Intelligent BIM-Based Drafting & Design For Manufacturing
Modular Construction Research Group
University of Alberta, Department of Civil & Environmental Engineering
Architecturally complex projects require advanced tools. Due to the inherent complexities of innovative structures, 3D modelling and animation can be used to experiment with the construction process on a computer screen in order to prevent potentially costly on-site errors. In this regard, the IRC serves as a hub for research and education on building information modelling (BIM), uniting industry and academia to overcome obstacles that hinder innovation in construction processes. Applications include automated design and drafting, as well as material waste minimization.
FrameX design and drafting software for wood and light-gauge steel frame buildings
Building information modelling (BIM) is an emerging technology in the AEC industry that has seen increased adoption in recent years. Although it is intended to address a wide range of challenges encountered in the AEC industry, BIM can be expanded to fulfil the needs of construction practitioners in terms of designing and drafting, especially for framing and boarding of light-frame residential buildings. Traditionally, framing and boarding activities on site require construction framers to use their practical knowledge and understanding of the overall manufacturing process. Moreover, the design and drafting requirements associated with modular construction exceed those of the traditional stick-built method.
This research focuses on the development of a framing add-on (called “FrameX” ) to Autodesk Revit, which is a popular CAD software in the North American construction industry. The developed add-on can automate the design and drafting of framing and boarding elements, including generation of detailed shop drawings, bills of materials, and cutting layouts for light-frame buildings. The use of this add-on saves a significant amount of drafting time and reduces human error, resulting in an increase in overall accuracy and efficiency of the design and drafting process.
Autodesk application programming interfaces (APIs) and software development kits (SDKs) are used to extend the capabilities of Revit using programming languages such as C#. The research team automated existing features with Autodesk Revit and also added entirely new ones such as this framing add-on.
Framework for automated manufacturing-centric BIM for light wood-framed buildings
BIM technology has the potential to improve the collaboration among multiple stakeholders and to streamline construction projects. In order to increase the adoption of BIM within the Canadian building industry and, in particular, the modular or prefabricated construction industry, the BIM models must be designed with sufficient fabrication details to facilitate the production phase. However, in current practice, fabrication details require substantial manual modelling efforts, thus limiting the utilization of BIM models in the industry. In this context, the aim of this research is to create a framework that can be implemented in drafting software to automate construction details for modular construction. To validate and demonstrate the effectiveness of the proposed framework, various case studies are investigated which put to use the developed tool. The results demonstrate the applicability of the proposed framework to optimize the manufacturing of prefabricated buildings and minimize drafting time and material use.
BIM-based automated design and planning for boarding of light-frame residential buildings
The degree of effectiveness of BIM models in communicating information among project stakeholders plays an important role in determining the construction efficiency. To make a BIM model fit for use by contractors and sub-contractors, it needs to be furnished with sufficient construction detail (i.e., construction-specific information) for specific application needs. Such detailed BIM models are of vital importance in project coordination and decision making in relation to construction material take-off and usage at the construction stage. Nevertheless, developing a construction-centric BIM model through manual modelling is time-consuming and error-prone. Furthermore, trades know-how in the construction industry remains mainly in the minds of experienced trades people and is generally missing from existing design software or is otherwise inaccessible to building designers. As such, construction-centric designs generated by building designers using existing BIM design software usually fall short of practical constructability analysis, resulting in considerable material waste and re-work in the field. This study thus explores a BIM-based automated approach to boarding design (i.e., optimizing and modelling sheathing and drywall layout design) in the light-frame building industry. This approach advances the current practice in the field by adapting BIM design models for construction practitioners in an automated fashion.
