ut in the next few days.
I've found getting really good handling of static vs kinetic friction to be a pain though.
Distinguishing between collisions and resting contact generally becomes more complicated than it might first appear.
If the collision with the mesh or ground is 'hard' I project the particle positions, so they can never penetrate, and reverse the component of their velocity normal to the surface (multiplied by the restitution factor). This means that whenever you have some structure of springs resting on a hard surface, there is usually still some tiny imperceptible bouncing. This makes it hard to properly apply static friction (which would zero the tangential velocity if the tangential force was below some threshold and it is not already sliding), because particles are generally not perfectly on the surface, even when apparently at rest. Obviously it's not good to have friction affecting things that aren't touching the surface.
This is the origin of the 'settle' parameter in the settings. The idea was that when the motion of a particle normal to the surface drops below that limit, it will be totally zeroed, and the particle becomes properly resting on the surface. I never really like having to use these kind of weird ad hoc fixes though.
Alternatively, if the collision is 'soft' I use a spring-like force to push particles out of the ground/mesh.
This can cause problems because in many cases you just want a simple constraint that they never go below ground level, and there is a limit to how stiff you can make these spring-like forces.
The advantage though, is that because any particle resting 'on' the ground/surface will actually be slightly below/inside it, and one can use this to decide whether to apply contact friction.
With bouncing collisions, it is a little simpler. There is just the question of what to do with the velocity component tangential to the surface. See the bottom comment by me here, for more on the 'tumble' setting:
http://www.grasshopper3d.com/video/kangaroo-traction-test
So you see, it is challenging to get one consistent model that will give correct behaviour for all cases (eg a simple static 'leaning ladder' type problem, a bouncing particle, and vehicle wheel traction), without having several of these odd seeming and non-intuitive settings.
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Added by Daniel Piker at 11:11am on October 18, 2012
m is different from email spam.
Email spammers want you to buy their product. You are the target of the ad contained in each email spam you receive. Comment/web spammers want your readers to buy their product. You (the blogger, author, moderator) are not the target.
2. Web spammers are social engineers.
Email spammers write messages to get your attention. Comment spammers write messages to escape your attention. They want you to believe they are real bloggers, real people, writing real comments, so you’ll approve the comment and publish it on your site. They use flattery, appeal to your good nature, and simply lie in order to convince you to give them the benefit of the doubt.
3. Web spammers are basically advertising on your blog..
..and they're keeping all of the profits. They’re not even asking your permission first. Right now someone is offering to sell links from your blog to anyone willing to pay a few dollars (or a few cents). If your blog is well known, it may even be listed by name, with backlinks for sale at a set price.
4. It’s all about the backlinks.
Web spammers are selling links from your blog to their clients. They do this to game the search engines and trick your readers into visiting dubious web sites. Their clients are sometimes seemingly harmless, but are often peddling fake pills, porn, scams and malware. Sometimes they’ll use “buffer sites” – that is, innocent looking web pages intended to disguise the fact that they’re really advertising something more sinister.
5. Spammers employ humans.
Not all spam is delivered by spambots. Spammers are increasingly using humans to write and post comments by hand. Typically they are exploiting low-paid workers in internet cafes, schools and factories. Sometimes they are viral marketers paid to promote a new product. Either way they are trying to exploit your blog for their profit – and hoping to do it without you noticing.
…
Added by Danny Boyes at 4:51am on October 24, 2013
he results are accurate enough.Good to go!Current working directory is set to: C:\002_VIDEO\02_UNI\TU_GRAZ\01_DISSERTATION\02_RESEARCH\08_POMODORO\01_SIMULATION_MODEL/03_HONEYBEE\VF_00\gridBasedSimulation\start cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineRuntime error (IndexOutOfRangeException): index out of range: 0Traceback: line 271, in script…
is set to: C:\002_VIDEO\02_UNI\TU_GRAZ\01_DISSERTATION\02_RESEARCH\08_POMODORO\01_SIMULATION_MODEL/03_HONEYBEE\VF_00\gridBasedSimulation\start cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get Commandlinestart cmd /c C:\Users\paratufello\AppData\Roaming\Ladybug\unnamed\annualSimulation\unnamed_7_DS.batWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineWMIC PROCESS get CommandlineRuntime error (IndexOutOfRangeException): index out of range: 0Traceback: line 271, in script…
dy for a wall where we want to analyze its openings. I made a parametric wall that then get's analyzed with different geometries and the idea was just to leave it there for the weekend as it morphed through different iterations. However, after successfully running a test simulation on my pc (just with one iteration), it fails to run the same test on the workplace computer. Any help would be greatly apprecated! Here is the following error:
Sorry! But the number of available CPUs on your machine is 4.
