Knock Detection with variable sensitivity over RPM

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dirtytorque
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Re: Knock Detection with variable sensitivity over RPM

Post by dirtytorque »

sounds interesting tps.have you got a project thread anywhere on the www?

Hoodey,when are you going to try some in car testing?
How are you going to verify that it is reading Det correctly?
I was going to use some Det cans alongside the system to verify operation.
Looks like you have thought of everything in your design.I'm impressed.
I'm only now getting back on this as all my time has been taken on modifying my engine but hofeully that is coming to an end now.
Code wise I really hadn't got very far at all.Just created an spi programming routine for the 8101 and verified its operation and that was it.
So much to do so little time...
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Guys can you fill this survey out ..It may help in giving you the product that meets your exact needs.
Black99rt
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Re: Knock Detection with variable sensitivity over RPM

Post by Black99rt »

Attached.
1999 Dakota 5.9L R/T-
MSIIe 3.1.2 Batch Fuel/MSD single coil dizzy/Stepper idle
LC-1
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Thanks guy.
Last edited by HOODEY on Sun Nov 13, 2011 8:55 am, edited 1 time in total.
Quan-Time
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Re: Knock Detection with variable sensitivity over RPM

Post by Quan-Time »

all im after is the smallest footprint possible. Not fussed about LCD, keypad, or anything. I want somethnig small i can possibly hide in my MS2 case. I use a MS2, version 3 board.
I use it on a motorbike, this is why space is my main concern.

Was any schematic finalised / usable ? What was the latest iteration which i could build ? anyone got a eagle file and parts list ? ill just end up making my own i guess.
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420aRaf
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Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

This thread is awesome, I’ve learned a lot from it. Thanks everyone.

HOODEY, Do you have a picture of your finished, finalized product?
-Rafiel
tk23
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Re: Knock Detection with variable sensitivity over RPM

Post by tk23 »

Quan-Time wrote:all im after is the smallest footprint possible. Not fussed about LCD, keypad, or anything. I want somethnig small i can possibly hide in my MS2 case. I use a MS2, version 3 board.
I use it on a motorbike, this is why space is my main concern.

Was any schematic finalised / usable ? What was the latest iteration which i could build ? anyone got a eagle file and parts list ? ill just end up making my own i guess.
http://msextra.com/forums/viewtopic.php?f=67&t=34822 - There you go. I have no idea what eagle is, but this guy has come up with a revised circuit. I would really like to see variable knock working :).
Quan-Time
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Re: Knock Detection with variable sensitivity over RPM

Post by Quan-Time »

eagle is a program which enables you to make circuits and what not. Think of it sorta like a CAD file for 3d drawing programs.. eagle files are 2d PCB layouts..

If thats the last revision, guess ill have a crack at it on a PCB. Whats the story with MS3 ? thats not having any knock detection onboard, so this will be compatible ?
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HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Dear All,








Enclosure
Last edited by HOODEY on Sun Nov 13, 2011 8:55 am, edited 2 times in total.
h22
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Re: Knock Detection with variable sensitivity over RPM

Post by h22 »

Very nice, sent you a PM. I also would like to see it as small as possible!
dirtytorque
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Re: Knock Detection with variable sensitivity over RPM

Post by dirtytorque »

why not loose the keypad and do all the programming/calabration via rs232 ?
Or maybe have a separate simple programming module??
Or indeed instead of a keypad just have selectable options via the lcd display so you won'y need a keypad??
Just thinking of ways you can save real estate.
420aRaf
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Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

dirtytorque wrote: Or indeed instead of a keypad just have selectable options via the lcd display so you won'y need a keypad??
That’s exactly what I did.

Some know my development but, I would be lying if I said I haven’t learned anything from this awesome thread. This is the second device I built from stuff i had laying around, the first one I built was fairly basic, but I’ve been doing a lot of research and experimenting with it on my car. It multi samples in TDC for knock amplitude and frequency and matches that with the data saved in the EEPROM from the user threshold windows. (7 windows, 2-8k rpm) It works very well in my car. It operates off 4 push buttons and can determine which cylinder is misfiring. (but i need to log it for best results) The warning led works well also. I’ll be silent for now as it’s in its testing stage and soon be working on a faster CPU. I’m currently working on better ways to tune knock. (Something like a self adjusting feature) It has no datalogging capabilities, but I could run a line from the serial data line to a max232 then to a laptop if needed. My ultimate goal was to do tune knock on the fly. After I figure out better ways to tune knock without an oscilloscope in my car, I will start on the SD card. Thought id share.

