Visualisation Development for The Virtual Construction Site

Transcription

1 UNIVERSITY OF WOLVERHAMPTON SCHOOL OF ENGINEERING AND THE BUILT ENVIRONMENT Visualisation Development for The Virtual Construction Site David Heesom and Lamine Mahdjoubi This research is funded by the Engineering and Physical Sciences Research Council s research programme award no GR/N00876 as part of the Innovative Manufacturing Initiative

2 Visualisation Development for The Virtual Construction Site Visualisation Development David Heesom and Lamine Mahdjoubi

3 Published by School of Engineering and the Built Environment University of Wolverhampton Wulfruna Street Wolverhampton WV1 1SB United Kingdom First Published April 2002 ISBN: All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronically or mechanically, photocopying, recording or otherwise without the written permission of the publisher and the copyright holder. Requests for such permission should be made to the publisher in writing to the above address. All information was correct at time of publication. D. Heesom and L. Mahdjoubi 2002

4 The Virtual Construction Site Visualisation Development Executive Summary This document presents a report on the software developed for the Visualisation Development for the Virtual Construction Site (VIRCON) project. The report reviews the rationale behind software development and clearly identifies how the tools integrate with the other programs of the VIRCON system. The aim of the development was to be able to visualise in 4 dimensions not only the construction process, but also the space used throughout the construction phase. During the development stage, issues were raised that required further exploration. In order to resolve these issues, software tools were developed that allowed the visualisation of these specific spaces and provided this information to other tools in the VIRCON system to assist the spatial analysis. The following presents a brief summary of the motivation for each developed software tool: 1. In order to assign resources with their spatial requirements, a library of resources is required. Resource Manager (ResourceMan) allows the planner to generate a library of resources that can be included as required into the construction schedule. This library is divided into General Resources (human and general resource) and Plant Resources (plant and temporary objects). The principle underlying the tool is the generation of an extensible library of resources that requires space to operate on the construction site. For each of the resources, stored in the generated library, various spatial attributes, (e.g. work area required), are assigned and stored. This information can then be read directly by Microsoft Project and used with standard resource allocation tool. The objects generated and stored as plant and temporary works are also assigned spatial attributes. For each of the objects created in the library the spatial requirements are stored. These can be read by PlantMan to allow the inclusion of plant into the weekly spatial analysis. 2. The development of a full spatial analysis of the construction site during any stage of the process, plant and temporary work objects have to be taken into account. Plant Manager (PlantMan) provides the construction planner with the ability to utilise drag and drop technology to position plant and temporary work objects onto dynamically generated weekly site layouts. PlantMan uses the geometric temporal information stored in the VIRCON database to automatically generate weekly site plans, showing construction products that are both complete and under construction. PlantMan also uses information stored in the resource library generated by ResourceMan software. The library of plant / temporary works objects is loaded into PlantMan and can be assigned to the generated weekly layouts, using the drag and drop principal. In addition to assigning these workspaces, PlantMan also present the user with the ability to assign dynamic objects to the construction site. The Interactive Path Assigner within PlantMan allows the planner to create route paths for specific plant objects for any given week during the construction phase. This information is necessary to facilitate a more realistic dynamic site visualisation. - i -

5 PlantMan produces report and geometric information for use by the planner. A report can be generated to highlight the amount of space used by construction plant during any week of the project. Geometric information is also output from PlantMan for use by the developed AreaMan software. The weekly layout of the construction site, including plant space used, provides a mark up plan for use with AreaMan. 3. Conflicts that exist between temporary works and Plant can have an adverse affect on productivity. In order to detect conflicts in 4 dimensions between constructed entities and temporary works, Clash Manager (ClashMan) was developed. This tool allows the detection of conflicts between the building product and temporary works in 4 dimensions. Detected conflicts between objects are stored and reported to the planner either in a report format or in a graphical format through the 4D visualisation. Collision information is directed to the 4D visualisation software allowing the planner to view potential collisions in 4D, in realtime, allowing a greater awareness of potential problems. 4. Visualising the construction in 4 dimensions provides the planner with a more intuitive view of the construction sequence. Product Space Visualiser (SpaceVis) is an interactive 4D-viewing tool for the VIRCON System. This tool allows the planner to view and interact with the construction site, during any stage of the construction process. SpaceVis is an independent software tool that generates virtual reality objects to represent both the construction product and site space utilisation. This information is read from the VIRCON database, the developed PlantMan tool and the Critical Space Analysis, generated by the SpaceMan software. The construction planner can use this software to view a complete real time visualisation of the construction site, during any stage of the schedule. The 4D visualisation produced is also interactive and as such the planner can interact with the simulation querying intelligent objects in the simulation and obtaining information about their location, the activity they relate to, and any potential time-space conflicts that exist. In summary, the software tools assist the construction planner in developing a complete spatial visualisation of the construction site. Each of the tools has been developed as a standalone software application, requiring no proprietary software and hence reducing the cost to the construction company. The software tools have been developed to fully integrate with the other VIRCON prototypes and require minimal technical input from the planner. Collaboration between all parties in the construction process is key to the successful delivery of a project and so each of the tools has been developed with the capability to become Internet enabled. Each package has the ability to read database information from a remote site and the use of VRML to present an interactive 4D simulation. This enables the viewing of the simulation over the Internet. - ii -

