Parametric modelling used to optimization

By using parametric modelling in manufacturing it is possible to optimize a building to be complex in its shape and use the optimal amount of material for the building The parametric design can be used in the design phase to investigate how the different parts of a product can be put together to give different kinds of solutions for the whole product. The parts can be varied to find the optimal solution. [1] One variable could e.g. be how large an overhang should be in relation to how big a window is and how much daylight is needed in a room without getting overheat. This could be investigated by running a daylight simulation connected to the programs like Rhino and Grasshopper, which connects the geometric data and the results from the simulation. It is here possible to change the size of the window and the overhang, and get the optimal sizes for the best daylight factor without the room to be overheated. In the BIM handbook chapter 2 it though said that it is not possible to link the data from a program like Rhino where the geometry is studied into the design development, because the object is not linked to the other objects. But I think that is because the book is from 2011, and with the connection to Grasshopper, it is namely possible to connect the data and use it in the design development phase. An example of how the parametric modelling can be used is described in the article “Solar analysis in Grasshopper” [2] 

It is also described in the BIM handbook that parametric modelling can be used to incorporate the knowledge from earlier designs and manufacturing processes, to find out what works and what doesn’t. It is again way optimize the products and get data that can be needed in design and production. 

I find these two examples of what parametric design can be used to very interesting. I think it a way for us engineers to be able to think more innovative and use our time more efficient. In stead of designing an overhang and a window separately, then do a daylight and a indoor climate simulation, and get a result where we have to change one parameter at a time, we can instead get the result quickly by using parametric modelling tools as Rhino and Grasshopper connected to the simulation tools. It is a way to easier do integrated design which I think will be even a bigger part of how we design our buildings in the future.  

[1] Eastman, Charles M. BIM Handbook : A Guide to Building Information Modeling for Owners, Managers, Designers, Engineers and Contractors. Vol. 2nd ed, Wiley, 2011.

[2] Danil Nagy, Solar analysis in Grasshopper, Feb 26 2017,  https://medium.com/generative-design/solar-analysis-in-grasshopper-5dae76c9b6cb

Alkiviadis Tsitsios: Interesting topic! I know that in Denmark BIM is integrated very much in the construction phase. A BIM tool for contractor called Dalux is very much used in Denmark. In this use it is possible to have 2D and 3D drawings, schedules, task lists, punchlists, safety reports all connected in one program on a smartphone or IPad. It think it shows that BIM is not just a tool for design, but many tools which can be used through all the phases of a building process.

Weiyi Tang: As you write in you post a newer and more efficient way of doing projects could be Intergraded Project Delivery. I do also very much like the thought of doing this kind of project instead of the traditional Design-Bid-Build delivery, but I know from an article that I once read that it is mostly the engineers how likes this method. The architects can feel that they are more limited in the design phase and that it takes too long time for them. Though I think that it is just a matter of getting used to the way of working closer together, and of course form a good team which can work together.

Jenny Fretta: By this blog post I think that it once again shows that BIM really is effective to the matter of having an overview a building and the different processes through the whole life cycle of a building. I think the way that the owner and facility manager can keep take of errors and the cost is very interesting also in terms of how a building can be more sustainable with lower energy use and thereby also lower cost.

B2: Chapter 2: BIM Tools and Parametric Modeling - Harvin Bhandal

In chapter 2 of the BIM Handbook, Eastman delves into different BIM tools and aspects of parametric modeling. He begins with the evolution of parametric modeling and its shift from 2D drafting to 3D modeling using computer softwares. The chapter discusses the importance of both predefined and user-defined rules in the BIM process. An object’s behavior is defined as “how [it] updates itself as its context changes” (in relation to defined rules). Each parametric object has certain attributes which makes it a lot more efficient to create and modify geometries. For example, a building element, such as a wall or door, is first defined by a class or family with rules that govern its parameters. As better put by Eastman, “Designing a building that contains a hundred thousand or more objects would be impractical without a system that allows for effective low-level automatic design editing”. 

In BIM application, the predefined objects and rules are mostly correspondent to existing design standards. For example, the standard practice for steel design is based from the AISC handbook. Eastman discusses certain scenarios where the industry standards cannot be used in the design model, and a designer has to create new objects. These scenarios include specific design conditions, aesthetic criteria, and new technology that has not been standardized yet. 

The chapter also compares different BIM platforms and discusses each of their strengths and weaknesses. Revit is the market leader in BIM software, and it is known for having user-friendly interfaces along with many useful development tools and libraries. As of now, I have no experience with Revit and I was a little apprehensive about having to use it in this class. However, this chapter emphasizes that the use of BIM platforms exist to make design tasks a lot less time-consuming and less error-prone. BIM has the capability to detect design clashes, which can alert the designer where changes need to be made. While Eastman states that often times it takes months to use a BIM design application proficiently, they are still very powerful tools and is necessary to use in many design scenarios. As the models are rendered in 3D, all parties involved in the project will have an easier time understanding certain components that may be difficult to interpret from a 2D drawing. Since the publication of this book in 2011, it appears that BIM has been growing as predicted and has had huge impacts on the ACE industry, saving both time and money for everyone involved.

