Motion sensor not using PIR


I want to include a motion sensor in a GPS recorder circuit. PIR is out, since there won't be any light where it's mounted.

The purpose is simple: an on/off switch - on when the ship is moving, off when not. On a smartphone GPS app, I can opt to either use or not use the capabilities of the sensor.

Has anyone seen or built anything like I need? Online searches show only PIR setups; not going to work.



You haven't provided enough information for us to be able to help you. What conditions will exist when the ship is moving that won't when it's not moving?

I guess it will always be moving as it bobs about on the waves - that makes it very difficult .
As said , more information on what you are trying to do would help

PIR doesn't make sense in the first place. It could detect people moving around on board, not motion of the boat itself. And of course boats always move.

I want to include a motion sensor in a GPS recorder circuit. PIR is out, since there won’t be any light where it’s mounted.

PIR works in total darkness.

Some interesting responses, thanks!

I'll expand a little. I'm using a very small GPS recording module on a cruise. I want it to run while the ship is underway, and stop when it ties up at the dock. -- continuing the cycle until the end of the trip, without any intervention from me.

Yes, the boat may bob up and down when port, but I didn't consider that because it should not be a factor.

Why? Settings in the better smartphone GPS apps allow one to specify a horizontal distance; it must be greater than the setting in order to turn on. I'd like to be able to set such parameters in a sketch, and accomplish the same result. I think "fence" when I visualize it. Anytime the boat is outside the "fence", it turns on. Not so when stopping. After a specified amount of time, again user set, the GPS shuts off.

It seems reasonable that if a smartphone can do it, it can be done via Arduino and sensor(s). Maybe not.


It seems reasonable that if a smartphone can do it, it can be done via Arduino and sensor(s).

The smartphone is using GPS to do that. If you want to use the GPS, of course it can be done. But you're asking about how to do it without GPS. That's completely different.

Why don't you want to use GPS?

There are GPS modules that interface with an Arduino. It's a matter of programming to ignore small movements.

You'll need an SD card or other external memory to store your data.

Alternatively look at the ESP8266 processor, it has 4 or even 16 MB of flash memory that can be used to log your data (should be plenty for basic time and location logging). It connects over WiFi allowing it to get the time from the internet, and for you to read back the data.

Thanks for all the suggestions, everybody.

I'll have to re-visit this another time, cruise countdown clock moving fast.

What I'm going to do on this trip is turn the units on and off manually. Fortunately, when the unit is turned off, then on, a new path file is created. Makes it easy to track each separate day, then manipulate the data when I get home.

The module I'm using is a based on a custom fabricated PCB, with Arduino coding modified for the specific purpose. Draws about 50mAh, so it will run, and record, unattended about a year with a 25,0000 mAh power pack, 4 gB sd card lasts about 8 months.

Rambling a little here, hope some may find it useful.



Why stop there.
Install navigation software on a GPS enabled device, like openCPN (freeware).
Download the charts for the area you're sailing in, and you can have much more than just waypoints.