nts for Ladybug too. They are based on PVWatts v1 online calculator, supporting crystalline silicon fixed tilt photovoltaics.
You can download them from here, or use the Update Ladbybug component instead. If you take the first option, after downloading check if .ghuser files are blocked (right click -> "Properties" and select "Unblock").
You can download the example files from here.
Video tutorials will follow in the coming period.
In the very essence these components help you answer the question: "How much energy can my roof, building facade, solar parking... generate if I would populate them with PV panels"?
They allow definition of different types of losses (snow, age, shading...) which may affect your PV system:
And can find its optimal tilt and orientation:
Or analyse its performance, energy value, consumption, emissions...
By Djordje Spasic and Jason Sensibaugh, with invaluable support of Dr. Frank Vignola, Dr. Jason M. Keith, Paul Gilman, Chris Mackey, Mostapha Sadeghipour Roudsari, Niraj Palsule, Joseph Cunningham and Christopher Weiss.
Thank you for reading, and hope you will enjoy using the components!
EDIT: From march 27 2017, Ladybug Photovoltaics components support thin-film modules as well.
References:
1) System losses:
PVWatts v5 Manual, Dobos, NREL, 2014
2) Sun postion equations by Michalsky (1988):
SAM Photovoltaic Model Technical Reference, Gilman, NREL, 2014
edited by Jason Sensibaugh
3) Angle of incidence for fixed arrays:
PVWatts Version 1 Technical Reference, Dobos, NREL, 2013
4) Plane-of-Array diffuse irradiance by Perez 1990 algorithm:
PVPMC Sandia National Laboratories
SAM Photovoltaic Model Technical Reference, Gilman, NREL, 2014
5) Sandia PV Array Performance Module Cover:
PVWatts Version 1 Technical Reference, Dobos, NREL, 2013
6) Sandia Thermal Model, Module Temperature and Cell Temperature Models:
Photovoltaic Array Performance Model, King, Boys, Kratochvill, Sandia National Laboratories, 2004
7) CEC Module Model: Maximum power voltage and Maximum power current from:
Exact analytical solutions of the parameters of real solar cells using Lambert W-function, Jain, Kapoor, Solar Energy Materials and Solar Cells, V81 2004, P269–277
8) PVFORM version 3.3 adapted Module and Inverter Models:
PVWatts Version 1 Technical Reference, Dobos, NREL, 2013
9) Sunpath diagram shading:
Using sun path charts to estimate the effects of shading on PV arrays, Frank Vignola, University of Oregon, 2004
Instruction manual for the Solar Pathfinder, Solar Pathfinder TM, 2008
10) Tilt and orientation factor:
Application for Purchased Systems Oregon Department of Energy
solmetric.com
11) Photovoltaics performance metrics:
Solar PV system performance assessment guideline, Honda, Lechner, Raju, Tolich, Mokri, San Jose state university, 2012
CACHE Modules on Energy in the Curriculum Solar Energy, Keith, Palsule, Mississippi State University
Inventory of Carbon & Energy (ICE) Version 2.0, Hammond, Jones, SERT University of Bath, 2011
The Energy Return on Energy Investment (EROI) of Photovoltaics: Methodology and Comparisons with Fossil Fuel Life Cycles, Raugei, Fullana-i-Palmer, Fthenakis, Elsevier Vol 45, Jun 2012
12) Calculating albedo: Metenorm 6 Handbook part II: Theory, Meteotest 2007
13) Magnetic declination:
Geomag 0.9.2015, Christopher Weiss…
he "return" is comment out as shown below?
After restarting Rhino and Grasshopper, I opened the outdoors_airflow demo file, and the first step of creating the case file is ok:
Then the blockMesh component gives the following error: seems I have to manually start OF first..
