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I'm trying to design a circuit that would be fitted inside large plastic gloves. That when the gloves are cut the circuit produces a signal.

Currently I'm considering having a metal (probably aluminium) lining sandwiched within the gloves that would have its capacitance measured. I can do this buy simply having a tuned capcacitive touch sensor circuit kind of like this. So basically the circuit would produce high when the cut occurs. Though I don't know if this would produce the results I require.

Hoping for some possible suggestions on really how to detect when the plastic outer material is cut without using a processor as this will add overhead.

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    \$\begingroup\$ The last sentence about "without using a processor" makes the question smell wrong. You should also mention what are you going to do when you detect a breach? What are you ultimately trying to accomplish? Other than that, this is a curious design challenge. \$\endgroup\$
    – Nick Alexeev
    Commented Feb 17, 2016 at 1:28
  • \$\begingroup\$ I think I know what he's trying to do. Most likely he's building this for Fire Dept/other First Responders. They are required to change gloves if they get cut. All he wants is a logic high when there's a cut detected. He'll worry about the UI. \$\endgroup\$
    – Daniel
    Commented Feb 17, 2016 at 2:10
  • \$\begingroup\$ Sorry so at the moment I'm thinking of just using one of these chips to detect when touch occurs in a saw blade. However the circuit needs to do as little as possible since there's already 1ms delay from that chip which isn't great. As the value is going to pinged wirelessly to a processor that can deal with the data. \$\endgroup\$
    – user3510620
    Commented Feb 17, 2016 at 2:11
  • \$\begingroup\$ Errm, why does 1ms of delay matter? It's not like anybody wearing the gloves could react to or even perceive such a short delay. \$\endgroup\$
    – Tom Carpenter
    Commented Feb 17, 2016 at 2:19
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    \$\begingroup\$ I'm not sure that capacitance sensors will help. A cut to a glove is unlikely to change the capacitance by any noticeable amount - in fact putting a hand in there will affect the capacitance by orders of magnitude more. \$\endgroup\$
    – Tom Carpenter
    Commented Feb 17, 2016 at 2:24

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Have you considered TWO layers of metal in the gloves, with a layer of insulation between? Then any circuit that can detect a short should be able to detect cuts by metal objects, and also any situation where one metal layer on one side of the cut touches the other metal layer on the other side. Note, however, that this may not be reliable for cuts caused by an insulating material, such as most types of broken glass. Capacitance is no longer significant for this method.

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