Ubiquitous location tracking for context-specific information delivery on construction sites

Construction projects are information-intensive in nature and require site personnel to have continuous on-demand access to information such as project plans, drawings, schedules, and budgets. Awareness of a user's context (such as user profile, role, preferences, task, and existing project conditions) can enhance the construction project delivery process by providing a mechanism to determine information relevant to a particular context. Context awareness can also be used to improve security, logistics and health and safety practices on construction sites. Location is an important aspect of context awareness. A location aware application can utilize the knowledge of the user/object location to provide relevant information and services. This paper argues that a successful and reliable location tracking system must be able to track a user's spatial context and deliver contextual data continuously in both outdoor and indoor environments to effectively support construction projects. Research describing the use of Wireless Local Area Network (WLAN) for indoor tracking and Global Positioning System (GPS) for outdoor spatial context tracking is presented, and an integrated tracking technique using WLAN and GPS for ubiquitous location sensing is introduced. The key benefits and technical challenges of such an integrated approach are also highlighted. The presented tracking techniques have been validated in both indoor and outdoor environments to ensure their practical implementation on real construction jobsites

Mixed reality tools as an enabler for improving operation and maintenance in small and medium enterprises

The use of Mixed Reality (MR) tools can improve information retrieval, collaboration and decision making, thus aiding the management of buildings within the operation and maintenance (O&amp;M) lifecycle stages. In this paper, we focus on the use of MR in visualising BIM data to aid building lifecycle management. This paper compares current and emerging MR tools and explores their potential in being applied to O&amp;M of Small and Medium Enterprises (SMEs). MR refers to technology that enhances reality by integrating it with the digital world, such as Augmented Reality (AR), Virtual Reality (VR) and spherical panoramas, known as Photospheres. Current literature on applications and limitations of MR in the O&amp;M cycle for small businesses is explored and the user requirements for implementation and use are elicited. Key requirements are found to be cost, skill level, interoperability, pre-requisite data, interactivity and time. Using these requirements, the state-of-the-art in VR, AR and Photosphere environments is assessed and the contexts in which they are most appropriate are developed. The paper concludes with a number of recommendations for the selection of an appropriate strategy dependent on the maturity of BIM adoption within an enterprise. A number of theoretical and conceptual implications are also developed.</p

On the precision of third person perspective augmented reality for target designation tasks

The availability of powerful consumer-level smart devices and off-the-shelf software frameworks has tremendously popularized augmented reality (AR) applications. However, since the built-in cameras typically have rather limited field of view, it is usually preferable to position AR tools built upon these devices at a distance when large objects need to be tracked for augmentation. This arrangement makes it difficult or even impossible to physically interact with the augmented object. One solution is to adopt third person perspective (TPP) with which the smart device shows in real time the object to be interacted with, the AR information and the user herself, all captured by a remote camera. Through mental transformation between the user-centric coordinate space and the coordinate system of the remote camera, the user can directly interact with objects in the real world. To evaluate user performance under this cognitively demanding situation, we developed such an experimental TPP AR system and conducted experiments which required subjects to make markings on a whiteboard according to virtual marks displayed by the AR system. The same markings were also made manually with a ruler. We measured the precision of the markings as well as the time to accomplish the task. Our results show that although the AR approach was on average around half a centimeter less precise than the manual measurement, it was approximately three times as fast as the manual counterpart. Additionally, we also found that subjects could quickly adapt to the mental transformation between the two coordinate systems

A Conceptual Framework of Quality-Assured Fabrication, Delivery and Installation Processes for Liquefied Natural Gas (LNG) Plant Construction

© 2014, Springer Science+Business Media Dordrecht. Construction productivity issues in the Liquefied Natural Gas (LNG) construction industry can lead to project cost blowouts. Time wasted by construction personnel getting the right information on megaprojects can be a substantial contributing factor. It appears that the communication on site is not cost effective, judging by the number of large project that have experienced budget overruns in the past. More importantly, as-built design documentation often fails the quality test, resulting in operational inefficiencies once the plant has been handed over from Construction to Operation Phase. Common errors during the static prefabrication, dispatch and installation processes can result in serious rework as a significant amount of construction time and budget is wasted. To minimise these problems, this paper recommends to better control the dynamic natures of construction. This study propagates a conceptual framework for assuring quality of modular construction in LNG plants by introducing a Situation Awareness construction environment with well-defined sensing and tracking technologies. While encountering situations inconsistent with plans during construction, such as time delay, fabrication errors, conflicts in terms of accessibility and constructability issues and so forth, sensors mounted in situ can discover such situations and recursively fed back to field personnel. Automation and robotics technologies, such as real-time path planning, collision detection and deviation examination utilizing as-planned building information model, can assist engineers to rapidly react with inconsistent situations and make acceptable decisions instead of partially or entirely suspending the workforce through massive reworks. In this study, we conduct a preliminary study in demonstrating the feasibility of utilizing sensory devices and automatic planning technologies. The expected results of adopting the framework are the quality-assured modular construction and execution plans during construction stages to save rework construction time and budget