The Eggfinder - A Low-Cost GPS/RF Tracking System

madcow rocketry
Advertise with us
The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Made some progress with my Eggfinder/HC-06 talking to a Droid. We loaded the Bluetooth GPS app. and now have streaming NMEA data, satellite position and strength and a map that shows the location of the TX. No distance or heading to it though, and the maps go away when we are out of range from our Wi-fi.
So we loaded the Polaris Navigation app and got about the same stuff. So we loaded GPS Rocket locator and when "mock GPS provider" was enabled in the Bluetooth GPS app., Rocket locator shows where the rocket is, and when it's not enabled it shows where we are. No rocket distance or bearing. So close to having a device that can walk you right to the rocket, but one step away. Has anyone got this setup working yet?
 
OK. Looks like I'm on my own, so here is what I did. I emailed Francois Girard :<[email protected]>
He is the designer of the Rocket Locator app. He told me to turn off Bluetooth GPS after I get the indication that the Eggfinder Tx has locked. Turn on "Rocket Locator" and the red light on the HC-06 will stop flashing and go solid red. This means the HC-06 is connected (paired) to Rocket locator. The trick is to make sure there are no other bluetooth devices paired to the Android.
My system is working now! Took my N/C for a ride and the range has increased dramatically with the new antenna's.
I redesigned the N/C on my 5" Jart to remove the allthread and any other metal near the antenna. The two holes in the bulkhead are from the U-bolt originally used for an anchor point:
008.jpg


The 1/2" plywood bulkhead is mounted in the N/C coupler against a fiberglass ring epoxied near the top. It is retained by three small screws recessed so the N/C can slide over them:
009.jpg


I also added three pem nuts to secure the N/C to the coupler. The Y harness is 1/2" kevlar looped around a hardwood dowel. I flattened two sides of the dowel and glued it to the bulkhead:
006.jpg


Then I drilled two holes through the dowel and zip tied the antenna and sled to the dowel. The only metal at that end is the small screws holding the bulkhead to the coupler and they are over 2" away from the antenna. The sled was made from 1/8" plywood and the "battery box" is 1/4" plywood:
005.jpg


The foam taped to the top of the sled fits snugly into the N/C and holds everything steady. (I hope)
The battery is a Tenergy 2c lipo (7.4v and 900mAh).

I got the box and switch to hold the Eggfinder Rx and HC-06 bluetooth module at Fry's Electronics:
001.jpg


Cut a window through the lid so I can see if the LED's are lit up correctly:
003.jpg


I repaired a small crack in the fin fillet of Jughead that it got on it's first flight last month, so the rocket is ready for it's second flight. This will be my first 75mm motor, the CTI L995 Red Lightning. Since the sim's I did for it's first flight were off quite a bit when it flew on a K750, I'm thinking this flight will really test the range of the Eggfinder, possibly in excess of 10,000 ft. It will also be carrying my CSI RF tracker beacon in case something doesn't go right with the GPS.
Hopefully I can get to the TRA/PHX launch this month on the 26th. That way I won't have to worry about the waiver....


.
 
Hey Wayco- what are the details for that launch? Thought phx lost their field, but maybe I'm thinking of another club.


Sent from my iPhone using Rocketry Forum
 
soopirV said:
Hey Wayco- what are the details for that launch? Thought phx lost their field, but maybe I'm thinking of another club.


Sent from my iPhone using Rocketry Forum
Click to expand...

The next TRA/PHX launch will be held at the Eagle Eye launch site on April 26th and 27th. I sent you a PM regarding the cancelled launch last month near Quartsite.
 
I'm ready to start building my Eggtimer and I have a question. I just bought a new welding station. It has a thermostat control set the temperature of the iron. So what temperature should I set it to when working on the Eggfinder? Thanks!
 
Wayco said:
Made some progress with my Eggfinder/HC-06 talking to a Droid. We loaded the Bluetooth GPS app. and now have streaming NMEA data, satellite position and strength and a map that shows the location of the TX. No distance or heading to it though, and the maps go away when we are out of range from our Wi-fi.
So we loaded the Polaris Navigation app and got about the same stuff. So we loaded GPS Rocket locator and when "mock GPS provider" was enabled in the Bluetooth GPS app., Rocket locator shows where the rocket is, and when it's not enabled it shows where we are. No rocket distance or bearing. So close to having a device that can walk you right to the rocket, but one step away. Has anyone got this setup working yet?
Click to expand...

