8-Tree waveCHECK Makes Blade Wrinkle Detection Simple

In this Uptime Spotlight, Erik Klaas and Johannes Leib from 8-Tree
discuss their waveCHECK system, which detects and measures surface
defects on wind turbine blades. The system uses 3D optical scanning
technology to identify wrinkles and other issues with high
precision, helping improve quality control in blade manufacturing
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YouTube channel here. Have a question we can answer on the
show? Email us! Allen Hall: Welcome to the Uptime Wind Energy
Podcast Spotlight. I'm your host, Allen Hall, along with my co
host, Joel Saxum. Today, we're diving into revolutionary blade
inspection technology from 8-Tree. 8-Tree's WaveCheck system uses
3D optical scanning and augmented reality to detect and measure
surface defects on wind turned blades with unprecedented precision.
Joining us is Erik Klaas, the co founder and CTO of 8-Tree, and
Johannes Leib, a program manager with 8-Tree, who brings over 15
years of wind blade industry experience, specializing in composites
and fiber reinforced plastics. Joel Saxum: Welcome to Uptime
Spotlight, shining light on wind energy's brightest innovators.
This is the Progress Powering Tomorrow. Allen Hall: Erik and
Johannes, welcome to the show. Erik Klaas: We are glad to be on
your podcast. Allen Hall: I'm excited to talk to both of you
because I've seen your technology on YouTube quite a bit and now on
LinkedIn and it's quite impressive. And I want to start by asking
really, how are you trying to handle wrinkles? It seems like
wrinkles are a huge problem in the wind industry. They're hard to
detect and we're getting escapes out of the factory. You want to
discuss how big of an issue wrinkles are. And Blades is at the
moment. Erik Klaas: Yeah, most likely this is a good topic for
Johannes to speak about for one hour. But as I got into this
business late, maybe I get to give you my perspective. So when I
got into the wind business first, our legacy is in aerospace. So I
saw a wrinkle and I never thought it could be such a problem or
lead to catastrophic results. What is a wrinkle? I happen to have a
separate part here. Which is a mock up that we did. We do this for
testing our system. A wrinkle basically is a deviation in the glass
fiber layup of a turbine blade. And it's very small, so you can't
even almost not see it. But it can lead to the blade cracking in
these particular areas where the wrinkle happens. And therefore,
the inspector's task is to measure how wide and how high is a
wrinkle. And so the ratio between width and height is what they
then calculate, and there's a limit to that ratio. And that is what
an inspector has to do. And currently, they are doing it with hand
tools. And a hand tool is a Dial gauge or it can be what they call
a comp gauge. So they push it on the surface so they get the
contour of this wrinkle and then with that contour they measure
actually the width and the height of it. Allen Hall: It can be very
difficult to detect some of these wrinkles because the laminates in
these longer blades, the laminate is very thick. So if you have a
wrinkle somewhere in the middle of this laminate, the surface
Defect or the surface curvature change is minuscule, right? Erik
Klaas: It is. And there is a limitation of our technology that I
need to speak about. So we can only detect and measure those which
are on the top layer. So if they go through the whole layup of
layers and they are visible on the surface, we can measure them.
And if they only appear in deeper layers, we can't. So you need
like NDT measures, methods that go to deeper layers to inspect
those. But most often also the layer the wrinkles in deeper layers
are visible than on the top surface. Joel Saxum: So you need that
physical deviation on the top. If you ran your hand over it, you'd
be able to feel it. And that's what you guys need to be able to
have to sense it. Okay. Erik Klaas: Yes. What we are doing Joel
Saxum: so our Erik Klaas: measurement technology is a surface
inspection technology. So it always measures deviations on the
surface. Correct. Allen Hall: So as part of blade inspections,
ideally those wrinkles are getting measured for length and width
and all of them in which there can be a number of them on any blade
because wrinkles are not uncommon. It's the question of, are they
serious enough to be repaired? I think the question then becomes
how sensitive is your equipment to do this? Because we seem to have
a lot of blades out in service that do have wrinkles. I've seen
them. Yeah. Over the summertime, I saw a number of them. It's hard
sometimes to detect the wrinkles. It is not necessarily obvious to
an inspector that the wrinkle that exit may exist there or how
critical that is, but the sensitivity of your equipment is quite
impressive. You want to describe how sensitive it is to small
perturbations on the surface? Erik Klaas: Yeah. So what we use, the
technology is, it's called structured light scanning and how it
works. It projects a pattern on the surface and from a different
angles. Those patterns are observed from a camera, a digital
camera, and as there's an angle in between, so when the surface
changes, also the shape of these patterns changes, and that's how
is, how we get access to the third dimension in these measurements.
