BILT Speaker

BILT Speaker
RevitCat - Revit Consultant
Showing posts with label Swept Blend. Show all posts
Showing posts with label Swept Blend. Show all posts

Saturday, 13 April 2019

Revit Conceptual Massing Environment - Index


Over the years I have struggled with the Conceptual Massing Environment (CME) in Revit.  It is not easy to use, and is not at all well integrated with the rest of Revit.  However, I have learnt a huge amount about how to get it to do what you want (or not!).  I have tried to document some of the tips and tricks on this blog and during various conference presentations that I have given at RTC & BILT .

Here is a summary / index of all the relevant posts on this blog:

Conceptual Massing Environment

Rival Revit Environments - Traditional vs Conceptual Massing Environment (CME)







 

Creating Traditional Forms using Conceptual Massing

Part 1 - Extrusion 
             Extrusion Offset Properties
Part 2 - Blend
Part 3 - Revolve
Part 4 - Sweep
Part 5 - Swept Blend
Part 6 - Loft
 
Part 7 - Hybrid Swept Blend / Loft


Revit Nurby Forms at BILTANZ

Adaptive Components

Adaptive Components

Adaptive components are a subset of the Conceptual Massing Environment:

Repeaters

Repeaters are a kind of array, in the CME world . . .

Modelling Santiago Calatrava's Gare do Oriente (Lisbon) using Repeaters:
Step 5  Assembling the Array of Structural Columns



Revit Ideas - Vote to Improve the Conceptual Massing Environment in Revit:


Some of the problems could be alleviated by the following capabilities - please vote for them on the Autodesk Revit Ideas wish-list if you agree:



Saturday, 25 February 2017

Gare do Oriente - Revit Nested Repeaters - part 3

In previous posts I described how to use Revit adaptive components and repeaters to start creating a model of Santiago Calatrava's roof structure of the Gare do Oriente in Lisbon:
Part 1 - The rig for one structural column
Part 2 - Placing roof panels onto the rig

This time we will look at creating the structural elements to put on the rig.




Here is a youtube tutorial on creating the structural elements as an adaptive component, and placing the adaptive components to become a 'Repeater'

Steps

Here is a quick checklist of steps required:
  • Start new adaptive family
  • Place a point at the origin, plus two more points
  • Make the points adaptive
  • Join all three points with reference lines, ensuring that 3D snapping is ON
Add an arc between points 1 and 3;  the arc must be kept planar with the 3 points, so it needs to be hosted to a rig (or alternatively a plane - not shown here)
  • Place a hosted point midway along the line between points 1 and 3
  • Place a reference line from that hosted point to adaptive point 2
  • Place another hosted point on that new line
  • Place a reference arc by Start-End-Radius, snapping to adaptive points 1, 3 and then to the latest hosted point
Create a curved swept blend along the arc:
  • Place two more hosted points close to each end of the arc
 
  • Create a new profile family from a generic adaptive template (not a traditional profile family template)
  • It does not require an adaptive point
  • Draw a 2D profile closed shape on the level work plane - in this example a T-shape
  • Dimension it and make it parametric
 
  • Save and load into the first adaptive family
  • Place a profile component onto each of the hosted points on the arc
  • NB. The reason for hosting the profiles onto points that are themselves hosted on the arc is that it gives much better control:  The points have rotation parameters as well as parameters to control their distance along the arc - required to vary depending on the structural connections. Hosting the profiles directly on the arc would not give those controls.
  • Duplicate the type of the profile component closest to adaptive point 1
  • Make its dimensions larger
  • Select both profiles plus the reference arc 
  • Create form
  • It will generate a swept blend that tapers to a smaller size towards point 3 
  • NB. For more detail on this procedure, refer to my post on Adaptive swept blends
Create a simple extrusion family
  • Create a new family from a generic adaptive template
  • Place two points (one at the origin)
  • Make them adaptive
  • Place a reference line between the points 
  • Host two points close to each end
  • Associate their 'Segment or Chord Length' properties to parameters for offsets from ends
  • Make the reference planes of the points always visible
  • Set the Work Plane as the reference plane of one hosted point
  • Draw a profile for the extrusion - I just made it a simple circle
  • Give it dimensions and associate to parameters
  • Repeat the same profile on the other hosted point
  • Select both profiles and the reference line
  • Create Form
  • Save the family - I like to use a code to indicate it is adaptive and how many placement points
    eg:  AC 2pt Tube
  • load it into the first adaptive family
  • Place one of the new extrusion components between adaptive points 2 and 3
  • Associate its properties to parameters in the parent family as desired
  • Flex the adaptive points to check it is all working

