Featherweight Tracker Update - Build 130+

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I had an issue with my tracker during a launch this weekend. Just before the launch button was pushed my GS lost connection with "John Tx" (my tracker). Much later after a futile search for the rocket, I noticed that there is a tracker named "root", that I didn't add, in iFIP. The software saved the location of each transmitter. I plotted the locations in google maps. Image john is my tracker out on the Pad. Image root is the GPS location iFIP stored which is where all the cars were parked on the side of the road. My theory is that my GS linked up with "root" somehow just before the launch because both Tx are showing up on the GPS screen with saved coordinates. However, it's odd that "root" has a negative serial number and no channel. One last note, I downloaded the new firmware earlier that morning from my house. At the field all I did was turn both units on after the rocket was loaded onto the launch rail.

It's entirely possible I screwed this up, but I'm curious to know what happened. Appreciate any and all feedback.
 

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My tracker is named root "my last name" I was launching all day at mmwp but shouldn't affect anyone else there is not frequencies like the old days
 
I updated the firmware before my flight on Saturday @ Mini Midwest Power. That seemed to go well, but then things went down hill.

My tracker lost connectivity during boost and I didn't pick it up again until 1,000' agl Fortunately it did keep the connection all they way down so I was able to retrieve my rocket. But once on the ground I lost connectivity again.

When I returned home I tried for about half an hour to re-connect to the tracker but it never connected. :(

You can see in the log that there are all "0"s where data should be during the launch. Then afterword there was spiritic data logged.

Here's the plot of the data I did get:
LOC_Sandhawk_L2.jpg

Is there some way to reset the tracker and start over again?
 

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Thanks Locksmith, the problem is most likely something on my end that I don't recall, as this tracker has performed very well in the past.
 
Yes although I may do a build 135 tonight that has firmware updates turned off so I can verify there isn't an issue with 134. I've had two users who had problems. One was update from firmware > 1 year old, but one was more recent firmware.

Revisiting this; it ended up that the two firmware updates mentioned above both were both well understood (build 134 was the fix for one user and the other user had serial numbers 11 and 49 which was a pre-release version that I was going to have to update manually anyway.

I recommend using build 134 that includes a firmware update for the Cypress. We will not be releasing a build 135 with updates disabled. I will continue developing off the build 134 source.

Thanks!
 
My tracker lost connectivity during boost and I didn't pick it up again until 1,000' agl Fortunately it did keep the connection all they way down so I was able to retrieve my rocket. But once on the ground I lost connectivity again.

When I returned home I tried for about half an hour to re-connect to the tracker but it never connected. :(

You can see in the log that there are all "0"s where data should be during the launch. Then afterword there was spiritic data logged.

Dave - can you send me an email at [email protected] and we can try to get this figured out? Thanks!
 
Last weekend I flew my trackers for the first time, on a 2 stage flight. Before launch I could see both trackers had good GPS fix. It did not detect launch, so had no voice callouts and did not record the flight. But it kept a good fix on both units and pointed me right to them for recovery. What do I need to do differently?
 
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Thanks for all the help.

This system is still very janky. I flew multi stage again last weekend and did nothing differently from before, same rocket. Before launch I had NO confidence that it would track. I checked it at the pad, it showed connection to both trackers and the ground station, fine. When I got back to the flight line the timers on the GPS and track screen were counting up as if it had lost connection (plus several minutes). The only reason I said go to launch was if I went over to the comm screen I could see packets coming in. Track screen showed bogus data. Despite it showing no connection it detected launch and vocalized the flight.

Once on the ground the track screen showed it correctly about 4,400 feet away. Once I got under about 1,000 feet from it it started showing 39,000 some feet away. Thankfully the direction arrow continued to work because the distance was garbage data until I was right on top of it.
 
First I'm sorry I didn't see your post on June 28th. Please feel free to email me at the address above if you don't get a reply to a forum post within a reasonable time.

This system is still very janky. I flew multi stage again last weekend and did nothing differently from before, same rocket. Before launch I had NO confidence that it would track. I checked it at the pad, it showed connection to both trackers and the ground station, fine. When I got back to the flight line the timers on the GPS and track screen were counting up as if it had lost connection (plus several minutes). The only reason I said go to launch was if I went over to the comm screen I could see packets coming in. Track screen showed bogus data. Despite it showing no connection it detected launch and vocalized the flight.

Once on the ground the track screen showed it correctly about 4,400 feet away. Once I got under about 1,000 feet from it it started showing 39,000 some feet away. Thankfully the direction arrow continued to work because the distance was garbage data until I was right on top of it.

Are you saying that you have two trackers and one GS with them all set to the same frequency? If so, the trackers are both trying to transmit at exactly the same time slice and frequency, so will be causing interference with each other (and possibly corrupted packets). The normal mode for a two stage would be with two ground stations each paired with the different trackers on a different frequency.