6 The overall rationale for software development was guided by the following criteria: Ease of use: It was decided to select a browser-based system with real-time communication capability. This enables planners to interact with the various programmes through a VRML interface. In addition, this technology allows planners to access and display data in real-time, making software use more interesting and intuitive. Interactivity: It was deemed important to allow a high level of interactivity to allow users to tailor presentations to their own exact personal needs. Collaboration and easy data sharing: Collaboration is considered as key to software development. As all the developed prototypes are web enabled, they allow data sharing and concurrent interaction between various stakeholders. Any data that Internet infrastructure can be used by the developed software and no special applications are needed Adaptability: Adaptability is also central to software development. The flexibility of some tools (such as ResourceMan) enables planners to adapt the programme to suit their own requirements. Extensibility: As the prototypes are web-enabled, they allow easier integration of emerging Internet technologies. In addition, they enable users to develop and extend the programme. Software proprietary independence: It was judged important to deliver tools, which are independent of proprietary developers. As a result, of the adoption of the Web-technology, the support cost for such a platform is reduced. Integration: Integration with other applications and databases was also considered as a key component in software development. Automation: Automation of certain routines and data was deemed necessary to make easier and quicker for planners to explore, analyse and display relevant information. - iii -

7 Table of Contents 1.0 Introduction General Introduction Structure of Report Research Methodology Background Mechanical and Electrical Trades Groundwork Operations Aims and Objectives Previous Research Initiatives D Visualisations Development Approach System Development Introduction VIRCON Resource Manager (ResourceMan) Overview Software Rationale Information Flow User Interface and User Interactions VIRCON Plant and Temporary Resource Manager (PlantMan) Overview Software Rationale Information Flow User Interface and User Interactions VIRCON Temporary Works Clash Identifier (ClashMan) Overview Software Rationale Information Flow User Interface and User Interactions VIRCON 4D Virtual Reality Project and Space Simulator (SpaceVis) Overview Software Rationale Information Flow User Interface and User Interactions Integration with VIRCON Software Overview Software Integration VIRCON System Integration Conclusions Overview Limitations ResrouceMan PlantMan ClashMan SpaceVis Recommendations for future development References iv -

8 Table of Figures Figure 1: Mechanical and Electrical Project Schedule...3 Figure 2: Resource breakdown for the M&E work packages...4 Figure 3: Mechanical and Electrical space usage...4 Figure 4: Additional Equipment required for M & E Tasks...5 Figure 5: Work / Spatial Breakdown Structure for piling activity...6 Figure 6: Project Schedule for Groundwork s Operations...7 Figure 7: Site and Piling layout for UCL Hospital...8 Figure 8: ResourceMan Information Flow...14 Figure 9: ResourceMan start up Interface...14 Figure 10: Resource attributes input dialogue...15 Figure 11: PlantMan Information Flow...17 Figure 12: Level Datum Assignment...18 Figure 13: Product to Level Assigner...19 Figure 14: PlantMan Main User Interface...20 Figure 15: Drag and Drop Plant Objects from the Resource Library...21 Figure 16: Assigning Dynamic Movement Paths for Plant Objects...21 Figure 17: Extract from Plant Space Usage Report...22 Figure 18: DXF Site Layout Generation Routine...22 Figure 19: ClashMan Information Flow...24 Figure 20: ClashMan User Interface...25 Figure 21: Example of collision detection Report...25 Figure 22: SpaceVis Information flow...27 Figure 23: VRML Generation Process...28 Figure 24: Animated path generation...29 Figure 25: Selection of monitoring date for 4D Simulation...30 Figure 26: 4D VRML view of construction products...31 Figure 27: 4D VRML View of Plant Spaces assigned using PlantMan...31 Figure 28: Plant Space attributes shown in 4D information window...32 Figure 29: 4D Simulation Control Panel...32 Figure 30: Microsoft Project viewing Window...33 Figure 31: Software integration...34 Figure 32: VIRCON System information flow...35 Figure 33: VIRCON Analysis configuration v -

