The fabric is the sensor: How structure can shape wearable tech

When designing a wearable sensor, we obsess over circuits and signal processing — but what if the biggest performance shift comes from something as simple as fabric structure?  I can already sense some of you raising an eyebrow at your screen, but bear with me for a moment. Those of us who develop wearable technology — whether it’s a pressure-sensing insole or a posture-monitoring shirt — have probably all run into the same roadblocks: inconsistent sensor data, uncomfortable wear, or fragile materials that fall apart after a few washes. I know I certainly have.

Constantly facing these issues as a textile science researcher back in grad school, I started questioning why we so often default to non-textile materials for e-textile components in the first place.

I come from a background in soft goods engineering, where we deal with all the textile-y, squishy, stretchy parts of wearable products — the things that make them actually wearable. But I’ve also spent a lot of time in sensor development environments, and I kept noticing this disconnect. We treated fabric like packaging. At best, like a mounting surface. Not like something that could actually influence sensor behavior.

So I decided to test that — and like any good grad student, I lost a bit of my sanity along the way.

What happens when you use fabric as the sensor’s dielectric?

Capacitive pressure sensors are pretty common in wearables. They work by placing a compressible dielectric material (a nonconductive insulator, like silicone or foam) between two conductive layers. When the material compresses, the plates get closer together, and the sensor’s capacitance increases. That change in capacitance is what gets translated into data.

Diagram of sensor setup. Figure not drawn to scale.

This dielectric layer plays a big role in how the sensor behaves — and engineers often manipulate its structure (like adding micropores to silicone) to improve sensitivity, range, or linearity.

That’s what sparked the experiment. I knew that engineers often modify silicone dielectrics by adding micropores to increase porosity and improve sensor sensitivity or range. And I thought, well, fabric structure also affects porosity. So why can’t we just use that instead?

That’s what I did in this study. I tested 12 different synthetic fabrics — all pretty standard in apparel — and measured how they behaved when used as the dielectric layer in a basic parallel plate capacitive sensor. I controlled for fiber content and thickness to isolate how structure alone affected performance. And the results were honestly more dramatic than I expected.

Diagram of discharge process.

Diagram of weight application.

What I found

The idea going in was pretty simple: If fabric structure affects how a material compresses — and engineers already tweak structure in silicone to adjust sensor output — then it should also affect a textile’s performance as a dielectric.

And it turns out that it does. A lot.

I grouped the 12 fabrics by fiber type and thickness and used each one as the dielectric in a controlled capacitive pressure sensor setup. I measured:

• Sensitivity: How much the capacitance changed with pressure
• Linearity: How smooth and predictable the response curve was
• Repeatability: How consistent it was across trials
• Hysteresis: Whether the response looked different going up versus coming back down

What surprised me was how differently some of the fabrics performed — even when they looked nearly identical on paper. Two polyester fabrics with the same fiber content and nearly identical thickness showed noticeably different sensitivity — likely due to subtle differences in structure or finish. And in one case, I tested two acrylic fabrics that appeared to be the exact same product, just from different bolts — and they still performed differently. One (fabric 2) was more sensitive and more consistent than the other (fabric 3).  

Hysteresis error for fabrics in Group 4.

Sensitivity for fabrics in Group 4. Fabrics 2 and 3 are the same fabrics from different bolts.

Sensitivity of fabrics in Group 1.

Sensitivity of fabrics in Group 3.

That kind of variation matters. If fabrics that appear identical don’t behave identically, it introduces a design consideration: material consistency. To use fabric as a dielectric in a reliable sensor, you may need tighter sourcing control, calibration across units, or tolerance built into your signal interpretation.

I initially assumed air permeability might explain these differences. More breathable = more compressible = more sensitive, right? But that didn’t hold up. Fabrics with similar air permeability often had very different output profiles. Porosity, on the other hand — calculated using bulk density and fiber density — showed stronger correlations. 

