hello, hopefully you guys can help me i am a bit stuck and i am sure that it is something simple i am missing.

basically i want to build a circuit with a strain gauge so that i have a pressure sensitive kill switch. the strain gauge will be used to detect pressure applied to a steal rod and activate a separate circuit which will cause a engine to cut out for 75ms once the pressure has been detected. however i am having trouble finding a way to make the strain gauge circuit in to a on/off one. as i said i am sure that it is something simple i am missing.

the strain gauge is in a wheatstone bridge and is connected to a 12v dc battery however anything apart from the strain gauge can be changed to achieve the desired result. budget is a factor though


hopefully you can understand what i am trying to explain.
thanks

 

And after the engine stops for 75 milliseconds, what? Ignore the strain gauge?

 

Use an op amp to amplify the output or use a Differential amp

amp

 

ah, thanks that is perfect i knew i had missed something simple.

unfortunately i have ran into another problem the circuit i was going to use to cut the engine (by grounding the coils) does not work. does anyone know of a circuit i can use?all i needs is a variable time of 50-100ms which can be acheaven anyway something simple like changing a capacitor would be best though


basically i am making a diy quickshifter for my motorbike (because i am a cheapskate and have more time then money ) when pressure is applied to the shift lever the engine will cut out for x amount of time allowing for much quicker gear changes there is a lot of videos on youtube if you want to have a look.

Thanks again

the bike is a sv650 btw

 

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