Honeybee set the number of CPUs to 4.
Grid-based Radiance simulation
The component is checking ad, as, ar and aa values. This is just to make sure that the results are accurate enough.
Good to go!
Current working directory is set to: C:\ladybug\Parametric_Shading_Wall\psw_z0.25_t.025_y.2_r90_m3_lux\gridBasedSimulation\
Failed to read the results!
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
Runtime error (PythonException): Failed to read the results!
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
rtrace: fatal - (psw_z0.25_t.025_y.2_r90_m3_lux_RAD.oct): truncated octree
PS. It says to see line 336…
ed file and code below:
Color ColorAt(Mesh mesh, int faceIndex, double t0, double t1, double t2, double t3) { // int rc = -1; var color = Rhino.Display.Color4f.Black;
if( mesh.VertexColors.Count != 0) { // test to see if face exists if( faceIndex >= 0 && faceIndex < mesh.Faces.Count ) { /// Barycentric quad coordinates for the point on the mesh /// face mesh.Faces[FaceIndex].
/// If the face is a triangle /// disregard T[3] (it should be set to 0.0).
/// If the face is /// a quad and is split between vertexes 0 and 2, then T[3] /// will be 0.0 when point is on the triangle defined by vi[0], /// vi[1], vi[2]
/// T[1] will be 0.0 when point is on the /// triangle defined by vi[0], vi[2], vi[3].
/// If the face is a /// quad and is split between vertexes 1 and 3, then T[2] will /// be -1 when point is on the triangle defined by vi[0], /// vi[1], vi[3]
/// and m_t[0] will be -1 when point is on the /// triangle defined by vi[1], vi[2], vi[3].
MeshFace face = mesh.Faces[faceIndex];
// Collect data for barycentric evaluation. Color p0, p1, p2;
if(face.IsTriangle) { p0 = mesh.VertexColors[face.A]; p1 = mesh.VertexColors[face.B]; p2 = mesh.VertexColors[face.C]; } else { if( t3 == 0 ) { // point is on subtriangle {0,1,2} p0 = mesh.VertexColors[face.A]; p1 = mesh.VertexColors[face.B]; p2 = mesh.VertexColors[face.C]; } else if( t1 == 0 ) { // point is on subtriangle {0,2,3} p0 = mesh.VertexColors[face.A]; p1 = mesh.VertexColors[face.C]; p2 = mesh.VertexColors[face.D]; //t0 = t0; t1 = t2; t2 = t3; } else if( t2 == -1 ) { // point is on subtriangle {0,1,3} p0 = mesh.VertexColors[face.A]; p1 = mesh.VertexColors[face.B]; p2 = mesh.VertexColors[face.D]; //t0 = t0; //t1 = t1; t2 = t3; } else { // point must be on remaining subtriangle {1,2,3} p0 = mesh.VertexColors[face.B]; p1 = mesh.VertexColors[face.C]; p2 = mesh.VertexColors[face.D]; t0 = t1; t1 = t2; t2 = t3; } }
/** double r = t0 * p0.FractionRed() + t1 * p1.FractionRed() + t2 * p2.FractionRed(); double g = t0 * p0.FractionGreen() + t1 * p1.FractionGreen() + t2 * p2.FractionGreen(); double b = t0 * p0.FractionBlue() + t1 * p1.FractionBlue() + t2 * p2.FractionBlue();
ON_Color color; color.SetFractionalRGB(r, g, b);
unsigned int abgr = (unsigned int)color; rc = (int) ABGR_to_ARGB(abgr); **/ var c0 = new Rhino.Display.Color4f(p0); var c1 = new Rhino.Display.Color4f(p1); var c2 = new Rhino.Display.Color4f(p2); float s0 = (float) t0; float s1 = (float) t1; float s2 = (float) t2;
float R = s0 * c0.R + s1 * c1.R + s2 * c2.R; float G = s0 * c0.G + s1 * c1.G + s2 * c2.G; float B = s0 * c0.B + s1 * c1.B + s2 * c2.B; color = new Rhino.Display.Color4f(R, G, B, 1); } } return color.AsSystemColor(); }
…
ort and export from the images below and also from the HELP file of DB in attachments (Page 71: Importing Geometric Data; Page 78-80: Import 3 - D CAD Data). In their HELP file, they mention about "import geometric data".
