resistive fabrics tend to have an increasing resistance across distance and are great for making potentiometers and location sensors. Piezoresistive fabrics are often also resistive across distance (x,y) but have a resistance that decreases under pressure (mechanical stress) through the material (z). These materials are great for making pressure, bend and often stretch sensors. There are a range of resistive fabrics available on the market, often sold for anti-static and electromagnetic field (EMF) shielding purposes.
Here are some of our examples made using the resistive and piezoresistive properties of fabrics:
Fabric stretch sensors >> http://www.kobakant.at/DIY/?p=210
Simple pressure sensors >> http://www.kobakant.at/DIY/?p=232
Piezoresistive Fabric Touchpad >> http://www.kobakant.at/DIY/?p=3223
Squeeze sensors >> http://www.kobakant.at/DIY/?p=3175
Piezo/resistive Fabrics
One range of piezoresistive fabrics are made by coating regular fabrics in an inherently conductive polymer. These are patented processes and so far I know that Eeonyx and Panipol are two companies producing such polymers. Marktek retails EeonTex fabrics.
>> http://eeonyx.com/ (USA)
>> http://www.marktek-inc.com/eeontexconductextiles.htm (USA)
>> http://www.panipol.fi/ (Finland)
EeonTex conductive fabrics
Eeonyx is a company that has developed a propriety coating system with which they can coat almost any fabric (wovens, non-wovens, felts and knits of polyester, nylon, glass, quartz, spandex, polyolefins, and aramids) in an inherently conducting polymer (doped polypyrrole, PPY).
The coating uniformly covers the individuals fibers of the fabric, making them conductive/resistive and also black or dark gray, but the feel of the fabric itself remains pretty much the same as the coating process barely affects the strength, drape, flexibility, and porosity of the starting substrates.
EeonTex fabrics are customized for desired electrical resistance, thickness, porosity, strength, stretchability…
Depending on the base fabric, EeonTex fabrics can possess surface resistance between 10 Ohm/sq and 10 billion Ohm/sq.
Eeonyx normally only manufacture and sells its coated fabrics in minimum amounts of 100yds, but 7×10 inch (17.8×25.4 cm) samples are available free of charge and larger samples of 1 to 5 yards for a minimum fee per yard.
Non-woven fabrics for pressure sensors
Stretchy fabrics for stretch sensors
The numbers in the first image correspond with the material data in the second image.
Unknown resistive felt
Passed on to me from Eeonyx.
Anti-static Glove
A knit fabric from green/white yarn mixed with a restive thread.
>> http://www.et-esd.de/ (DE)
>> http://www.all-spec.com/1/viewitem/A205/ALLSPEC/prodinfo/w3path=cat (USA)
anti-static fabric
This fabric sold by LessEMF has resistive fibers woven into it in a diamond pattern. Unfortunately this fabric is not able replace velostat in the pressure sensors, since it is very unstable.
Unknown Black Fabric
A black woven fabric with a white non-conductive backing. It is sensitive to pressure, about 200 – 30 Ohm per cm, depending on how hard I pressure the measuring points into the fabric.
Piezo/resistive Yarn
The following stainless steel and polyester yarn also has piezo/resistive properties.
>> http://www.kobakant.at/DIY/?p=1978
Hi, can i ask if you’ve any idea to get the material, velostat? I don’t need so much of it, just a little will do. And is Linstat’s functionality similar to velostat? I’m currently looking for this material urgently, would appreciate if you get back to me asap. Thanks!
we have a separate post on velostat/linqstat: http://www.kobakant.at/DIY/?p=381
here you will find all the details!
Hi, does anyone know were I can get resistive fabric in the UK. It would be for a potentiometer? I can’t actually find any of these for sale… Thanks.
unfortunately i don’t know of an Eeontex distributor, but try emailing them for samples.
>> http://eeonyx.com/contact.php
Velostat, even though it is a plastic film, is also great for making resistive tracks for potentiometers. this website lists a UK distributor:
>> http://www.stopabductions.com/location.htm
Hi Sir or Madam
AnHui Lineo New Material CO.,LTD in China is here.
We are engaged in producing anti-static fiber,conductive fiber, anti-static gloves yarn
for anti-static fabric.
The good quality and the competitive price we have.
If you have any questions, please do not hesitate to contact with me.
Waiting for your reply.
Best Regards
Yolanda
Company: Anhui Lineo New Material CO., LTD
Tel:86-0552-2808555
Skype:yolanda_lineo
Address:WuHe county,Bangbu of Anhui Province in China
E-mail:Lineogroup1@gmail.com
Hi there, I’m trying to work with a glove that needs to let me know how much the hand is flexing. i.e. clenched fist, or open palm sort of thing. One way is to use bend sensors or just strips of resistive fabric, but in your opinion, what if the whole glove was not neoprene, but resistive fabric? Do you think there would be too much noise? I imagine the calibration would take some work, but if you’ve had any experience with it, I’d love to hear.
Thanks!
Khurram
hi khurram, i think looking to sense hand movements and gestures using a glove made of piezoresistive fabric. i have made one prototype where the inner side of the glove is resistive fabric and one the back side i sew the contact points. see more here:
>> http://theglovesproject.com/xosc-gloves/
i would love to hear your input!