I would like to enter into solidworks a rib shape using the XYZ curve tool...ive included the rib shape with dimensions....does the above information apply to this also...Ive tried to enter the dimensions into solidworks manually but I get modern art and not a rib shape...so I~m doing something wrong...is there a good write up on this xyz tool to understand it better. I`m a little baffled how the xyz numbers relate..
Thanks
Last edited by North_roll; 06-25-2020 at 07:27 PM.
North_roll(real name would be nice)-
Normally airfoil data is in terms of 0 to 1 from nose to tail, with the Yu(pper) and Yl(ower) either given as shown,
or with Y +/-.
SolidWorks' convention in general is that [+X is left], [+Y is up], and [+Z if fwd].
So if you look normal to the right plane from the left, the origin is zero, with -Z going right, and +Y is above the Z axis
and -Y is below.
If you specify the nose of the airfoil at Z=0, the TE will be at Z=-1
The Curve through XYZ are cartesian coords with the above SW convention.
Using the tool to draw an airfoil, you specify the Upper TE coord, progressing along the upper camber forward.
In other words: (set X to zero for all coords and disregard)
For the airfoil coordinate pairs: Z starts at -1 and and the corresponding Y values increase from near zero to max upper camber and then Y values decrease to 0 as Z approaches 0 at the nose,
where normally Z and Y=0.
Continuing on around below the nose, Z again moves back toward the tail increasing(?-decreasing) to -1 again,
while Y increases in the negative with a maximum value a maximum lower camber until it approaches near 0 again.
A careful reading (many times?) of the above description and you should understand.
So converting the numbers from the ZA plans, the SW coords are as follows:
(You could imagine those numbers as X,Y on a standard graph from the parentheses),
but they have to be in the order they are below for the Curve thru XYZ to lay on the R Plane.
Also, since your AF is not '1' long, you will start at Z=0 for the front rib rear and end at Z=499 for the front.
In the case of your numbers, assume 499 = '1' for Z
Your Fwd rib becomes:
X Y(vert) Z(horz)
0
-90
0
0
-89.5
100
0
-86
200
0
-77
300
0
-71
350
0
-61.8
400
0
-56
425
0
-49
450
0
0
499
0
49
475
0
71.5
450
0
87.7
425
0
100
400
0
119
350
0
131.2
300
0
144
200
0
147
100
0
148.5
0
Study how the numbers are translated from the plans chart.
After the curve is generated, you must 'project' it on a sketch on the R plane.
For the rear rib:
X= all zero
Plans X=SW Z
Plans Y=SW Y, with upper = positive
and lower = negative
It takes about 1 minute to enter into Excel, but since it is not continuous, you MUST do a separate sldcrv for each curve.
(Don't forget to use a metric template in SW)
So:
Normal X,Y
Y
X
Y
X
SW Y,Z
Y
Z
Y
Z
0
148.5
0
0
-90
0
0
145
-100
0
-89.3
-100
0
137.5
-200
0
-84
-200
0
127
-300
0
-74
-300
0
114
-400
0
-30
-622
0
96.5
-500
0
77
-600
0
72
-622
The section specified as straight appears negligible to me compared to the SW spline.
The SW file is available for study here: https://drive.google.com/file/d/1BG3...ew?usp=sharing
You must pay attention to the operation of whether the numbers are positive or negative.
-Christian
I think I am having some difficulty with getting the airfoil to scale down so the airfoil has a 63" chord (..or 63% from what i am reading here).
I am trying to make it so I can make a layout for making new ribs for my project and want to be able to mark out where the spars and stringers will be positioned.
I am new to Solidworks, so it's sometimes hard to understand what to do.
rkirk:
If you review the my post from 06/25, using an 'x' scale of 1 for LE to TE will generate an airfoil 1" long; then you scale it up by a factor of 63 which will make it 63" long LE to TE.
It is unclear where you are lost. Please review my detailed previous posts in this thread and try to duplicate them. There is even a 'pack n'go' of the files to download to step through
the procedure.
-Christian
Last edited by vondeliusc; 08-17-2020 at 12:47 PM.
I have reviewed this / your previous post and have read them carefully, and know this is a VERY easy operation to someone like you but I am a blithering idiot when it comes to SW.
How do you use an "x" scale and increase it to 63"?
How do I project the splines?
I am lost and I am sorry if this seems like common sense to you.. but it's CLEARLY NOT for me.
Using Curve through XYZ Points
Originally Posted by rkirk77
UPDATE : I think I've got it.
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