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nbennettwv wrote:

It would be very easy to model such a log and knots with 3Dsolid
entities, and then use the SLICE command to cut the assembly just as
with a saw blade: flitch-, rift-, or quarter-sawn as required. The knots
and the log would be separate entities, so care would need to be taken
to move the cut pieces as one. Perhaps GROUPing them after the cut would
be the most direct.

Alternately, after creating the model, you could use the SECTIONPLANE
command in (version 2007 and higher) to simulate the blade cut, and
choosing whether the removed portions would be ghosted or made invisible
as the plane is moved across the log.

Cool project. Readily accomplished. Let me know if this is something you
want to contract out!

-Bill

The fact is, you will have to know how to describe it with data and a logic process represented by code in some
language. Autocad can draw solids using the data and process.
I would guess that its ability to create solids by subtracting one solid from another, will be the thing that is of use
to you.
I think you will still have to work out the math of where cuts are to be made to avoid the knots, or minimize them to
some allowable diameter.

This gets close to what civil engineers do with roads. We define a centerline, then things along and off the
centerline. Then we do all kinds of tests when interacting with the user, to see if a point is within some area, then
we act accordingly.
Hopefully you have some programming experience, should be fun if so.

nbennettwv
|>I work in research for the USDA Forest Service and am trying to find a method to saw virtual logs into virtual boards. Roughly, virtual logs would be cylinders with knots represented by cones starting in the center of the cylinder and extending to the outer surface of the cylinder. The cones could be present at any angle around the cylinder. When a board is taken from the log it would be represented by a rectangle and would contain circles or ovals anywhere a cone was bisected. Is there any aspect of AutoCAD that could be utilized to develop this process? Thanks. Neal.
James Maeding
Civil Engineer and Programmer
jmaeding - at - hunsaker - dotcom

I see.
Now the first question is what format the data must be in, to work in the board grading simulators.
Are they looking at the shape of the board, or at the colors on the surface?

Once I know a more detailed description of what a virtual board is, I can suggest how to make them with AutoCad.

I totally see why all this is needed, its amazing stuff really!

nbennettwv
|>I am a mechanical engineer and am working with a computer scientist on this project. I designed and built a 3D laser log scanner that gives a topographic map of the outside of a log including most of the defects (knots,holes,splits). We have a large data base of these defects that were sliced from the outside of the log to the heart and measured. We can use this defect database to project the defect shape inside of the log based on what the scanner maps on the outside of the log. On the other end of the spectrum, several years ago we developed a large database of virtual boards. From this database we developed a program that grades the virtual boards by industry standards. More importantly, the computer scientist developed a couple of programs that cut up the virtual boards in the same manner that a manufacturing plant will cut up real boards. The wood industry uses these simulation programs to determine the optimum grade of lumber to make their products. These simulation programs
|>save wood and increases profits.
|>We are now at the point of trying to connect these two research areas. We need to devise a method of slicing the virtual logs into boards and then being able to use the boards in the board simulators. We have already discussed that our largest problems may be compatibility issues between anything that we accomplish with AutoCAD and the other programs. But if we are successful, we hope to be able to scan a real log and have a computer tell us how to saw up that log with least amount of waste.
James Maeding
Civil Engineer and Programmer
jmaeding - at - hunsaker - dotcom