9 1.0 INTRODUCTION 1.1 General Introduction Building on the work undertaken in Task 2 of the VIRCON project, Task 7, Visualisation Development, uses the information stored in the VIRCON database to develop a real time simulation of the construction process. Initially the task focused on the development of simulations including the specialist trades of Mechanical and Electrical and Groundwork operations. This was an area identified by Riley (1998) who recommended that the modelling of 4D construction operations be focused on HVAC, Electrical, Plumbing, Fire Protection, Carpentry and Curtain Wall operations as these areas caused many problems during construction. Research into these areas of the construction process was undertaken using information provided by Asea Brown Boveri (ABB) Consultants, who were responsible for the Mechanical and Electrical work package on the Teesside School of Health Project and BCJV, a joint venture between Amec Capital Projects, Balfour Beatty and Haden Young, who are undertaking the groundwork operations for the University College London new Hospital (UCLH) development. To consolidate this research, work was also carried out with Stent foundations to develop work breakdown structures and general overviews of groundwork operations and how these could be best visualised. This task seeks to develop a visualisation tool that allows building products and processes to be viewed in a two and three-dimensional format. In addition to visualising the construction process in 4 dimensions, the suite of tools developed also enables graphical input and output for the VIRCON space analysis programs AreaMan and Spaceman. 1.2 Structure of Report This report presents the development process of software developed for task 7 of the VIRCON project. Section 2 of this report presents the background to development and also presents a brief overview of previous work undertaken in the area of visualisation simulation. From these findings a research approach is presented which forms the basis of the software tools developed during the development process. Section 3 presents the system development of the 4 key tools developed to assist the visualisation development, ResourceMan, PlantMan, ClashMan and SpaceVis. A detailed technical review is presented demonstrating the information flow through each of the systems and the user interactions. Section 4 highlights the integration of the tools developed under this task. In addition to reviewing how each of the tools interacts with each other, this section also illustrates how the tools developed interact with the other software elements of the VIRCON system. Section 6 presents conclusions and highlights any potential limitations of the developed tools. This section also demonstrates areas of future research and - 1 -

10 methods to enhance the software tools developed to provide more robust simulations to be generated

11 2.0 RESEARCH METHODOLOGY 2.1 Background In order to develop a methodology for software development, this task initially focused on groundwork operations and service installations. These are deemed to provide the most challenging area of spatial analysis for the construction planner. Additionally, it identifies and documents the Work Breakdown Structures for various groundwork and M&E operations Mechanical and Electrical Trades In order to develop a greater understanding of the Mechanical and Electrical operations, meetings were held with ABB Consultants. ABB were responsible for the M&E operations on the Teesside School of Health building. Relevant information was obtained on the Work Breakdown Structure and the Equipment used during each stage of the project. The project plan for the M&E aspect of the work can be seen in Figure 1. Figure 1: Mechanical and Electrical Project Schedule Daily labour records were kept by ABB depicting the number of operatives for each of the tasks shown on the project plan and also the additional temporary works objects required. Using this information, a review was compiled to show the number of operatives and equipment used for each task on a daily basis. This resource information was input into the VIRCON database to assist in the visualisation development. An extract from the compiled personnel / task data is shown in Figure

12 Figure 2: Resource breakdown for the M&E work packages Using this information, an initial space usage plan was compiled. This involved drawing workspaces onto the plans, showing the overall site and the mechanical and electrical constructed products. An illustration of these plans can be seen in Figure 3. Figure 3: Mechanical and Electrical space usage These plans took into consideration the labour used for each task within the Mechanical and Electrical work packages. Following consultation with the M&E contractors, their method for undertaking the work was taken into account. Whilst this provided an initial insight into how the work was undertaken in this project, it only took into account the direct labour required for each task. This data did not take into account the numerous supporting objects that require space in order to undertake the task. A list of the equipment used by the contractors to undertake each task can be seen in Figure

13 Figure 4: Additional Equipment required for M & E Tasks The research undertaken with ABB Consultants demonstrated that not only does labour have to be taken into account during space analysis but supporting plant and temporary works play a vital role in analysing space consumption. For many mechanical and electrical tasks supporting plant is required, for example scaffold towers and telescopic trucks. These factors are required to be taken into account for both the generation of a comprehensive space analysis and visualisation Groundwork Operations In order to develop a broad knowledge of groundwork processes, meetings were held with Stent foundations and BCJV personnel in order to develop a work breakdown for various groundwork operations that included the spatial requirements during each stage. From the meetings it is apparent that in addition to labour, plant equipment and safety areas are also of great significance in groundwork operations. Following the meetings a breakdown was developed in conjunction with various groundwork engineers to depict the time requirement and the spatial requirement at each stage. A typical example of a breakdown for the piling process was developed. Approximate layouts were generated for each stage of the of the process and these can also be seen in Figure 5-5 -