so, as the error message suggested, I open OF by Start_OF.bat:
Then come back to the blockMesh component, now it can be executed while the OF command line window is also openning:
... and the blockMesh finished successfully:
... so I proceeded to run snappyHexMesh, checkMesh and update fvScheme:
... up to the simpleFoam component, I got the error again:
The warning message is:
1. Solution exception: --> OpenFOAM command Failed!#0 Foam::error::printStack(Foam::Ostream&) in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #1 Foam::sigFpe::sigHandler(int) in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #2 ? in "/lib64/libc.so.6" #3 double Foam::sumProd<double>(Foam::UList<double> const&, Foam::UList<double> const&) in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #4 Foam::PCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #5 Foam::GAMGSolver::solveCoarsestLevel(Foam::Field<double>&, Foam::Field<double> const&) const in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #6 Foam::GAMGSolver::Vcycle(Foam::PtrList<Foam::lduMatrix::smoother> const&, Foam::Field<double>&, Foam::Field<double> const&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::PtrList<Foam::Field<double> >&, Foam::PtrList<Foam::Field<double> >&, unsigned char) const in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #7 Foam::GAMGSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so" #8 Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/lib/libfiniteVolume.so" #9 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/bin/simpleFoam" #10 Foam::fvMatrix<double>::solve() in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/bin/simpleFoam" #11 ? in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/bin/simpleFoam" #12 __libc_start_main in "/lib64/libc.so.6" #13 ? in "/opt/OpenFOAM/OpenFOAM-v1606+/platforms/linux64GccDPInt32Opt/bin/simpleFoam"
... and the command lines in the readMe! output are pretty long and it is saved in the text file attached here.
So, my questions are:
1. why I have to manually start OF first before I can use the blockMesh component? Should butterfly automatically start OF?
2. what might be the cause of the unsuccessful run of simpleFoam in the end?
Hope you can kindly advise! Thank you!
- Ji
…
analysis with Honeybee. Here is the tentative outline:
09:00 - 09:30
What is Honeybee, Introduction to daylighting simulation
09:30 - 11:00
Geometry preparation workflows, Radiance materials
11:00 - 11:10
Break
11:10 - 12:30
Sky types, Run your first simulation
12:30 - 13:30
Lunch
13:30 - 15:00
Daylighting analysis types, Result visualization, Getting started with annual daylight
15:00 - 15:15
Break
15:15 - 16:00
Annual daylight analysis and Results interpretation
Check MEBD page for more information including the registration link: http://www.mebd-penndesign.info/Honeybee-MEBD-Workshop-PennDesign
Please feel free to forward this to anyone of interest.
Cheers,
Mostapha
PS: Thank you all for the kind comments and emails for the Ladybug workshop. We recorded the workshop and are in the process of figuring out how to share it with the public. I will send an update once it is uploaded.
…
teraction for its Correlations cycle, AA Athens Visiting School scales up its design intentions in order to investigate links among discrete individual architectural systems in its 2013 version, Recharged.
Recharged with interconnectivity on different levels, the theme of investigation will revolve around the design of semi-independent design prototypes acting together to form elaborate unified results. The driving force in Cipher City: Recharged is the synergistic effect behind complex form-making systems where interactive design patterns arise out of a multiplicity of relatively simple rules.
In collaboration with the National Technical University of Athens, Cipher City: Recharged will explore participatory design and active engagement modeling and will continue building novel prototypes upon horizontal planes.
As in 2012, the design agendas of AA Athens and AA Istanbul Visiting Schools will directly create feedback on one another, allowing participation in either one or both Programmes.
Discounts
The AA offers several discount options for participants wishing to apply as a group or participants wishing to apply for both AA Istanbul and AA Athens Visiting Schools:
1. Standard application
The AA Visiting School requires a fee of £695 per participant, which includes a £60 Visiting Membership. If you are already a member, the total fee will be reduced automatically by £60 by the online payment system. Fees are non refundable.
2. Group registration
For group applications, there will be a range of discounts depending on the number of people in the group. The discounted fee will be applied to each individual in the group.
Type A. 3-6 people group: £60 (AA Membership fee) + 635*0.75 = £536.25 (25 %) Type B. 6-15 people group: £60 + 635*0.70 = £504.5 (30%) Type C. more than 15 people group: £60 + 635*0.65 = £472.75 (35%)
3. Participants attending both AA Istanbul and AA Athens | 40% discount
For people wishing to attend both AA Istanbul 2013 and AA Athens 2013, a discount of 40% will be made for each participant. (The participant will pay the £60 membership fee only once.)
£60 (AA Membership fee) + (635*0.60)*2 = £822
For more information in discounts, please visit:
http://ai.aaschool.ac.uk/athens/portfolio/discounts-2013/
Applications
The deadline for applications is 11 March 2013. A portfolio or CV is not required, only the online application form and payment. The online application can be reached from:
http://www.aaschool.ac.uk/STUDY/VISITING/athens…
Added by elif erdine at 12:33pm on December 13, 2012
. From the Thermal Comfort Indices component, Comfort Index 11 (TCI-11):MRT = f(Ta, Tground, Rprim, e)
with:- Ta = DryBulbTemperature coming from ImportEPW component- Tground = f(Ta, N) where N comes from totalSkyCover input. Tground influences the long-wave radiation emitted by the ground in the MRT calculation.- Rprim defined as solar radiation absorbed by nude man = f(Kglob, hS1, ac)- ac is the clothingAlbedo in % (bodyCharacteristics input)- I can't find any definition in the code of Kglob and hS1. Could you tell me please what are those values referencered to? --> probably the globalHorizontalRadiation but how?- e = vapour pressure calculated from Ta and Relative Humidity input
Do you agree that in this case the MRT does not depend on these inputs: location, meanRadiantTemperature, dewPointTemperature and wind speed?It does not depend neither on the other bodyCharacteristics like bodyPosture, age, sex, met, activityDuration...?