That's the problem with the Rocket GPS locator, no maps without internet connection. From what you've said in your posts, the GPS Rocket locator doesn't like to play with other connected B/T devices? I have a Nexus 7 with a B/T keyboard and B/T mouse. It I want it to run reliably, I should run it bare with just the
EF receiver connected? Anyhow, I've seen the same behavior, once bonded by the GPS Rocket locator app, the HC-06 goes from flashing to solid.

I sent a note to Girard and though the GPSRL program is nice, it would be better if it had some sort of portable maps. Yes one can use it bare but it's nice to
be able to see where the landing site is in relation to roads and landmarks. The APRSDroid app for APRS tracking does have a version for open source maps so one can download a free mapfile for their intended location: https://aprsdroid.org/osm/
This doesn't help those of us who use the EF and other similar trackers though.

Having portable maps would make GPSRL more usable for Android devices that aren't cell phones.

I've used the EF receiver as a GPS source for Xastir and had Xastir retransmit the data as an APRS packet for ham use. All of the incoming data from the EF receiver is used. Position, speed, altitude direction is incorporated into the packet that can be retransmitted in APRS form every 2.5 to 3 seconds. Of course this is of use only for Ham folks but is very nice to be able to monitor a flight with APRS equipment if one desires.

Now the kicker is to have a "map in hand" to carry. A laptop is fine to have record the flight from inside a vehicle but triapsing out in a field it's not easy to carry
(or read in the sunlight for that matter).

Android based phones with internet access are great for B/T pairing with the EF receiver which I might add is a very easy thing to add-on. But.... if one is out in the boondocks with no internet link a portable mapping solution is better. For that, I think we'll all have to wait for for a portable solution. MapSphere is fine for laptop use, the maps are downloadable and portable but a portable "map in hand" eludes one. Kurt
 
Kester specifies 600F-700F (315C-371C). 650F should be fine, the key is to make sure you get enough heat on the pads so that the solder flows out, and to remove the heat once it has.

chuck5395 said:
I'm ready to start building my Eggtimer and I have a question. I just bought a new welding station. It has a thermostat control set the temperature of the iron. So what temperature should I set it to when working on the Eggfinder? Thanks!
Click to expand...
 
If the map program is based on Google Maps' API, you should be able to load the map in the comfort of your home and use it out in the field without Internet. Where I fly, the maps are pretty useless, there really aren't any discernable landmarks that would make a map or satellite image more useful than the heading/distance to the waypoint (your rocket).

ksaves2 said:
That's the problem with the Rocket GPS locator, no maps without internet connection. From what you've said in your posts, the GPS Rocket locator doesn't like to play with other connected B/T devices? I have a Nexus 7 with a B/T keyboard and B/T mouse. It I want it to run reliably, I should run it bare with just the
EF receiver connected? Anyhow, I've seen the same behavior, once bonded by the GPS Rocket locator app, the HC-06 goes from flashing to solid.

I sent a note to Girard and though the GPSRL program is nice, it would be better if it had some sort of portable maps. Yes one can use it bare but it's nice to
be able to see where the landing site is in relation to roads and landmarks. The APRSDroid app for APRS tracking does have a version for open source maps so one can download a free mapfile for their intended location: https://aprsdroid.org/osm/
This doesn't help those of us who use the EF and other similar trackers though.

Having portable maps would make GPSRL more usable for Android devices that aren't cell phones.

I've used the EF receiver as a GPS source for Xastir and had Xastir retransmit the data as an APRS packet for ham use. All of the incoming data from the EF receiver is used. Position, speed, altitude direction is incorporated into the packet that can be retransmitted in APRS form every 2.5 to 3 seconds. Of course this is of use only for Ham folks but is very nice to be able to monitor a flight with APRS equipment if one desires.