14 Task Approx Time Resources Required Clear Site Various Plant / Human Attach boring rig to 15mins Plant / Human C50 crane Approx Spatial Layout Bore to a depth of 3m approx. 25mins Plant Replacing boring rig with vibrating rig Drive pile sleeve into ground to depth of approx. 20m Replace vibrating rig with boring rig Bore out earth from sleeve 15mins 45mins 15mins 30mins Plant / Human Plant Plant / Human Plant Lower in pile skin and prefabricated steel cage Concrete delivered to site Pour concrete into pile skin 10mins Plant / Human - Plant 20mins Plant / Human Remove pile sleeve either by vibrating or screw as above Back fill earth to pile sleeve 20mins 15mins Plant Plant Wait for concrete to Various None cure Construct pile cap Various Plant / Human / Temporary Works Figure 5: Work / Spatial Breakdown Structure for piling activity - 6 -

15 In order to further develop and understanding of the groundwork processes a case study was used. Work was undertaken with BCJV to obtain detailed information relating to the piling and groundwork operations for the UCL Hospital development. The methodology employed for groundwork operations varied in many respects to the one used for the mechanical and electrical trades. The task breakdown for groundwork operations relates to a group of objects (for example a group of piles) rather than the construction of one product. This resulted in larger execution space packages being assigned to tasks. As seen in Figure 5, the extract of the project plan for placing piles is broken down into packages and these packages relate to groups of piles located by the structural grid lines. Figure 6: Project Schedule for Groundwork s Operations For each of the tasks on the construction schedule plant and temporary works objects were required for the successful execution of the task. Additionally safety areas were required around the site of the work package both during the task execution and after execution, for example for concrete curing. In addition to the execution space required by plant objects it also became apparent from the study that during work processes paths were of vital importance. Particularly on the UCLH case study the site was of a constrained nature and so access paths for plant was important. Figure 7 illustrates the layout of the piles for the UCL hospital development

16 Figure 7: Site and Piling layout for UCL Hospital The study of groundwork operations and their spatial requirement reinforced the theory postulated for mechanical and electrical trades. In order for a complete spatial analysis to be undertaken, the space requirements of both plant objects and temporary works are required to be observed. Due to the nature of groundwork operations considerable plant is used and this requires both execution space and hazard areas around the plant. Additionally temporary works are required for example for pile cap construction. 2.2 Aims and Objectives The aim of the task is the production of a prototype system to allow the visualisation of both the constructed product and the space required during the construction phase. This system would build on previous 4D systems as it would enable the reading of geometry from the VIRCON database and would allow the results of critical space analysis calculations to be viewed in both 3 and 4 Dimensions in a realtime interactive environment. Initially the system was envisaged to produce visualisations of specialist trade operations, however these processes could not be realistically visualised without the concurrent visualisation of the whole building. The research into specialist trade operations highlighted that plant and temporary works are required for construction operations. This is true not only for groundwork and service installations but also for general construction tasks. In order to achieve the aim of developing a visualisation system various objectives were defined. These objectives included: The development of a Real Time visualisation system that would provide the user with a 4D simulation of the construction process. The ability of the developed system to operate independently of any proprietary software systems, whilst also providing an intuitive and easy to use system

17 The development of the use of Space-Templates discussed by Heesom and Mahdjoubi (2002b) that would allow a more accurate 4D representation of the construction site. These would allow the planner to input space required by plant and temporary works objects. The ability to incorporate paths into the simulation. Research showed that paths are of vital importance to the construction processes in particular specialist trade operations and are required to be incorporated into the simulation. 2.3 Previous Research Initiatives D Visualisations Producing a 4D simulation involves linking a 3D graphic model to a construction schedule through a third party application (McKinney et al 1996). As documented by Heesom and Mahdjoubi (2002a) various research efforts have been focused on the delivery of the 4D Visualisation of construction projects. The principle concept of 4D Simulations has been documented in the manufacturing industry for some considerable time to present the production process over time and has enabled the reduction of cycle times considerably (Jenkins, 1998). This virtual assembly planning allows the user to check and highlight any potential problems or conflicts in the virtual domain before they actually occur in the real world (Korves et al., 1996). One of the first initial research initiatives in the area of 4D CAD for the Construction industry was reported by Martin Fischer in Since then various projects have been undertake at the Centre for Integrated Facility Engineering (CIFE) at Stanford University, USA. These projects include 4D Annotation (McKinney 1998), evaluating construction schedule logic (Koo et al.,1998), Construction Method Models (Aalami, 1998) and Time Space conflict Analysis (Akinci et al., 1998). Another early prototype to explore the area of 4D CAD for construction was the Virtual Reality Planner (VR Planner), a 4D simulation tool developed at the University of Strathclyde. The system aims to provide a virtual reality interface to allow the user to visualise the various stages of the construction project utilising the Superscape Virtual Reality Toolkit software package (Retik, 1995). Normally 4D simulations are considered once the design has been substantially completed and emphasis turns to the sequencing of the product assembly (Tommelein, 2000). 4D CAD at the present time has been described as techno-construction-centric (Barrett, 2000) whereby the thrust of work is based on the technological issues with emphasis on the construction phase. It is also being suggested that project managers and planners that use 4D simulations are more likely to allocate resources more effectively than those who do not (Fischer, 2000). The use of 4D Planning also assists the planner in avoiding scheduling conflicts, analyse constraints and evaluate alternative construction methods (Vaugn, 1996) Research undertaken by Akinci (2000) demonstrated that 4D simulations could be used to highlight potential time-space conflicts on the construction site. This work aimed to detect conflicts in four dimensions, categorise the conflict according to - 9 -