MRT calculated by the TCI-11 method is the mean radiant temperature of a vector pointing vertically with a sky view factor of 100%?For ParisOrly epw,
2. From the SolarAdjustedTemperature component (that seems to be more used for the UTCI calculation examples on Hydra compared to TCI-11).
In contrast to the TCI-11, this component distinguishes diffuse and direct radiation and contextualizes the calculation thanks to _ContextShading input, right? It can also be applied to a mannequin thanks to the CumSkyMatrix and thus evaluate the dishomogeneity of radiation exposure.This component seems not to consider the influence of vapour pressure on the result --> is it then more precise to put the MRT output (from the TCI) as an input of meanRadTemperature for SolarAdjustedTemperature?The default groundReflectivity is set to 0.25 --> is GroundReflectivity taken into account in the Tground or MRT calculation in the TCI component? If yes, what is the hypothesised groundReflectivity?The default clothing albedo of 37% (TCI-11 bodyCharacteristics) corresponds to Clothing Absorptivity of 63%?
If the CumSkyMatrix input is not supplied, I get 9 results for the mannequin --> where are those points/results coming from?
If the CumSkyMatrix input is supplied,I suppose the calculation of the 482 results correspond to a calculation method similar to the radiation analysis component that is averaged over the analysis period. Right?But I don't understand why the mannequin is composed of 481 faces and meshFaceResult gives 482 results.
Finally, what is the link between the MESH results, the solarAdjustedMRT and the Effective Radiant field ? Is there a paper to have a detailed explanation of the method?
3. Here are some results for the ParisOrly energyplus weather data. You can find here attached the grasshopper definition.There is no shading in this simulation and the result coming from the ThermalComfort indices for MRT is very different compared to the solar adjusted MRT.Why such a big difference and which of the result should be plugged into the UTCI calculation component?
Results for ParisOrly.epwM,D,H:1,1,12
Ta : 6.5°Crh: 100%globalHorizontalRadiation: 54 Wh/m2totalSkyCover: 10MRT (TCI-11): 1.2°C
_CumSkyMtxOrDirNormRad = directNormalRadiation : 0 Wh/m2diffuseHorizontalRad: 54 Wh/m2_meanRadTemp = TasolarAdjustedMRT: 10.64°CMRTDelta: 4.14°C
_CumSkyMtxOrDirNormRad = CumulativeSkyMtxdiffuseHorizontalRad: 54 Wh/m2_meanRadTemp = TasolarAdjustedMRT: 10.47°CMRTDelta: 3.97°C
_CumSkyMtxOrDirNormRad = CumulativeSkyMtxdiffuseHorizontalRad: 54 Wh/m2_meanRadTemp = MRT (TCI-11)solarAdjustedMRT: 5.17°CMRTDelta: 3.97°C
Thanks a lot for your helpRegards,
Aymeric
…
is set up to manipulate strings into an STL file that is quite different from how Grasshopper defines meshes, in that an STL seems to define each face by XYZ points, Grasshopper wants a single list of all vertex points and then has an allied lists of topological connectivity according to vertex number, so for now I just hacked it to spit out points minus so many duplicates it generates for STL:
Right now it has an internal 3D trigonometric function I added input sliders to control, that creates surfaces that look a lot like molecular orbitals.
So how do I make a mesh? I failed to make a single mesh face from each STL face since AddMesh seems to want a list, so I tried making a single list and matching it with a simple ((1,2,3),(4,5,6),(7,8,9)...) array of connectivity but it hasn't worked yet since the STL list of vertices has duplicates that won't work for Grasshopper and removing the duplicates scrambles the connectivity relation.
