These are living hinges: http://www.thingiverse.com/thing:12708 http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ http://www.deferredprocrastination.co.uk/blog/2011/laser-cut-lattice-living-hinges/ Is there an openscad library of these things? Anyone work with them before? I'm thinking of some kind of module where you enter the width and height of the pattern you want, and the thickness of the material, and poof, it outputs a pattern of a living hinge. Just trying to not reinvent the wheel. Thanks, Ari M Diacou

translate ([-1, d / 2, cut])
rotate ([45, 0, 0])
   cube ([w + 2, 2, h]) ;

         - Michele

On 08-23-2016 2:17 PM, Ari Diacou wrote: > These are living hinges: > > http://www.thingiverse.com/thing:12708 > http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ > http://www.deferredprocrastination.co.uk/blog/2011/laser-cut-lattice-living-hinges/ > > Is there an openscad library of these things? Anyone work with them > before? > > I'm thinking of some kind of module where you enter the width and > height of the pattern you want, and the thickness of the material, and > poof, it outputs a pattern of a living hinge. > > Just trying to not reinvent the wheel. Living hinges are pretty cool and very easy to make. I just difference a cube on edge to chisel into into a flat sheet and they come out very nice. Eg.: w = 38 ; d = 26 ; h = 2 ; cut = 1 ; difference () { cube ([w, d, h]) ; translate ([-1, d / 2, cut]) rotate ([45, 0, 0]) cube ([w + 2, 2, h]) ; } Polypropylene works very well for living hinges and is easy to work with. I generally go for a 1 mm. hinge thickness. Smaller will give you more flexible hinges, thicker makes them stronger but they still work. - Michele

So I created it. Could you nerds give me any feedback? Any features you'd want? Any settings that totally mess it up? I'll put it up on Thingiverse, I think under a GNU license, once you give it a quick vetting. Thanks, --Ari M Diacou Metis Industries //Living Hinge //Ari M Diacou //Metis Industries //August 2016 ///////////////////////////////// Main() ////////////////////////////////////// //Uncomment lines to see samples hinge7(); //hinge7(d=6); //hinge7(length=20, width=40,d=6,hinge_length=2.5,hinges_across_length=2,minimum_thinness=3); //hinge7(length=30, width=20,d=2,hinge_length=2.5,hinges_across_length=2,minimum_thinness=3,center=true); //hinge7(length=20, width=40,d=3,hinge_length=4,hinges_across_length=0,minimum_thinness=1); /////////////////////////////// Functions ///////////////////////////////////// module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_length=3,hinges_across_length=2,center=false){ //moves difference(){ square(...) outside of if(m=0) statement, compared to hinge6() //length = the y dimension of the hinge, parallel to the laser cuts //width = the x dimension of the hinge, transverse to laser cuts //d=the distance between parallel laser cuts //What is the minimum distance that two parallel lines can be apart before the laser does something catastrophic? E.g. setting uncontrollable fire to the work piece. This is "minimum_thinness" //hinge_length=the distance between 2 colinear laser cuts //hinges_across_length=the number of hinges across the length of the hinge //center is a boolean value, if true, place the center of the rectangle at the origin, if false, put the bottom left corner at the origin (just like square() and cube()) ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for OpenSCAD 2015.03) used to make square()'s which look like lines (which OpenSCAD doesn't support). Hopefully, your laser has a function which says something like "ignore cuts less than THRESHOLD apart", set that to anything greater than ep. adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the center position th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is less than the minimum thickness, just make linear cuts, specifically, set the width=th=thickness of the squares to ep, which is just above 1 micron (for 1=1mm slicers) n=floor(width/d); m=floor(abs(hinges_across_length)); echo(str("Number of hinges (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} echo(str("The distance between parallel laser cuts (d) is: ",d," mm.")); //the length of the short lines short=(length-m*hinge_length)/(m+1); //the length of the long lines long=(length-(m+1)*hinge_length)/(m); echo(str("There should be n=",n," links in the hinge.")); translate(adjust) difference(){ square([width,length],center=false); if(m==0) //In the special case where |hinges_across_length|<1, the hinge should look like: // | --------------------------------------| // |-------------------------------------- | // | --------------------------------------| // |-------------------------------------- | for(i=[0:n]) translate([i*d,(pow(-1,i))*hinge_length]) // (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} square([th,length]); else //A hinge with hinges_across_length=2 should look like: // |------------ ------------ ------------| // | ----------------- ----------------- | // |------------ ------------ ------------| // | ----------------- ----------------- | for(i=[0:n]){ //Iterating across x translate([i*d*1,0]){ //Do the x translation seperate from the y translations if(i%2==1) //For odd columns for(j=[0:m-1]){ translate([0,hinge_length+j*(long+hinge_length)]) square([th,long]); } if(i%2==0) //For even columns for(j=[0:m]){ translate([0,j*(short+hinge_length)]) square([th,short]); } } } } } On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> wrote: > great links to the maths for torsional and spring calculations. Sounds > like a great idea to work on for openSCAD > > On 8/24/2016 6:17 AM, Ari Diacou wrote: > > These are living hinges: > > http://www.thingiverse.com/thing:12708 > http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ > http://www.deferredprocrastination.co.uk/blog/2011/laser-cut-lattice- > living-hinges/ > > Is there an openscad library of these things? Anyone work with them before? > > I'm thinking of some kind of module where you enter the width and height > of the pattern you want, and the thickness of the material, and poof, it > outputs a pattern of a living hinge. > > Just trying to not reinvent the wheel. > > Thanks, > Ari M Diacou > > > _______________________________________________ > OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > > > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: 08/23/16 > > > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

