Learn FreeCAD Curves Workbench 16: Boat / Ship building with Interpolate Curves Possible solution?

hi viewers and welcome to the channel and welcome to another episode of the mini series for learning the curse workbench for freecad today we're going to be looking at the interpolation curve and how we can utilize that for such things as parametric golden surfaces lofts and surface skeletons for making such things as this boat hole here so this bolt hole has a number of surfaces attached to it so we've got a mirrored golden surface on this one we can use lofts if we so desire and we've got a number of interpolation curves that run across this creating a network of curves to create that surface they're fully parametric and they're attached to these sketches in here so you can see these points have a curve that runs down them both along the horizontal and the vertical and these attach to each of the points of these lines of the sketch and we can adjust the size of these lines pulling in these curves and adjusting our whole width and dimension and shape to create the desired effect that we want we can even place these into a spreadsheet if we so desire so we can control the size of these arms to control each of these planks going through the ship hole obviously this interpolation curve can be used in other applications as well and we'll be exploring one other application for that so i hope you're enjoying the series and let's have a look at this tool if you like this video please hit like and also subscribe to the channel i also have a kofi site where you can actually donate to my contributions to the community and that's at ko hyphen fi.com mang0 so we're in freecad we've started a new document and we're going to come over to the curves workbench and have a look at the tools that we're going to be using we're going to be using the interpolate set of points and we're also going to be using the approximate points to nerves curves or surface we're interested in the nurbs curves not the surface here first of all i'm going to show you how these tools differ these two here interplay certain points and the approximate points we can see that by just doing a simple sketch and using a polyline so create a simple sketch come over to the polyline and i'm going to create a jagged line like so hit escape hit escape again to get the mouse pointer back and close out and come over to the curse workbench now and we've got this jagged line that's made up of a number of points or a number of vertices going through here and the edges that connect up those vertices so i click on the sketch it highlights every single edge in there and if i use the interpolate set points you can see what's happened those points have been interpolated through via a curve that's in there and if i just press spacebar on the sketch you can see how those have been interpolated through there that curve there is a number of options so we got this option here which sets the curve to close so that's true and that will create a closed curve there now if we place this in the part workbench and extruded we can extrude that curve we can also extrude it if we've got this unclosed as well so if it's an open sketch that will actually strut absolutely fine we have polygonal and that set that's true that will actually follow that sketch exactly with one single curve or one single line going through this back to force we also got tolerance here so i bring the sketch back come over to the curve we can set the tolerance we have other parameters here which affects how that curve actually joins up with those dots all those points there we've got uniform we've got custom called length etc and that changes that curve through there the way this differs from an approximate curve i'm going to do exactly the same with approximate curve this one here straight away you can see some difference there so this is our interpolation which follows those points exactly and this one is the approximation so it's not going to fit exactly for instance if you have a golden surface and you approximate the points on that where those two curves cross there may be a gap so they won't be tangent to each other they won't be touching each other and interpolation they will be touching each other also one thing to note is that we can change the algorithm of our approximation curve here so we change that you can see how they deviate differently from each other the interpolation curve and the approximation curve and that's just by changing that algorithm in there approximation so has some continuity in here so we can change that try not to break the curve so there's c1 continuity g1 which breaks c2 so you can see how that continuity affects that curve so we've got two options there all with different parameters that we can choose to create a curve through those points but the question is how can we use this some of these curves can be grouped together and created as a surface going across them allowing us to change the continuity of that surface by the approximate curve or the interpolation curve so i've loaded up a model that i'm working on and i'm just roughing out a very low polygon f1 car so very simple using drafts and chamfers in there just to get the initial shape that i can work with so i've been done by high i'm just trying to create a simple body that i can change into more appealing surface at the moment i've got so far so we can use the interpolation curve to actually pull out curves from this object to create a surface if i select some of these vertices in here so we come in and select these vertices you can increase the size of the points of the models to make this a lot easier then we can use the tool and create a curve through those and then again we could do the same down here so now we've got these curves that are running across here press the spacebar you can see we've got these curves here if we create a number of them then they could be used in a loft so for instance if i bought back my f1 car and carried on say place a curve over the top here and also create some curves across here i can then use these in a loft i can even use them in a ruled surface and we can build up our model from basic polygon shape to more peeling surfaces in there another option will be to look at something like this now this is a boat hole that i'm putting together as an idea that i have that we could use to actually create a golden surface or a loft surface across interpolation curves across there this is made up of groups you can see these groups here and each of these are sections of this hole so if i come into one you can see we've got this sketch here and what i'm going to do is just close out of here and just hide some of these out of the way so we've got this one here this is the smallest one of the lot so this is the front