Modelling and
simulation of construction processes using VR technology -
4D
Simulations
and models of the construction process
Still at present construction process
planning typically means scheduling and schedules in Gantt
Chart format. This kind of a schedule is not a particularly good
commucation means for individuals having different background and being not
necessarily familiar with formal scheduling outputs. Nowadays it is essential
to build trust between project parties and give the owners and users
possibility to analyse and give feedback of the construction process plans.
The main reason for problems
originating from project planning is due to the individual's misconception of
reality. Still nowadays a typical situation is to have only two dimensional
drawings as a main background material for planning purpose. Thus,
particularly in the case of multi-storey buildings one needs to have a good
sense of 3D thinking in order to prepare successfully necessary plans. To
increase the quality of the process plans better models and simulations of the
construction process are needed. This is a one way to decrease the duration of
the projects and same time keeping up the certainty that the schedule is
realistic.
4D Approaches
A 4D model combines 3D model with the
appropriate scheduling data. Integration
of the geometrical representation of the building together with scheduling data
has been a topic for many research and development efforts. Different approaches
for this integration are the following (contains links to the
corresponding approaches):
Automation
approach
Automated
generation of 4D models refers to computer applications where a reasoning
engine or engines together with construction operations knowledge are able to
interpret 3D geometric data and produce process plan showing how the building
can be constructed. Examples of the results from this type of research and
development efforts can be found from (Aalami and Fischer, 1998; Froese et
al., 1997; Levitt et al., 1988; Zozaya-Gorostiza et al., 1989).
Linking
approach
(4D Tool - How to create dynamically linked 4D
model?)
'Linking approach' is the area where
the focus of industrial apoplications probably will be. It is reality in the
industry that the schedules and designs will change -> it is vital that we do
not need to create the 4D model all over again. Other point supporting
applications representing Linking approach is that in all projects designs and
schedules have to be done. So, basically the 4D model do not cause much
additional expenses.
Recently VTT
and Eurostep have developed a tool that can create a dynamic and real-time
link between 3D IFC model
and a schedule. 4D Tool
development was partially funded by DIVERCITY - Distributed
Virtual Workspace for Enhancing Communication within the Construction Industry,
IST-1999-13365.
Lego
approach
The 'Lego approach' was tested in a pilot project in
Helsinki. The THK project was an eight floor office building by a Finnish
construction company YIT Corporation.
The 4D model was implemented in the
University of Strathclyde by Andrew Layden and Stuart Buchanan. Their work was
based on 2D drawings, some photographs of the building, master schedule and detailed
production plans.
|
The
THK Project can be run using
Viscape. You can get it from here
|
Augmented Reality
Augmented
reality is a combination of a VR model and Telepresence
technology. For example if a vr-model and telepresence image can be viewed together and
synchronized in a way that the user can easily compare the planned schedule and actual
performance [Retik et al, 1997] . In addition the vr model could be used as a pointing
device for telepresence equipment. To receive additional information on some detail on
site the user only needs to point the place in vr-model. Just to give an expression of
augmented reality here is a demonstration of what it could look like.
|