Nice work, Ari. I did not dig your code enough but I think could be beneficial to have a more general module that, instead of working with a fixed rectangular cutting shape, operates over user defined shapes. Something like: hinge7(params...) my_losangle(); hinge7(params...) rounded_square(); I have no idea how you would control the minimum_thinness though. 2016-08-25 17:18 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: > So I created it. Could you nerds give me any feedback? Any features you'd > want? Any settings that totally mess it up? I'll put it up on Thingiverse, > I think under a GNU license, once you give it a quick vetting. > > Thanks, > --Ari M Diacou > Metis Industries > > //Living Hinge > //Ari M Diacou > //Metis Industries > //August 2016 > > ///////////////////////////////// Main() ////////////////////////////// > //////// > //Uncomment lines to see samples > hinge7(); > //hinge7(d=6); > //hinge7(length=20, width=40,d=6,hinge_length=2.5,hinges_across_length=2, > minimum_thinness=3); > //hinge7(length=30, width=20,d=2,hinge_length=2.5,hinges_across_length=2, > minimum_thinness=3,center=true); > //hinge7(length=20, width=40,d=3,hinge_length=4,hinges_across_length=0, > minimum_thinness=1); > > /////////////////////////////// Functions ////////////////////////////// > /////// > module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_ > length=3,hinges_across_length=2,center=false){ > //moves difference(){ square(...) outside of if(m=0) statement, > compared to hinge6() > //length = the y dimension of the hinge, parallel to the laser cuts > //width = the x dimension of the hinge, transverse to laser cuts > //d=the distance between parallel laser cuts > //What is the minimum distance that two parallel lines can be apart > before the laser does something catastrophic? E.g. setting uncontrollable > fire to the work piece. This is "minimum_thinness" > //hinge_length=the distance between 2 colinear laser cuts > //hinges_across_length=the number of hinges across the length of the > hinge > //center is a boolean value, if true, place the center of the > rectangle at the origin, if false, put the bottom left corner at the origin > (just like square() and cube()) > ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for OpenSCAD > 2015.03) used to make square()'s which look like lines (which OpenSCAD > doesn't support). Hopefully, your laser has a function which says something > like "ignore cuts less than THRESHOLD apart", set that to anything greater > than ep. > adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the > center position > th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is > less than the minimum thickness, just make linear cuts, specifically, set > the width=th=thickness of the squares to ep, which is just above 1 micron > (for 1=1mm slicers) > n=floor(width/d); > m=floor(abs(hinges_across_length)); echo(str("Number of hinges > (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} > echo(str("The distance between parallel laser cuts (d) is: ",d," > mm.")); > //the length of the short lines > short=(length-m*hinge_length)/(m+1); > //the length of the long lines > long=(length-(m+1)*hinge_length)/(m); > echo(str("There should be n=",n," links in the hinge.")); > translate(adjust) difference(){ > square([width,length],center=false); > if(m==0) > //In the special case where |hinges_across_length|<1, the > hinge should look like: > // | --------------------------------------| > // |-------------------------------------- | > // | --------------------------------------| > // |-------------------------------------- | > for(i=[0:n]) > translate([i*d,(pow(-1,i))*hinge_length]) // > (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} > square([th,length]); > else > //A hinge with hinges_across_length=2 should look like: > // |------------ ------------ ------------| > // | ----------------- ----------------- | > // |------------ ------------ ------------| > // | ----------------- ----------------- | > for(i=[0:n]){ //Iterating across x > translate([i*d*1,0]){ //Do the x translation seperate from > the y translations > if(i%2==1) //For odd columns > for(j=[0:m-1]){ > translate([0,hinge_length+j*( > long+hinge_length)]) > square([th,long]); > } > if(i%2==0) //For even columns > for(j=[0:m]){ > translate([0,j*(short+hinge_length)]) > square([th,short]); > } > } > } > } > } > > On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> > wrote: > >> great links to the maths for torsional and spring calculations. Sounds >> like a great idea to work on for openSCAD >> >> On 8/24/2016 6:17 AM, Ari Diacou wrote: >> >> These are living hinges: >> >> http://www.thingiverse.com/thing:12708 >> http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ >> http://www.deferredprocrastination.co.uk/blog/2011/laser- >> cut-lattice-living-hinges/ >> >> Is there an openscad library of these things? Anyone work with them >> before? >> >> I'm thinking of some kind of module where you enter the width and height >> of the pattern you want, and the thickness of the material, and poof, it >> outputs a pattern of a living hinge. >> >> Just trying to not reinvent the wheel. >> >> Thanks, >> Ari M Diacou >> >> >> _______________________________________________ >> OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> >> >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: 08/23/16 >> >> >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

Thanks Ronaldo for the feedback. I can give that a think... I see 2 problems: 1) If I am calling children to make my module modify another module, I dont (think I) have a way to get the dimensional information of the child module, so hinge8() would not know what to set "length" and "width" to use, which are called extensively in the code. 2) When you want a hinge, dont you almost always want it to be rectangular in profile? Under what conditions would you NOT want the profile of the hinge to be rectangular? Are you thinking something like: ? module add_hinge(length,width,...){ union(){ hinge7(length,width,center=true,...); difference(){ children(); square([length,width]); } } } On Thu, Aug 25, 2016 at 5:11 PM, Ronaldo Persiano <rcmpersiano@gmail.com> wrote: > Nice work, Ari. I did not dig your code enough but I think could be > beneficial to have a more general module that, instead of working with a > fixed rectangular cutting shape, operates over user defined shapes. > Something like: > hinge7(params...) my_losangle(); > hinge7(params...) rounded_square(); > I have no idea how you would control the minimum_thinness though. > > 2016-08-25 17:18 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: > >> So I created it. Could you nerds give me any feedback? Any features you'd >> want? Any settings that totally mess it up? I'll put it up on Thingiverse, >> I think under a GNU license, once you give it a quick vetting. >> >> Thanks, >> --Ari M Diacou >> Metis Industries >> >> //Living Hinge >> //Ari M Diacou >> //Metis Industries >> //August 2016 >> >> ///////////////////////////////// Main() ////////////////////////////// >> //////// >> //Uncomment lines to see samples >> hinge7(); >> //hinge7(d=6); >> //hinge7(length=20, width=40,d=6,hinge_length=2.5, >> hinges_across_length=2,minimum_thinness=3); >> //hinge7(length=30, width=20,d=2,hinge_length=2.5, >> hinges_across_length=2,minimum_thinness=3,center=true); >> //hinge7(length=20, width=40,d=3,hinge_length=4,hi >> nges_across_length=0,minimum_thinness=1); >> >> /////////////////////////////// Functions ////////////////////////////// >> /////// >> module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_lengt >> h=3,hinges_across_length=2,center=false){ >> //moves difference(){ square(...) outside of if(m=0) statement, >> compared to hinge6() >> //length = the y dimension of the hinge, parallel to the laser cuts >> //width = the x dimension of the hinge, transverse to laser cuts >> //d=the distance between parallel laser cuts >> //What is the minimum distance that two parallel lines can be apart >> before the laser does something catastrophic? E.g. setting uncontrollable >> fire to the work piece. This is "minimum_thinness" >> //hinge_length=the distance between 2 colinear laser cuts >> //hinges_across_length=the number of hinges across the length of the >> hinge >> //center is a boolean value, if true, place the center of the >> rectangle at the origin, if false, put the bottom left corner at the origin >> (just like square() and cube()) >> ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for >> OpenSCAD 2015.03) used to make square()'s which look like lines (which >> OpenSCAD doesn't support). Hopefully, your laser has a function which says >> something like "ignore cuts less than THRESHOLD apart", set that to >> anything greater than ep. >> adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the >> center position >> th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is >> less than the minimum thickness, just make linear cuts, specifically, set >> the width=th=thickness of the squares to ep, which is just above 1 micron >> (for 1=1mm slicers) >> n=floor(width/d); >> m=floor(abs(hinges_across_length)); echo(str("Number of hinges >> (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} >> echo(str("The distance between parallel laser cuts (d) is: ",d," >> mm.")); >> //the length of the short lines >> short=(length-m*hinge_length)/(m+1); >> //the length of the long lines >> long=(length-(m+1)*hinge_length)/(m); >> echo(str("There should be n=",n," links in the hinge.")); >> translate(adjust) difference(){ >> square([width,length],center=false); >> if(m==0) >> //In the special case where |hinges_across_length|<1, the >> hinge should look like: >> // | --------------------------------------| >> // |-------------------------------------- | >> // | --------------------------------------| >> // |-------------------------------------- | >> for(i=[0:n]) >> translate([i*d,(pow(-1,i))*hinge_length]) // >> (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} >> square([th,length]); >> else >> //A hinge with hinges_across_length=2 should look like: >> // |------------ ------------ ------------| >> // | ----------------- ----------------- | >> // |------------ ------------ ------------| >> // | ----------------- ----------------- | >> for(i=[0:n]){ //Iterating across x >> translate([i*d*1,0]){ //Do the x translation seperate >> from the y translations >> if(i%2==1) //For odd columns >> for(j=[0:m-1]){ >> translate([0,hinge_length+j*(l >> ong+hinge_length)]) >> square([th,long]); >> } >> if(i%2==0) //For even columns >> for(j=[0:m]){ >> translate([0,j*(short+hinge_length)]) >> square([th,short]); >> } >> } >> } >> } >> } >> >> On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> >> wrote: >> >>> great links to the maths for torsional and spring calculations. Sounds >>> like a great idea to work on for openSCAD >>> >>> On 8/24/2016 6:17 AM, Ari Diacou wrote: >>> >>> These are living hinges: >>> >>> http://www.thingiverse.com/thing:12708 >>> http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ >>> http://www.deferredprocrastination.co.uk/blog/2011/laser-cut >>> -lattice-living-hinges/ >>> >>> Is there an openscad library of these things? Anyone work with them >>> before? >>> >>> I'm thinking of some kind of module where you enter the width and height >>> of the pattern you want, and the thickness of the material, and poof, it >>> outputs a pattern of a living hinge. >>> >>> Just trying to not reinvent the wheel. >>> >>> Thanks, >>> Ari M Diacou >>> >>> >>> _______________________________________________ >>> OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >>> >>> >>> No virus found in this message. >>> Checked by AVG - www.avg.com >>> Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: >>> 08/23/16 >>> >>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> Discuss@lists.openscad.org >>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >>> >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

The first problem: your code can assume or expect a* centered* standard footprint for the shape. Let's say 1x1 or 10x10. The hinge module will position and stretch the children shape to meet its parameters. Yes, you may *inside *the hinge module crop the shape to the 1x1 standard if you want to. The second: you feed me with that ideas! The second reference of your first message shows several very beautiful non rectangular cutting paterns. ;) 2016-08-25 18:38 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: > Thanks Ronaldo for the feedback. I can give that a think... > > I see 2 problems: > 1) If I am calling children to make my module modify another module, I > dont (think I) have a way to get the dimensional information of the child > module, so hinge8() would not know what to set "length" and "width" to use, > which are called extensively in the code. > > 2) When you want a hinge, dont you almost always want it to be rectangular > in profile? Under what conditions would you NOT want the profile of the > hinge to be rectangular? > > Are you thinking something like: ? > > module add_hinge(length,width,...){ > union(){ > hinge7(length,width,center=true,...); > difference(){ > children(); > square([length,width]); > } > } > } > > > On Thu, Aug 25, 2016 at 5:11 PM, Ronaldo Persiano <rcmpersiano@gmail.com> > wrote: > >> Nice work, Ari. I did not dig your code enough but I think could be >> beneficial to have a more general module that, instead of working with a >> fixed rectangular cutting shape, operates over user defined shapes. >> Something like: >> hinge7(params...) my_losangle(); >> hinge7(params...) rounded_square(); >> I have no idea how you would control the minimum_thinness though. >> >> 2016-08-25 17:18 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: >> >>> So I created it. Could you nerds give me any feedback? Any features >>> you'd want? Any settings that totally mess it up? I'll put it up on >>> Thingiverse, I think under a GNU license, once you give it a quick vetting. >>> >>> Thanks, >>> --Ari M Diacou >>> Metis Industries >>> >>> //Living Hinge >>> //Ari M Diacou >>> //Metis Industries >>> //August 2016 >>> >>> ///////////////////////////////// Main() ////////////////////////////// >>> //////// >>> //Uncomment