 This structure now requires an additional placement point in a different plane to the rest
  • Add another point close to point 3
  • Make it adaptive (4)
  • Move it down in the Z direction
  • Link points 2 and 4 with a reference line (optional)
  • Link points 3 and 4 with a reference line (optional)
  • Place one of the tubular 2 point adaptive components between points 2 and 4 
  • Place another between points 3 and 4 
  • The structure family is now ready to use
  • Save it and load it into the rig family created in part 1 - The rig for one structural column

Assembling the structure on the Rig

  • On the rig, add a new hosted point onto the vertical reference line - this represents the springing point of the structure where it starts to curve out
  • Below this will be a rectangular extrusion, to be added later
  • This point will host the base of the structure adaptive components
  • Change its Measurement Type property to segment or chord length
  • Associate its segment/chord length to a parameter for Height of springing point
 
  • If you have the roof panels already in place on the rig (Step 2), it will probably be easier if you temporarily hide them before starting, to make snapping easier.
  • Place one of the support adaptive components, making sure to snap the 4 placement points onto the rig in the right order:
    1. Springing point
    2. Central valley hosted point on vertical line
    3. Divided path point on inner circle (orthogonally, along X axis from origin)
    4. Divided path point on outer circle, one division around anti-clockwise
Array a pattern around the circle using the Revit Repeater function:
  • If you select just the one structural element and repeat it, you get a straightforward radial pattern - this is not what we want (so, undo it)
 
  • We need to teach Revit how the array pattern should go - so you have to place a second structural component:
  •  Place another adaptive component 90 degrees around the circle in the same sequence
  • The first two placement points go onto hosted points that are already occupied by the first structural component - so it is vital that you snap to the host points, and not to end points or adaptive points on the component.
  • Watch the prompt in the bottom left corner of the screen before each point placement - the first two should be to Point of Reference points
  •  The second two should be onto Point of Divided path
  • Use this technique for every subsequent placement of adaptive points - it gets progressively more tricky as you go
  • Select the two adaptive structural components
  • Click on the Repeater icon
  • You should get the desired pattern if all adaptive points were hosted correctly.  
  • If not you may be able to rehost the points (if you can guess which one is wrong!) - or just delete the adaptive component and place it again
  • The next step is to place two more structural components in the reverse direction (clockwise)
  • You could try placing them to the correct hosts, but it is really difficult with all those elements in the way - so it is easier to temporarily hide the repeater first
  • You may find that when you hide the repeater, the nested tubular components around the top do not hide.  In which case, you need to select one, then right-click to select all instances and hide those too
  • Once placed, the two new structural components will fit in the gaps between the first repeater element
  • Some of the structural members will be in the same place as the original ones, so you may get a warning message about identical instances.  
  • If this is an issue (for scheduling etc), then you will need to go back into the adaptive structural component and give the common elements a visibility instance parameter - back in the rig family, you can then switch off the duplicate structural members on the two newly placed components.
  • Select the two new components and array them using the Repeat function
  • Now the basic structure should be complete

  • Try flexing the parameters for the rig dimensions to check that the structure moves with it.
  • If you have the roof panels already placed, make them visible again to check that it aligns correctly


Click below to proceed onwards:
Step 4  Adding Struts to the structure
Part 5 - Assembling the Array of Structural Columns

Sunday, 12 May 2013

Swept Blend using Profiles in Adaptive Components

This process might seem obvious to anyone who regularly works in the Revit Conceptual Massing Environment (CME), but for those who are starting out with Adaptive Components, it might help the transition from the old Revit family environment.