After some work on this and seeing the output, I figure I could just randomly populate the mathematical function with points instead, unless it really gives a better mesh result than other routines. I'm not sure what to do with it yet, even if I get the mesh figured out.
import rhinoscriptsyntaximport RhinoPOINTS_CONTAINER =[]POINTS = []class Vector: # struct XYZ def __init__(self,x,y,z): self.x=x self.y=y self.z=z def __str__(self): return str(self.x)+" "+str(self.y)+" "+str(self.z) class Gridcell: # struct GRIDCELL def __init__(self,p,n,val): self.p = p # p=[8] self.n = n # n=[8] self.val = val # val=[8] class Triangle: # struct TRIANGLE def __init__(self,p1,p2,p3): self.p = [p1, p2, p3] # vertices # HACK TO GRAB VERTICES FOR PYTHON OUTPUT POINTS_CONTAINER.append( (p1.x,p1.y,p1.z) ) POINTS_CONTAINER.append( (p2.x,p2.y,p2.z) ) POINTS_CONTAINER.append( (p3.x,p3.y,p3.z) )# return a 3d list of values def readdata(f=lambda x,y,z:x*x+y*y+z*z,size=5.0,steps=11): m=int(steps/2) ki = [] for i in range(steps): kj = [] for j in range(steps): kd=[] for k in range(steps): kd.append(f(size*(i-m)/m,size*(j-m)/m,size*(k-m)/m)) kj.append(kd) ki.append(kj) return ki from math import sin,cos,exp,atan2 def lobes(x,y,z): try: theta = atan2(x,y) # sin t = o except: theta = 0 try: phi = atan2(z,y) except: phi = 0 r = x*x+y*y+z*z ct=cos(PARAMETER_A * theta) cp=cos(PARAMETER_B * phi) return ct*ct*cp*cp*exp(-r/10) def main(): data = readdata(lobes,10,40) isolevel = 0.1 #print(data) triangles=[] for i in range(len(data)-1): for j in range(len(data[i])-1): for k in range(len(data[i][j])-1): p=[None]*8 val=[None]*8 #print(i,j,k) p[0]=Vector(i,j,k) val[0] = data[i][j][k] p[1]=Vector(i+1,j,k) val[1] = data[i+1][j][k] p[2]=Vector(i+1,j+1,k) val[2] = data[i+1][j+1][k] p[3]=Vector(i,j+1,k) val[3] = data[i][j+1][k] p[4]=Vector(i,j,k+1) val[4] = data[i][j][k+1] p[5]=Vector(i+1,j,k+1) val[5] = data[i+1][j][k+1] p[6]=Vector(i+1,j+1,k+1) val[6] = data[i+1][j+1][k+1] p[7]=Vector(i,j+1,k+1) val[7] = data[i][j+1][k+1] grid=Gridcell(p,[],val) triangles.extend(PolygoniseTri(grid,isolevel,0,2,3,7)) triangles.extend(PolygoniseTri(grid,isolevel,0,2,6,7)) triangles.extend(PolygoniseTri(grid,isolevel,0,4,6,7)) triangles.extend(PolygoniseTri(grid,isolevel,0,6,1,2)) triangles.extend(PolygoniseTri(grid,isolevel,0,6,1,4)) triangles.extend(PolygoniseTri(grid,isolevel,5,6,1,4)) def t000F(g, iso, v0, v1, v2, v3): return [] def t0E01(g, iso, v0, v1, v2, v3): return [Triangle( VertexInterp(iso,g.p[v0],g.p[v1],g.val[v0],g.val[v1]), VertexInterp(iso,g.p[v0],g.p[v2],g.val[v0],g.val[v2]), VertexInterp(iso,g.p[v0],g.p[v3],g.val[v0],g.val[v3])) ] def t0D02(g, iso, v0, v1, v2, v3): return [Triangle( VertexInterp(iso,g.p[v1],g.p[v0],g.val[v1],g.val[v0]), VertexInterp(iso,g.p[v1],g.p[v3],g.val[v1],g.val[v3]), VertexInterp(iso,g.p[v1],g.p[v2],g.val[v1],g.val[v2])) ] def t0C03(g, iso, v0, v1, v2, v3): tri=Triangle( VertexInterp(iso,g.p[v0],g.p[v3],g.val[v0],g.val[v3]), VertexInterp(iso,g.p[v0],g.p[v2],g.val[v0],g.val[v2]), VertexInterp(iso,g.p[v1],g.p[v3],g.val[v1],g.val[v3])) return [tri,Triangle( tri.p[2], VertexInterp(iso,g.p[v1],g.p[v2],g.val[v1],g.val[v2]), tri.p[1]) ] def