Workshop 4 Notes

COMPUTER AIDED ARCHITECTURAL DESIGN

Workshop 4 Notes, Week of September 23, 2012

INTRO TO SURFACES, FEATURE SOLIDS, ACS AND ACCUDRAW REVISITED

1. SURFACES

Load the file Classes\Arch3410-6410-Mark-F11\Examples\surfaces\surfs.dgn. In the Surface Modeling Task list, retrieve the tool boxes associated with icons labelled "E" and "R" below, and use the tool specified in each case of a surface type entity as indicated below.

Surface and Solid of Extrustion

Select Surface by Extrusion from the task menu (T2 below)

Select the rectangle in the upper left hand corner, and ineractively extrude it along the Z axis.

Select Solid by Extrusion from the task menu (G2 below)

Select the rectangle in the upper left hand corner, and ineractively extrude it along the Z axis.

Note the solid by extrusion is filled in, wheras the surface by extrusion is an open container.
Select the Surface by Edge Curves tool from the Surface Modeling task menu.

Select in clockwise or counter-clockwise order the four edges assocaited with the figure below, then enter two data points in the view window away from the existing elements, one to generate and a second to accept the edge define surface.

select edges generated edge defined surface

The same tool applies to two parallel edges. Two initial cuved bspline established the edges used to generate the figure below. Each one of the initial bspline edges was selected to the same side of their respective mid-points, then two data points were entered in the view window away from the existing elements, one to generate and a second to accept the edge define surface.

Surface and Solid of Revolution.

The Surface of Revolution is select from the menu item T2. The profile curve is selected first, followed by end snaps onto the vertical axis line. With the dialog box indicating an angle of 90 degrees, the surface is swept out in four stages


Selecting the profile curve and the upper and lower portion of the vertical axis sweeps out 90 degree surface	Enter a data point off the geometrical elements to sweep out next 90 degrees of surface.

Enter a data point again to sweep out the third 90 degree surface (= 270 degrees).	A fourth data point will sweep out the full 360 degrees.

Similarly, if the Solid by Revolution tool is selected (submenu of G2), then a solid rather than surface geometry would be swept out.

The same technique also applies to a an open profile curve.


Selecting the profile curve and the upper and lower portion of the vertical axis sweeps out 90 degree surface	Enter a data point off the geometrical elements to sweep out next 90 degrees of surface

Tubular Surface

A tubular surface is obtained by the use of the Surface by Extrusion Along Curve tool.

The first option for this tool is used in the case of simple line along the ground and a 3D profile curve. Select the profile curve, the horizontal line along the ground, and then enter a data point in the view window to accept the sweep of the surface.


dialog box settings	preexisting condition

select profile curve and then horizontal line along ground to generate tenative surface	accept with left mouse button data point to yield this final result

Skin Surface

A similar tool is used to generate a surface along a profile curve between two end curves.

The cases below involve the use of similar techniques of sweeping two curves along a profile curve.


the Sweep Two Along One option is selected	select the profile curve

select the end curves	enter an additional data point to accept the generated surface

The Sweep Two along One option also selected for each of the two cases above	select the profile curve, and then select the end curves in each case, enter an additional data point to accept the surfaces

A variation on this type surface involves sweeping two curves along two curves.


	select the profile curves

select the end curves	enter an additional data point to accept the generated surface

The above operations produce the following result:

surfaces rendered in wireframe surfaces rendered in phong shading

2. FEATURE SOLIDS OR SMART SOLIDS

Create block with the Slab Feature tool from the Feature Solids Menu

Enter Holes

Move Holes

Modify Dimension of Holes

Modify Edges With Blend Feature

3. SIMPLE SADDLE REVISITED (FROM LECTURE)

1. With ACS Plane Lock set to On, Create a 12 x12 rectangle (place block tool) in the ground plane.

2. Using the "F" front Accudraw rotation plane, create vertical lines in opposite corners at 7 and 11 feet high each.

3. In the Sufaces Menu, generate a surface from four corner points.

4. In the Feature Solids menu, thicken the surface 1.0 feet.

5. Add a hole to the center of the new solid, using the same methods applied to the slab above.

6. Copy the hole using the Move Feature tool, using the same methods applied to the slab above.

7. Change the dimesions of the hole using the "Modify Solid or Feature" tool, using the same methods applied to the slab in the earlier example.

8. The same "Modify Solid or Feature" tool can be use to thicken the simple saddle roof.

4. . ACS and ACCUDRAW

ACS and ACCUDRAW are two inter-related but two distinct ways of establishing construction planes. The ACS, Auxilliary Coordinate System, is set into place on a more continuous basis and can be moved into any location and orientation. ACCUDRAW, a consturction plane compass, is set into place on a more transitory basis, and can be very quickly rotated and setup in relationship to the the active ACS. The combination of both systems affords quick and contextually sensitive options to build construction planes as needed.

ACS = Auxilliary Coordinate System. The ACS is the active construction plane, a two dimensional plane on which you create data points.
ACCUDRAW = The Accudraw Compass. The ACCUDRAW compass is a construction plane that is defined in relationship to the ACS. It is accssible through a set of QUICK KEYS (e.g, "F" - front, etc.). By default, it is co-planar with the ACS.

5. ACCUDRAW AND AUXILLIARY COORDINATE SYSTEM (ACS) REVISITED

1. 2d plane rotate 90 degrees on any axis (draw circles, arcs, etc.) (QUICK KEYS: "RX", or "RY", or "RZ")

Enter the first data point on the current Accudraw construction plan, enter the letter "O" for offset, and then use one of the following quick key combinations to rotate Accudraw around the x, y, or z axis:

Accudraw via "RX" key transforms to rotation of 90 degrees around x-axis.
Accudraw via "RY" key transforms to rotation of 90 degrees around y-axis.
Accudraw via "RZ" key transforms to rotation of 90 degrees around z-axis.

2. Menu item utilities/auxiliary coordinates for ACS options:

2.1a The current ACS can be saved under a named identity with the "Create new ACS icon"

2.1b Alternatively, save “base” (default ACS) via Accudraw by selecting Accudraw dialog box and using the quick key combination "WA"

2.2 Redefine ACS (three point method). Note that the red and green arrows are rotated into the new position.

2.3 Similar to example 2.1, we can use the save the current ACS as “shed":

2.4 Double-clicking on “base” restores the ACS "base":

2.5 Alternatively, using Accudraw, the quick key combination "GA" restores ("gets ACS") the ACS "shed":

3. ACS via TOOLS Menu

Menu item tools/auxiliary coordinates obtains a separate dialog box thatalso allows the following ACS operations:
icon 1: define acs with element (select front rectangle of cube, fix acs to it.

icon 2: define acs with 3 points (on face of cube)

icon 3: align acs with view
icon 4: align with attached reference file (skip)
icon 5: rotate it by value
icon 6: move it (if time)
icon 7: select ACS (similar quick key "GA”)


surfaces rendered in wireframe	surfaces rendered in phong shading