substantial relative motions between root and hub, aligned wind-wave conditions induce largest impact velocities and develop critical failure modes at a relatively low threshold velocity of impact.

Compliant Bimanual Aerial Manipulation: Standard and Long Reach Configurations

The ability of aerial manipulation robots to reach and operate in high altitude workspaces may result of interest in a wide variety of applications and scenarios that nowadays cannot be accessed easily by human operators. Consider for example the installation of sensors in polluted areas, the insulation of leaks in pipe structures, or the corrosion repair in power lines and wind turbines. This paper describes the application of a human-like dual arm aerial manipulator for the inspection of pipe structures, typical of chemical plants, involving the installation and retrieval of sensor devices. The goal is to reduce the time, cost, and risk with respect to conventional solutions conducted by human workers. Two configurations of the aerial robot are considered and compared: the standard, in which the arms are installed at the base of the multirotor, and the long reach configuration in passive pendulum, which extends the effective workspace of the manipulator and increases safety during the operation on flight. The kinematic and dynamic models of both configurations are derived, proposing a unified notation for the equations of motion, and a force/position control scheme that relies on the servo controller and the mechanical joint compliance. The paper also describes a simulation framework used for validating the execution of the aerial manipulation task before the realization of the real experiments, which contributes to reducing the probability of failure. The potential application of the standard and long reach configurations is evaluated in two sensor installation tasks carried out in an indoor testbed.

Impacts of Using Passive Back Assist and Shoulder Assist Exoskeletons in a Wholesale and Retail Trade Sector Environment

OCCUPATIONAL APPLICATIONSPassive back-assist exoskeletons (BAEs) and a passive shoulder-assist exoskeleton (SAE) were field tested among 14 workers who perform stocking and tire installation tasks. Heart rate (HR) and step rate were collected from eight workers both with and without exoskeleton use, and subjective feedback was obtained from all 14 workers who used the devices for one full work shift. For workers who used the SuitX™ BackX, mean HR increased 6.8% while mean step rate was reduced by 17.4% compared to without the device. For workers who used the Levitate™ AIRFRAME, mean HR decreased by 3.4% and mean step rate was reduced by 20.5% compared to without the device. Workers reported perceived benefits and a willingness to use an exoskeleton for at least part of their shift. However, they also indicated concerns about movement quality, task performance, and comfort. These results call into question the potential for the occupational exoskeletons tested to prevent injury by reducing physiological fatigue, and suggest that there are still challenges to consider for tactical deployment to specific jobs, tasks, and workers in the Wholesale and Retail Trade Sector.

A comprehensive numerical investigation of the impact behaviour of an offshore wind turbine blade due to impact loads during installation

For installing offshore wind turbines into deep waters, use of floating crane vessels is essential. One of the major challenges is their sensitivity to wave-induced vessel and crane tip motions, which can cause the impact of lifted components like blades and nacelle with nearby structures. The impact loads on fibre composite wind turbine blades are critical as several complex damage modes, capable of affecting the structural integrity, are developed. Planning of such installation tasks therefore requires response-based operational limits that consider impact loads on the blade along with their damage quantification. The research area considering the impact behaviour of the lifted blade is novel, and thus, the paper identifies vessel, blade and lifting parameters that determine impact/contact scenarios. Furthermore, for a case in which a lifted blade with its leading edge impacts the tower, a numerical modelling technique is presented in Abaqus/Explicit, and a comprehensive damage assessment of the blade and an investigation of the impact dynamics and energy evolution are performed. Sensitivity studies for two distinct blade designs and two different impact locations are considered. The results show that 7–20% of the impact energy is absorbed as damage in the blade, whereas the majority dissipates as rigid-body motions of the blade after the impact. The findings of the study highlight the requirement for advanced installation equipment, such as active tugger lines, to prevent successive impacts of wind turbine blades during installation.

Impact assessment of a wind turbine blade root during an offshore mating process

Single-blade installation is a popular method for installing blades on bottom-fixed offshore wind turbines. A jack-up crane vessel is often employed, and individual blades with their roots equipped with mechanical joints and bolted connections are lifted to the tower-top height and mated with a pre-assembled hub. The final mating phase is challenging and faces significant risks of impact. Due to relative motions between the blade and the hub, substantial impact forces may arise and lead to severe structural damages at root connections, thereby causing delays in the installation task. The present paper considers a realistic scenario of the mating process and investigates the consequences of such impact loads. Here, a single-blade model with tugger lines and a monopile model were established using a multi-body formulation, and relative velocities under collinear wave and wind conditions were obtained. A three-dimensional finite element model was developed for the blade root with T-bolt connections, and an impact investigation was performed for the case in which a guiding connection impacts the hub. The results show severe bending and plastic deformation of the guide pin bolt together with failure of the adjoining composite laminate at the root connection. Based on the type of damage obtained for the different environmental conditions considered, this paper also discusses its consequence on the installation tasks and suggests onboard decision making in case of an impact incident. The results of this study provide new insights regarding the mating phase and can be utilised to establish response-based operational limits.

A Lean Approach for Real-Time Planning and Monitoring in Engineer-to-Order Construction Projects

Engineer-to-order (ETO) construction companies are characterized by an off-site and on-site production. Often, budget deviations for installation works on-site are identified in a late stage when improvement actions cannot be applied anymore. Consequently, installation tasks are often affected by significant delays and/or reworks. This work proposes a “real-time” capable approach for planning and monitoring in construction and a corresponding information technology (IT) framework. The core is represented by the so-called “pitching” concept known from lean management, which breaks down large job orders into smaller controllable parts. It can be considered as the main enabler for gathering management information in real-time and to identify problems and their causes on time. The most noticeable consequence lies in smaller jobs and a software-aided punctual control that allows a better rescheduling capability and, thus reduced, delays. A case study is provided, showing how the model was applied and validated in an ETO façade supplier company.

