GPS Race Car Timer

Projects General Guidance
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I was thinking of making a race car timer that shows a flying delta (Delta-t).

My idea was to use a micro controller (doesn't matter which), an SD card module to store the data for later analysis, some sort of screen to show the live data, and a GPS module.

I like the look of the NeoGPS library so plan to use it.

I bought a neo6mv2 GPS module with the square antenna to try and see how it works etc as its cheap. I currently have it connected to an Uno (plan is to use a smaller faster controller for the final project). I have tried both hardware serial and AltSoftSerial. Both work. I can change the frequency rate, which sentences it listens for and all that stuff.

I have a few questions:

  1. Is the neo6mv2 any good for inside a car?
  2. So the problem I am having is, my plan is for this to get powered up when the race car starts, just like the go pro camera does. But I am experiencing a long time to get the first fix. 10 minutes and up. Sometimes I never get it (I'm probably too impatient and stop waiting at 15 minutes or so). But this is no good for my use case as I would have my run done before the GPS turns on. It is able to get date and time straight away. (time seems to be ~6 seconds ahead of my computer, weird) Am I doing something wrong or is this just how it works? How does it work in GPS devices that we get off the shelf? We don't wait really long for them to work. I have tried sitting outside and by a window inside, have got it working in both places, but also not working in both places. Once it got its first fix in ~35 seconds, every other time has been minutes.
  3. Is a GPS module that won't break the bank feasible for a project like this? Or is it a no go'er? I don't want to use wheel speed sensors as the car is rear wheel drive and the back wheels will likely be spinning at times and the fronts could lock up, especially in the wet, giving bad data.
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I don't think standard GPS will give the accuracy you need, I went to your link and they mentioned cm precision and standard GPS is on the order of meters.
You may be able to use GPS aided by RTK (Real Time Kinematics) to get you close to cm precisions (4-8 cm maybe)

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  1. Yes. It works fine inside my car and even in railcars!
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It would be much better if the GPS were powered separately than the car so that it has a data lock before you start the car. This is particularly so if the GPS is moved a substantial distance between power ups

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You are right about that - a UNO is kludgy. Pro Mini would be appropriate.

As long as it is on the windscreen with the antenna horizontal.

Is the battery on the neo6mv2 working?

Clearly you need it to be powered well before the ignition is on.

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