Pluck detector

[prprog]

What will be the name of a circuit that will detect when a cable is touch by a finger ? The cable will have its plastic cover, so it needs to detect capacitance. Correct?

The idea is to simulate the pluck of a harp string. Yes I know there are piezo sensor, optical sensors and other type of transducers...but I want to experiment using other alternatives.

Thanks,

 

[KMoffett]

Google? capacitance proximity sensor circuit

Ken

 

[duffy]

It can detect touch, but "pluck" is different from "touch".

 

[flat5]

Wave (envelope really) shaping will be required using capacitance.
A sharp leading edge can't come from a capacitance detector.

 

[prprog]

Wave (envelope really) shaping will be required using capacitance.
A sharp leading edge can't come from a capacitance detector.

a comparator can detect a set voltage and generate a fixed predetermine behaviour to output a control voltage. Can the same be done using capacitance? set capacitance compared to a variable capacitance and once it reach a certain capacitance value output a predefine voltage?

 

[flat5]

"set capacitance compared to a variable capacitance and once it reach a certain capacitance value output a predefine voltage?"

I don't think you want to do it that way. - Harry Enfield

As suggested above, find a proximity sensor circuit.
Here is one. You need one for each string, I suppose.
Circuit - 3V CAPACITANCE PROXIMITY SWITCH - Circuits designed by David A. Johnson, P.E.

This just gives you the trigger. All the plucking for each string comes later. Sounds like a lot of plucking work to me.