Now the kicker is to have a "map in hand" to carry. A laptop is fine to have record the flight from inside a vehicle but triapsing out in a field it's not easy to carry
(or read in the sunlight for that matter).

Android based phones with internet access are great for B/T pairing with the EF receiver which I might add is a very easy thing to add-on. But.... if one is out in the boondocks with no internet link a portable mapping solution is better. For that, I think we'll all have to wait for for a portable solution. MapSphere is fine for laptop use, the maps are downloadable and portable but a portable "map in hand" eludes one. Kurt
Click to expand...
 
cerving said:
If the map program is based on Google Maps' API, you should be able to load the map in the comfort of your home and use it out in the field without Internet. Where I fly, the maps are pretty useless, there really aren't any discernable landmarks that would make a map or satellite image more useful than the heading/distance to the waypoint (your rocket).
Click to expand...

I've tried with the Nexus 7 FLO (no cell phone inside) but that is not the case with GPS Rocket Locator. I haven't been able to get any consistency with it. More often than not with testing off the internet, I get a blank screen.
I've done scads of downloading but unless there's a trick to get it to work with the Nexus 7, I can't get it to display
well enough to trust that the maps are going to remain there offline.

With MapSphere, one actually selects the area they want and it will download the map. It doesn't use Google Maps
anymore. Actually, one of the developers emailed me that the program is unsupported and will not be updated.
There are still useable maps though. Kurt
 
ksaves2 said:
That's the problem with the Rocket GPS locator, no maps without internet connection. From what you've said in your posts, the GPS Rocket locator doesn't like to play with other connected B/T devices? I have a Nexus 7 with a B/T keyboard and B/T mouse. It I want it to run reliably, I should run it bare with just the
EF receiver connected?
Click to expand...

how the H... , you need a mouse and a keyboard on the field for when you try to locate a rocket ?
 
I just set my laptop on the roof of my car and come back after the rocket has landed to get the lat/long reading from MapSphere, and I plug that into MotionX on my iPhone. Works great, unless the battery dies (lesson learned...)
 
:grin:
Area66 said:
how the H... , you need a mouse and a keyboard on the field for when you try to locate a rocket ?
Click to expand...

Ahhhh, I use the unit for other stuff too.:wink: But you are very correct Gerard, I don't need to, to use it out in the field to track rockets . If extra B/T items mess up GPS rocket locator, then I'll use it bare.:grin:r
I'm glad that extra bit of information was posted so I know not to fret about it. Kurt
 
I agree with Cris, maps are useless out on the playa or desert, most cactus look the same from above. I have a Garmin GPS in my Jeep, and use it to find my way to where the rocket is. If Rocket Locator can give me bearing and distance, I can figure out the rest. If it can't, I'm thinking I need a second receiver plugged into the laptop saving NMEA data. That way I can input the co-ordinates in the Garmin, drive that way until the mobile Rx picks up signal and use the Android to find the rocket.
Rocket Locator doesn't play well with other bluetooth devices paired to an Android. That could be a good reason some of you have had problems with it. I have no practical in the field experience with any of this stuff, I'm going on what is happening when I use it in my neighborhood. Next weekend Juan and I are going to the TRA/PHX launch. Both of us will have operational Eggfinders in rockets that will fly in excess of 10,000 ft. If we get them back, we should have some good data to share.
 
michigander said:
my plan laptop to get coordinates , put #'s in GPS and walk to rocket


View attachment 169576
Click to expand...

You are correct but I am reminded of the Ham who was trying to track with APRS and couldn't get the proper units from his Kenwood D72A
into his Garmin 60CsX. I showed him how a $17.00 cable could do it automatically and he is a very happy camper now. The rocket appears in real time on the Garmin with every received packet, no muss, no fuss.
If one is going to use the manual approach, plan ahead and make sure they can do the manual data input and have the units jive between the
two rigs.

I did a range check by myself today by sticking my laptop in my vehicle plugging in the EF receiver and using a mag mount antenna like this:

https://www.ebay.com/itm/Cellular-c...ectional_Network_Antennas&hash=item5afcd4544a

Yeah they overrate their specs but if it's half as good as it says, it's still decent.