lines to see samples >>> hinge7(); >>> //hinge7(d=6); >>> //hinge7(length=20, width=40,d=6,hinge_length=2.5, >>> hinges_across_length=2,minimum_thinness=3); >>> //hinge7(length=30, width=20,d=2,hinge_length=2.5, >>> hinges_across_length=2,minimum_thinness=3,center=true); >>> //hinge7(length=20, width=40,d=3,hinge_length=4,hi >>> nges_across_length=0,minimum_thinness=1); >>> >>> /////////////////////////////// Functions ////////////////////////////// >>> /////// >>> module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_lengt >>> h=3,hinges_across_length=2,center=false){ >>> //moves difference(){ square(...) outside of if(m=0) statement, >>> compared to hinge6() >>> //length = the y dimension of the hinge, parallel to the laser cuts >>> //width = the x dimension of the hinge, transverse to laser cuts >>> //d=the distance between parallel laser cuts >>> //What is the minimum distance that two parallel lines can be apart >>> before the laser does something catastrophic? E.g. setting uncontrollable >>> fire to the work piece. This is "minimum_thinness" >>> //hinge_length=the distance between 2 colinear laser cuts >>> //hinges_across_length=the number of hinges across the length of the >>> hinge >>> //center is a boolean value, if true, place the center of the >>> rectangle at the origin, if false, put the bottom left corner at the origin >>> (just like square() and cube()) >>> ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for >>> OpenSCAD 2015.03) used to make square()'s which look like lines (which >>> OpenSCAD doesn't support). Hopefully, your laser has a function which says >>> something like "ignore cuts less than THRESHOLD apart", set that to >>> anything greater than ep. >>> adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the >>> center position >>> th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is >>> less than the minimum thickness, just make linear cuts, specifically, set >>> the width=th=thickness of the squares to ep, which is just above 1 micron >>> (for 1=1mm slicers) >>> n=floor(width/d); >>> m=floor(abs(hinges_across_length)); echo(str("Number of hinges >>> (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} >>> echo(str("The distance between parallel laser cuts (d) is: ",d," >>> mm.")); >>> //the length of the short lines >>> short=(length-m*hinge_length)/(m+1); >>> //the length of the long lines >>> long=(length-(m+1)*hinge_length)/(m); >>> echo(str("There should be n=",n," links in the hinge.")); >>> translate(adjust) difference(){ >>> square([width,length],center=false); >>> if(m==0) >>> //In the special case where |hinges_across_length|<1, the >>> hinge should look like: >>> // | --------------------------------------| >>> // |-------------------------------------- | >>> // | --------------------------------------| >>> // |-------------------------------------- | >>> for(i=[0:n]) >>> translate([i*d,(pow(-1,i))*hinge_length]) // >>> (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} >>> square([th,length]); >>> else >>> //A hinge with hinges_across_length=2 should look like: >>> // |------------ ------------ ------------| >>> // | ----------------- ----------------- | >>> // |------------ ------------ ------------| >>> // | ----------------- ----------------- | >>> for(i=[0:n]){ //Iterating across x >>> translate([i*d*1,0]){ //Do the x translation seperate >>> from the y translations >>> if(i%2==1) //For odd columns >>> for(j=[0:m-1]){ >>> translate([0,hinge_length+j*(l >>> ong+hinge_length)]) >>> square([th,long]); >>> } >>> if(i%2==0) //For even columns >>> for(j=[0:m]){ >>> translate([0,j*(short+hinge_length)]) >>> square([th,short]); >>> } >>> } >>> } >>> } >>> } >>> >>> On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> >>> wrote: >>> >>>> great links to the maths for torsional and spring calculations. Sounds >>>> like a great idea to work on for openSCAD >>>> >>>> On 8/24/2016 6:17 AM, Ari Diacou wrote: >>>> >>>> These are living hinges: >>>> >>>> http://www.thingiverse.com/thing:12708 >>>> http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ >>>> http://www.deferredprocrastination.co.uk/blog/2011/laser-cut >>>> -lattice-living-hinges/ >>>> >>>> Is there an openscad library of these things? Anyone work with them >>>> before? >>>> >>>> I'm thinking of some kind of module where you enter the width and >>>> height of the pattern you want, and the thickness of the material, and >>>> poof, it outputs a pattern of a living hinge. >>>> >>>> Just trying to not reinvent the wheel. >>>> >>>> Thanks, >>>> Ari M Diacou >>>> >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>> >>>> >>>> >>>> No virus found in this message. >>>> Checked by AVG - www.avg.com >>>> Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: >>>> 08/23/16 >>>> >>>> >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing list >>>> Discuss@lists.openscad.org >>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>> >>>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> Discuss@lists.openscad.org >>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >>> >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

Okay Ronaldo, you got your wish. I think "add_hinge() circle()" works the way you want it to: //Living Hinge //Ari M Diacou //Metis Industries //August 2016 //Thanks to Ronaldo Persiano for the inspiration for add_hinge() ///////////////////////////// Parameters ///////////////////////////////////// // preview[view:north, tilt:top] //The y dimension of the hinge, parallel to the laser cuts length=30; //The x dimension of the hinge, transverse to laser cuts width=40; //The distance between parallel laser cuts d=6; //The distance between 2 collinear laser cuts hinge_length=3; //The number of hinges across the length of the hinge hinges_across_length=1; //How thick do you want the hinge to be height=5; ///////////////////////////////// Main() ////////////////////////////////////// //linear_extrude(height) hinge(length=length,width=width,d=d,minimum_thinness=.01,hinge_length=hinge_length,hinges_across_length=hinges_across_length); ////Uncomment lines to see samples (all flat for DXF exporting) //hinge(); //hinge(d=6); //hinge(length=20, width=39,d=6,hinge_length=2.5,hinges_across_length=2,minimum_thinness=3); //hinge(length=30, width=20,d=2,hinge_length=2.5,hinges_across_length=2,minimum_thinness=3,center=true); //hinge(length=20, width=40,d=3,hinge_length=4,hinges_across_length=0,minimum_thinness=1); //linear_extrude(height=5) hinge(length=20, width=40,d=6,hinge_length=2.5,hinges_across_length=2,minimum_thinness=3); //add_hinge(width=20,length=length,center=true) square([3*length,length-1],center=true); //add_hinge(width=20,length=90) translate([5,0]) circle(d=90); //add_hinge(width=30,length=90,hinges_across_length=3) circle(d=90); //add_hinge(width=30,length=90,hinges_across_length=3,center=false) circle(d=90); add_hinge(width=30,length=90,hinges_across_length=3,minimum_thinness=.1) circle(d=90); /////////////////////////////// Functions ///////////////////////////////////// module hinge(length=30,width=20,d=3,minimum_thinness=3,hinge_length=3,hinges_across_length=2,center=false){ //length = the y dimension of the hinge, parallel to the laser cuts //width = the x dimension of the hinge, transverse to laser cuts //d=the distance between parallel laser cuts //What is the minimum distance that two parallel lines can be apart before the laser does something catastrophic? E.g. setting uncontrollable fire to the work piece. This is "minimum_thinness" //hinge_length=the distance between 2 collinear laser cuts //hinges_across_length=the number of hinges across the length of the hinge //center is a boolean value, if true, place the center of the rectangle at the origin, if false, put the bottom left corner at the origin (just like square() and cube()) ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for OpenSCAD 2015.03) used to make square()'s which look like lines (which OpenSCAD doesn't support). Hopefully, your laser has a function which says something like "ignore cuts less than THRESHOLD apart", set that to anything greater than ep. adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the center position th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is less than the minimum thickness, just make linear cuts, specifically, set the width=th=thickness of the squares to ep, which is just above 1 micron (for 1=1mm slicers) n=floor(width/d); m=floor(abs(hinges_across_length)); echo(str("Number of hinges (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} echo(str("Suggested filename: Living Hinge-",length,"x",width,"mm-h=",m,"x",hinge_length,"-th=",th)); echo(str("The distance between parallel laser cuts (d) is: ",d," mm.")); //the length of the short lines short=(length-m*hinge_length)/(m+1); //the length of the long lines long=(length-(m+1)*hinge_length)/(m); echo(str("There should be n=",n," links in the hinge.")); translate(adjust) difference(){ square([width,length],center=false); if(m==0) //In the special case where |hinges_across_length|<1, the hinge should look like: // | --------------------------------------| // |-------------------------------------- | // | --------------------------------------| // |-------------------------------------- | for(i=[0:n]) translate([i*d,(pow(-1,i))*hinge_length]) // (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} square([th,length]); else //A hinge with hinges_across_length=2 should look like: // |------------ ------------ ------------| // | ----------------- ----------------- | // |------------ ------------ ------------| // | ----------------- ----------------- | for(i=[0:n]){ //Iterating across x translate([i*d*1,0]){ //Do the x translation separate from the y translations if(i%2==1) //For odd columns for(j=[0:m-1]){ translate([0,hinge_length+j*(long+hinge_length)]) square([th,long]); } if(i%2==0) //For even columns for(j=[0:m]){ translate([0,j*(short+hinge_length)]) square([th,short]); } } } } } module add_hinge(length=30,width=20,d=3,minimum_thinness=3,hinge_length=3,hinges_across_length=2,center=true){ //add_hinge() modifies another 2D object, by adding a hinge which is centered on the origin (by default, this can be changed to false, so that the bottom left corner of the hinge is at the origin. It uses the same parameters as hinge(). //First, difference() a rectangle the size of the hinge from the child object (makes a hole for the hinge //Second, union() a hinge with First (puts the hinge in the hole) //Third, intersection() the child object with Second (cuts off any extra hinge that sticks out past the child object) intersection(){ children(); union(){ hinge(length=length,width=width,d=d,minimum_thinness=minimum_thinness,hinge_length=hinge_length,hinges_across_length=hinges_across_length,center=center); difference(){ children(); square([width,length],center=center); } } } } On Thu, Aug 25, 2016 at 6:21 PM, Ronaldo Persiano <rcmpersiano@gmail.com> wrote: > The first problem: your code can assume or expect a* centered* standard > footprint for the shape. Let's say 1x1 or 10x10. The hinge module will > position and stretch the children shape to meet its parameters. Yes, you > may *inside *the hinge module crop the shape to the 1x1 standard if you > want to. > > The second: you feed me with that ideas! The second reference of your > first message shows several very beautiful non rectangular cutting paterns. > ;) > > 2016-08-25 18:38 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: > >> Thanks Ronaldo for the feedback. I can give that a think... >> >> I see 2 problems: >> 1) If I am calling children to make my module modify another module, I >> dont (think I) have a way to get the dimensional information of the child >> module, so hinge8() would not know what to set "length" and "width" to use, >> which are called extensively in the code. >> >> 2) When you want a hinge, dont you almost always want it to be >> rectangular in profile? Under what conditions would you NOT want the >> profile of the hinge to be rectangular? >> >> Are you thinking something like: ? >> >> module add_hinge(length,width,...){ >> union(){ >> hinge7(length,width,center=true,...); >> difference(){ >> children(); >> square([length,width]); >> } >> } >> } >> >> >> On Thu, Aug 25, 2016 at 5:11 PM, Ronaldo Persiano <rcmpersiano@gmail.com> >> wrote: >> >>> Nice work, Ari. I did not dig your code enough but I think could be >>> beneficial to have a more general module that, instead of working with a >>> fixed rectangular cutting shape, operates over user defined shapes. >>> Something like: >>> hinge7(params...) my_losangle(); >>> hinge7(params...) rounded_square(); >>> I have no idea how you would control the minimum_thinness though. >>> >>> 2016-08-25 17:18 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: >>> >>>> So I created it. Could you nerds give me any feedback? Any features >>>> you'd want? Any settings that totally mess it up? I'll put it up on >>>> Thingiverse, I think under a GNU license, once you give it a quick vetting. >>>> >>>> Thanks, >>>> --Ari M Diacou >>>> Metis Industries >>>> >>>> //Living Hinge >>>> //Ari M Diacou >>>> //Metis Industries >>>> //August 2016 >>>> >>>> ///////////////////////////////// Main() ////////////////////////////// >>>> //////// >>>> //Uncomment lines to see samples >>>> hinge7(); >>>> //hinge7(d=6); >>>> //hinge7(length=20, width=40,d=6,hinge_length=2.5, >>>> hinges_across_length=2,minimum_thinness=3); >>>> //hinge7(length=30, width=20,d=2,hinge_length=2.5, >>>> hinges_across_length=2,minimum_thinness=3,center=true); >>>> //hinge7(length=20, width=40,d=3,hinge_length=4,hi >>>> nges_across_length=0,minimum_thinness=1); >>>> >>>> /////////////////////////////// Functions >>>> ///////////////////////////////////// >>>> module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_lengt >>>> h=3,hinges_across_length=2,center=false){ >>>> //moves difference(){ square(...) outside of if(m=0) statement, >>>> compared to hinge6() >>>> //length = the y dimension of the hinge, parallel to the laser cuts >>>> //width = the x dimension of the hinge, transverse to laser cuts >>>> //d=the distance between parallel laser cuts >>>> //What is the minimum distance that two parallel lines can be apart >>>> before the laser does something catastrophic? E.g. setting uncontrollable >>>> fire to the work piece. This is "minimum_thinness" >>>> //hinge_length=the distance between 2 colinear laser cuts >>>> //hinges_across_length=the number of hinges across the length of >>>> the hinge >>>> //center is a boolean value, if true, place the center of the >>>> rectangle at the origin, if false, put the bottom left corner at the origin >>>> (just like square() and cube()) >>>> ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for >>>> OpenSCAD 2015.03) used to make square()'s which look like lines (which >>>> OpenSCAD doesn't support). Hopefully, your laser has a function which says >>>> something like "ignore cuts less than THRESHOLD apart", set that to >>>> anything greater than ep. >>>> adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the >>>> center position >>>> th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is >>>> less than the minimum thickness, just make linear cuts, specifically, set >>>> the width=th=thickness of the squares to ep, which is just above 1 micron >>>> (for 1=1mm slicers) >>>> n=floor(width/d); >>>> m=floor(abs(hinges_across_length)); echo(str("Number of hinges >>>> (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} >>>> echo(str("The distance between parallel laser cuts (d) is: ",d," >>>> mm.")); >>>> //the length of the short lines >>>> short=(length-m*hinge_length)/(m+1); >>>> //the length of the long lines >>>> long=(length-(m+1)*hinge_length)/(m); >>>> echo(str("There should be n=",n," links in the hinge.")); >>>> translate(adjust) difference(){ >>>> square([width,length],center=false); >>>> if(m==0) >>>> //In the special case where |hinges_across_length|<1, the >>>> hinge should look like: >>>> // | --------------------------------------| >>>> // |-------------------------------------- | >>>> // | --------------------------------------| >>>> // |-------------------------------------- | >>>> for(i=[0:n]) >>>> translate([i*d,(pow(-1,i))*hinge_length]) // >>>> (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} >>>> square([th,length]); >>>> else >>>> //A hinge with hinges_across_length=2 should look like: >>>> // |------------ ------------ ------------| >>>> // | ----------------- ----------------- | >>>> // |------------ ------------ ------------| >>>> // | ----------------- ----------------- | >>>> for(i=[0:n]){ //Iterating across x >>>> translate([i*d*1,0]){ //Do the x translation seperate >>>> from the y translations >>>> if(i%2==1) //For odd columns >>>> for(j=[0:m-1]){ >>>> translate([0,hinge_length+j*(l >>>> ong+hinge_length)]) >>>> square([th,long]); >>>> } >>>> if(i%2==0) //For even columns >>>> for(j=[0:m]){ >>>> translate([0,j*(short+hinge_length)]) >>>> square([th,short]); >>>> } >>>> } >>>> } >>>> } >>>> } >>>> >>>> On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> >>>> wrote: >>>> >>>>> great links to the maths for torsional and spring calculations. Sounds >>>>> like a great idea to work on for openSCAD >>>>> >>>>> On 8/24/2016 6:17 AM, Ari Diacou wrote: >>>>> >>>>> These are living hinges: >>>>> >>>>> http://www.thingiverse.com/thing:12708 >>>>> http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ >>>>> http://www.deferredprocrastination.co.uk/blog/2011/laser-cut >>>>> -lattice-living-hinges/ >>>>> >>>>> Is there an openscad library of these things? Anyone work with them >>>>> before? >>>>> >>>>> I'm thinking of some kind of module where you enter the width and >>>>> height of the pattern you want, and the thickness of the material, and >>>>> poof, it outputs a pattern of a living hinge. >>>>> >>>>> Just trying to not reinvent the wheel. >>>>> >>>>> Thanks, >>>>> Ari M Diacou >>>>> >>>>> >>>>> _______________________________________________ >>>>> OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>>> >>>>> >>>>> >>>>> No virus found in this message. >>>>> Checked by AVG - www.avg.com >>>>> Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: >>>>> 08/23/16 >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> OpenSCAD mailing list >>>>> Discuss@lists.openscad.org >>>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing list >>>> Discuss@lists.openscad.org >>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>> >>>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> Discuss@lists.openscad.org >>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >>> >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

I think I have not made myself clear. I had called shape the hinge repeated cutting shape. Your add_hinge has its own use but what I meant was: ​ ​that I got with the following ad hoc code: module shape1(b,a) { square([b/8,a], center=true); translate([-b+b/16,a-a/2]) square([b,a/4]); translate([-b/16,-a+a/4]) square([b,a/4]); } module shape2(s) { square([s,s/2],center=true); square([s/2,s],center=true); } module shape3(a,b) { scale([a,b]) rotate(45) square(); } module hinge(s1,s2,offset=true){ difference(){ square([200,170]); translate([0,50]) for(i=[0:10], j=[0:5]) { if ( (j%2) && offset ) { translate([s1*(i+0.5),s2*j]) children(); } else { translate([s1*i,s2*j]) children(); } } } } hinge(s1=26,s2=15,offset=false) shape1(20,6); translate([220,0]) hinge(s1=21,s2=16) shape2(17); translate([440,0]) hinge(s1=100,s2=12) shape3(60,12); Note that I added one more parameter to allow patterns with no offset between rows. As I said before, I don't know how you could deal with the " minimum_thinness" in this case. 2016-08-26 11:23 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: > Okay Ronaldo, you got your wish. I think "add_hinge() circle()" works the > way you want it to: > > //Living Hinge > //Ari M Diacou > //Metis Industries > //August 2016 > > //Thanks to Ronaldo Persiano for the inspiration for add_hinge() > > ///////////////////////////// Parameters ////////////////////////////// > /////// > // preview[view:north, tilt:top] > //The y dimension of the hinge, parallel to the laser cuts > length=30; > //The x dimension of the hinge, transverse to laser cuts > width=40; > //The distance between parallel laser cuts > d=6; > //The distance between 2 collinear laser cuts > hinge_length=3; > //The number of hinges across the length of the hinge > hinges_across_length=1; > //How thick do you want the hinge to be > height=5; > ///////////////////////////////// Main() ////////////////////////////// > //////// > //linear_extrude(height) hinge(length=length,width= > width,d=d,minimum_thinness=.01,hinge_length=hinge_length, > hinges_across_length=hinges_across_length); > ////Uncomment