t0B04(g, iso, v0, v1, v2, v3): return [Triangle( VertexInterp(iso,g.p[v2],g.p[v0],g.val[v2],g.val[v0]), VertexInterp(iso,g.p[v2],g.p[v1],g.val[v2],g.val[v1]), VertexInterp(iso,g.p[v2],g.p[v3],g.val[v2],g.val[v3])) ] def t0A05(g, iso, v0, v1, v2, v3): tri = Triangle( VertexInterp(iso,g.p[v0],g.p[v1],g.val[v0],g.val[v1]), VertexInterp(iso,g.p[v2],g.p[v3],g.val[v2],g.val[v3]), VertexInterp(iso,g.p[v0],g.p[v3],g.val[v0],g.val[v3])) return [tri,Triangle( tri.p[0], VertexInterp(iso,g.p[v1],g.p[v2],g.val[v1],g.val[v2]), tri.p[1]) ] def t0906(g, iso, v0, v1, v2, v3): tri=Triangle( VertexInterp(iso,g.p[v0],g.p[v1],g.val[v0],g.val[v1]), VertexInterp(iso,g.p[v1],g.p[v3],g.val[v1],g.val[v3]), VertexInterp(iso,g.p[v2],g.p[v3],g.val[v2],g.val[v3])) return [tri, Triangle( tri.p[0], VertexInterp(iso,g.p[v0],g.p[v2],g.val[v0],g.val[v2]), tri.p[2]) ] def t0708(g, iso, v0, v1, v2, v3): return [Triangle( VertexInterp(iso,g.p[v3],g.p[v0],g.val[v3],g.val[v0]), VertexInterp(iso,g.p[v3],g.p[v2],g.val[v3],g.val[v2]), VertexInterp(iso,g.p[v3],g.p[v1],g.val[v3],g.val[v1])) ] trianglefs = {7:t0708,8:t0708,9:t0906,6:t0906,10:t0A05,5:t0A05,11:t0B04,4:t0B04,12:t0C03,3:t0C03,13:t0D02,2:t0D02,14:t0E01,1:t0E01,0:t000F,15:t000F} def PolygoniseTri(g, iso, v0, v1, v2, v3): triangles = [] # Determine which of the 16 cases we have given which vertices # are above or below the isosurface triindex = 0; if g.val[v0] < iso: triindex |= 1 if g.val[v1] < iso: triindex |= 2 if g.val[v2] < iso: triindex |= 4 if g.val[v3] < iso: triindex |= 8 return trianglefs[triindex](g, iso, v0, v1, v2, v3) def VertexInterp(isolevel,p1,p2,valp1,valp2): if abs(isolevel-valp1) < 0.00001 : return(p1); if abs(isolevel-valp2) < 0.00001 : return(p2); if abs(valp1-valp2) < 0.00001 : return(p1); mu = (isolevel - valp1) / (valp2 - valp1) return Vector(p1.x + mu * (p2.x - p1.x), p1.y + mu * (p2.y - p1.y), p1.z + mu * (p2.z - p1.z)) if __name__ == "__main__": main() # GRASSHOPPER PYTHON OUTPUTPOINTS = rhinoscriptsyntax.AddPoints(POINTS_CONTAINER)POINTS = rhinoscriptsyntax.CullDuplicatePoints(POINTS)…
as one element.
Thank you
Comment by karamba on October 7, 2014 at 11:27pm
Hello Patricio, divide the beams in such a way that each boundary vertex of the shell becomes an endpoint of a beam segment.
Best, Clemens
Comment by Llordella Patricio on October 8, 2014 at 8:30amDelete Comment
Hi Clemens,
I did what you suggested but now assemble element doesn´t work properly. Could you please tell me how to fix it? Thanks in advance, Patricio
8-10-14losa%20cadena.gh
Comment by karamba on October 8, 2014 at 11:59am
Hi Patricio, if you flatten the 'Elem'-input at the 'Assemble'-component the definition works. The triangular shell elements have linear displacement interpolations whereas the beam deflections are exact. In order to get correct results you should refine the shell mesh.
Best, Clemens
Comment by Llordella Patricio on October 9, 2014 at 8:35amDelete Comment
Hello, succeeds in creating the mesh to the slab, and built the beam segment, but when I see the deformations are not expected because the beam is deformed as the slab.