As an aside, I have a two stage rocket that I need to get started working on, and was going to see if the phone app could be improved for that type of scenario (but still might likely require a GS per tracker).
 
My theory is that my GS linked up with "root" somehow just before the launch because both Tx are showing up on the GPS screen with saved coordinates.

My tracker is named root "my last name" I was launching all day at mmwp but shouldn't affect anyone else there is not frequencies like the old days

[I see I missed some of these posts while working in quarantine - sorry about that.]

And actually, there are still frequencies and if you are on the same channel, they transmit at the same time slice with synchronization based on GPS time (so pretty close to overlapped). It does sound like your GS started either getting some of both transmitters - and since root was closer after launch, it might have been what your GS was picking up on more than "John Tx". And "John Rx" wouldn't know the serial number or frequency (for the display) as that comes when pairing BlueTooth pairing. I am surprised it added it to the "My Devices" list based on a packet on the same frequency but that might be a clue for me to determine where to ignore those packets.

Let me talk to Adrian about whether there is a way to mitigate or warn you in this situation.
 
Wait, all of a sudden you need a separate ground station for each tracker? Seriously?? Are you offering a full refund or shipping me a free ground station for this false advertising? So now what do I also need another iPhone too? Maybe exactly what I need should be properly documented so we don't have to guess? "One ground station" is clearly posted right on the front of the webpage.

Screenshot_20200731-073304~2.png
 
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Sorry; yes you can have one GS and two trackers, but the GS is listening to only one tracker on one frequency and you have to switch the phone to the other tracker / frequency to pick up the other tracker. I was trying to understand if you tried to set both trackers to the same frequency/channel. They could interfere with each other then.

So, back to my original question before I confused the issue ... did you have your units on the same frequency or different frequencies?

Thanks!
 
Yes same frequencies per the user manual.

The website says "two or more stages" not "rockets" with ONE ground station. So you're suggesting I put the trackers on different channels and then DURING THE FLIGHT go into the ground station settings, change the frequency, and see if I can pick up the other unit??
 
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So if your phone is paired with the GS and both trackers, and if they are on different frequencies, then it should only involve switching between the selected tracker to change the frequency of the GS (you shouldn NOT have to go into Devices> Settings to change the frequency).
 
Yes same frequencies per the user manual.

The website says "two or more stages" not "rockets" with ONE ground station. So you're suggesting I put the trackers on different channels and then DURING THE FLIGHT go into the ground station settings, change the frequency, and see if I can pick up the other unit??

Just our of curiosity, why would you need to switch to the other tracker during the flight?

Here's what I would want and expect to happen-

Before the flight I verify that both trackers are up and running and have lock. Then switch to track the sustainer for the flight, since that's where the exciting telemetry is coming from. The only time I'd ever switch back to the booster tracker is when it's time to go find it. That's where the "easy switching between displays" comes in, right?

Not trying to be argumentative, I'm just trying to understand what the practical purpose for switching between trackers during the flight is.
 
Before the flight I verify that both trackers are up and running and have lock. Then switch to track the sustainer for the flight, since that's where the exciting telemetry is coming from. The only time I'd ever switch back to the booster tracker is when it's time to go find it. That's where the "easy switching between displays" comes in, right?

The ground station is listening on just one frequency. So it is only listening on the frequency it is set to, so it only picks up the one stage. The other stage would have none of the packets recorded. And if you set them both to the same frequency, they you get cross talk / corruption.
 
Doesn't the ground station need to be set up on the same frequency as the tracker in order to receive live telemetry? If not, why even set it on the GS?
 
Just our of curiosity, why would you need to switch to the other tracker during the flight?

To get live data. So I have a close proximity to it's final location. It will not necessarily pick up the signal once it's on the ground. Definitely didn't last weekend until I was within a couple hundred feet.
 
To get live data. So I have a close proximity to it's final location. It will not necessarily pick up the signal once it's on the ground. Definitely didn't last weekend until I was within a couple hundred feet.

Ah I get it now. I was missing the part that Kevin just explained about it not tracking both at the same time.

Staying tuned.
 
Kevin,

How quickly can the ground station switch frequencies? Would it be possible to have a setting on a two stage flight to listen to frequency that is currently being displayed 95% of the time but have the GS automatically switch to the other stage, grab a few packets, and switch back? This would get you a last known position on the other stage in case the link was lost once it was on the ground.

I can imagine a case where I was watching the sustainer and never saw the booster after burn out. If the booster lands behind a hill or small rise it might be hard to get close enough to reestablish a connection without at least a hint where to go to. I know you have the possibility of other rockets to see the booster and relay the lost rocket signal, but this relies on another rocket going up with a Feather Weight tracker and you can't count on that.

On a side note I'm hoping to use a Feather Weight tracker in my next project, is there any progress on software for Android?

