Hi everyone,
I'm trying generate a design for 3D-printed objects for a simple mechanism.
For example, imagine a 50mm wheel lying on its side on a flat base. The
wheel rotates about an axle through 180 degrees. On the top side of the
wheel is an object which can also revolve around its own centre (Hopefully
the "Insert image" button will show what I mean). So far, so easy... an
axle at the centre of the wheel, and an axle at the centre of the object.
However, I'd like to constrain the motion, so that as the wheel revolves,
I'd like the object to maintain its <b>orientation relative to the
base</b>, and the <b>position of its centre relative to the wheel</b>.
My thinking is to cut slots in the base... pins in the object would follow
those slots. If the Y distance between the slots is the same as the
distance between the pins, they will maintain that orientation. There would
also need to be semi-circular slots through the wheel for these pins to go
through.
I guess that in this case I'm trying to define objects which are
semicircular rotate_extruded paths, to subtract from the base. But I'd
prefer not to do any maths to figure out the centre and radius of these
semicircles. And (of course), if this is possible, I'd like to be able to
do more complex paths.
Is there some way in OpenSCAD to generate these slots? For example, for the
slots in the base, I'd like to know the path that the pins would follow as
the object rotates around its axis as the wheel rotates around its axis.
Frank
Hi everyone,
I'm trying generate a design for 3D-printed objects for a simple mechanism.
For example, imagine a 50mm wheel lying on its side on a flat base. The
wheel rotates about an axle through 180 degrees. On the top side of the
wheel is an object which can also revolve around its own centre (Hopefully
the "Insert image" button will show what I mean). So far, so easy... an
axle at the centre of the wheel, and an axle at the centre of the object.
However, I'd like to constrain the motion, so that as the wheel revolves,
I'd like the object to maintain its <b>orientation relative to the
base</b>, and the <b>position of its centre relative to the wheel</b>.
My thinking is to cut slots in the base... pins in the object would follow
those slots. If the Y distance between the slots is the same as the
distance between the pins, they will maintain that orientation. There would
also need to be semi-circular slots through the wheel for these pins to go
through.
I guess that in this case I'm trying to define objects which are
semicircular rotate_extruded paths, to subtract from the base. But I'd
prefer not to do any maths to figure out the centre and radius of these
semicircles. And (of course), if this is possible, I'd like to be able to
do more complex paths.
Is there some way in OpenSCAD to generate these slots? For example, for the
slots in the base, I'd like to know the path that the pins would follow as
the object rotates around its axis as the wheel rotates around its axis.
Frank