I then used a Mobilinkd TNC with another H/T to retransmit the EF position packets to APRS once every 2.5 to 3 seconds using Xastir.
Stuck a 2m/70cm magmount on the roof of the car.

Started walking away with my D72A and the EggFinder transmitter. I could monitor the position report as it was received at the laptop.
It was re-transmitted out on 144.800 so I could see it on the D72A. I tried to send a position packet back to the laptop from the D72A as it has it's own GPS. I only got a few packet through because of the high update rate I had Xastir set at:
testcrossband.jpeg

I unfortunately should have changed the track colors before saving but save for a few positions, there was good correlation and the receiving station missed some packets when I stood right behind a garage.

I suspect that out in an open area the EggFinder will hold it's own. One can use a patch antenna or something like I show above. I'd like to see some reports of flights above 10k using a decent receiving station. Kurt
 
Just got mine about 90 mins ago!

IMG_20140428_134213692.jpg

I still need to attach the USB and battery connections and trim the antennae, but otherwise finished. Cant wait to try it out!

My only gripe is the vertical resistors, which I would prefer being horizontal, or surface mount. I get why it is the way it is, but I still have my preferences :p
 
Landru said:
Just got mine about 90 mins ago!

View attachment 170424

I still need to attach the USB and battery connections and trim the antennae, but otherwise finished. Cant wait to try it out!

My only gripe is the vertical resistors, which I would prefer being horizontal, or surface mount. I get why it is the way it is, but I still have my preferences :p
Click to expand...

Great,
Consider doing a battery pack and B/T module for the receiver unless you are going to use the receiver stationary with a laptop.
Get an HC-06 B/T module for the receiver and one can bond with any Android device that can do B/T. Makes it more portable.

Kurt
 
Landru said:
My only gripe is the vertical resistors, which I would prefer being horizontal, or surface mount. I get why it is the way it is, but I still have my preferences :p
Click to expand...

I haven't started on mine yet, but I've been considering psuedo-potting mine with dobs of hot glue.
 
Juan and I both flew our Eggfinders yesterday. He was braver than me, and went over 9000 ft. I will let him give the details, but the bottom line for me was when the system regained lock, the Rocket Locator app. gave him bearing and distance to the rocket. So when it came time for me to fly, the backup Rx wouldn't hook up properly to my laptop, but the Android was working with Rocket Locator, so I flew "Jughead" on a CTI K650 Smokey Sam to 4200 ft. Rocket locator tracked the whole flight, including the boost! I know it was slower and lower than Juan's flight, but I'm very pleased with the way the system worked.
A couple of things I noticed, first that the audio from the Android/Rocket locator will tell you when you have both signals. Two separate tones when both GPS devices are acquired. It gives you bearing, distance and altitude at the top of the screen, and displays your position, the rockets position and an arrow to head you toward your rocket. As I was walking to the rocket, the receiver picked up the signal and gave me it's exact location. Walking along, looking for the rocket, I walked past it, so when I looked back to the Android, the arrow was pointing back to my left. Turned around and followed the arrow right to it.
Now I'm ready to fly it again on the big 75mm L900. Might be a while though, that was the last TRA/PHX launch of the season. I might be able to hit the ROCstock launch in Calif. in June though, if it isn't too hot.
 
ksaves2 said:
You using a patch antenna? If you're getting data from 9k' with a stock wire antenna that's pretty good. Kurt
Click to expand...

I was the one that flew to 9K, not Wayco. Wayne flew to 4k and tracked the whole flight. Now I did not track the whole flight, I picked up signal again around 6000ft and I did not except it to track it at Mach 1.5. My Eggfinder does have the stock wire antennas, I think I would of track the whole flight with duck antennas. Has anyone else flown these past 10K?
 
jus_rockets said:
I was the one that flew to 9K, not Wayco. Wayne flew to 4k and tracked the whole flight. Now I did not track the whole flight, I picked up signal again around 6000ft and I did not except it to track it at Mach 1.5. My Eggfinder does have the stock wire antennas, I think I would of track the whole flight with duck antennas. Has anyone else flown these past 10K?
Click to expand...