lines to see samples (all flat for DXF exporting) > //hinge(); > //hinge(d=6); > //hinge(length=20, width=39,d=6,hinge_length=2.5,hinges_across_length=2, > minimum_thinness=3); > //hinge(length=30, width=20,d=2,hinge_length=2.5,hinges_across_length=2, > minimum_thinness=3,center=true); > //hinge(length=20, width=40,d=3,hinge_length=4,hinges_across_length=0, > minimum_thinness=1); > //linear_extrude(height=5) hinge(length=20, width=40,d=6,hinge_length=2.5, > hinges_across_length=2,minimum_thinness=3); > //add_hinge(width=20,length=length,center=true) > square([3*length,length-1],center=true); > //add_hinge(width=20,length=90) translate([5,0]) circle(d=90); > //add_hinge(width=30,length=90,hinges_across_length=3) circle(d=90); > //add_hinge(width=30,length=90,hinges_across_length=3,center=false) > circle(d=90); > add_hinge(width=30,length=90,hinges_across_length=3,minimum_thinness=.1) > circle(d=90); > > /////////////////////////////// Functions ////////////////////////////// > /////// > module hinge(length=30,width=20,d=3,minimum_thinness=3,hinge_ > length=3,hinges_across_length=2,center=false){ > //length = the y dimension of the hinge, parallel to the laser cuts > //width = the x dimension of the hinge, transverse to laser cuts > //d=the distance between parallel laser cuts > //What is the minimum distance that two parallel lines can be apart > before the laser does something catastrophic? E.g. setting uncontrollable > fire to the work piece. This is "minimum_thinness" > //hinge_length=the distance between 2 collinear laser cuts > //hinges_across_length=the number of hinges across the length of the > hinge > //center is a boolean value, if true, place the center of the > rectangle at the origin, if false, put the bottom left corner at the origin > (just like square() and cube()) > ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for OpenSCAD > 2015.03) used to make square()'s which look like lines (which OpenSCAD > doesn't support). Hopefully, your laser has a function which says something > like "ignore cuts less than THRESHOLD apart", set that to anything greater > than ep. > adjust=center?-[width,length]/2:[0,0];//a vector for adjusting the > center position > th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is > less than the minimum thickness, just make linear cuts, specifically, set > the width=th=thickness of the squares to ep, which is just above 1 micron > (for 1=1mm slicers) > n=floor(width/d); > m=floor(abs(hinges_across_length)); echo(str("Number of hinges > (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} > echo(str("Suggested filename: Living Hinge-",length,"x",width,"mm- > h=",m,"x",hinge_length,"-th=",th)); > echo(str("The distance between parallel laser cuts (d) is: ",d," > mm.")); > //the length of the short lines > short=(length-m*hinge_length)/(m+1); > //the length of the long lines > long=(length-(m+1)*hinge_length)/(m); > echo(str("There should be n=",n," links in the hinge.")); > translate(adjust) difference(){ > square([width,length],center=false); > if(m==0) > //In the special case where |hinges_across_length|<1, the > hinge should look like: > // | --------------------------------------| > // |-------------------------------------- | > // | --------------------------------------| > // |-------------------------------------- | > for(i=[0:n]) > translate([i*d,(pow(-1,i))*hinge_length]) // > (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} > square([th,length]); > else > //A hinge with hinges_across_length=2 should look like: > // |------------ ------------ ------------| > // | ----------------- ----------------- | > // |------------ ------------ ------------| > // | ----------------- ----------------- | > for(i=[0:n]){ //Iterating across x > translate([i*d*1,0]){ //Do the x translation separate from > the y translations > if(i%2==1) //For odd columns > for(j=[0:m-1]){ > translate([0,hinge_length+j*( > long+hinge_length)]) > square([th,long]); > } > if(i%2==0) //For even columns > for(j=[0:m]){ > translate([0,j*(short+hinge_length)]) > square([th,short]); > } > } > } > } > } > > module add_hinge(length=30,width=20,d=3,minimum_thinness=3,hinge_ > length=3,hinges_across_length=2,center=true){ > //add_hinge() modifies another 2D object, by adding a hinge which is > centered on the origin (by default, this can be changed to false, so that > the bottom left corner of the hinge is at the origin. It uses the same > parameters as hinge(). > //First, difference() a rectangle the size of the hinge from the child > object (makes a hole for the hinge > //Second, union() a hinge with First (puts the hinge in the hole) > //Third, intersection() the child object with Second (cuts off any > extra hinge that sticks out past the child object) > intersection(){ > children(); > union(){ > hinge(length=length,width=width,d=d,minimum_thinness= > minimum_thinness,hinge_length=hinge_length,hinges_across_ > length=hinges_across_length,center=center); > difference(){ > children(); > square([width,length],center=center); > } > } > } > } > > > > On Thu, Aug 25, 2016 at 6:21 PM, Ronaldo Persiano <rcmpersiano@gmail.com> > wrote: > >> The first problem: your code can assume or expect a* centered* standard >> footprint for the shape. Let's say 1x1 or 10x10. The hinge module will >> position and stretch the children shape to meet its parameters. Yes, you >> may *inside *the hinge module crop the shape to the 1x1 standard if you >> want to. >> >> The second: you feed me with that ideas! The second reference of your >> first message shows several very beautiful non rectangular cutting paterns. >> ;) >> >> 2016-08-25 18:38 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: >> >>> Thanks Ronaldo for the feedback. I can give that a think... >>> >>> I see 2 problems: >>> 1) If I am calling children to make my module modify another module, I >>> dont (think I) have a way to get the dimensional information of the child >>> module, so hinge8() would not know what to set "length" and "width" to use, >>> which are called extensively in the code. >>> >>> 2) When you want a hinge, dont you almost always want it to be >>> rectangular in profile? Under what conditions would you NOT want the >>> profile of the hinge to be rectangular? >>> >>> Are you thinking something like: ? >>> >>> module add_hinge(length,width,...){ >>> union(){ >>> hinge7(length,width,center=true,...); >>> difference(){ >>> children(); >>> square([length,width]); >>> } >>> } >>> } >>> >>> >>> On Thu, Aug 25, 2016 at 5:11 PM, Ronaldo Persiano <rcmpersiano@gmail.com >>> > wrote: >>> >>>> Nice work, Ari. I did not dig your code enough but I think could be >>>> beneficial to have a more general module that, instead of working with a >>>> fixed rectangular cutting shape, operates over user defined shapes. >>>> Something like: >>>> hinge7(params...) my_losangle(); >>>> hinge7(params...) rounded_square(); >>>> I have no idea how you would control the minimum_thinness though. >>>> >>>> 2016-08-25 17:18 GMT-03:00 Ari Diacou <ari.diacou@gmail.com>: >>>> >>>>> So I created it. Could you nerds give me any feedback? Any features >>>>> you'd want? Any settings that totally mess it up? I'll put it up on >>>>> Thingiverse, I think under a GNU license, once you give it a quick vetting. >>>>> >>>>> Thanks, >>>>> --Ari M Diacou >>>>> Metis Industries >>>>> >>>>> //Living Hinge >>>>> //Ari M Diacou >>>>> //Metis Industries >>>>> //August 2016 >>>>> >>>>> ///////////////////////////////// Main() >>>>> ////////////////////////////////////// >>>>> //Uncomment lines to see samples >>>>> hinge7(); >>>>> //hinge7(d=6); >>>>> //hinge7(length=20, width=40,d=6,hinge_length=2.5, >>>>> hinges_across_length=2,minimum_thinness=3); >>>>> //hinge7(length=30, width=20,d=2,hinge_length=2.5, >>>>> hinges_across_length=2,minimum_thinness=3,center=true); >>>>> //hinge7(length=20, width=40,d=3,hinge_length=4,hi >>>>> nges_across_length=0,minimum_thinness=1); >>>>> >>>>> /////////////////////////////// Functions >>>>> ///////////////////////////////////// >>>>> module hinge7(length=30,width=20,d=3,minimum_thinness=3,hinge_lengt >>>>> h=3,hinges_across_length=2,center=false){ >>>>> //moves difference(){ square(...) outside of if(m=0) statement, >>>>> compared to hinge6() >>>>> //length = the y dimension of the hinge, parallel to the laser cuts >>>>> //width = the x dimension of the hinge, transverse to laser cuts >>>>> //d=the distance between parallel laser cuts >>>>> //What is the minimum distance that two parallel lines can be >>>>> apart before the laser does something catastrophic? E.g. setting >>>>> uncontrollable fire to the work piece. This is "minimum_thinness" >>>>> //hinge_length=the distance between 2 colinear laser cuts >>>>> //hinges_across_length=the number of hinges across the length of >>>>> the hinge >>>>> //center is a boolean value, if true, place the center of the >>>>> rectangle at the origin, if false, put the bottom left corner at the origin >>>>> (just like square() and cube()) >>>>> ep=.00101;//epsilon, a small number,=1.01 micron, a hack (for >>>>> OpenSCAD 2015.03) used to make square()'s which look like lines (which >>>>> OpenSCAD doesn't support). Hopefully, your laser has a function which says >>>>> something like "ignore cuts less than THRESHOLD apart", set that to >>>>> anything greater than ep. >>>>> adjust=center?-[width,length]/2:[0,0];//a vector for adjusting >>>>> the center position >>>>> th=d/2<minimum_thinness?ep:d/2;//If the distance between lines is >>>>> less than the minimum thickness, just make linear cuts, specifically, set >>>>> the width=th=thickness of the squares to ep, which is just above 1 micron >>>>> (for 1=1mm slicers) >>>>> n=floor(width/d); >>>>> m=floor(abs(hinges_across_length)); echo(str("Number of hinges >>>>> (m)=",m)); //input cleaning, ensures m ϵ {non-negative integers} >>>>> echo(str("The distance between parallel laser cuts (d) is: ",d," >>>>> mm.")); >>>>> //the length of the short lines >>>>> short=(length-m*hinge_length)/(m+1); >>>>> //the length of the long lines >>>>> long=(length-(m+1)*hinge_length)/(m); >>>>> echo(str("There should be n=",n," links in the hinge.")); >>>>> translate(adjust) difference(){ >>>>> square([width,length],center=false); >>>>> if(m==0) >>>>> //In the special case where |hinges_across_length|<1, the >>>>> hinge should look like: >>>>> // | --------------------------------------| >>>>> // |-------------------------------------- | >>>>> // | --------------------------------------| >>>>> // |-------------------------------------- | >>>>> for(i=[0:n]) >>>>> translate([i*d,(pow(-1,i))*hinge_length]) // >>>>> (-1)^i,{iϵZ} = {-1,+1,-1,+1,...} >>>>> square([th,length]); >>>>> else >>>>> //A hinge with hinges_across_length=2 should look like: >>>>> // |------------ ------------ ------------| >>>>> // | ----------------- ----------------- | >>>>> // |------------ ------------ ------------| >>>>> // | ----------------- ----------------- | >>>>> for(i=[0:n]){ //Iterating across x >>>>> translate([i*d*1,0]){ //Do the x translation seperate >>>>> from the y translations >>>>> if(i%2==1) //For odd columns >>>>> for(j=[0:m-1]){ >>>>> translate([0,hinge_length+j*(l >>>>> ong+hinge_length)]) >>>>> square([th,long]); >>>>> } >>>>> if(i%2==0) //For even columns >>>>> for(j=[0:m]){ >>>>> translate([0,j*(short+hinge_length)]) >>>>> square([th,short]); >>>>> } >>>>> } >>>>> } >>>>> } >>>>> } >>>>> >>>>> On Tue, Aug 23, 2016 at 6:26 PM, Mark Schafer <mschafer@wireframe.biz> >>>>> wrote: >>>>> >>>>>> great links to the maths for torsional and spring calculations. >>>>>> Sounds like a great idea to work on for openSCAD >>>>>> >>>>>> On 8/24/2016 6:17 AM, Ari Diacou wrote: >>>>>> >>>>>> These are living hinges: >>>>>> >>>>>> http://www.thingiverse.com/thing:12708 >>>>>> http://blog.ponoko.com/2015/07/06/how-to-design-a-living-hinge/ >>>>>> http://www.deferredprocrastination.co.uk/blog/2011/laser-cut >>>>>> -lattice-living-hinges/ >>>>>> >>>>>> Is there an openscad library of these things? Anyone work with them >>>>>> before? >>>>>> >>>>>> I'm thinking of some kind of module where you enter the width and >>>>>> height of the pattern you want, and the thickness of the material, and >>>>>> poof, it outputs a pattern of a living hinge. >>>>>> >>>>>> Just trying to not reinvent the wheel. >>>>>> >>>>>> Thanks, >>>>>> Ari M Diacou >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> OpenSCAD mailing listDiscuss@lists.openscad.orghttp://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>>>> >>>>>> >>>>>> >>>>>> No virus found in this message. >>>>>> Checked by AVG - www.avg.com >>>>>> Version: 2016.0.7752 / Virus Database: 4647/12863 - Release Date: >>>>>> 08/23/16 >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> OpenSCAD mailing list >>>>>> Discuss@lists.openscad.org >>>>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>>>> >>>>>> >>>>> >>>>> _______________________________________________ >>>>> OpenSCAD mailing list >>>>> Discuss@lists.openscad.org >>>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> OpenSCAD mailing list >>>> Discuss@lists.openscad.org >>>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>>> >>>> >>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> Discuss@lists.openscad.org >>> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >>> >>> >> >> _______________________________________________ >> OpenSCAD mailing list >> Discuss@lists.openscad.org >> http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >> >> > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > >

One more comment: I don't think it is a good idea to crop the shape to constrain it to a rectangle [length, width]. The bounding boxes of shape1 of my code overlaps each other along a row.