Thanks for the help
PS: maybe I'm using the program for a type of structure that is not the most appropriate, as I saw in the examples of other structures. But this type of structure is that students taught
best regards
Patricio
9-10-14%20Example%201.gh
Comment by karamba on October 9, 2014 at 10:46am
You could use the 'Mesh Edges'-component to retrieve the naked edges and turn them into beams - see attached file:91014Example1_cp.gh
Best regards,
Clemens
Comment by Llordella Patricio on October 15, 2014 at 3:41pmDelete Comment
Dear clemens
I was doing a rough estimate of the deformation, and I can not achieve the same result with Karamba. When I make a rough estimate of the result with Karamba beams and mine are very similar, I think the problem is when I connect the shell, because there are no similar results.
I sent the GH file, and an image of the calculation
The structure is concrete The result I get is 0.58cm
thank youPatricio
15-10-14%20Example.gh
Comment by karamba yesterday
Dear Patricio,
try to increase the number of shell elements. As mentioned in the manual they are linear elements. A mesh that is too coarse leads to a response which is stiffer than the real structure.
Best,
Clemens
…
t file** - ply file with just x,y,z locations. I got it from a 3d scanner. Here is how first few lines of file looks like - ply format ascii 1.0 comment VCGLIB generated element vertex 6183 property float x property float y property float z end_header -32.3271 -43.9859 11.5124 -32.0631 -43.983 11.4945 12.9266 -44.4913 28.2031 13.1701 -44.4918 28.2568 13.4138 -44.4892 28.2531 13.6581 -44.4834 28.1941 13.9012 -44.4851 28.2684 ... ... ... In case you need the data - please email me on **nisha.m234@gmail.com**. **Algorithm:** I am trying to find principal curvatures for extracting the ridges and valleys. The steps I am following is: 1. Take a point x 2. Find its k nearest neighbors. I used k from 3 to 20. 3. average the k nearest neighbors => gives (_x, _y, _z) 4. compute covariance matrix 5. Now I take eigen values and eigen vectors of this covariance matrix 6. I get u, v and n here from eigen vectors. u is a vector corresponding to largest eigen value v corresponding to 2nd largest n is 3rd smallest vector corresponding to smallest eigen value 7. Then for transforming the point(x,y,z) I compute matrix T T = [ui ] [u ] [x - _x] [vi ] = [v ] x [y - _y] [ni ] [n ] [z - _z] 8. for each i of the k nearest neighbors:<br> [ n1 ] [u1*u1 u1*v1 v1*v1] [ a ]<br> [ n2 ] = [u2*u2 u2*v2 v2*v2] [ b ] <br> [... ] [ ... ... ... ] [ c ] <br> [ nk ] [uk*uk uk*vk vk*vk]<br> Solve this for a, b and c with least squares 9. this equations will give me a,b,c 10. now I compute eigen values of matrix [a b b a ] 11. This will give me 2 eigen values. one is Kmin and another Kmax. **My Problem:** The output is no where close to finding the correct Ridges and Valleys. I am totally Stuck and frustrated. I am not sure where exactly I am getting it wrong. I think the normal's are not computed correctly. But I am not sure. I am very new to graphics programming and so this maths, normals, shaders go way above my head. Any help will be appreciated. **PLEASE PLEASE HELP!!** **Resources:** I am using Visual Studio 2010 + Eigen Library + ANN Library. **Other Options used** I tried using MeshLab. I used ball pivoting triangles remeshing in MeshLab and then applied the polkadot3d shader. If correctly identifies the ridges and valleys. But I am not able to code it. **My Function:** //the function outputs to ply file void getEigen() { int nPts; // actual number of data points ANNpointArray dataPts; // data points ANNpoint queryPt; // query point ANNidxArray nnIdx;// near neighbor indices ANNdistArray dists; // near neighbor distances ANNkd_tree* kdTree; // search structure //for k = 25 and esp = 2, seems to got few ridges queryPt = annAllocPt(dim); // allocate query point dataPts = annAllocPts(maxPts, dim); // allocate data points nnIdx = new ANNidx[k]; // allocate near neigh indices dists = new ANNdist[k]; // allocate near neighbor dists nPts = 0; // read data points ifstream dataStream; dataStream.open(inputFile, ios::in);// open data file dataIn = &dataStream; ifstream queryStream; queryStream.open("input/query.