However, regarding the input of schedules, loads, constructions and etc., DB normally uses "Component " and "Template" (Page 29: Templates And Components; Page 591: Templates; Page 533: Components). "Templates" are databases of typical generic data, including Activity templates, Construction templates, Glazing templates, Facade templates, HVAC templates, Location Templates, and etc. "Component " are databases of individual data items (e.g. a construction type, material, window pane).
Both "Component " and "Template" are allowed to be imported and exported by using "Import / Export library data" command (.ddf format - DB Database File; Page 734: Import Components/Templates, Export Components/Templates). DB also allows us to build up our own libraries of templates and components (Page 731: Library Management; Page 733: Template Library Management).
In order to import both geometric information and other information related to schedules, loads, constructions and etc. from GH to BD, we supposed the following two ways:
1. GH(HB+GB) --> gbXML (both geometric and "Component " and "Template" information) --> DB
This is the way we most prefer. We did see information related to schedules, loads, constructions encoded in the gbXML file generated by GB, but still do not know the reason why DB did not take this information (I also mentioned this in Q6 within the gh file). We assume this might because the gbXML file we create encodes the schedules based on a different template / schema than the one DB expects. We also post this question to the DB forum for help.
(http://www.designbuilder.co.uk/component/option,com_forum/Itemid,25/page,viewtopic/p,13755/#13755)
2. GH(HB+GB) --> gbXML (geometric information only) + .ddf ("Component " and "Template" information only) --> DB
If the first way doesn't work and DB only takes geometric information from the gbXML, then we might think of the other way - generating the .ddf files from GH(HB+GB) to pass the schedule, load and construction information to DB.
I was wondering if it is feasible for HB and GB to have this function? And what is your suggestion to achieve this?
In addition, we notice that DB can export XML files (not gbXML), so we are trying to figure out if DB also accepts / reads the XML file. If so, we might be able to convert the gbXML (with both geometric and schedule information) to XML. What do you think about that?
Thank you again for all your help!
Best,
Ding
DB import
DB export
Template libraries
Component libraries
…
ay how many valid permutations exist.
But allow me to guesstimate a number for 20 components (no more, no less). Here are my starting assumptions:
Let's say the average input and output parameter count of any component is 2. So we have 20 components, each with 2 inputs and 2 outputs.
There are roughly 35 types of parameter, so the odds of connecting two parameters at random that have the same type are roughly 3%. However there are many conversions defined and often you want a parameter of type A to seed a parameter of type B. So let's say that 10% of random connections are in fact valid. (This assumption ignores the obvious fact that certain parameters (number, point, vector) are far more common than others, so the odds of connecting identical types are actually much higher than 3%)
Now even when data can be shared between two parameters, that doesn't mean that hooking them up will result in a valid operation (let's ignore for the time being that the far majority of combinations that are valid are also bullshit). So let's say that even when we manage to pick two parameters that can communicate, the odds of us ending up with a valid component combo are still only 1 in 2.
We will limit ourselves to only single connections between parameters. At no point will a single parameter seed more than one recipient and at no point will any parameter have more than one source. We do allow for parameters which do not share or receive data.
So let's start by creating the total number of permutations that are possible simply by positioning all 20 components from left to right. This is important because we're not allowed to make wires go from right to left. The left most component can be any one of 20. So we have 20 possible permutations for the first one. Then for each of those we have 19 options to fill the second-left-most slot. 20×19×18×17×...×3×2×1 = 20! ~2.5×1018.
We can now start drawing wires from the output of component #1 to the inputs of any of the other components. We can choose to share no outputs, output #1, output #2 or both with any of the downstream components (19 of them, with two inputs each). That's 2×(19×2) + (19×2)×(19×2-1) ~ 1500 possible connections we can make for the outputs of the first component. The second component is very similar, but it only has 18 possible targets and some of the inputs will already have been used. So now we have 2×(18×2-1) + (18×2-1)×(18×2-1) ~1300. If we very roughly (not to mention very incorrectly, but I'm too tired to do the math properly) extrapolate to the other 18 components where the number of possible connections decreases in a similar fashion thoughout, we end up with a total number of 1500×1300×1140×1007×891×789×697×...×83×51×24×1 which is roughly 6.5×1050. However note that only 10% of these wires connect compatible parameters and only 50% of those will connect compatible components. So the number of valid connections we can make is roughly 3×1049.