Sources: 

Eastman, Charles M. BIM Handbook : A Guide to Building Information Modeling for Owners, Managers, Designers, Engineers and Contractors. Vol. 2nd ed, Wiley, 2011. EBSCOhost, http://web.b.ebscohost.com.ezproxy2.library.drexel.edu/ehost/ebookviewer/ebook/bmxlYmtfXzM2NDIzOV9fQU41?sid=bc728db5-ac2a-463a-be02-b1d1edcfc78a@pdc-v-sessmgr02&vid=0&format=EB&lpid=lp_71&rid=0

Comments to others:

To Alec Silverstone:

Alec, you present very good points and I agree that contractors should be involved, or at least informed of the design process. By providing contractors access to the BIM models, they will be able to get a better understanding of the project and see it in a 3D view. It also definitely would save time and prevent any issues by BIM’s ability to detect clashes. While it would be ideal that a contractor is involved in the design process, unfortunately I feel like many times that does not happen. During my first co-op, I worked at a construction claims consulting firm, and it was apparent that a lot of the issues that contractors encountered during the construction process (which invevitably caused the project to be delayed) was due to unclear designs and miscommunication. I think BIM has the potential to lower the frequency of these issues and make for a smoother construction process, especially if contractors are involved. 

To Christian Tait:

Christian, you highlighted a major issue that business and money can hinder the development of using BIM across different platforms. During my co-op, I always found it frustrating that it was not as intuitive to use files from AutoCAD and Microstation in tandem. While it's obvious that a company would only operate within its best intesest; ie making the most money, it is frustrating as a user that many programs do not work well together. Even though companies would claim there is no reason to have to interchange between programs, clients may have special requests for certain platforms to be used. Furthermore, users may be more familiar and proficient operating under a certain platform.

To Albert Hanan:

Albert, you did a great job discussing the evolution of parametric modeling and how it evolved into today’s uses. As I discussed in my post, the development of 3D modeling was a huge advancement and expanded the limits for design. The combination of the two classic modeling methods to produce the modern method truly shows how it is important to understand a product’s history in order to improve it. In this case, the best aspects from the CSG and B-rep method were combined to make modern parametric modeling both modifiable and easy to use. 

B2 - A brief history of Parametric Modeling

3D modeling has been in development since the 1960s. The need for 3D graphical representation was clear, and many potential fields were looking to benefit from it, including engineers, architects, filmmakers, and game designers. The first major step occurred in 1973 when the ability to create and edit solid 3D volumes was developed independently by various institutions. In the early stages of 3D modeling, two major forms competed for dominance: the boundary representation approach (B-rep) and Constructive Solid Geometry (CSG). B-rep represented shapes as a closed set of bounded surfaces which was set by the user, and built-in computational functions in place to allow these shapes to have dynamic dimensions. Commonly used shapes were built into the software (such as cylinders, cones, cubes, pyramids, etc.) but abstract shapes could be user-defined and then extruded or revolved. In CSG, a shape was represented as a set of functions combined through both algebraic and boolean expressions. The primary difference between CSG and B-rep is that CSG stored an algebraic expression to define a shape while B-rep stored the results of the user provided definition as a set of operations. While this may not seem like a significant difference on paper, because the methods had major differences in their back-end systems, they also had major differences in their capabilities. For example, in CSG elements could be edited and regenerated on command, while B-rep was better for computing mass properties of solids, rendering, and checking conflicts between objects.

Interestingly enough, it was eventually realized that these two methods should be combined allowing for editing within the CSG tree. By utilizing the editing capabilities of CSG and combining them with the visual benefits of the B-rep display interface, more complex designs could be made from compositions of basic shapes. Today, practically all parametric modeling tools use this combination for both editing and visualization. Without this innovation, modern parametric modeling would be impossible.

While seemingly unimportant, I think it is interesting to delve into the history of such a powerful design tool to help further our current understanding of the system and platform. Moreover, after knowing this information, I will surely keep it in mind and perhaps have a deeper understanding and appreciation of Revit as I begin utilizing and becoming more comfortable with the software over this term and in my upcoming co-op.

Comments:

Alec: Interesting post. I found your point about construction managers being involved in a BIM model and the design process before the build phase true to an extent, however, there is something to be said about why this isn't always the case. In AE 390, we learned about the "Integrated Design Process" which is a method building design wherein all major stakeholders and designers in a building (i.e. architects, MEP engineers, structural engineers, construction managers, contractors, owner) take part in the design process from day one. This is contrary to the traditional method of an architect being commissioned to design a building, drawing plans, handing them off to the engineers, etc. with little to no communication between these stakeholders. In general, it seems that the integrated design process yields more effective and efficient buildings as all systems are working in harmony, however, from people I've talked to in the industry, it seems that this method isn't always used because it slows down the design process significantly. Here's a video if you're interested in the integrated design process: https://www.youtube.com/watch?v=hIX-J83lmaI

Gabe: I enjoyed your reflection on the chapter--it was interesting to see another take on the same reading that I did. While I focused more on the history of BIM you seemed to write more about the functionality of BIM (ie how it works and how it detects errors). It also seems clear to me that learning about how BIM works enhanced your previous knowledge and experience with Revit, giving you newfound knowledge and a new perspective on a program you are already familiar with. As someone who does not have an extensive Revit background, I will make sure to keep your comments regarding the parametric capabilities of Revit in mind when learning and gaining experience.

Jenny: I liked your post. Your main point--that BIM can be used by managers to prevent collisions and/or construction issues before construction and thus save money--is one that is extremely important but could often be overlooked by engineers. Our peer, Alec Silverstone, brought up a similar point saying that using BIM for clash detection can not only save money, time, and effort, but also can keep managers and construction teams more involved and "in the know" on the design process, something that can help create a more efficient building and save money in the longrun. 

Sources:
[1] Eastman, Charles M. BIM Handbook : A Guide to Building Information Modeling for Owners, Managers, Designers, Engineers and Contractors. Vol. 2nd ed, Wiley, 2011. EBSCOhost, ezproxy2.library.drexel.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db=nlebk&AN=364239&site=ehost-live.