18 taxonomy of time-space conflicts developed and prioritise the multiple types of conflicts between the same pair of conflicting activities. Work undertaken by Fischer (2001) demonstrated that 4D visualisations could provide a substantial cost benefit to the construction planning process. Presently various 4D visualisation software is commercially available. Packages such as Schedule Simulator (Bentley Systems Inc 2001), SmartPlant Review (Intergaraph, 2001), Project Navigator (VirtualStep Inc 2001) and FourDviz (Balfour Technologies, 2001) are available with costing varying according to the technology. In each of the cases either a CAD based system is used or alternatively Virtual Reality Modelling Language is used to present a real time model. Each of these systems provides the user to link the 3D product model to the schedule of construction tasks. However the linking of the product to process is manual and additionally plant and temporary works space objects could not be directly applied to the schedule and hence the 4D simulation (Heesom and Mahdjoubi, 2002b). Commercial software has been used to explore the application of 4D concepts carried out as a collaborative effort between CIFE and Walt Disney Imagineering (WDI) (Goldstein, 2001b). 4D simulations have also been used on large complex projects such as airport construction where they can provide crucial information to airport planning bodies, enabling the state of the airport to be visualised at a discrete point in a way that a 3D model of the final project could not (Edwards and Zeng, 1997). 2.4 Development Approach The research undertaken into the areas of Specialist trade visualisation demonstrated that no visualisation of specialist trade operations would be complete without the concurrent visualisation of the rest of the building product. Therefore a methodology was developed that allowed both the visualisation of Specialist trades in conjunction with the development of visualisation techniques for the whole building. Additionally it was also demonstrated that the undertaking of specialist trade operations required considerable plant and peripheral equipment in addition to the general labour resource i.e. manpower. For this reason an approach was developed to allow the inclusion of plant and other temporary works objects into the space analysis of the construction sequence. Geometry for the construction product is stored in the VIRCON database developed during Task 2 of the VIRCON Project The set up of the VIRCON database is assumed to be complete and the process of database set up is documented in Dawood et al. (2001). The key deliverables of the system would be: A tool to allow the planner to generate a plant library that could be used as a drag and drop tool to add plant and temporary works objects to the weekly construction layout

19 The development of a tool to allow the planner to add plant and temporary works objects to weekly plans. This would read information directly from the library and the VIRCON Database. The development of a tool to allow the planner to input paths required during the construction process. A tool to provide the ability to detect clashes and collisions between the building product and temporary works objects / plant objects during all stages of the construction process. A 3D / 4D visualisation tool to allow the planner to view the spatial layout of the site during any stage of the construction process. This tool will extend 4D visualisations by allowing the viewing of critical space analysis and space usage in addition to building product

20 3.0 SYSTEM DEVELOPMENT 3.1 Introduction In order to view the activities and the space usage in 4D, work was carried out to develop a simulator that has the capability to read the geometric information stored in the VIRCON database. This information is then used to generate 2D and 3D visualisations using the Virtual Reality Modelling Language (VRML). The simulation module is part of a suite of prototype products developed to enable visualisation and simulations of both product and spatial requirements. Each software prototype is developed as a stand-alone package and database information is accessed and written using Database Access Objects (DAO) 3.6. The input to each of the software tools emerges from the VIRCON database, and the Uniclass information associated with each task is then used to obtain geometric information relating to the building products. This information is then taken as input for the generation of the 4D VRML geometry. The basis of the simulations is looking on a work period of 1 week. Work undertaken by Kelsey et al. (2001) demonstrated that a 1 week planning period is a substantial level of detail and also that the micro planning of construction tasks within this period can be undertaken by the works supervisor. 4D VRML simulator produces weekly schedule information on the project plan. Structured Query Language (SQL) is used to query the VIRCON database to determine which tasks are being undertaken during each week of the project. Development of the software tools was undertaken using information from the Teesside University School of Health (SoH) Project. This information was used to populate the VIRCON database developed in Task 2 of the VIRCON Project and this formed the basis of software development as well as the beta testing of the software during the development stages