The question is:
How do you create a solid extrusion or sweep using a profile in an adaptive component ?

A lot of people advise against nesting components too much, but profiles are incredibly useful in Revit - they can save a lot of time and usually give much better control of geometry, rotation and parameters than just drawing linework within a family.  But the problem in adaptive components is that Revit won't allow you to load a traditional Revit profile family.  The adaptive component environment also does not have any of the "Edit Path", "Load Profile" sort of commands that you regularly find in the family editor.

The Solution:

How to create a Swept Blend using Profiles in Adaptive Components

The answer is really quite simple:  create an adaptive component that just has 2d linework geometry.  It can have dimensions, parameters and reference planes just like a profile.  the main difference is that it is visible in 3d in editing mode and after you have placed one too.





There are a number of tricks that you need to know:

  • The adaptive "profile" component does not need to have an adaptive point.  In fact it is better without, because then you can use the reference planes to lock the geometry to the origin as in a normal profile.
  • When you place an adaptive profile into another adaptive component, you can place it on a workplane or host it onto another element.  If you host it to a reference line it will automatically orient itself to be prependicular to the line (or arc).
  • You can also host it on a point, which may itself be hosted on a line - very useful for controlling its location along the line parametrically.
  • You can host it on a divided path node;  but don't bother to convert it to a repeater because it cannot then be used to create a solid form.
 Here is a quick description of how to use profiles to create a swept blend, but this technique could be used for any shape, solid or void.



  • Host two different size adaptive profiles (different types) on an arc reference line;

  • Select the profiles and the arc;  
  • Create a form;


  • Select a profile and slide it along the arc;

Flex the form by changing the sizes of the profile, the radius of the arc or move the adaptive points.

This techniques features briefly in my upcoming RTC presentation:
"Fractal Fun with Revit Repeaters and Adaptive Components" at RTC 2013

Creating a more Complex Form

You could try something a bit more complicated by first applying a divided path to the arc

Then try hosting some different sized profiles on the divided path nodes
You can turn these into a repeater - but sadly you can't select a repeater and turn it into a form (Revit won't allow that as of v2014 *see below)
The alternative is to manually host the profiles on each node - the end result may look the same, and be more laborious but it is not a repeater
These manually placed profiles can all be selected and turned into a form
The profiles are still visible, but they can be hidden
This form can be somewhat parametrically controlled - spacing of nodes, profile sizes, arc radius etc;  but the number of profiles cannot be adjusted after the fact.

Addition to Post  20 Dec 2013
I notice that this post gets a lot of hits so it must be an issue that people struggle with on Revit.  So I thought I'd add a bit more information:

It is possible to use a traditional Generic Model family with flat geometry nested into an adaptive or mass family to create your sweep or lofted form.  However, a traditional generic model does not have the advantages that and Adaptive Component (Generic or other category) has:

  • When a traditional generic family is loaded in, it will normally just place flat on the Level work plane.  If you want it to be in a different orientation, you need to set its properties to not be always vertical, and also to be work plane based.  Then you have to stuff araound setting the work plane before placing it - what a hassle.
  • If you use an adaptive component (with 2d linework, preferably in a closed loop), you don't need to mess with its settings - just load it into the adaptive or mass family;  when you place it, it will automatically rotate to its host - either perpendicular to a line, or snapped to a point.
  • If the point is in free space (ie not hosted on something else), it will snap to the default work plane of the point (most likely horizontal)
  • If the point is hosted on a line/arc/curve (it will look smaller than a free point), it will again orient to the default work plane of that point - but that will already be oriented perpendicular to its host.  Its very easy.
  • Another advantage of placing the adaptive profile onto a hosted point is that the hosted point has a "Rotation Angle" property that is simple to control - the profile will rotate with it.  simple.


You can use the Rotation Angle property of your hosted points to rotate individual profiles to achieve a twist in your form really easily.

Postscript 11 June 2015:
What happens if you want to create a hollow section sweep?  Refer to this post.

In Revit 2016, you can now create a swept blend or loft from a repeater (sort of) - refer to this post