pts", ios::in);// open data file queryIn = &queryStream; while (nPts < maxPts && readPt(*dataIn, dataPts[nPts])) nPts++; kdTree = new ANNkd_tree( // build search structure dataPts, // the data points nPts, // number of points dim); // dimension of space while (readPt(*queryIn, queryPt)) // read query points { kdTree->annkSearch( // search queryPt, // query point k, // number of near neighbors nnIdx, // nearest neighbors (returned) dists, // distance (returned) eps); // error bound double x = queryPt[0]; double y = queryPt[1]; double z = queryPt[2]; double _x = 0.0; double _y = 0.0; double _z = 0.0; #pragma region Compute covariance matrix for (int i = 0; i < k; i++) { _x += dataPts[nnIdx[i]][0]; _y += dataPts[nnIdx[i]][1]; _z += dataPts[nnIdx[i]][2]; } _x = _x/k; _y = _y/k; _z = _z/k; double A[3][3] = {0,0,0,0,0,0,0,0,0}; for (int i = 0; i < k; i++) { double X = dataPts[nnIdx[i]][0]; double Y = dataPts[nnIdx[i]][1]; double Z = dataPts[nnIdx[i]][2]; A[0][0] += (X-_x) * (X-_x); A[0][1] += (X-_x) * (Y-_y); A[0][2] += (X-_x) * (Z-_z); A[1][0] += (Y-_y) * (X-_x); A[1][1] += (Y-_y) * (Y-_y); A[1][2] += (Y-_y) * (Z-_z); A[2][0] += (Z-_z) * (X-_x); A[2][1] += (Z-_z) * (Y-_y); A[2][2] += (Z-_z) * (Z-_z); } MatrixXd C(3,3); C <<A[0][0]/k, A[0][1]/k, A[0][2]/k, A[1][0]/k, A[1][1]/k, A[1][2]/k, A[2][0]/k, A[2][1]/k, A[2][2]/k; #pragma endregion EigenSolver<MatrixXd> es(C); MatrixXd Eval = es.eigenvalues().real().asDiagonal(); MatrixXd Evec = es.eigenvectors().real(); MatrixXd u,v,n; double a = Eval.row(0).col(0).value(); double b = Eval.row(1).col(1).value(); double c = Eval.row(2).col(2).value(); #pragma region SET U V N if(a>b && a>c) { u = Evec.row(0); if(b>c) { v = Eval.row(1); n = Eval.row(2);} else { v = Eval.row(2); n = Eval.row(1);} } else if(b>a && b>c) { u = Evec.row(1); if(a>c) { v = Eval.row(0); n = Eval.row(2);} else { v = Eval.row(2); n = Eval.row(0);} } else { u = Eval.row(2); if(a>b) { v = Eval.row(0); n = Eval.row(1);} else { v = Eval.row(1); n = Eval.row(0);} } #pragma endregion MatrixXd O(3,3); O <<u, v, n; MatrixXd UV(k,3); VectorXd N(k,1); for( int i=0; i<k; i++) { double x = dataPts[nnIdx[i]][0];; double y = dataPts[nnIdx[i]][1];; double z = dataPts[nnIdx[i]][2];; MatrixXd X(3,1); X << x-_x, y-_y, z-_z; MatrixXd T = O * X; double ui = T.row(0).col(0).value(); double vi = T.row(1).col(0).value(); double ni = T.row(2).col(0).value(); UV.row(i) << ui * ui, ui * vi, vi * vi; N.row(i) << ni; } Vector3d S = UV.colPivHouseholderQr().solve(N); MatrixXd II(2,2); II << S.row(0).value(), S.row(1).value(), S.row(1).value(), S.row(2).value(); EigenSolver<MatrixXd> es2(II); MatrixXd Eval2 = es2.eigenvalues().real().asDiagonal(); MatrixXd Evec2 = es2.eigenvectors().real(); double kmin, kmax; if(Eval2.row(0).col(0).value() < Eval2.row(1).col(1).value()) { kmin = Eval2.row(0).col(0).value(); kmax = Eval2.row(1).col(1).value(); } else { kmax = Eval2.row(0).col(0).value(); kmin = Eval2.row(1).col(1).value(); } double thresh = 0.0020078; if (kmin < thresh && kmax > thresh ) cout << x << " " << y << " " << z << " " << 255 << " " << 0 << " " << 0 << endl; else cout << x << " " << y << " " << z << " " << 255 << " " << 255 << " " << 255 << endl; } delete [] nnIdx; delete [] dists; delete kdTree; annClose(); } Thanks, NISHA…
mers considering extreme sports reject mainstream retailers and like to check out small stores rather of at chains plus malls. Several smaller retailers discuss trends in sports shoe sales. http://skateszone.com/
Though athletic shoes and sports stores and from doorways retailers have reported somewhat uptick in footwear sales due to the increase in extreme sports, the particular beneficiaries inside the trend are independent surf and skate niche stores.