21 3.2 VIRCON Resource Manager (ResourceMan) Overview This software prototype was developed to enable the planner to develop a reusable library of construction resources. This resource library would include both general resources and plant / temporary works resources. For each of the types stored in the library the corresponding space requirements are stored Software Rationale This software was developed to assist the planner in developing a library of resources that can be read into the construction scheduling process. It has been suggested that work area required can vary (Kelsey et al., 2001) however this figure could vary according to the operator type. This tool allows the planner to input the spatial requirements of operatives within their organisation who undertake a specific trade. Once generated, this library can be read into Microsoft Project and these general resources can be read into the resources section of the project and hence allocated to a specific task. In addition to the general resources ResourceMan also allows the planner to generate a library of supporting objects such as Plant and Temporary Works. These objects are required for many construction operations and can vary between both companies and projects. The extensible library allows the planner to create new objects, for example if a new type of plant is to be used. For each of the objects created in the library the spatial requirements are stored and these can be read by PlantMan to allow the inclusion of plant into the weekly spatial analysis Information Flow Figure 8 highlights the information flow through the ResourceMan tool. A library of both general and Plant / Temporary Works resources are stored along with their spatial attributes. Each library is extensible and stores unique names for all resources. The technology used allows the planner to generate more than one library and these can be stored in separate files allowing specific libraries to be generated for various project types. The output of the ResourceMan tool is a Microsoft Access 2000 database file that can be read as input by both Microsoft Project and PlantMan (discussed in Section 3.3)

22 Create /Open Resource Database Assign attributes for General Assign attributes for Plant / Temporary Works ResourceStandards.mdb Microsoft Project PlantMan Figure 8: ResourceMan Information Flow User Interface and User Interactions On Program start up the user is presented with the main interface as shown in Figure 9. This allows the planner to generate a new resource library or to open an existing library to amend resource objects. Figure 9: ResourceMan start up Interface Once a new library has been generated the user can select to either amend the general resource library or the plant resource library. Selecting to edit the library will provide the planner with the library interface. The Graphical User Interface (GUI) for the Plant library can be seen in Figure

23 Figure 10: Resource attributes input dialogue This allows the planner to update existing resources or add and delete resource objects currently stored in the library. Uniclass is also used to identify the resources used. The planner can select the generic description of the resource from the drop down list and from this description the associated Uniclass code is stored in the library and passed to the output documents. All of the descriptions in the Uniclass list are taken from Table M of the Uniclass Standards relating to Construction Aids. A built in function of the libraries ensures that no resource names can be duplicated thus ensuring that no confusion occurs when resources are being assigned to tasks or to the weekly spatial layout

24 3.3 VIRCON Plant and Temporary Resource Manager (PlantMan) Overview The PlantMan prototype was developed to assist the planner in generating weekly spatial layouts of the construction site that include Plant and Temporary Works objects. The tool allows the interactive inclusion of plant and temporary works objects and route paths used by plant to be included in the space analysis and the 4D visual simulation Software Rationale The aim of PlantMan is the provision of the ability of the planner to include plant and temporary works objects into both the Critical Space Analysis process (North, 2001) and the visualisation process. Additionally the visualisation of route paths for plant objects is of vital importance and so this functionality is also included. Previous work in the area of site layout planning (Tommelein, 1994) has demonstrated that using drag and drop templates of objects representing material objects is beneficial in developing a site layout plan. This theory is used and extended further to provide drag and drop plant space objects. Temporary works and plant object require considerable space to operate on the construction site, and the space utilised during their operation is unable to be utilised by other activities. Currently planners mark up plans to show areas that are unable to be used by activities manually however this tool aims to provide a semi automated approach to this mark up whilst extending this process into the digital genre therefore allowing more accurate and robust layouts. Once these weekly digital plans are generated, other tools within the VIRCON system can use them. The available space on the site in any given week can be viewed and this can be used to highlight areas that are available for various work packages. The information generated by PlantMan will also provide the basis for the 4D visualisation system discussed in Section Information Flow Figure 11 highlights the information flow through the PlantMan system. Input information is taken from both the VIRCON database and the resource library generated by ResourceMan. Using the task and geometric product information stored in the VIRCON database, weekly plans are generated of the constructed facility. These 2D plans show both the work that has been completed to date and the work that is currently being undertaken in the week. This selection of process product is undertaken by using the Uniclass information stored in the database. Information pertaining to plant objects and their spatial requirements are in put from the ResourceMan library. This loads the entire plant library from the selected file and stores these for use by the planner. The information flow layout through the PlantMan system can be seen in Figure

25 Weekly DXF VIRCON Database Assign number of Building Floors Plant Space Usage Reports Assign datum levels to Building Floors Query VIRCON Database for geometry of products being undertaken per week Query VIRCON Database for geometry of products completed in each week Select date to assign Plant / Temp Works objects Draw weekly layout plan using PlantMan interactive whiteboard Select resource to add to site plan from resource library Drag and Drop Plant template onto weekly layout Assign path / routes for plant for the week and assign plant templates from resource library to paths Plant Resources sent to VIRCON DB Resource Library User relates product tables to building levels Plant-Space Loaded Weekly Product Geometry Output Plant Man Process Input Figure 11: PlantMan Information Flow

