Creating knots from equations

[Skiddy]

I am trying to create mathematical knots from equations in pro engineer.

Im creating them through, datum curves and points all created from equations. i realise i can create x,y,z points in cartesian coordinates but i have found no data to represent a knot yet.

I have found a site which sources the creation of most knots off the equation: (Which i presume would be a datum curve)

x=r*cos(phi)*cos(theta)
y=r*cos(phi)*sin(theta)
z=r*sin(phi)

but i cant seem to apply the above equation into pro engineer?

Any ideas?

 

[dgallup]

Your equation appears to be the conversion from spherical coordinates (rho, theta, phi) to cartiesian coordinates (x,y,z), not the equation of a curve or a knot. You have to write your equations in terms of a single independant variable "t" which Pro/E varies from 0 to 1.

To make a datum curve from an equation, first make a part with a default coordinate system. Pro/E will always show it as a cartesian XYZ coordinate system but you can use it as any kind in your datum curve. Next make a datum curve, pick "from equation", pick the coordinate system and then Pro/E will prompt you for what kind of coordinate system you want to use. It will open a text editor with one of the following sets of comments and you have to write the equations for the 3 coordinates in terms of t.

/* For cartesian coordinate system, enter parametric equation
/* in terms of t (which will vary from 0 to 1) for x, y and z
/* For example: for a circle in x-y plane, centered at origin
/* and radius = 4, the parametric equations will be:
/* x = 4 * cos ( t * 360 )
/* y = 4 * sin ( t * 360 )
/* z = 0
/*---------------------------------------------------------

/* For cylindrical coordinate system, enter parametric equation
/* in terms of t (which will vary from 0 to 1) for r, theta and z
/* For example: for a circle in x-y plane, centered at origin
/* and radius = 4, the parametric equations will be:
/* r = 4
/* theta = t * 360
/* z = 0
/*---------------------------------------------------------

/* For spherical coordinate system, enter parametric equation
/* in terms of t (which will vary from 0 to 1) for rho, theta and phi
/* For example: for a circle in x-y plane, centered at origin
/* and radius = 4, the parametric equations will be:
/* rho = 4
/* theta = t * 360
/* phi = 0
/*-------------------------------------------------