And so what's good for us, that technology has developed over the
last 20 years quite significantly and it's not a to go into the
micron level of detail. surface deviations. And I mentioned, so our
background is aviation industry. So we, with the same technology,
we measured dents and bumps on the outer skin of aircrafts. And so
there are our measurement uncertainties in the magnitude of 50
microns, or those People that prefer inches, so that is two
thousandths of an inch yeah, 50 microns. Accuracy in the wind power
industry, or on surfaces like glass laminates, is a bit worse.
Because the surfaces are difficult to measure. They are a bit
transparent, they are a bit rough. Yeah, it's, in the best case, 50
micron. Joel Saxum: Yeah, I think anybody that's been inside of a
blade can attest to at least one defect in every blade, right? If
you're in there looking around, you see something, whether it's a,
extra glue here, or some dry glass here, or a little bit of D lam
here, and it, one of the difficult things from, from an untrained
eye, I've been in a lot of them supporting people. is knowing
what's actually an issue, right? Because you'd look and be like,
oh, is that a problem? Is that going to affect structural
integrity? Maybe not. Maybe this one will. And that takes
expertise. But what you guys have created is a tool to help these
experts. And so what I want to talk about is then, The ability to
scan, cause a lot of times we're talking inside of the blade,
right? Cause we're looking, cause the outsides gel coat, it's all
cleaned up. Everything looks pretty. So everything's been sanded
and smooth. But if you're inside the blade to get that 50 micron
accuracy, Okay. So in my mind, I'm always thinking geometry, there
has to be a certain distance to be able to look at that angle. How
big is this tool? So how far can these experts get in the blade
with it to be able to look at things? Erik Klaas: Yeah, good
question. And so of course also the tool has evolved over time. So
in the background we see actually two versions. There's one over
there. I hope that's visible in the image. So that tool has a
standoff of about 50 centimeters. The weight is about four
kilograms, four and a half kilograms. It's all self contained. So
it's battery powered, so there's not an additional computer. It's
all within that unit. And. Yeah, you can go pretty far into a blade
to use it until your space is limited to this about maybe 70
centimeters. So that's the space you need in front of the surface.
Joel Saxum: And anything I mean, 70 centimeters is, so if you're
getting down to basically, with someone operating at like a meter
of a chamber or so, most all of the defects that need to be dealt
with are going to be from there back towards the root anyways.
Because that's going to be the high structural loading zone. That's
where, if you're going to develop a crack or something, those are
the ones that you really need to see. Can you tell us about some
use cases in the field or where this thing's being used right now?
Erik Klaas: So yeah, we mentioned wrinkle measurements and wrinkles
in and maybe that's a better question for Johannes to answer
because how blades are made, I think is that there's different
opportunities and as these butterfly blades, where they make them
out of two shells. And glue them together afterwards. There it's
not a problem to access the entire inside of the blade. So to the
very tip of the blade. But what are the other technologies,
Johannes, that used to make Johannes Georg Leib: Currently, our
tool is mainly used in the manufacturing because that's where we
started developing it with some of the big global blade
manufacturers. But we are also looking into applications in the
field because the, yeah. The functionality of the tool is just the
same in the field as it would be in the factory. In the factory, we
are now also going towards automatization. That it's not a handheld
tool anymore, but we're doing some research on having it automated
on either a robot or yeah. a portal stuff. Basically the technology
works everywhere because it's independent from any infrastructure,
you can take it anywhere. It's a,