Home made GPS logger

[steve_k]

What are you using for your voltage reading since the Arduino ADV can only handle 5v?

[zozie]

it runs on a 7V switching regulator, but I read the actual voltage with a voltage divider then calibrate it from software. I could use one of these to be very precise but it's also just a voltage divider......

http://www.phidgets.com/products.php...duct_id=1135_0

[steve_k]

Ah yes, simple enough. Very cool project you have going.

Originally Posted by zozie

it runs on a 7V switching regulator, but I read the actual voltage with a voltage divider then calibrate it from software. I could use one of these to be very precise but it's also just a voltage divider......

http://www.phidgets.com/products.php...duct_id=1135_0

[zozie]

I've been playing with the refresh rate, I think it's good enough.... I did the turns at idle with my car. It logs every second. I guess for straight hwy cruising you could do every 5 or 10 seconds but if you're in the bush at low speed 1 second is necessary IMHO

[yatman]

zozie...I was reading your thread start on the iPhone and therefore didn't notice you were Canuck and a Ham....you're on to something pretty cool here for people who don't realize they NEED this farkle...atta be...keep at it and if you can get a web service to connect with Iridium or a sat link via some Ham or such then I shan't consider the InReach I'm lusting over...good stuff...
yatman
VE7YAT.

[zozie]

Originally Posted by yatman

zozie...I was reading your thread start on the iPhone and therefore didn't notice you were Canuck and a Ham....you're on to something pretty cool here for people who don't realize they NEED this farkle...atta be...keep at it and if you can get a web service to connect with Iridium or a sat link via some Ham or such then I shan't consider the InReach I'm lusting over...good stuff...
yatman
VE7YAT.

Thanx for your kind words. I'm getting some quotes back on Monday to see how much it would cost to make them. I want three versions. A basic one with a battery tray, as small as possible with just an on/off switch. The 2nd one with external power connector and some switches for pause etc... The third will have a built in LCD with the info shown above and maybe bluetooth. Depending on the quotes, the first and second one should cost less than 80 bucks to make, the 3rd one would be more because of the LCD and voltage monitor, but I still can't see it costing a whole lot more. Programming it all is a bit time consuming but that's what my job is for

[OaklandStrom]

This is a super cool idea.

I've wanted to put something similar on my bike, but didn't want to deal with running my smartphone all the time. This could be easily installed under the seat, connected to the bike battery, with the antenna & button(s) mounted on the dash.

I'm looking forward to making on, and playing with the software.

[Attico]

Very very cool. Color me interested.

I could use this for sure. I think this kind of logger would be much better than using a regular gps. You also would have the same limitations that garmin and othere seem to impose.

You could also use this to geotag your photos by reconciling the logger with your camera...just need to ensure your time is in sync.

I will be honest, keeping it simple is best. A box with a status led, 2 colors.

Red, on and recording. Green on, but paused.

2 switches. On/off, and pause.

All the ancillary stuff i personally would use since i have a regular gps.

Really awesome though.

[Grinnin]

Originally Posted by zozie

I've been playing with the refresh rate, I think it's good enough.... I did the turns at idle with my car. It logs every second. I guess for straight hwy cruising you could do every 5 or 10 seconds but if you're in the bush at low speed 1 second is necessary IMHO

I think that your once a second is great.

G_____ logs whenever something (other than Lat/Lon) change. I just figured that you read the GPS input, compared it to the last entry, and logged if the new one was different. Does the GPS module provide direction of travel or would you have to calculate this? When on straight roads there are very few entries, but when there are lots of changes it logs often. If you stop, it stops logging until you move again.

But as I said in the first line of this reply, your once-a-second is great. It's easy now to provide the memory for it.

[zozie]

Yeah memory is cheap now. An 8GB sd card will last you a while

[Ceri JC]

Nice device. I was talking with a fellow GPS geek a year or so back and he said GPS device really wanted, was a small, cheap, lightweight GPS that was just a simple on/off switch, LED to show it was on and for it to do nothing but sample every 30 seconds or so and write co-ords to a .gpx file on an SD card in it. Main thing would be long battery life and ability to read the resultant file on the device itself was irrelevant. This looks pretty close to that.

[AdrianB1]

I have a similar home built device, but older and less potent :) It is quite small and it works on 4 regular AA batteries or rechargeables (easier to find than 9V) and the endurance is around 60 hours of operation on 2500mAh rechargeables. The storage is micro SD and I found it a bit unreliable on the road as the card may move in the slot at shocks and lose contact, so I had to add a warning on the display. It is writing 1 position per second, good enough for almost anything. I use Google Earth usually to analyze the tracks.

Due to lack of 2-3 line display at that time mine is using a single line display; I found it to be almost useless anyway as I am never reading the display except at startup to check the available SD space and the GPS fix; I use the device only as a tracker and I am using the smartphone as GPS navigator and map.

The precision is quite good, except for altitude, and the temperature sensor is useless if you carry it in the backpack. In the end a tracker needs to be small, light, sturdy and reliable and the battery to last as long as possible - this is why the screen and Internet connection are not something I need.

Size of the box: 11.5x6.5x4 cm (~ 4.4"x2.5"x1.5").

[HairyLeg]

Great idea, and amazing that you can do this yourself and tailor it to do exactly what you need.

I was after something to log a continuous trail, regardless of how I was travelling.
For those who can't wait for this project to finish, just try Googling or EBaying "GPS Data Logger", I did about 18 mths ago and found one of these:



http://www.transystem.com.tw/product...4&sid=21&id=56

It shows a continuous read-out of speed (amongst other things).
It also has Bluetooth if you want to hook a laptop to it while running.
I put a left-over 2gig Micro SD card in it. Records for weeks, once per second, using 2 AAAs per day. Used it across Vietnam, Cambodia, Thailand on buses, bikes, ferrys, taxis etc. Even worked on planes.

Just a suggestion for an alternative while Zozie's is being developed.

[zozie]

There is a slight problem.... The GPS module I'm using doesn't display speed above 199 knots which is 229mph so it might not be suitable for use on track days

All joking aside, I got some quotes back and it seems the whole thing would cost around $75-85 or so. The more I think about it, the more I think having a webservice for it would be a cool idea where all users could compare tracks etc... Would be supercool for cross country flying as well or even just gliding.

[Ceri JC]

Originally Posted by zozie

I've been playing with the refresh rate, I think it's good enough.... I did the turns at idle with my car. It logs every second. I guess for straight hwy cruising you could do every 5 or 10 seconds but if you're in the bush at low speed 1 second is necessary IMHO

On the subject of high sampling frequency; I found when analysing a crash in a built up area, it was really useful to have (whatever frequency the Zumo 660 samples at). It was even possible to see the point where I changed position in the lane to try and avoid a car and then the bike going into another lane and how quickly I pulled over afterwards.

Hairyleg: That looks great, thanks. Just did some searching (as I couldn't find that available near me). Looks like $60 gets you one of these:
http://www.holux.com/JCore/en/produc...nt.jsp?pno=341
12 hours out of 1AA battery, <39g w/o battery!
Looks ideal as a backup GPS for when you just want logging.