How do I enter a parametric equation in x, y, z into the equation editor. Is there a particular format that works? How about for r, theta, phi or r, theta , z?
How do I enter a parametric equation in x, y, z into the equation editor. Is there a particular format that works? How about for r, theta, phi or r, theta , z?
Mike,
I don't use equations, so I'm not going to be of much help, but perhaps my answer will prompt someone more knowledgeable to kick in.
What do you mean when you say parametric? I have seen people set up equations like x=f(t), y=g(t), z=h(t). Is that what you are referring to?
I don't believe SolidWorks knows about spherical or cylindrical coordinates, only Cartesion.
Jerry Steiger
Is this what you are looking for?
Operator  Name  Notes 
+  plus sign  addition 
  minus sign  subtraction 
*  asterisk  multiplication 
/  forward slash  division 
^  caret  exponentiation 



Function 


sin (a)  sine  a is the angle; returns the sine ratio 
cos (a)  cosine  a is the angle; returns the cosine ratio 
tan (a)  tangent  a is the angle; returns the tangent ratio 
sec (a)  secant  a is the angle; returns the secant ratio 
cosec (a)  cosecant  a is the angle; returns the cosecant ratio 
cotan (a)  cotangent  a is the angle; returns the cotangent ratio 
arcsin (a)  inverse sine  a is the sine ratio; returns the angle 
arccos (a)  inverse cosine  a is the cosine ratio; returns the angle 
atn (a)  inverse tangent  a is the tangent ratio; returns the angle 
arcsec (a)  inverse secant  a is the secant ratio; returns the angle 
arccosec (a)  inverse cosecant  a is the cosecant ratio; returns the angle 
arccotan (a)  inverse cotangent  a is the cotangent ratio; returns the angle 
abs (a)  absolute value  returns the absolute value of a 
exp (n)  exponential  returns e raised to the power of n 
log (a)  logarithmic  returns the natural log of a to the base e 
sqr (a)  square root  returns the square root of a 
int (a)  integer  returns a as an integer 
sgn (a)  sign  returns the sign of a as 1 or 1 For example: sgn(21) returns 1 



Constant 


pi  pi  ratio of the circumference to the diameter of a circle (3.14...) 
Hi Jerry and Jason,
Yes that is how a parametric equation is stated. And yes those are the standard functions. My old CAD system, Vectorworks which I still have, allows me to create a 3d surface using parametric equations. I have to write a script to do it but it works pretty good. I used it to create a turbine blade by formula. In the script I can enter commands to "place a point" etc with fields for x, y, z which is where the formula goes. Their commands are openly available. I see no such functionality in Solidworks which I though was a superior system when I bought it. So now I have to create my blades in Vectorworks and export the surface into Solidworks. It is a compund curve so I can't just draw it on a plane and project it.
yes, SW does not currently have an equation driven surface feature.
you can, as Jerry mentions, do an equation driven curve. and you could connect some of these in a loft or boundary surface/solid.
Yes, that does work and yes I was able to create a surface and solid. But when I entered the mirror equations to create the other side someting strange happened. There are two curves, differing only in their radius. One came out correct, the other has the correct start and end points but curves in the opposote direction. I've tried a dozen variations, no luck. Each of the three equations has a coefficient for the radius. That's the only difference between the two equations.
Start a new part.
Click the insert tab, select 3D sketch.
Now left click out in the work field, and select Equation driven curve ...
That's all i've got :)