Thursday, July 10, 2014

Modelling MBS 1: The Hotels



I came to Singapore in 2007 to work on the Marina Bay Sands project.  the building was designed by Moshe Safdie and Associates.  Moshe assembled a very talented and dedicated team of designers to put all the pieces together.  The design for the forms was done in late 2006 into 2007 using Rhino, 3D Max and Maya.  At the time, Revit had yet to introduce the conceptual massing environment.  I've often wondered what the process for generating these forms would have been like had it been done using the more recent capabilities of Revit.  So i did some studying...

Let me be clear at the outset that i don't intend to get these exactly right.  I know there was considerable effort, deliberate nuance and extraordinary care that went into the development of this design.  My intention is to use the forms as examples for a lesson in how we can use Revit's conceptual massing in the form-finding process.

Part 1: The Hotels

As you can see from these images, the hotel towers are dynamic and morph in all directions as the rise up.





To try and replicate the geometry, the first thing I did was make a rectangle in the conceptual massing environment with key parameters controlling thickness, left & right offset and the shift from the main axis.  All of these are INSTANCE parameters.


The next step is to take this profile and nest it into a new conceptual mass family containing 4 levels.  Paste the family to all three levels.



After linking parameters to all the profiles, I created the forms, one for the "City" side, one for the "Ocean" side.



And now the fun can begin!  Tweaking the parameters like so:



will yield the following results:





Not bad for a start...but because of the way Revit joins geometry, the top portions of the tower aren't straight.  I don't think Moshe would have settled for such wacky wobbly BS, so lets try another way with an extrusion and some reference points.  Aiming for better control.  First, the profile:


and the parameters:



Nest it into my family and make the forms:



And we are cooking now!  The wacky wobbly is gone!



Now to add some voids to cut the edges.  First i place a reference point on a plane which has been constrained relative to the length of the towers.


I used offsets linked to given dimensions to setout a bunch of other reference points which in turn makes the profiles for cutoff voids.



After making them into voids:


Booyah....




parameter list for the finished product:




and a link to download the family:

https://drive.google.com/file/d/0B101ixgLlSGXbXBfNmd1cHh4V2c/edit?usp=sharing

man... its nice to be behind the wheel again.

Monday, November 19, 2012

Schedule Simulation Using Phases - The Poor Man's 4D Timeliner

I have been doing alot of work lately providing supporting graphics for construction bids.  Sometimes the rain-makers like to show potential clients the sequence of how the building/site will go together.

Rarely do we have the time for a full 4d navis works animation with cranes and all that.  Actually having adequate documentation to support such an effort is even less likely!  I came up with this B.S. modelling approach based upon a presentation by Aaron Maller at AU 2011 about phases, links, groups and design options.

Sooooo...how did i do this in Revit in one day?





 Pretty simple actually.

First off, I built a simple model and applied the site plan as a decal to a base plane.  This involved saving the pdf as a jpeg, pretty simple in ADOBE.

Then the real work started.  I had to liaise with my scheduler.  I gave him an excel spreadsheet indicating the different parts of the model that could turn on and off.  The scheduler then informed me the timing and durations of the various activities.  I rationalized it all so that I could take snapshots of the construction at 2 week intervals.



Then I went into my Revit model and created phases for each interval in the schedule


This part gets tricky.  i created a phase filter called "Timeline" specifically for the task at hand.  I probably could have used "Show Complete" but I like starting fresh in case i need to tweak things.


After settling on a 3d camera view I liked, I locked the view and set the view template.  Then i copied it a bunch of times, one view/snapshot for each phase.

 
 Now it just gets tedious...follow this step by step:

  1. Work in an default 3d view, not one of your snapshot views.  Make sure phase filter is setup to "Timeline"  Set the default 3d view's phase to the final phase, in this case "Phase 14"
  2. Make sure the model is finished
  3. Assign materials to the "COMPLETE" elements
  4. Change the construction phase setting for all these elements to the final phase, in this case "Phase 14"
  5. Copy all the elements off to the side a memorable distance like 1000m
  6. Create a material to represent a "CONSTRUCTION" phase.  In this exercise, I chose transparent red
  7. Assign the "CONSTRUCTION" material to all the copied elements
  8. Change the phase of all the copied elements to to the initial phase, in this case "Phase 1", they should all dissappear
  9. Change the default 3d view phase to the initial phase, in this case "Phase 1".  The red "CONSTRUCTION" elements should appear, while the "COMPLETE" elements go away.
  10. Move your "CONSTRUCTION" elements back into place.
  11. For all "CONSTRUCTION ELEMENTS", change the "Phase Created" and "Phase Demolished" variables according to the grouping in the schedule spreadsheet.
  12. For all the "COMPLETED ELEMENTS",  change the "Phase Created" variable according to the grouping in the schedule spreadsheet, while setting the "Phase Demolished" variable to none.

Now you can check each of the snapshot views to make sure they look right.


To generate the images, i used the INTERACTIVE RAYTRACE display option.



I let it process for about 1 minute per shot.  then i stopped and saved the image.  Revit will save the picture to the RENDERINGS folder in the project browser.


Export all the images as you would for any jpeg renderings.  Then i compiled all of them into an animated GIF file.  Instructions for this process can be found here:

HOW TO MAKE AN ANIMATED GIF

And thats it....enjoy.  See y'all at AU.

Wednesday, October 10, 2012

Rhino to Revit in 47 Easy Steps

I have yet to find the magic button or transfer format which will bring a form generated in Rhino into Revit, and allow for the application of any Revit functionality.  The only ting i have found which works is ingenuity, tenacity and reference points.

So they came to me with this:
And said "lets rationalize the geometry and explore joist spacings and make structural drawings for this roof"

I'm not a Rhino guy...I know that it is a mighty program and plug-ins like grasshopper, salamander & polar bear extend it even further, but I am just not that capable....I knew I could recreate this in Revit faster than learning Rhino.  So here we go.

The first thing to do was bring the model into ACAD and setup the layout circles and cut lines which would govern the geometry in Revit, starting at the topmost form.
You will notice many small circles placed at positive Z values.  These have been placed at the heights described in the original architect's model.  The reason to use circles is that REFERNCE POINTS snap to circles really nicely in Revit.

Also if you look closely, you will see that all the arcs are split up as well. this will make it much easier for me to create the individual surfaces later in the process.

So i bring my completed "Guide-line DWG" into the Revit conceptual massing environment:
With these guidlines in place, recreating the geometry is quite direct.  First i place the REFERENCE POINTS in all the circles, then i select them 3-at-a-time and push the CURVE THROUGH POINTS button.
Then i pick the pairs of lines for the top and bottom of each surface until the roof forms are complete:
The work so far took me an afternoon.

Now that i have the basic geometry in place, I can start using the DIVIDE SURFACE tool to find the joist lines according to whatever spacing is desired:
But if you look closely, its not "perfect".  the design calls for the joists to match 1-for-1 at the ridges of all the roofs, and this most assuredly doesn't:
Playing with both the BELTLINE parameter and the number of segments for a selected divided surface, i could get the arrangement 'perfect'
To cut to the chase, when i bring the form into the project environment, I can start adding structural elements and get to all the juicy good stuff:
It took me about 2 days to input the rest of the base geometry:
 And divide all the surfaces:
 Then i could ship it back to ACAD to generate a DWG file:
And with the wire frame in-place, we could pass the whole arrangement into analysis.
Happiness....joy in the kingdom....and 3 days later I quit that job.