Petrol Engine RPM Counting Using mike and Engine Sound Input ?

Projects General Guidance
1

Dear Sir,

I need to count petrol engine RPM using engine sound as a part of my college project. I got following information; Arduino based RPM counting. But it is based on pick up from ignition coil. I need to do it using engine knock sound.

Arduino Car or Motor Bike Engine RPM Meter>> Index of /rpmsparkplug

So please give me any link or information on this kind of project. Is it possible to count number of engine piston knocks using engine sound and feeding that mike analog input to arduino and count rpm ?

I must be thankful to you if you will kindly reply soon.

Thanks.

2

I'd use accelerometer or piezo knock sensor. Filtering may be great part of the project, but they manage to measure heartbeat by uCPU, so on-line resources on topic could be good jump-start point.

3

Abkad:
Is it possible to count number of engine piston knocks using engine sound and feeding that mike analog input to arduino and count rpm ?

The term 'knock' has a special meaning in the context of engines and might not be what you mean here. Is this intended for a diesel engine, or petrol?

If you are trying to get a rough gauge of the engine speed from the sounds it makes then I suspect that monitoring sound at the exhaust would be your best bet. You would need to do frequency analysis to determine the frequencies present and then figure out how to recognise the characteristic frequency corresponding to the interval between cylinder ignition events.

The approach you seem to be heading down with your references to 'knock' is monitoring noise within the engine block. I suggest you make/borrow a set of det cans so that you can get some idea of what the noise sounds like before you make any serious attempt to pursue that approach - I think you will find there is a huge amount of noise and even picking out a genuine knock (preignition) event, which sounds as if somebody has struck the engine with a hammer, can be difficult in that environment. If it's a petrol engine then I expect you'll find there is no meaningful signal there in the first place. If it's a diesel you may be able to detect the ignition events but I suspect it would be difficult or impossible to get any reliable reading.