Some West Coast surf and skate shops stated teenagers and even more youthful Generation Xers are not only rejecting traditional sports, but they're also shunning mainstream retailers and malls meant for smaller niche shops transporting hard-to-come-by brands.
Eddie Miyoshi, district manager at Atomic Garage, a 3-store chain situated in Gardena, Calif., stated the soaring recognition of skateboard footwear has boosted the retailer's total footwear business 20-thirty percent this year, rather of '95.
Skate footwear presently represent 80-90 % of Atomic Garage's shoe sales, while couple of years back, Dr. Martens and Timberland drove the retailer's footwear business.
Like many retailers, Miyoshi pointed to Airwalk since the trend's catalyst.
However, if Airwalk broadened its distribution to larger chains, which are frequently located in malls, only a few skate shoe customers adopted. Rather, many youthful males have switched for your skate shops for additional elusive brands like Etnies, Duffs, and Electricity Footwear by Circus. By refusing to market bigger retailers or sports stores, these brands are increasing their cachet among youthful consumers.
"Kids don't want stuff which have been within the shops,In . Miyoshi added.
Searching ahead, Miyoshi forecasted skate shoe sales will remain strong through spring '97 provided "the [hot] vendors don't auction other [non-particularly shop] retailers."
"Skaters and non-skaters are rebelling against mainstream retailers so on to surf and skate shops for many looks," echoed Mark Richards, co-online sources Val Surf, a 3-store chain situated in North Hollywood, Calif. Soaring sales of skate footwear have driven total footwear receipts up 25 percent this year rather of '95.
"The quantity of that increase might be connected while using exposure of maximum games? I am unsure. [Skate footwear] may also be actually the think about the moment,In . Richards acknowledged. And in relation to getting this right look, youthful customers can be very picky.
"Skateboard footwear is a huge category for people, but we're not able to own the brands, Etnies, Duffs, Electricity and Nice, simply because they won't sell us," stated Mark Anderson, buyer at Chick's Sports, a six-store chain in Covina, Calif. "We have people coming every single day requesting them." Consequently, skate footwear have consistently ongoing to obtain about 5 % of Chick's overall footwear business. http://skateszone.com/the-top-8-best-skateboards-for-beginners-reviews-2017/
Nonetheless, some outdoors, niche sports and sports retailers are noting the growing recognition and coverage of maximum sports will receive a modest impact on footwear sales. Trailrunning footwear and approach/outdoors crosstrainers will be the two groups benefiting the very best inside the recognition. Like the skate shoe business, some retailers realize that styling instead of function frequently drives sales of individuals footwear.
"At this time the merchandise is a lot more visual than function," stated Chet James, gm of Super Jock 'N Jill, Dallas, speaking about trailrunning footwear. Still, James noted the current hype over adventure sports helps draw more customer traffic. "The marketing campaigns and media help bring growing figures of people in, nonetheless they frequently occasions day an issue that increases results on their own account,Inch he conceded.
John Wilkinson, executive vp inside the 85-store chain Track 'N Trail, Eldorado Hillsides, Calif., stated the shop has "seen some activity in approach footwear," but he requested the amount of consumers depend in it commercially sport. And, instead of accelerating total footwear business, Wilkinson speculated elevated sales of approach footwear and trailrunners are gnawing away at traditional hiking shoe and boot volume.
But Dan Bazinet, president of Overland Exchanging, a 34-store chain situated in Westford, Mass., believes the company-new looks have breathed existence for the wilting hiking boot category. "[Approach-type footwear] don't represent the lion's participate the hiking market, nonetheless they have elevated the hiking business and provided us extra sales," Bazinet stated.
He designated Timberland's Treeline Series and Rockport's Leadville line as strong performers. Unsurprisingly, he noted the company-new looks are attractive to youthful consumer base than traditional hikers.
For that month of June, sales of men's hikers were up 49 percent at Overland, rather of June '95, while sales of women's hikers were up 17 % for that month. Bazinet also attributed elevated sales that shops walked inside the hiking business, departing that business for that specialists.
Some retailers draw a good example concerning the hiking boom of two yrs ago combined with the current extreme sport phenomenon. "Plenty of bigger chains will get a specific percent in the industry while [extreme] sports remain a fad because they are selling cost-point type gear," described Steven Carre, assistant hard goods buyer at Adventure 16, a six-store chain situated in Hillcrest.
"However individuals [true enthusiasts] will say `we need real gear' and may shown up at us. That will help us after a while. What Size Skateboard good for an 3 4 5 6 7 8 9 10 11 12 13 14 year old
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