Minimum distance between two 3D objects? 1

[transmissiontowers]

Just getting into 3D drawing and have some square concrete piles driven at 15° angles near an old pile foundation with piles at 3:12 slope. I've managed to draw the old piles and new piles and their caps as 3D solid objects. I can move the 2 and use the INTERFERE function to check when they don't collide, but I would like to check and measure the minimum distance between two 3D solids (2'x2'x90' piles).

I looked around in the help but didn't see anything. Is there a lisp routine that will tell me the distance between them?

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I have been called "A storehouse of worthless information" many times.

 

[JeffTech]

If they don't touch but are angling towards each other (where rays would eventually intersect) then wouldn't the bottom be the closest?

Mayber you could check the distances on 2-d axis's and use some trig to figure it out?


Jeffery V C.E.T.

"If Brute force doesn't solve your problem, your not using enough"

 

[btrueblood]

Ugh. If you model them in Inventor it would show the minimum distance with a click of the mouse, using the measure tool. Dunno about Acad. I think you are stuck doing it the semi-manual way, as Jeff suggests.

 

[transmissiontowers]

One of our 3D CAD people drew it in Micro-station. I'm just the Engineer for the structure above the foundation and only dabble in ACAD and 99% in 2D up until now.

I was thinking I could draw a line perpendicular from one face and perpendicular to the second surface and then measure the length.

To answer JeffTech's question, the 2 pass each other at odd angles and do not intersect unless I move one group in relation to the other then I can see where they hit with the INTERFERE command.

I was moving the group 1 foot at a time to see where the collisions happen, then move another foot, and another until there were no hits. I continued to move it until I got another collision to the second pile, then I could tell where the range was where the no hits happened.

_____________________________________
I have been called "A storehouse of worthless information" many times.

 

[CarlB]

Couldn't you set a view that was aligned with one pile (z axis along t he pile axis), then measure the 2-d distnce to the nearest crossing pile?

 

[chicopee]

Your OP is a descriptive geometry problem. Get a descriptive geometry book and read the section dealing with the the shortest distance between two skewed lines (in your case the lines will be the piles)
The methology will require to have for example a front and a top view showing the two piles in skewed lengths; then concentrating on one view, you'll need to draw an auxilliary view showing the true length of one line (pile)and the second pile will still be skewed but orientated differently; another view developed from the auxilliary view will then be needed to show the true length view as a point but the second skewed line will remain skewed but again in different orientation. The shortest distance will be a line drawn from the point to a perpendicular position on the skewed line.

 

[transmissiontowers]

Well it's a moot point now. The construction coordinator decided it was too much risk to drive the new piles between the old piles and we moved the new group back another 50 feet so there was no possibility of them hitting. The pile driving contractor said they could do it like I wanted but they were overruled.

I figured I could have done some UCS views and done a measure to the skewed pile, but there are 4 groups and it is tough to see where I am. There is probably a way to cut a slice through a 3D drawing and show only a limited depth but like I said, I am very new to 3D.

And I guess I could have gotten a reference book like chicopee said and gone through the refresher course, but I was hoping there was some ACAD command that would do the trick for me.

_____________________________________
I have been called "A storehouse of worthless information" many times.