Video compilation of some of the performed tests: https://vimeo.com/171714619 Recently, architects and researchers on digital fabrication methods have been exploring the interaction between form, production process and material. This thesis investigates how the robotic single point incremental forming of sheet metal can make a useful contribution in transforming metal facade cassettes, by both focusing on its strengthening capacities and its ability to fabricate elements with a customized aesthetic. Through several brief studies, alternative process planning methods are explored and evaluated on their structural and architectural implications. Additionally the potential of reinforcing facade panels is investigated through simulation and tested during a depressurization test, simulating a wind load. This research shows how modifying the geometry of the cassettes enhances their structural performance. When achieving high degrees of accuracy is not the main concern, alternative process planning methods have shown to be promising for both decreasing the production time and increasing the rigidity of the formed part. The flexibility of such a robotic process enabled an explorative approach of manufacturing, resulting in an otherwise unachievable aesthetic. While considering the structural, aesthetic and economic aspects, this research aimed to set a general framework for further investigation, in order to ultimately introduce single point incrementally formed facade cassettes in common architectural practice.

1. Strengthening and customization
of zinc facade panels using
single point incremental forming
Gert-Willem Van Gompel
Master in Engineering: Architecture
KU Leuven
Department of Architecture
Department of Mechanical Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

2. Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion
Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Introduction
Title:
Strengthening and customization
of zinc facade panels
using single point incremental forming (SPIF)
Research question:
This thesis investigates how SPIF can make a useful contribution
in transforming metal façade cassettes, by exploring
its strengthening capacities simultaneously with
its ability to fabricate elements with a customized aesthetic.
How?
Literature - context
digital fabrication
SPIF
Investigation of
the toolpath generation
the form finding hypothesis
Fabrication with SPIF
Verification with depressurization tests

3. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

Digital fabrication as a “missing link“ between design (left) and production (right).
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

4. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

http://www.digitaltrends.com/computing/best-desktop-3d-printers/
3D Printing as an example of digital fabrication.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

5. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

http://gramaziokohler.arch.ethz.ch/web/e/lehre/276.html
“Remote material deposition”, different approach of digital fabrication.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

6. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

computerization
computation
Instead of exactly translating a virtual model into reality, one can design through
production. This can also be seen as the difference between computerisation and
(material) computation.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

7. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre

Two classification methods of existing
digital production techniques. In
the horizontal direction a technical
distinction can be found (Hauschild
& Karzel 2011), while the vertical
separation represents a more
fundamental theoretical difference.
(Gramazio & Kohler 2014). The
question mark in the table is where
the scope of this thesis is situated.
AddingSubtractingJoiningTransforming
Result determined by
- Virtual model - Virtual model / toolpath
- Production technique
- Material
Fig. 5 Top DSIF Method A with a forming tool and a support tool. Bottom DSIF Method B with
two forming tools
40 A. Kalo and M. J. Newsum
?
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

8. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
SPIF
SPIF = Single Point Incremental Forming
• sheet metal processing technique
• without die
• small batches & prototypes
• relatively cheap & fast
Fig. 5 Top DSIF Method A with a forming tool and a support tool. Bottom DSIF Method B with
two forming tools
Figure 17: Single Point Incremental Forming of a cone.
Figure 18: FLDo for different step sizes for AA 1050-0, with
Kim & Park [70] focused th
anisotropy on formability
measurements of the ma
carried out both along the
transverse one (TD). T
pyramid specimens with
material was the aluminium
σο = 33MPa, R0 = 0.51,
concluded that formability
greater when small diamet
the rolling direction it is larg
In order to fully understand
AISF, a simple FEM was
and Bambach et al. [69]. T
step size, ∆z, the strain in
decrease and any point is
while strains increase wi
from a stress point of
distribution is observed un
elements; in this way, th
fractures during the proces
with the sheet. Finally, at
along the wall decreases t
can be imposed without tea
Nontraditional Forming Lim
Forming limit diagrams us
shown as FLC in conve
However, extensive resea
much higher strains ach
Forming Limit Curve (FLC
as shown in Figure 20 [32
forming strains [32] were a
AA 1050-0 sheet used in th
with a grid causing stre
premature failure to occur.
Young and Jeswiet [62]
develop a composite FLD
They used five different s
convex and concave curve
cone, a hyperbola, a py
compressive and tensile st
UUppppeerr lliimmiitt
LLoowweerr lliimmiitt
Εmax, FLDo
3.5
Depth of step, ∆z, mm
0.5
1.5
2.5
0
1
2
3
0.00 1.00 2.00 3.00 4.00
points to generate new, virtual target geometry. This virtual
part geometry forms the basis for the determination of an
improved toolpath. Using a scale factor of 0.7 was found
to provide optimal results for part made of DC04, 1.5 mm.
V shaped
tub
Ambrogio et al. [106] use an in-process measurement
system that allows the determination of deviation between
the anticipated intermediate part geometry and the actually
realized intermediate shape. Per layer (incremental
toolpath contour) the observed deviations are measured to
correct the toolpath geometry for the next contour.
ConeCross Hexagon
The proposed system has been tested with a discrete point
contact measurement system, used interactively, thus
simulating the availability of real in-process measurement
equipment. The toolpath optimization algorithm has been
tested with pyramid part geometry. The author claims
significant accuracy improvements. No quantitative output
is however available to evaluate the achievable
dimensional accuracy.
HyperbolaDome
5 lobe
shape
5 EXAMPLES OF APPLICATIONS
The major advantage of asymmetric incremental forming is
it can be used to make asymmetric parts, quickly and
economically, without using expensive dies. Shapes used
to demonstrate the abilities of the process are shown in
Table 8. Some of the shapes illustrated have been used to
conduct springback experiments, and in determining the
maximum draw angle φ, others are just for demonstration
of process abilities.
The asymmetric single and two point incremental forming
processes are still in their infancy. Much research work
remains to be done and to do this appropriate shapes are
needed to develop: FLD’s, springback models and models
to test accuracy. Standard shapes are used to determine
what the draw angles should be for different materials and
thickness. Standard shapes are needed to compare
experimental results and for testing the process for
maximum speeds of deformation.
When testing materials for the maximum draw angle φ a
truncated cone as shown in Figure 15 was agreed upon
[59]. This shape has also been used by others [31, 32, 33,
59, 64, 66]. A pyramid shape has also been used on many
occasions to demonstrate the asymmetric abilities of the
new process plus it has become useful in determining the
springback that occurs for different material thickness’ and
for conducting pre and post process material tests [59, 64,
65, 67, 77]. Jadhav [100] has also used the pyramid to
conduct studies of twisting in a shape once forming is
completed.
There is not agreement on which shape or shapes should
be used to develop FLD’s for the new processes. Filice
[32] and Hirt [78] have used a pyramid. Young is a
proponent of using several shapes each of which has
elements contained in most part shapes [62].
5.1 Rapid Prototype Examples
Making Rapid Prototypes, with sheet metal as the base
material, giving a part that can be used directly in the
Table 8: Shapes used to demonstrate the viability of the
process and for experiments.
oven cavity for use in developing country applications. The
last two are for the same manufacturer of custom
motorbikes; the first part is for a motorbike seat and the
second is part of a gas tank.
5.2 Custom manufacture of a solar oven
The SPIF process has made it possible to manufacture an
aluminum solar oven cavity, economically without dies.
The ability to make a sheet metal cavity, inexpensively,
has allowed designers of the solar oven to redesign other
parts of a product, thereby reducing the cost and labour in
making a solar oven. A solar oven has been designed for
export to developing countries. Originally the oven cavity
was made from fibreglass, and painted black. The major
drawback, was the fibreglass wall was 7 mm thick, heavy,
time consuming to build, and labour intensive. The
possibility of using dies to form sheet metal into solar
cooking cavities was investigated and found to be very
expensive. This lead to considering SPIF of sheet metal as
a method of manufacture. Figure 49 shows how the
assembled solar oven works. The red shape is the part
which is formed by SPIF. A three dimensional model was
made in a Unigraphics environment and Figure 50 shows
the model and increment details. The total depth of the
model is 74 mm. The downward step for each pass was
set up differently for the two sections shown; ∆z = 0.4 mm
from A to B, and ∆z =0.3 mm from B to C.
The method of programming included a z-level profile
following part contour, which is available in Unigraphics,
was used.
Details of the process set-up in Unigraphics are:
Truncated pyramid
Faceted
cone
Multi-shaped surface
Kalo, A., & Newsum, M. J. (2014). An Investigation of Robotic Incremental Sheet Metal Forming as a
Method for Prototyping Parametric Architectural Skins. Robotic Fabrication in Architecture, Art and Design
2014, 33-49.
Jeswiet, J., Micari, F., Hirt, G., Bramley, A., Duflou, J., & Allwood, J. (2005).
Asymmetric single point incremental forming of sheet metal. Cirp Annals-Manu-
facturing Technology, 54(2), 623-649.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

9. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
SPIF
overall geometry curvature. The parts were spot welded together at the valleys and
peaks to create the self-supporting system (Fig. 8).
Another system was developed as a series of panels that have a global pattern of
ribs which structure the edge and register the panels through overlapping con-
nections. The central protrusions are formed as undercuts (easily achievable with
multi-axis forming) and orient the panel on a clipping system (Fig. 9). The
bespoke ribs, bumps, and surface textures aren’t formed solely on their aesthetic
value, but are born out of the conflation of design, fabrication process, and con-
nection detailing. In addition, they deliver a performative relationship between the
panels and the materials formed (Hensel and Menges 2009). The aim is to avoid
Fig. 8 Aggregation of self-supporting thickened porous skin
An Investigation of Robotic Incremental Sheet Metal Forming 43
Kalo, A., & Newsum, M. J. (2014). An Investigation of Robotic Incremental Sheet Metal Forming as a Method for Prototyping Parametric Architectural Skins. Robotic
Fabrication in Architecture, Art and Design 2014, 33-49.
Bailly, D., Bambach, M., Hirt, G., Pofahl, T., Della Puppa, G., & Trautz, M. (2015). Flexible manufacturing of double-curved sheet metal panels for the realization of
self-supporting freeform structures. Key Engineering Materials, 639, 41-48.
Nicholas, P., Stasiuk, D., Nørgaard, E. C., Hutchinson, C., & Ramsgaard Thomsen, M. (2015). A
Multiscale Adaptive Mesh Refinement Approach to Architectured Steel Specification in the Design of
a Frameless Stressed Skin Structure. Modelling Behaviour, 17-34.
Architectural applications with assymetric incremental sheet forming.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

10. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 1: Toolpath generation
Left: Contours with
continuous step-down.
Right: Contours with more
continuous on-surface
distance.
Left: Contour toolpath with
abrupt transition.
Right: Spiral toolpath.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

11. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
Formation of the line pattern. Left: regular spiral toolpath with
circles and interpolation points. Right: Pattern toolpath by
interpolating between points on circles.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

12. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
Six variations of toolpath patterns.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

13. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
Robot setup.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

14. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
Six variations of toolpath patterns produced with SPIF.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

15. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
Six variations of toolpath patterns produced with SPIF.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

16. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 2: Toolpath patterns
0 50 100 150 200
0,0
0,5
1,0
1,5
2,0
Toolpath length (m)
Springback(mm)
2
13
5
6
4
1
2
3
4
5
6
Smaller step-down toolpaths (5 and 6) showed a higher springback value.
The curled toolpath with a step-down of 3 mm (4) resulted in the lowest springback,
while still reducing the toolpath length compared to the small step-down toolpaths.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

17. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 3: Direct programming
8
1
2
3
4
57
6
Top and side view of the X-type toolpath. In
the top view the locations of the first eight
interpolation coordinates are illustrated.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

18. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 3: Direct programming
Photographs from an X-type variant produced with SPIF on a sheet of zinc.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

19. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 3: Direct programming
AddingSubtractingJoiningTransforming
Result determined by
- Virtual model - Virtual model / toolpath
- Production technique
- Material
Fig. 5 Top DSIF Method A with a forming tool and a support tool. Bottom DSIF Method B with
two forming tools
40 A. Kalo and M. J. Newsum
Fundamentally different approach
of incremental sheet forming,
corresponding with the ideas of
direct programming and material
computation.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

20. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 3: Direct programming
Rendering of a project
design from the architectural
office DMOA, served as
the conceptual idea for the
Square-type toolpath.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

21. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 3: Direct programming
1 2
34
5 6
78
910
11 12
1314
15 16
17
18 19
2021
22 23
24 25
2627
28 29
3031
Top and side view of the Square-type toolpath and cassette. In the top view the locations of
the first 31 coordinates are illustrated.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

22. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 4: Form finding - simulated
0,04% (b)
0,31% (b)
3,67% (b)
100%
0.001% (a)
0.06% (a)
100%
a.
b.
c.
d.
e.
f.
g.
The deflection patterns of
different geometries simulated
and compared to each other.
The panels are subjected to a
virtual distributed wind load.
Shapes a,b and c are lineary
restrained at the four edges.
Shapes d - g are restrained at
the corners. From left to right:
side view - perspective view -
top view with the corresponding
deflection pattern.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

23. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 5: Form finding - measuredNom du système : Cassette Chicago QZ n° R&D : 09007 RE 023 - 2
Caractéristiques du montage ( dim. des élts, entraxe, fix. ) :
Cassette horizontale Zinc+ l = 585 mm
Fixation par Vis Ef Vis = 535 mm L = 585 mm
Profondeur 40 mm ep = 1,02 mm
Emboîtement renforcé
Vis SFS 5,5 x 37
Fixation sur 2 Profils Oméga Alu 25/10e
6 comparateurs
Déboutonnage de la vis
Forte déformation dans l'angle de la cassette
Nom des opérateurs : L. Rannou Date & Signature : 27/04/2010
J. Caron
ESSAI DEPRESSION - FICHE DE RESULTAT ( n° )
On localisera les points de mesure ( P1…P9 ), les déformations et les points de ruine
MONTAGE K7 Chicago
600
600
600
535
A (0,0)
y
Vis
P3
P2
P1
P5
P4
P6
Rails Alu
Cassette Chicago
Abstract from depressurization test report of the cassette of type
Chicago showing the alignment of the cassettes and the location of
the sensors.
Measured deformation data will be used. The data are derived from
previous depressurization tests performed by VMZINC.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

24. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Study 5: Form finding - measured
0 Pa
1500 Pa
3000 Pa
250 Pa
1750 Pa
3250 Pa
500 Pa
2000 Pa
3500 Pa
750 Pa
2250 Pa
3750 Pa
1000 Pa
2500 Pa
4000 Pa
1250 Pa
2750 Pa
4500 Pa
Graphical representation of the deformation shape after interpolation
between the measured local deflection at each stage of the test.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

25. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
First test campaign
S30 C30 C30
C30RS60
Geometry Toolpath Pattern parameters Element
Type Form Depth
(mm)
Step-
down
(mm)
Scalp
(mm)
Length
(m)
Pattern
type
Points Space
(mm)
Radius
(mm)
Spring
back
(mm)
Material Dimensions
(mm)
Thickness
(mm)
S30 FF. 30 1 10 47,7 Straight 1 / / 1,2 Zinc Natural Cassette 585 x 585 0,8
C30 FF. 30 1 35 77 Curl 3 35 25 0,4 Zinc Natural Cassette 585 x 585 0,8
S60 FF. 60 1 10 90,2 Straight 1 / / 0,9 Zinc Natural Cassette 585 x 585 0,8
R Flat 0 / / / / / / / / Zinc Natural Cassette 585 x 585 1
Cassettes of the type VMZ Mozaik transformed with SPIF, mounted
on a wall before testing.
The first test campaign consisted of the types S30, C30, S60, R.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

26. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
First test campaign
The ‘C30’ and ‘S60’ type performed the best. Additionally, none of
the ‘C30’ types did tear during the test procedure.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

27. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
First test campaign
Both the ‘S30’ (left) and ‘S60’ type (right) showed premature
damaging, which initiated the rupturing during the test.
Photographs before and after test procedure:
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

28. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Second test campaign
The second test campaign consisted of types X, Square and R (0,8 mm)
(not included in thesis text)
This test campaign lasted longer than thee previous tests. No tearing occured at the
X-type cassettes. The Square-type cassettes encountered tearing out of the screws.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

29. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Evaluation of the results
The overall impression is that the X-type performed the best at all aspects.
Note:
‘X’ and ‘Square’ types are produced on cassettes with thickness 1 mm.
‘S30’, ‘C30’ and ‘S60’ are produced on cassettes with thickness 0,8 mm.
(5)(6) (4) (3) (2) (1)
1/100
1/50
(X, Square and R08 not included in thesis text)
Pressure (Pa) at deflection of Deflection (mm) at pressure of Tearing
occurred?
Test ended
at (Pa)Type 1/100 1/50 3500 Pa 4750 Pa 5250 Pa
S30 3500 (4) / 25 / / yes (2 cassettes) 3831
C30 / / 23 / / no 3831
S60 4600 (2) / 19 33 / yes (2 cassettes) 5243
R1 2010 (5) 4600 27 38 / yes (2 cassettes) 5243
X 4850 (1) / 20 31 37 no 5588
Square 4300 (3) 5100 24 36 44 yes (1 cassette) 5588
R08 500 (6) 2500 38 / / yes 4211
Comparison of some critical values
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

30. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Evaluation of the results
Pressure (Pa) at deflection of Deflection (mm) at pressure of Tearing
occurred?
Test ended
at (Pa)Type 1/100 1/50 3500 Pa 4750 Pa 5250 Pa
S30 3500 (4) / 25 / / yes (2 cassettes) 3831
C30 / / 23 / / no 3831
S60 4600 (2) / 19 33 / yes (2 cassettes) 5243
R1 2010 (5) 4600 27 38 / yes (2 cassettes) 5243
X 4850 (1) / 20 31 37 no 5588
Square 4300 (3) 5100 24 36 44 yes (1 cassette) 5588
R08 500 (6) 2500 38 / / yes 4211
Comparison of some critical values
The overall impression is that the X-type performed the best at all aspects.
Note:
‘X’ and ‘Square’ types are produced on cassettes with thickness 1 mm.
‘S30’, ‘C30’ and ‘S60’ are produced on cassettes with thickness 0,8 mm.
1/100
1/50
(X, Square and R08 not included in thesis text)
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

31. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Conclusion
Economic
The total cost of such facade panels is influenced by
►► production time - toolpath length;
►► material usage - sheet thickness - strength;
and can be achieved by
►► modifying the geometry;
►► increasing the step-down;
►► using alternative toolpath generation methods.
1,0 1,5 2,0 2,5 3,0
0
2
4
6
8
10
12
14
16
0,0 0,5 1,0 1,5 2,0 2,5 3,0
0
20
40
60
80
100
120
140
160
Step down (mm)
Toolpathlength(m)
Step down (mm)
Toolpathlength(m)
The correlation between the
step-down and the toolpath
length (for a shallowly curved
part of 300 mm x 300 mm and
with a depth of 30 mm).
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

32. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Conclusion
Structural
Structural performance is increased by
►► applying a deeper geometry;
►► using a specific toolpath pattern (increased surface roughness).
The curled toolpath pattern showed
►► (after SPIF) lower springback values;
►► (before test) no premature damaging at the corners of the cassettes;
►► (during test) lower deformation;
►► (after test) no damage at all.
Comparison of the overall
performance of panels with
different ribbing systems
(Kalo & Newsum 2014, 45).
These superficial ribbing
systems showed to reduce the
springback after trimming.
Similar findings:
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

33. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Conclusion
Architectural
Performance-oriented design at 3 scales:
►►pattern - toolpath generation
►►form - form finding, overall geometry
►►facade
Design at each level is driven by functional or structural requirements.
Different explorations of the surface envelope of the Piraeus
tower in Athens, based on solar exposure analysis (Hensel &
Menges 2009, 1).
Performance-oriented design of a facade:
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

34. Gert-Willem Van Gompel
Master in Engineering:
Architecture (2015 - 2016)
KU Leuven
Department of Architecture
Department of Mechanical
Engineering
Promotor:
Vande Moere Andrew
Assessors:
Duflou Joost
Cannaerts Corneel
Lambaerts Marc
Mattelaer Matthias
Vanhove Hans
VMZINC:
Ecker Bruno
Lyonnet Pierre
Conclusion
One can conclude that the
►►economic,
►►structural,
►►and architectural
aspects of this topic have shown to be strongly interwoven with each other.
Future research might focus on
►►the structural influence of superficial patterning and toolpath patterns;
►►and the forming limitations of larger-step-down incremental forming;
in order to ultimately introduce SPIF in architectural practice, as an economically
feasible way of transforming metal facade cassettes. This way, every project can be
given a unique identity without any effort.
Introduction
Context
Digital Fabrication
SPIF
Studies
Study 1: Toolpath generation
Study 2: Toolpath patterns
Study 3: Direct programming
Study 4: Form finding - simulated
Study 5: Form finding - measured
Depressurization tests
First test campaign
Second test campaign
Evaluation of the results
Conclusion

35. Acknowledgments:
Department of Architecture
►► Andrew Vande Moere
►► Corneel Cannaerts
Department of Mechanical Engineering
►► Joost Duflou
►► Marc Lambaerts
►► Hans Vanhove
DMOA architects
►► Matthias Mattelaer
VMZINC
►► Bruno Ecker
►► Pierre Lyonnet