BIM-based intelligent design and drafting system for precast concrete building panels
Automating the design and drafting process is the first pillar of construction industrialization. However, the existing manual drafting process is labourious and the results are prone to error and difficult to update. Therefore, this research aims to investigate a new methodology that can automate and optimize the design and drafting process, focusing on precast concrete panel production. This intelligent system is developed for the purpose of achieving automation generation of the detailed shop drawings needed for the manufacturing process, and to reduce the human component involved in the drafting process. An intelligent computer program (parametric modelling program) is developed as an add-on to Autodesk Revit in order to automatically generate the shop drawings for precast concrete panels using Revit API. (Screenshots of the developed add-on for automated design and drafting system are shown below.) The routines and algorithms for designing and drafting precast wall panels are programmed and embedded into the system. The developed Revit add-on, taking an existing architectural model as the input, can produce a set of detailed shop drawings for manufacturing purposes, subject to the relevant criteria and standards (e.g., national building code). Moreover, a detailed manufacturing-oriented BIM model is automatically generated that can be used to obtain a thorough material take-off, thereby laying a foundation for downstream analyses such as automated target costing and schedule analysis.
A framework of BIM-based automated drafting and planning for window manufacturing
This research develops an automated drafting and planning system for window manufacturing. As an engineering-to-order component, a window requires customized design. In current practice, window manufacturers usually obtain the building information based on 2D drawings from the customer. Then, sales personnel will input the specifications to generate a quote and 2D drawings for windows. The information then flows to the Enterprise Resource Planning (ERP) system to generate customer orders for the scheduling and manufacturing department. Several issues with the existing practice are identified: (1) lack of details for 2D drawings of windows; (2) time-consuming manual process for scheduling customer orders; (3) information often missing from the “work traveller” (a sticker that specifies all the window components and hardware information); (4) work traveller lacks detailed data for specific workstations; and (5) the process is highly reliant upon the worker’s experience. The proposed method can address the above issues by implementing manufacturing-centric BIM. A higher-level-detailed design can be developed to improve the design efficiency and accuracy, and specific information for each station can be generated to achieve workstation-based information delivery through the computer, reduce process waste, and reduce human error. In this manner, automation in drafting and planning for window manufacturing under BIM environment can be achieved in order to provide a design and assembly plan complete with a BOM for the window structure as well as manufacturing information for each workstation.
Automated electrical cable routing in residential buildings
The electrical routing process in a residential construction project can be tedious and complex, as it involves tracing and pulling the electrical wires through framing studs and other framing members while connecting the electrical outlets and fixtures along the way. The electrician also needs to be aware of the circuit to which each of these devices belongs.
In current practice, the electrician uses their own judgement and experience to decide the proper route for each electrical cable. Since the electrician has no means to determine the exact length of cable required for a particular electrical circuit, there is a considerable amount of waste along the way, as the wire is routed through sub-optimal paths on many occasions. In many cases the electrician is unable to foresee obstacles when determining the routing path, resulting in material waste and rework.
To solve this issue, we develop an automated add-on within the Autodesk Revit for electrical cable routing. The developed add-on automates the routing of electrical cables to the selected outlets and fixtures and specifies the exact length of electrical cable needed for each circuit. The electrician is also able to visualize the exact routing path for each cable, as the developed add-on is also capable of representing each cable in three-dimensional space. The use of this add-on saves a significant amount of time for electricians and reduces human error, resulting in an increase in overall efficiency.
Automated manufacturing-centric BIM to facilitate building panel prefabrication
With the emergence of BIM, off-site construction is gaining momentum in the construction industry. This construction method can benefit the industry through improved productivity and reduced waste. However, it also poses new challenges to building designers and construction practitioners with respect to building design and construction planning. For example, when designing building products and BIM models, designers needs to consider manufacturing process constraints in order to harness the benefits of manufacturing technology. This is in part due to the fact that, in the off-site construction paradigm, building design must be transformed from product-focused to manufacturing process-driven. In current practice, considerable human involvement and off-site construction knowledge are required in order to adapt the building design (e.g., panelized building objects) to the manufacturing context within the BIM environment. In this regard, this key contribution of this research is the development of a BIM-based algorithm for panelizing building components. For example, the proposed algorithm is capable of determining the granularity of wall panels and optimizing the configuration of multi-wall panels under engineering constraints, thereby improving productivity. The proposed approach is implemented within an Autodesk Revit environment using API. A case study of a residential building is used to demonstrate the proposed approach.