Robust simulation-based scheduling methodology to reduce the impact of manual installation tasks on low-volume aerospace production flows

This work focuses on the development, implementation, and evaluation of a robust simulation-based planning and optimization methodology. This methodology attempts to reduce the risk of schedule overruns by identifying plans that are robust to various process delays and disruptions. A representative case study is used to test the methodology's capability to model a real production environment and search for improved scheduling options. The case study involves planning manual sensor installation processes within a provided production schedule to reduce the impact of the sensor installations and the risk of production delays. Properly planning sensor installations is becoming more important as new aerospace vehicles continue to incorporate more sensors to monitor system health, performance, safety, reliability, etc.Traditional scheduling techniques provide a strong framework to plan and optimize, at a medium level of detail, the completion of primary production processes (e.g. structural assembly, system integration, etc.). However, fully defining the interactions and logic required to evaluate the impact resulting from the sensor installation tasks in this scheduling framework is challenging. The discrete-event simulation paradigm simplifies the definition of these production rules and constraints; however, DES models commonly require too much detail, modeling effort, and optimization time/resources to be useful during pre-production planning. The developed methodology addresses this challenge by integrating the process optimization strengths of scheduling with the modeling flexibility of simulation. This enables the fast generation of a limited fidelity simulation that can evaluate the impact of sensor installations to support simulation-based schedule optimization. Throughout this work, the methodology is built up by leveraging various scheduling, simulation, and optimization capabilities. The methodology is then implemented to explore its ability to model and optimize the case study's problem. Finally, results from optimization runs with and without considering schedule robustness are compared to investigate how the methodology utilizes information about schedule risk to improve the resulting plan.

Performance Evaluation of Experts Predicting the Delay Factors and the Delay Time of the Nozzle Dam Installation and Removal Tasks

Performance Evaluation of Experts Predicting the Delay Factors and the Delay Time of the Nozzle Dam Installation and Removal Tasks

Managerial Factors Influencing Dose Reduction of the Nozzle Dam Installation and Removal Tasks Inside a Steam Generator Water Chamber

Managerial Factors Influencing Dose Reduction of the Nozzle Dam Installation and Removal Tasks Inside a Steam Generator Water Chamber

Applying Design for Assembly Principles in Computer Aided Design to Make Small Changes that Improve the Efficiency of Manual Aircraft Systems Installations

The installation of essential systems into aircraft wings involves numerous labour-intensive processes. Many human operators are required to perform complex manual tasks over long periods of time in very challenging physical positions due to the limited access and confined space. This level of human activity in poor ergonomic conditions directly impacts on speed and quality of production but also, in the longer term, can cause costly human resource problems from operators' cumulative development of musculoskeletal injuries. These problems are exacerbated in areas of the wing which house multiple systems components because the volume of manual work and number of operators is higher but the available space is reduced.To improve the efficiency of manual work processes which cannot yet be automated we therefore need to consider how we might redesign systems installations in the enclosed wing environment to better enable operator access and reduce production time.This paper describes a recent study that applied design for assembly and maintainability principles and CATIA v5 computer aided design software to identify small design changes for wing systems installation tasks. Results show positive impacts for ergonomics, production time and cost, and maintainability, whilst accounting for aircraft performance and machining capabilities.

Airborne asbestos exposures associated with gasket and packing replacement: A simulation study and meta-analysis

Exposures to airborne asbestos during the removal and installation of internal gaskets and packing associated with a valve overhaul were characterized and compared to published data according to different variables (e.g., product, equipment, task, tool, setting, duration). Personal breathing zone and area samples were collected during twelve events simulating gasket and packing replacement, clean-up and clothing handling. These samples were analyzed using PCM and TEM methods and PCM-equivalent (PCME) airborne asbestos concentrations were calculated. A meta-analysis was performed to compare these data with airborne asbestos concentrations measured in other studies involving gaskets and packing. Short-term mechanic and assistant airborne asbestos concentrations during valve work averaged 0.013f/cc and 0.008f/cc (PCME), respectively. Area samples averaged 0.008f/cc, 0.005f/cc, and 0.003f/cc (PCME) for center, bystander, and remote background, respectively. Assuming a tradesman conservatively performs 1–3 gasket and/or packing replacements daily, an average 8-h TWA was estimated to be 0.002–0.010f/cc (PCME). Combining these results in a meta-analysis of the published exposure data showed that the majority of airborne asbestos exposures during work with gaskets and packing fall within a consistent and low range. Significant differences in airborne concentrations were observed between power versus manual tools and removal versus installation tasks. Airborne asbestos concentrations resulting from gasket and packing work during a valve overhaul are consistent with historical exposure data on replacement of asbestos-containing gasket and packing materials involving multiple variables and, in nearly all plausible scenarios, result in average airborne asbestos concentrations below contemporaneous occupational exposure limits for asbestos.

El archivo del diario “Pueblo”. Un referente para la historia de la prensa en España durante el franquismo y la transición democrática

This article reviews daily “Pueblo’s” documentation conservated in the General Archive of Administration (Spain), as unknown source for the study of history of the spanish press for the Franco Era and the first time of the Spanish Transition. This lack of knownledge is not accidental, is due to had not worked a large part of the documentation in the record, this fact hampered their access to research. In order to repair this problem in the last years have been carried out the installation tasks and description in order to facilitate the inquiry.