As opposed to a patch antenna, one could consider something like this:


https://www.ebay.com/itm/Cellular-c...rk_Antennas&hash=item5afcd4544a#ht_2621wt_977

You can look for a better price and the magnet isn't good for driving but it's good for stationary use. I gound tested and was still going strong at 1 mile
with lots of obstructions. Kurt
 
Wayco said:
Juan and I both flew our Eggfinders yesterday. He was braver than me, and went over 9000 ft. I will let him give the details, but the bottom line for me was when the system regained lock, the Rocket Locator app. gave him bearing and distance to the rocket. So when it came time for me to fly, the backup Rx wouldn't hook up properly to my laptop, but the Android was working with Rocket Locator, so I flew "Jughead" on a CTI K650 Smokey Sam to 4200 ft. Rocket locator tracked the whole flight, including the boost! I know it was slower and lower than Juan's flight, but I'm very pleased with the way the system worked.
A couple of things I noticed, first that the audio from the Android/Rocket locator will tell you when you have both signals. Two separate tones when both GPS devices are acquired. It gives you bearing, distance and altitude at the top of the screen, and displays your position, the rockets position and an arrow to head you toward your rocket. As I was walking to the rocket, the receiver picked up the signal and gave me it's exact location. Walking along, looking for the rocket, I walked past it, so when I looked back to the Android, the arrow was pointing back to my left. Turned around and followed the arrow right to it.
Now I'm ready to fly it again on the big 75mm L900. Might be a while though, that was the last TRA/PHX launch of the season. I might be able to hit the ROCstock launch in Calif. in June though, if it isn't too hot.
Click to expand...

That sounds like a real world test of the electronics payload to me....swish !

Time to mount it in your svelt and sleek Blackstar for the win ... but the 75mm L900 should rock also .

Kenny
 
KenRico said:
That sounds like a real world test of the electronics payload to me....swish !

Time to mount it in your svelt and sleek Blackstar for the win ... but the 75mm L900 should rock also .

Kenny
Click to expand...

The 3" Blackstar would have the same problem the 5" Jart had. Metal rod holding the bottom bulkhead onto the N/C. Really attenuated the signal from the Eggfinder until I rebuilt the N/C to remove it. With a 5" diameter, the screws holding the coupler/shoulder to the N/C are over 2" away, not possible with the 3" N/C on the Blackstar.
My next build will be the 4" Darkstar Extreme, and it's gonna need a GPS also. I'm looking at alternatives, and depending on my budget, I might spend some big bucks to assure that I will get it back. Meanwhile, the Jart might be a good test vehicle to see how far we can push the Eggfinder. L900 could take it over 10k, but my sims haven't been all that reliable.... And I can't talk about the K750 flight down at Desert heat.....:blush:
 
Best I've done is 8,400' (you were there!). Wire antenna on both ends. Yes, it did drop out, yes, it did pick it back up on the way down, and yes, I did find the rocket... exactly where the Eggfinder said it would be. I guess I need to get a bigger rocket (MD 54mm... GL Firestorm looks about right.)

jus_rockets said:
I was the one that flew to 9K, not Wayco. Wayne flew to 4k and tracked the whole flight. Now I did not track the whole flight, I picked up signal again around 6000ft and I did not except it to track it at Mach 1.5. My Eggfinder does have the stock wire antennas, I think I would of track the whole flight with duck antennas. Has anyone else flown these past 10K?
Click to expand...
 

Similar threads

cerving
Eggtimer Rocketry Annual Holiday Sale - 2023
2 3
Replies
61
Views
5K
wonderboy
W
atestani
EggTimer GPS-TX/OpenLog/Proton and Google Earth Flight Track
Replies
11
Views
608
BigDeal4
BigDeal4
cerving
Eggtimer Quasar and Eggfinder LCD Receiver Firmware Updates
Replies
14
Views
1K
cerving
cerving
JoeTekcor
Receive Eggtimer data with SDR
Replies
4
Views
537
OverTheTop
OverTheTop
MarsLander
Eggtimer LCD serial output...fail, Help?
Replies
3
Views
145
cerving
cerving

Latest posts

Back
Top