26 Once the 2D mark up plans have been generated and marked up by the planner to include all the plant objects and the paths required by various plant resources for a week this information is output for various uses. Four streams of output exist from PlantMan: Weekly DXF plans of the spatial layout of the construction site. The DXF files are stored in AutoCAD 2000 DXF format and show the information for each level of the constructed facility during each week of the project. These DXF files form the input for the developed AreaMan tool, a mark up tool to allow the creation of available workspaces for each week of the project. A Weekly space report of the construction site. This is a text file describing the amount of space used by plant and temporary works objects in a single week on each level of the constructed facility. Exporting of the plant / Resource information used to the VIRCON database. Resource information is stored in the Resources Table of the VIRCON database. All plant and temporary work information is extracted from PlantMan and included in the resource Table. This ensures that other developed simulators can use the plant resource information in visualisations Complete weekly geometric information. Entire geometry of the construction site for each week is extracted for use by the 4D simulator SpaceVis discussed in Section 3.5 This information includes building product, Plant Space and path geometric data User Interface and User Interactions On initialising the program the user selects the VIRCON database and the resource library that is to be used for the mark up operations. Once the VIRCON database is selected the number of levels (or floors) that exist with the building is taken from the Building table in the database. The user is then prompted to provide datum levels for each of the floors (this could be finished floor level). If this process has been done previously, the user is given the option to use the values previously entered or to enter new values for the level datum s. Figure 12: Level Datum Assignment Once this has been completed, the product tables in the VIRCON database need to be associated with the relevant levels or floors in the simulation. This can be done either automatically or manually. If the manual method is chosen, the user selects a building level from the drop down list and a list of products that exist on that level is presented. The user selects the products required and uses the

27 Assign Tables button. If the Automatic approach is selected the user presses the Continue button and all of the products associated with a particular level are associated. This process is undertaken by looking at the product table name and associating to a building. The product table names follow the convention: PR_01_00_Foundation = Product table for foundation in building ID 01 PR = Prefix for product table 01 = Building ID (i.e. 01, 02,..., 99) 00 = Building Level (i.e. 00 = Groundwork, 0G = Ground Floor, 1F = First Floor, 2F = Second Floor, 0R = Roof, 0A = Atrium) Foundation = Generic Product Description Figure 13: Product to Level Assigner Once assigned the 2D geometry is generated for each week and each level of the construction project. The planner can then select a date to view the status of the project as shown in Figure

28 Figure 14: PlantMan Main User Interface Once the weekly layout has been selected the planner can add plant and temporary works objects as required. The library is loaded into the drop down list and the dimensional attributes of the object are displayed. If required the user can update the geometry of the plant object individually. For example if a specific safety zone is required for the object, for example a hazard area around scaffold tower this can be added to the dimensions prior to the object being added to the layout. An example of adding plant objects to the layout can be seen in Figure

29 Figure 15: Drag and Drop Plant Objects from the Resource Library Other attributes that can be amended during the positioning of plant objects include the rotation of the object. This can be set to 0 or 90 degrees as all objects are deemed to be rectangular. A further option allows the planner to add the object for more than the week selected during the mark up process. It is often the case that plant or temporary works will exist for more than one week in a particular place and so the ability is present to assign the object for numerous weeks. Once added the object will appear in the same position for the weeks stipulated. Figure 16: Assigning Dynamic Movement Paths for Plant Objects

30 Once all plant objects have been added for a particular week dynamic route paths can be assigned. Using the Interactive Path Assigner the planner can drag a route path onto the weekly layout and can attach a plant object stored in the library to the path. An example of assigning a path to the weekly layout can be seen in Figure 16. Following all of the assigning of Plant Objects and route paths a space report can be generated. Spatial information is stored in a text file presenting information on the total space occupied by the building product and space occupied by the plant objects for each week of the project. Figure 17: Extract from Plant Space Usage Report Finally once all plant objects have been added to the weekly plans a set of plans are exported in DXF format for use with the AreaMan mark up tool. An example of an exported DXF file is shown in Figure18. Figure 18: DXF Site Layout Generation Routine