Structural analysis and design software for light frame buildings
In this research we develop a structural analysis and design software solution for light frame wood buildings, called “moc-BIM”, which functions as a software add-on to the popular BIM software, Autodesk Revit. moc-BIM can be used for analysis of floor members, capacity calculation design-checking, and to provide the final sizes of members for shop drawings. All loads and load combinations generated by this tool are compliant with the Alberta Building Code and the National Building Code of Canada. In this add-on, the design capacities of lumber joists are determined according to the Engineering Design of wood 086-14 and the Alberta Building Code, while the design capacities of I-joists and open-web joists are determined according to the Specifier’s Guide.
BIM-enabled design and planning of roof sheathing installation for modular buildings
Off-site construction and building information modelling technology bring benefits to the construction industry in many respects, such as reduced material waste, and lead to solutions that are moving the construction industry toward a more sustainable approach. Nevertheless, despite the uptake of off-site construction methods and BIM, a considerable amount of construction waste in the form of sheathing material (e.g., oriented strand board) is still generated in the light-frame building industry. This research thus presents an automated BIM approach to reducing sheathing material waste by enabling proactive design and planning of roof sheathing installation for modular buildings. Specifically, a BIM-based sheathing layout design algorithm, which incorporates trades know-how, is developed in order to achieve construction design automation. A hybrid algorithm integrating greedy algorithm and particle swarm algorithm is applied in connection with the design algorithm to optimize material cutting plans for the generated layout with the objective of minimizing sheathing material waste. Two case studies are presented to demonstrate the feasibility and effectiveness of the proposed approach in terms of roof sheathing material waste reduction. The results are summarized to provide deeper insights into sheathing waste reduction for more sustainable construction practice.
BIM-based automated design and planning for plumbing systems in residential buildings
This research develops an automated design and drafting system for the plumbing and drainage system for residential building construction. There are two scenarios for industrialized construction of residential buildings: (1) 3D volumetric, i.e., the building is manufactured in 3D boxes and (2) panelized system, i.e., buildings are manufactured in the form of 2D floor, wall, and roof panels. In both systems, the plumbing and drainage systems are drafted manually and installed in a manner that relies on trades knowledge and experience. The automated method proposed in our research can improve design efficiency, eliminate design errors, and reduce material waste compared to the traditional manual approach. In our approach, in order to improve production efficiency at the panelized construction plant, the plumbing pipe network is separated into smaller components as subassemblies coinciding with the geometric boundaries of the plumbing panel, which in turn corresponds to the floor or wall panel through which the pipes are to pass. Meanwhile, a BOM for each plumbing panel is generated for the purpose of further optimization of the cutting list. A prototyped BIM application, as an add-on to Autodesk Revit, is also developed. The key contributions of this research include the integration of the BIM model with the automated design system, the introduction of a rule-based pipe route planning approach, and the development of an optimal cutting stock algorithm to improve design and production efficiency.
BIM-based detailed estimation system
As the construction industry shifts towards automation and industrialized construction, and given that, in this context, construction processes are completed by automated machines in a production line setting, it is possible to estimate the production time and the associated cost with a higher level of accuracy. Additionally, with the rise of BIM applications in industrialized construction, a significant benefit is gained in terms of the data transformation between the phases of the projects. In this context, in the present research a framework for a BIM-based estimation system is developed to generate accurate and detailed production estimates based on the machine’s motion and the geometric information of the project, where the motion of the moving parts of the machines’ structures is investigated in order to calculate the speed and distance each part travels in a given cycle. The developed estimation system is also used for maintenance scheduling purposes to calculate the life cycle usage of each part in the machine.