All we have to do now is multiply the total number of valid connection per permutation with the total number of possible permutations; 20! × 3×1049 which comes to 7×1067 or 72 unvigintillion as Wolfram|Alpha tells me.
Impressive as these numbers sound, remember that by far the most of these permutations result in utter nonsense. Nonsense that produces a result, but not a meaningful one.
EDIT: This computation is way off, see this response for an improved estimate.
--
David Rutten
david@mcneel.com
Poprad, Slovakia…
Added by David Rutten at 12:06pm on March 15, 2013
te some cut sheets, but not to optmize material, rather define some cut lines. Everything that I am cutting is made of planar wood elements, but there are very specific geometries (mostly straight lines) and I have to put tolerances and radiasas at the corners in order to cut on the cnc mill. Spending time to figure out how to automate is necessary, but I am stuck!
One thing the definition is doing is taking my brep modeled components in rhino and makking them into 2d close curves and laying them side by side. It works...not ideal as its not layed out in a sheet, but that is not the most important part.
Another particular problem is that you will see some notches in the curves, which other pieces will slip into, so different slots need different specific offsets (making them larger) as a toelrance to allow for material play. This I don't even know how to set up so maybe it will just have to wait.
THE MAIN QUESTION, and super important would be, LIFESAVER:
At all 'inward' corners...which I think will always mean concave corners (most are 90 degrees, but are within to sides, instead of a corner sticking out). I'm sure its obviousy, but the reason being the outward corners a circular dril bit can cut, but inward ones need an arc profile extended beyond where the corner of the other piece will fit into. The drill bit i am using is 6mm, so 6mm diamters arcs is what i'm working with.
I have managed to put such an arc at every vertices of each cut piece. The problem being some stick outward isntead of cutting into the piece. So each one needs to be orieneted correctly. Ideally they would also only draw into inward corners, but I can always delete them out. I think maybe I am missing a more logical mathematical way of defining?
For these geometries it is not very important which side the half circle arc in on in the inward corners, but I also have some geometries that I will have to control where the circles face according to the rest of the cut piece.
The cutouts in the middle of the pieces that are curves do not need such corners obviously.
The picture is an example drawn
I hope this isn't too specific and long. in general though automating fabrication, and controling pracitcal math and orientation problems like this is itnersting to me!
THANKS…
tema della modellazione parametrica con Grasshopper. Questa plug-in di Rhino consente di progettare, confrontandosi con un contesto evolutivo, attraverso la comprensione e l'utilizzo di parametri e componenti che influenzano la rappresentazione e la rendono dinamica componendo algoritmi. Nel corso verranno introdotte le nozioni base di Grasshopper approfondendo le metodologie della progettazione parametrica e le tecniche di modellazione algoritmica per la generazione di forme complesse.
Le informazioni teoriche saranno fornite in maniera accelerata ma organica e contestuale agli argomenti elencati. Per massimizzare i risultati, le lezioni saranno accompagnate da piccole esercitazioni pratiche.Argomenti trattati:- Introduzione alla progettazione parametrica: teoria, esempi, casi studio- Grasshopper: concetti base, logica algoritmica, interfaccia grafica- Nozioni fondamentali: componenti, connessioni, data flow- Funzioni matematiche e logiche, serie, gestione dei dati- Analisi e definizione di curve e superfici- Definizione di griglie e pattern complessi- Trasformazioni geometriche, paneling- Attrattori, image sampler- Data tree: gestione di dati complessiStrutturaIl corso ha una durata di 16 ore programmate nell'arco di 2 giornate con i seguenti orari: i giorni 10/11 e 11/11 dalle 10,00 alle 19,00 con pausa pranzo di un'ora.
PrerequisitiPer affrontare il corso è richiesta una conoscenza di base del software Rhino attraverso esperienze teoriche e pratiche. I partecipanti dovranno venire muniti di proprio laptop e con software Rhinoceros 5 o Rhinocero 4 perfettamente funzionanti.Alla fine del corso, verrà rilasciato l’attestato di partecipazione ad un corso qualificato certificato dalla McNeel, valido anche per l’ottenimento di crediti formativi universitari.
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