In general, higher porosity fabrics were more sensitive at low pressures, but also more prone to hysteresis and less repeatable. Denser fabrics offered more consistent output, but at the cost of sensitivity. The correlations weren’t perfect, but they were meaningful — and far more predictive than air permeability alone.

In short: Fabric structure mattered. And not just for comfort or durability — it directly shaped how the sensor behaved.

Why this changes the game for wearable tech

If fabric structure can influence sensor behavior as much as my study suggests, then it’s not just a comfort layer — it’s a design tool. That opens up a lot of new possibilities for teams working in wearables, especially those trying to move fast or scale production.

First, there’s the cost and speed factor. Reworking a circuit or rewriting firmware to fix signal issues can be time-consuming and expensive. If some of that tuning can happen earlier — just by changing the fabric — that’s a fast, low-cost lever for prototyping and iteration. It doesn’t replace good circuit design, but it gives you another tool before diving into a hardware redesign.

Then there’s integration and durability. Unlike many custom sensor materials, fabrics are already designed for stretch, moisture management, and laundering. You don’t have to invent ways to make them skin-friendly or breathable — they already are. That said, fabric structure does change with wear and washing, and we’d need further research to understand how those changes affect sensor performance over time. Still, the ability to work with existing textiles — and possibly skip lamination, encapsulation, or adhesive bonding — is a big step toward simpler, more scalable smart garments.

And maybe most importantly, there’s user comfort. A sensor that actually feels good to wear is more likely to be adopted. If you can hit your performance targets using materials already familiar to your cut-and-sew team? That’s not just good engineering — that’s smart product design.

Beyond design flexibility, this also impacts how we manufacture and validate wearable tech. If bolt-to-bolt variation changes sensor output, that could affect everything from device calibration to machine-learning model accuracy. A posture-monitoring shirt made from one batch of fabric might behave differently from another — and if that difference isn’t caught, it could throw off user feedback, trigger false alerts, or invalidate data over time.

This kind of variability doesn’t make fabric a bad material — it just makes it a real one — one with constraints, trade-offs, and opportunities, just like any engineered component. And that’s exactly why it needs to be part of the design conversation from the start.

Why soft goods engineers need a seat at the table

This all points to something I care about deeply: Soft goods engineers need to be in the room early. Too often, we’re brought in at the end — to “make it wearable” after the electronics are finalized. But as this research shows, fabric isn’t just packaging; it’s part of the system.

If fabric structure can shift sensitivity, linearity, and repeatability, then those early design decisions aren’t just aesthetic — they’re functional. Ignoring them until the last minute means missing a chance to tune performance from the start.

Soft goods engineers bring critical insight into how materials behave under pressure, stretch, and wear. We understand how fabrics interact with bodies and sensors — and bridging that gap is key to creating smart garments that actually work outside the lab.

Conclusion

This research started with a simple question: What if we treated fabric like a real part of the sensor system?

The answer turned out to be more impactful than I expected. Fabric structure shaped sensor output — sometimes dramatically — even when everything else stayed constant. It showed that material choice isn’t just about comfort or aesthetics. It’s about signal fidelity, manufacturing strategy, and long-term usability.

If you’re working on wearable tech, consider this your invitation: Bring your soft goods team in early. We don’t just make things wearable. We help make them work.

Shimra Fine is a soft goods engineer, informal member, and founder of Fine Soft Goods Consulting, with nearly two decades of experience in textile design, wearable technology, and human-centered prototyping. With a BFA in Costume Design from SCAD and an MS in Textile Science from the University of Rhode Island, Shimra brings deep expertise in both the form and function of soft goods—especially in complex, sensor-integrated applications.

informal is a freelance collective for the most talented independent professionals in hardware and hardtech. Whether you’re looking for a single contractor, a full-time employee, or an entire team of professionals to work on everything from product development to go-to-market, informal has the perfect collection of people for the job.