-Brian
 
My tracker is named root "my last name" I was launching all day at mmwp but shouldn't affect anyone else there is not frequencies like the old days

There ARE frequencies and it sounds like other trackers on the same frequency will corrupt your connection. On top of that, the software doesn't warn you. Not good.
 
Doesn't the ground station need to be set up on the same frequency as the tracker in order to receive live telemetry? If not, why even set it on the GS?

Yes the GS needs to be at the same frequency as the tracker. So with a two stage flight you have to have the trackers on different frequencies so with only one GS, you need to switch back and forth with the selector wheel on the GPS page. I once had the feature where you could swipe up and down on the tracking page to change rockets, but then people did it accidentally while tracking and didn't realize why they lost tracking (their other tracker wasn't even on).

How quickly can the ground station switch frequencies?

Would it be possible to have a setting on a two stage flight to listen to frequency that is currently being displayed 95% of the time but have the GS automatically switch to the other stage, grab a few packets, and switch back? This would get you a last known position on the other stage in case the link was lost once it was on the ground.

I can imagine a case where I was watching the sustainer and never saw the booster after burn out. If the booster lands behind a hill or small rise it might be hard to get close enough to reestablish a connection without at least a hint where to go to. I know you have the possibility of other rockets to see the booster and relay the lost rocket signal, but this relies on another rocket going up with a Feather Weight tracker and you can't count on that.

I'll need to test the frequency change timing, that but the rocket transmits at 1hz and finishes that in < 0.5 seconds. then it listens for other 'community' transmissions during the second 0.5 seconds. There is also the issue if the bluetooth has any transmission issue, then the phone might think it commanded the change but it didn't actually happen and then you are listening to the wrong tracker.

I have some other things to do first, but I have a two stage kit that I need to start working on and then might see if I can optimize it better for two stage flights.

With regards to Android, I haven't been working on that so can't readily comment.
 
I am taking all of this good basic configuration information in. I have 2 trackers and one GS and it is good to know the proper settings.
 
Yes the GS needs to be at the same frequency as the tracker. So with a two stage flight you have to have the trackers on different frequencies so with only one GS, you need to switch back and forth with the selector wheel on the GPS page.

When I do this it loses the GS and the trackers unless I go over to the device screen, refresh, and go back to the GPS screen.
 
When I do this it loses the GS and the trackers unless I go over to the device screen, refresh, and go back to the GPS screen.
I have seen this behavior also; Kevin is working on it. If you don't switch screens to the devices page and back again, it will eventually update the display but it takes a while.

edited to put in the quote I was responding to
 
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I just installed build 158, and two out of three units [one GS, one Tracker] installed all three things, one unit [Tracker] installed only the first two [but not the LORA] and said it was done. I power cycled that unit and it said it needed to update and then installed the LORA update.

I have a few questions:
1. It says it has been tracking Tracker#1 for "323d 2...", now with the update it now shows the whole thing, which is good, but how do I get it to stop tracking?
2. The header on the GPS page flashes something with a rose colored fill once per second. It seems like it is toggling between the two trackers' headers, showing one most of the time and flashing the other for maybe 0.1 seconds, except it is not that simple. When I select the tracker that is on, it flashes blank with the rose back ground. When I select the tracker that is off, it flashes between the two different tracker headers. Tracker#2 has been tracking for 436d 11:56:28, 29, 30,...
This behavior is undesirable, is there a way to make it stop flashing stuff?
3. Now that Tracker#1 has found some GPS satellites, when I select Tracker#1, it does not flash the header at all. When I select Tracker#2, which is still turned off, it it flashes the two headers with about equal time, with Tracker#2 still at 436d, etc., but no color banner. The GPS display fields seem to still be showing Tracker#1 data. What does all this mean and what is it trying to tell me?
4. With both on and Tracker#2 not having any satellites yet, when I select Tracker#2 the banner flashes rose colored but the header content stays the same. When I select Tracker#1 the header flashes back and forth between the two headers with Tracker#2's header in color. With some satellites, it just flashed alternately with no color banner, but with Tracker#2 it still does not flash the other header. This behavior is unclear. Why does it flash for one but not the other? When it is flashing the header back and forth, who's tracker data is it showing?
5. Lastly, I set it down for less than a minute and sometimes it goes back to the tablet's home screen [sometimes it does not], and sometimes from the home screen when I then get back into the app, it has lost part of its knowledge of the ground station and the trackers [but still has comm traffic with both], other times it is fine. This also happens at the LCO table sometimes, which is very disconcerting. Is there a way for it not to need constant attention to keep tracking?

br/

Tony
 
I updated last night too. I'm also getting the red flashes. It appears to have something to do with looking for the other tracker. (I have two trackers and one base unit.)

I love this GPS system, but I wouldn't mind a little feedback about how to manage multiple tracking units on one base system. I have never flown the two of them in the same day. I'm honestly a little nervous about doing that.
 
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