Image

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-Rafiel
dirtytorque
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Re: Knock Detection with variable sensitivity over RPM

Post by dirtytorque »

Great stuff.
So your system isn't communicating to MS an knock event yet?
Thats what I want to use it for so MS can then impement it's knock stratergy by retarding the timing..
420aRaf
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Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

Nope, not yet; Untested. But I do have it configured for a 5v 10ms pulse whenever there's a knock event. (if that's long enough)
-Rafiel
racingmini_mtl
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Re: Knock Detection with variable sensitivity over RPM

Post by racingmini_mtl »

You might want to put it at 20ms just to make sure it doesn't fall between 2 sampling events.

Jean
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HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

It ironic that you are gathering stuff from other people while you keep your stuff secret.
Last edited by HOODEY on Sun Nov 13, 2011 8:56 am, edited 1 time in total.
420aRaf
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Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

racingmini_mtl wrote:You might want to put it at 20ms just to make sure it doesn't fall between 2 sampling events.Jean
Thanks Jean,

I tried 20 milliseconds and 3 out of 4 times it would catch the signal and retard timing. (with .1 seconds of check time) So, I’m going to increase it to something like 50ms or 100ms? If I’m limited to .1s in tuner studio does it mean that MS will check the input every 100ms and not 10ms? If I enter values (Retard Checking Time) lower than .1 then it interprets it as 0 and I get odd results.
HOODEY wrote:It ironic that you are gathering stuff from other people while you keep your stuff secret.I will be silent as well but I am very close to product launch.Finalised the keypad nad enclosure labelling and Doing some final testing on one of the trickiest CAM and crank position sensors.The nissan distributor.
I have gathered information on how the knock senor works, but took different ways to solving the issue. Do you have verifiable proof (by scope and dyno) that your product works and reacts quickly in TDC before release? The trickiest task by far is finding TDC using PICs, and speed was an issue for me when analyzing the cam and crank inputs along with comparing user values with knock sensor input, updating LCD. In no ways am I trying to compare these devices as I’m not trying to make some cash, but I am just curious as far as the results you’ve found....
-Rafiel
racingmini_mtl
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Re: Knock Detection with variable sensitivity over RPM

Post by racingmini_mtl »

420aRaf wrote:
racingmini_mtl wrote:You might want to put it at 20ms just to make sure it doesn't fall between 2 sampling events.Jean
Thanks Jean,

I tried 20 milliseconds and 3 out of 4 times it would catch the signal and retard timing. (with .1 seconds of check time) So, I’m going to increase it to something like 50ms or 100ms? If I’m limited to .1s in tuner studio does it mean that MS will check the input every 100ms and not 10ms? If I enter values (Retard Checking Time) lower than .1 then it interprets it as 0 and I get odd results.
After writing my previous message, I realised that it was wrong because the code does update an ADC every 10ms but it updates one of 5 (MAT, CLT, Batt, ADC6, ADC7) so every one of them is updated every 50ms. So if you have a 60ms pulse, it should be seen every time.

Jean
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HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

????
Last edited by HOODEY on Sun Nov 13, 2011 8:56 am, edited 1 time in total.
420aRaf
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Re: Knock Detection with variable sensitivity over RPM

Post by 420aRaf »

Jean,

Ok ill try 60 :mrgreen:

HOODEY,

There are actually 4 crystals. The crystals are mainly for establishing a baud rate of 115200 since there all 4 pics are connected serially. It counts frequency and uses a on board ADC from one of the pics connected to an opamp to find knock. It completes all calculations before the next cylinder as the sampling time and feedback stays solid through 10k+ rpm. Ive also added something where it checks itself to make sure it stays synced. Pulling the variables from memory is quick. The PIC does everything from the 2 4n25’s connected to the cam and crank. Even though it works very well, I still have more testing and programming to do.

Somethings odd here....

Any reason as to why you took all your pictures down? Mine are still up...

You still dodged my question as to where the verifiable results are on a scope and dyno? Wouldn't you want to show proof before you sell a product? What chip are you running 40mhz on? Is it an 18f?
-Rafiel
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