31 3.4 VIRCON Temporary Works Clash Identifier (ClashMan) Overview The Temporary Works Clash Identifier (ClashMan) was developed to assist the planner in detecting collisions that exist on a weekly basis between plant and temporary works objects positioned using the PlantMan tool and completed products in the building. ClashMan allows the planner to test for collisions between these 2 sets of objects in 3 dimensions using a developed collision detection algorithm. The collisions can be detected for a particular week of the project or once all plant objects have been assigned collision detection can be undertaken for the entire project on all levels of the constructed facility Software Rationale The aim of ClashMan is the ability to detect collisions and conflicts in both 3 and 4 dimensions. Once detected these collisions can be viewed in the 4D visualisation tool discussed in Section 3.5 During the positioning of objects and paths in PlantMan, there exists the opportunity for collisions to occur between the constructed product and the object placed. ClashMan makes use of a derived algorithm based on the raw collision detection theory (Sinjur, 2001). This algorithm checks each vertex of the plant space objects to identify if any collisions are taking place with construction products. Some previous work has used algorithms to identify collisions that exist between static workspaces (Akinci, 2000) however this prototype extends this theory to include the detection of collisions between product and dynamic plant workspaces Information Flow Figure 19 demonstrates the information flow through the ClashMan system. Input is taken from the VIRCON database and from the weekly geometry output of the PlantMan system. This includes the geometry of both completed building products and the plant / temporary works objects placed. The user selects the VIRCON database from its stored location. Once the input information is selected the user can select to perform collision detection on a selected week and a selected level or perform collision detection for all weeks on all levels of the building being constructed. If a collision is detected the geometric information is written to a database file and stored in readiness for use by the 4D simulation software

32 VIRCON Database Select Level and Date for collision detection Geometric Properties of colliding objects for use with ProSpaceVis Check Vertex collisions between Plant Space Objects and Building Products Write geometric data of any colliding objects found to DB PlantMan Geometry Information Automated detection of collisions for all weeks and all building levels Text report of the number of collisions detected per week per building level Output ClashMan Process Input Figure 19: ClashMan Information Flow The detected information, once stored, can be used to output the collision information using two methods. A text-based report can be generated that provides a list of the collisions that occur with each week of the project The geometry stored can be used to generate Virtual Reality objects allowing the planner to visualise the location of each of the collisions that exist in the site layout

33 3.4.4 User Interface and User Interactions On initialising ClashMan the user is presented with the main ClashMan interface shown in Figure 20. The Planner can then open the VIRCON database from its origin and this will provide the project Start and End dates in the information panels shown at the bottom of the interface. The level (or floor) information for the building is derived from the Building table of the VIRCON database. Once loaded the planner can select to perform collision detection for specific dates or for the entire project using the radio buttons. If a specific week is to be tested the planner can choose a date from the calendar and select a level of the building to check by selecting from the drop down menu. Figure 20: ClashMan User Interface Once detected the collision information can be written to a collision report file which lists all collisions occurring within the project on a weekly and level basis. An example of a collision report output file can be seen in Figure 21 Figure 21: Example of collision detection Report

34 3.5 VIRCON 4D Virtual Reality Project and Space Simulator (SpaceVis) Overview SpaceVis is a prototype 4D visualisation software system, developed to allow the user to visualise the status of the project at any stage of the construction process. Additionally, the tool allows an intelligent and interactive 3D and 4D visualisation of space usage throughout the duration of the construction period Software Rationale The aim of SpaceVis is to provide a visual output to the information generated by the VIRCON database, PlantMan, AreaMan and SpaceMan. The tool will allow the visualisation over time of the constructed product and the spatial loading of the construction site. Additionally the tool allows the visualisation of dynamic route paths followed by plant objects as created by the PlantMan tool. Many previous 4D prototype systems have utilised the Virtual Reality Modelling Language (VRML) to generate the 3D objects. It is also the case that some commercially available software with the ability to present 4D simulations is using VRML. SpaceVis makes use of VRML to generate both building product objects and also space objects (both plant objects and static work areas). Due to the nature of VRML objects can also be made intelligent. This use of intelligent objects is exploited in SpaceVis to enable the planner to interact with the visualisation. The user is able to request information from objects in the visualisation. Dynamic objects can also be used and visualised in VRML. This enables the viewing of objects following paths as generated using the PlantMan Interactive Path Assigner. The ultimate purpose of the software is to provide a Real Time interactive simulation of the construction process whereby the planner can move to any location and view the progress and space usage from any viewpoint Information Flow Figure 22 highlights the information flow through the SpaceVis system. Input information into the simulator is derived from geometric and temporal information stored in the VIRCON database and from the geometry created from PlantMan. All of the geometry generated in VRML is based on a weekly take off of activities and space. The 4D VRML simulator is platform and software independent however in order to view the 3D VRML objects a VRML plug in is required. These plug-ins such as Cortona VRML Client and Cosmo Player are free to download from the World Wide Web. The SpaceVis tool has been developed using Visual Basic Programming Language and utilises class tools developed by EM7 to allow the dynamic generation of VRML code from user input. Once the geometric information is read into the SpaceVis tool, VRML objects are generated to depict the status of the project in each week. The process required in order to generate the VRML components can be seen in detail in Figure