Continue to Site

Welcome to MCAD Central

Join our MCAD Central community forums, the largest resource for MCAD (Mechanical Computer-Aided Design) professionals, including files, forums, jobs, articles, calendar, and more.

Register Log in

curve wrap on a sphere

Maybe they really wanted wrap which maintains the length of the curve.


You can only wrap on ruled surfaces, a cylinder and planer surfaces are ruled, however a sphere is not a ruled surface.
 
I have one clue for this,


create curve using trajpar withspherical coordinate system, control the length of the curve using analysis feature and a conditional statement. (little related to BMX)


I think this clue can kick start the apraoch and you will do it !!!
 
I want to see BMX in action like that! That stuff is over my head. Maybe Ill try to learn that next? Has anyone taken a BMX class?


Edited by: design-engine
 
I think this simple methodwill beuseful.<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


Instead of trying to wrap or project, you may try creating curve using equation. You can specify centre, radiusof the sphere and number of turns required.


Insert>model datum>curve>from equation>done>(select coordinate system, which is the centre of our sphere)>cylindrical> now you will get notepad to edit relation>Use the following equation:


<B style="mso-bidi-font-weight: normal">r= 3*sin(t*180)
theta=t*360*10
z=3*cos(t*180)[/B]


In this 3: radius


t: varies between 0 to 1


10: no of turns/coils


Here the curve starts at t=0 and corresponding values of r=0, theta=0 and z=3 (sin0=0, cos0=1). As t varies from 0 to 1 r varies between 0 to 1 and 1 to 0, theta takes ten rounds of 0 to 360 and z varies from +1 to -1.


If you want the curve at an offset in z direction, you may add constant value to z equation like z=10+3*cos(t*180) then z value varies between 10-13


(You may use either of the cylindrical, spherical or Cartesian coordinate systems, but the equations change)


Thanks


Rudresh
 
play by varying, the way R and Z vary. rate of increase of R increased and Z decrease , vice versa......... all your crazy wayzzzzzzz


-Rudresh
 
Rudesh,



U have spent a lot of time of studying that i think

That is cool



One more thing



How to make the cylinder into ovel



Hope there will be some way



do you have any similar varieties using equation methord
 
Circle is a case of ellipse, in which rx=ry, therefore r & z vary through similar values in the equation : <?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


r= 3*sin(t*180)
theta=t*360*10
z=3*cos(t*180)<B style="mso-bidi-font-weight: normal">[/B]


here multiply z variable to the extent of the ratio of ry and rx, for example in the following figure, ry which represent z is equal to 4.5 and rx equal to 3. Here change the relation as


r= 3*sin(t*180)
theta=t*360*10
z=4.5*cos(t*180)


the resulting curve will wrap around an oval of rx=3 and ry=4.5


in other words the relation is


r= 3*sin(t*180)
theta=t*360*10
z=3*1.5*cos(t*180)





I think this helps, if I have understanding of oval is correct ;-)
 
sorry All,<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />


I have simple way, you just need to directly include values of rx and ry in the relation as follows:
r= rx*sin(t*180)
theta=t*360*10
z=ry*cos(t*180)

for an ellipse of rx =6 and ry=8
relation will be:
r= 6*sin(t*180)
theta=t*360*10
z=8*cos(t*180)


thnx


Rudresh
 
These are some cool relations suerly it will be of use in upcoming projects



but now i am having a project



IS there a way to do this
 
following equations help


x=4*sin(t*180)*cos(10*t*360)
y=6*sin(t*180)*sin(10*t*360)
z=8*cos(t*180)


where 4,6 and 8 radii in x, y and z directions. See the attached pic showing the dimension of the ellipsoid








thanks


Rudresh
 
You must log in or register to reply here.

Sponsor

Articles From 3DCAD World

Back
Top