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VR emulator for board soldering validation

Posted: Wed Dec 16, 2020 5:43 pm
by AndreyB
We need a VR emulator, mostly for quality assurance of assembled units but also to test alternative VR conditioning designs.

EDIT: ONLY for quality assurance of assembled units

Here is proposal #0:
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Re: VR emulator

Posted: Wed Dec 16, 2020 6:42 pm
by AndreyB
An even simpler proposal
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Re: VR emulator

Posted: Wed Dec 16, 2020 8:48 pm
by mck1117
Those ignore the true nature of a VR sensor's output. The tricky part is the fact that it goes through the zero crossing slowly, not quickly as these do. (It's much closer to a sawtooth than a square wave).

Re: VR emulator

Posted: Wed Dec 16, 2020 9:18 pm
by qwerty-off
1:
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Looks like real vr sensor. A transformer is required, which increases cost and complexity.

2:
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Almost good. A bipolar signal source like MAX232 is required. Diagnostics will not work because VRIN2 is connected to GND. Will there be more problems?

3:
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Another way is to connect a unipolar signal through a capacitor. An additional level converter is required because the Vpk-pk signal must be greater than 5V (Vmiddle * 2) for TLE8888 and max9926 or Vcc for NCV1124. Diagnostics will not work too.

Anyone have any other suggestions? Which of these options is the best choice?

Re: VR emulator

Posted: Wed Dec 16, 2020 9:28 pm
by Fonzie
Could not use a sound card and a power amplifier or a transformer for the voltage swing?

Re: VR emulator

Posted: Wed Dec 16, 2020 9:55 pm
by mck1117
doesn't even need a PA, you could just drive it directly from a headphone output

Re: VR emulator

Posted: Wed Dec 16, 2020 10:48 pm
by AndreyB
Fonzie wrote:
Wed Dec 16, 2020 9:28 pm
Could not use a sound card and a power amplifier or a transformer for the voltage swing?
No, this is a lot of manual labor to set things up for each run. This is an extremely overcomplicated, heavy, large and expensive setup.

The focus right now is to have hardware quality assurance validation rig - need a self-contained fully automated testing rig. In this topic we are developing a building block.

Re: VR emulator

Posted: Thu Dec 17, 2020 3:33 am
by kb1gtt
Doesn't the discovery have a headphone jack?

Re: VR emulator

Posted: Thu Dec 17, 2020 3:38 am
by AndreyB
kb1gtt wrote:
Thu Dec 17, 2020 3:33 am
Doesn't the discovery have a headphone jack?
Any additional scope of software is x100 the total effort of hardware implementation. Also I would prefer not to lock myself into discovery for multiple reasons. My strong preference is on a 100% hardware solution for quality assurance at this point, VR signal has to be only as valid as MAX/TLE/NCV expect it to be.

Re: VR emulator

Posted: Thu Dec 17, 2020 11:03 am
by kb1gtt
How about 36 dip switches connected to a shift register so you can emulate a 36-1 wheel? 100% hardware and emulates a common crank pattern.

Re: VR emulator

Posted: Thu Dec 17, 2020 11:07 am
by kb1gtt

Re: VR emulator

Posted: Thu Dec 17, 2020 1:17 pm
by AndreyB
On this level we kind of do not care for trigger shape, all we need to see is register incoming VR signals. Also we already have digital output for trigger sequence shape so that thing MCU can take care of already.

If we would be testing trigger shape on this level we would have tested with 3 tooth 1 skipped wheel, not 36 tooth one skipped just for simplicity.

Re: VR emulator for board soldering validation

Posted: Mon Sep 20, 2021 4:14 pm
by AndreyB
Working circuit to simulate the 3 sensor trigger pattern of a Honda D/B/H
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Re: VR emulator for board soldering validation

Posted: Tue Sep 28, 2021 12:09 am
by Simon@FutureProof
I dont know if this helps or not but I have been checking simply using an old vr abs sensor on a couple of pins to push onto the vr input pins and a fork to wiggle it between, this is able to make the ecu at least see a real rising falling of a vr and so far no issues.

Very low tech but it has been working.