2) Parametric Object Modelling

Question 1

What are the types of Solid Modelling?

2 points

Answer 1

Boundary Models (B-rep - boundary representation)

Construction Models (CSG - constructive solid geometry)

Question 2

Describe the 2 types of Solid Modelling?

Answer 2

Boundary Models (B-rep)
Solid body described by its directed surface.
Inside, model has defined the material - but model is hollow.

Construction Models (CSG)
Basic solid shapes - combined using Boolean set algebra (union, intersection, difference

Question 3

Explain the hybrid model idea (relating to Solid and Construction modelling.

Answer 3

Combined approach to design - hybrid between B-rep and CSG.

In BIM we need solids and definitions of a surface.

Question 4

Definition of Parametric modelling?

Answer 4

The creation of a digital model based on a series of programmed rules/algorithms – Parameters

Question 5

What are the degrees of Parametric modelling?

3 points

Answer 5

Parametric Solid modelling;

Parametric Assembly modelling;
Assembly of individual parametric objects - calling in instances and specifying parametric relations between them.

Topology-based Parametric modelling;
Embedded complex intelligence into parametric model - e.g. sliders in dynamo.

Question 6

Define;
Category
Class/Family
Type
Instance

Answer 6

Category; e.g. Column

Class; e.g. Round/rectangle

Type; Dimensions

Instances; Positions/relationships with other parameters.

Question 7

Define LOD

Answer 7

LOD = Level of Development, Definition or Detail - description of graphical content of models at each stage in the project.

Question 8

What are the 6 levels of development of the LOD classified (named) as;

Answer 8

LOD 100 - Graphically presented in model with symbol
(Example - Column)

LOD 200 - Graphically presented with approximation of quantities, sizes, shapes and orientation
(Example - Steel Square Column)

LOD 300 - Represented in Model as specific system, object or assembly, with accurate parameters
(Example - 300 x 300 Steel Square Column)

LOD 350 - How specifically designed column ineracts with other building systems.
(Example - 300 x 300 Steel Square Column in situ)

LOD 400 - Detailing to column construction, assembly and installation
(Example - 300 x 300 Steel Square Column with detailing, fabrication, assembly and installation information)

LOD 500 - Column has been built and updated in the BIM model
(Example - 300 x 300 Steel Square Column as built, field verified representation).

Question 9

Define LOI

Answer 9

Levels of Information - non-graphical contents of models at each stage of the project (e.g. cost)

Question 10

What is the nameof the UK and Americas LOD description?

Answer 10

AIA - American Institute of Architects

PAS 1192:2 - British

Question 11

How does AIA and PAS 1992:2 differ?

Answer 11

AIA is more structured

AIA doesn’t have the link that PAS 1992:2 has between the project stages

Question 12

What are Object libraries?

Answer 12

Object libraries are where object families can be downloaded - so final object choice (e.g. specific type of chair) can be seen in the model.

Object libraries are provided by the manufacturer to be able to download.

Question 13

Do any Standards require object libraries to be designed a specific way?

Answer 13

Yes. PAS 1992:2 says that the object families in the object library have to be provided in a format that can be downloaded and used in any BIM software.

Question 14

What is Uniclass?

Answer 14

Uniclass = Unified classification for the UK industry covering all construction sectors.

Classifies objects in order to use later on in schedules/drawings.

Question 15

Why is it important to use Uniclass ?

Answer 15

Makes obejcts understandable and useable for all.