one and you can see i'm working on the half breadth so half of the actual hole itself half the boat and we've got these three lines here which denote the planks that go across the actual hull and not these aren't planks themselves they're just the points of where they connect and you can see these are in tangent with this circle here so these are in radius then we have a number of lines that connect up here so these are construction geometry and we've got a number of lines that connect up to this line here so this one is i believe it's called dead rise in boat building so you have a number of lines here that go straight up so each of the planks connect to these points we can put some constraints in here and also can put constraints for each of the planks that go along here are we going this way so if i bring this around you can see how this is pushing the position this way don't worry about this this is one of the other sections we could put constraints on this radius we could put constraints on on the dead rise if we so desire and we could put constraint on the rise from the water line which will be sitting here to the bottom of the boat if i come out close out here and bring back these groups you can see how these groups are positioned along here if we look at one the groups for instance let's look at this one here and i'm just gonna hide the world surface which is the bottom of the boat so this is a flat bottom boat we could bring it right up to these edges that run here if we so desire and also i'm going to get rid of the golden surface which is here i've got a mirror in this golden surface because i've mirrored it over the other side so this is our golden surface that runs across here you could use loft if you so desire you can see what a number of curves going down and across so each of these sections has a curve and then each of these lines that denote the planks going across the boat are an interpolation curve so you can see them here reason why i've done them in groups is because it's really easy to copy these so when i do one sketch i can copy it with the curve and just move the sketch and the interpolation curve will move with it and what i'll do is to quickly demonstrate how i've done some of these so for that i'm going to create a new document i'm just going to close out the old ones and this one here and we'll create a new document and the first thing i'm going to do is come into the sketcher create a sketch and i'm going to place it along the zx plane so that'll be from the front so we're looking down here the zx plane zx plane and okay that i was working on the half breadth of the boat so half the boat i'm not going to worry about scale or constraints so we're going to be using the polyline and i'm going to create a number of lines going up like so let's go hit escape gain and i just can make these lines equal to each other using the quality constraint there obviously for the front one we don't want to anchor it at the point of origin because we want this to move or we could use this one here as our placement so rather having that one inequality if i take that out i've just got this one in quality and i've accidentally deleted that so let's add a line in here like so i can place this one under constraint and just in that will push this line up and down we now need our lines that the planks will connect to and we're just going to place those in here i'm going to place one more in here as well got the auto constraints which make this a lot easier so if i come down here you can see the auto constraints are on so whenever hover over anything that's going to connect to that place over there it's going to connect via point on line constraint or point on object constraint there i'm just going to put a horizontal constraint in here i'll use shortcut key strokes for this but i'm demonstrating so if i'm using shortcut keys you're not actually seeing what i'm doing so now we've got our first lot in we can add some construction geometry so for instance i want to place these in dead rise in other words place a constraint here and we're going to place this going all the way up so i want one two three and dead rise like so and we can connect these to this line and the same with this one here just a point on point constraint the other ones point our object constraint and we'll click on this one and make it into construction geometry this one here so that's construction geometry and make sure this one is connected by a point on line constraint or point on object constraint and then i may even add another one in here for the curve and i'm just going to use a simple circle in here and we're going to place that in here like so again this is going to be construction geometry and then attach these points to the circle like so so we've got those points now in radius to here and we can play about with stuff like tangency to here if we so desire so i've made this line tangent to this circle now and we get a nice shape this will differ depending on what boat shape you're actually making and this line here will be more or less i think it's called the shear line the top of this the very top of the boat just excuse my boat making knowledge i'm it's an art form that i'm not familiar with and i totally respect so we've got this line here and we've got the start of our hull let's just put some quality constraints in here as well and we've got this line we should have actually placed an equality constraint across here but that's fine we'll go for that for the time being let's close that so we've got the shape that we want to use for the side of our hull i'm going to come in here and create a group so we're going to create a group and i'm going to rename this to section one and there's reason why i do this and that's because if i place now if i go to the curse workbench and we're going to select all these vertices we can increase the point size of the sketch so coming to view come down and you'll see line color point color point size we increase this up we can see those points much more easily now and we can use these points like so selecting them going down and i'm going to select this point as well this one here and we use the interpolated set of points so we've got that curve running down there we can use that in a lot if we created many of these now i'm going to move this sketch into section one group and this interpolation curve into there as well because what can happen now if i highlight sketch one edit duplicate or control c okay that and obviously control v to paste it if you've using the shortcuts we've got this section two now so we've got section one which we can hide section two which you can hide they're both on top of each other and we've duplicated up the sketch and the curve and inside section two there's the sketch and the curve and this curve come down to the data if we look at what it's connected to we can see the point this is sketch 001 which is this one so we've created the copy of this and just paste it in here and everything's connected up fine which means we can come into the sketch look at the placement look at where we're going to place it we're going to place it along the y-axis so we're going to move it along this axis come down to the position and let's move that by 50 millimeters this way so let's move 50 millimeters if we click off you can see the curve has taken as well so we've got these two curves now and we can carry on with this so i'm going to control c okay that click control v got that one and we come down to the data on the sketch make sure we're on the sketch not the actual folder itself and let's change this to 100 millimeters gain come in control c the last one okay that control v the reason why i do a control c and v on the last one is because when we come into the sketch of the copied we've got the y copied over if we copy the first one then this will always be zero and we'll just have to keep on adjusting that just a little bit easier maybe more keystrokes but that's fine so now we've got those sections so i'm going to do four sections in here we can create another section over here by either copying this rotating it around or by creating a separate section on this side i'm going to leave that for now and i'm just going to concentrate on these so we've got now all of these going this way and i can select these points in the curse workbench this point here this point here and this one and again use the interplay curve across there that top one's gonna be obviously straight because they're all straight there but if we changed any of these sizes that will actually modify that curve so let's place one i will do it for all of these but for quickness i'm going to place one here as well let's just give you an idea of what you can use this for we may want to come in and actually hide these curves because they can get in the way while we're doing this like so and i'm gonna click on this one this one this one and this one and do the same and the same for these as well i should take the bottom one and interpolate that curve across they're all going to be basically straight at the moment but if we take say this sketch and also show the other interpolation curve so i'm clicking on them and pressing the spacebar to actually make them visible we've got those going through there we can take for instance this sketch here double click it and change these say like so close it and you can see we start to change the shape of our boat so i can take this one double click it and again change the shape of this bring this out and we've got basically the skeleton of our boats that we can actually change and modify and change the heights of these so for instance if i want to change the height of this one should be our first one and this is where this comes in handy so we can change this to say 20 millimeters i'll push this all up and close that let's push that up slightly now and from this we can make a curved surface through here so if i add one more in here going across here we can terminate that curved surface let's do that now so let's just hide pressing spacebar on these curves just to hide them so i can get to these points nicely if i wanted a flat bottom i can use a ruled surface going across but i'm just going to control click these and add another curve going across and bring back the interpolation curves going across here and we're missing one there's the other one this one here i can put the these curves going through the sections in a group if i so desire and now we've got those curves there always best to if we do any surfacing just save it we could use a loft through here we could either loft through the profiles going across here or going across here or we could use a golden surface across here so all of these curves let's go through the profiles first clicking on them control clicking so they're selected there and working our way up like so we can use the creative surface that skins the network curves and we've got our surface there and remembering that we can go into the sketch and modify that sketch moving these lines increasing or decreasing the width for the breadth of our hole or changing its shape throughout if we wasn't happy with a golden surface then we can press the spacebar on that we could use over in the part workbench we could just use a basic loft or even part design we can use a basic loft through here so if we come over to our utility to loft or part loft then we can go through the interpolation curves if we click on them you can see them highlighted in green there as we move through so i can use either the profiles like so okay that and loft through those profiles or we could use the rails or these lines that go across here and do the same so unfortunately if you click on here they don't highlight on the left hand side which is a shame so let's see if we can find those best ideas click off first and where are they that one that one that one and the last one and okay that and we've loft it through those rails going across there so we've gotten three different surfaces all different including the gordon and we can decide which one best fits our application remembering that also if we go onto the interpolation curve and we go down to our data we've got the options here to change the tolerance or how these curves fit those points at any time we want so i hope that helps just remember that the interpolation curve is different to the approximation curve if you use an approximation curve on a golden surface then those lines that create that approximation where they cross they may not actually join so they may not sit on top of each other that will break your golden surface if you're using an interpolation curve then you won't have that problem so just look out for that obviously that won't be the same if you're lofting through profiles through the normal part or part design i hope you enjoyed this video and i'll see you again soon if you like what you're seeing please subscribe to my site and also i have a kofi site where you can actually donate a few pence or a few pounds dollars or whatever your currency is and that's at ko hyphen fi.com slash ming0 and there you'll be able to help me fund my site and all the money that i actually get from any funds will actually get pushed back into the channel thanks a lot for watching and subscribing i'll see you next time

Channel: MangoJelly Solutions

Views: 2,126

Keywords: CAD, three, 3D, CNC, Printing, solidworks, autoCAD, morth, morph, merge, nurb, nerb, n.u.r.b.s, surface, modeling, boat, ship, lofting, loft

Id: g_O1wcZ7gr8

Length: 29min 23sec (1763 seconds)

Published: Wed Oct 20 2021