Featherweight Tracker Update - Build 130+

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kjs

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This is a continuation of Featherweight Tracker updates from the Build 127 thread found here:

https://www.rocketryforum.com/threads/featherweight-tracker-update-build-127.155873/

I added a post at the end of that thread so people get a "notification of post" and then can move on to this next thread. I created a build130+ public link that I think resolves the Dark Mode and iPad issue seen in Build 130. If we confirm them fixed without other issues, I'll make the standard releases point to them so other users get them as well. The public link for build 131 is:

https://testflight.apple.com/join/1uxEaYG4

Note that if you install via this link only, it may expire in 90ish days. The standard public link will always point to the current build. [These pre-releases let people move to the next build but still back out if they encounter any issues.]

For Build 132+, we are working on "observer mode" that allows you to tell your iPhone and Ground Station "tell me about trackers currently active in the flight area". I'll get bonus points if you can point your phone at the pads and it tells you which rockets are at the pad that have Featherweight Trackers... It will then allow you to easily select the tracker / frequency and "listen in" as they launch. [I can honestly say I'm not sure if it will cause confusion if 5 phones in the LCO area are all calling out flight data in different dialects / genders as the rocket launch... ]. If I get time, I will also include the auto KML conversion when 'sharing files'.
 
The 130+ did in fact fix the Dark Mode issue. Thanks!

Yes, I went ahead and made build 131 active for everyone since some people might not read this forum (?!?!). It fixes the dark mode and the iPad layout. Thanks for everyone's continued feedback!
 
Regarding the data download - I've just grabbed the tracker data (not the Bluetooth log) for the first time following a flight. Is it the case that it's only 10Hz until apogee, then 1Hz? Seems that way (reminds me of speed/accel data on the Raven FIP). Have I missed something? Don't get me wrong - I'm loving this - tracker first, plus data for those of us who are into it.
 

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Regarding the data download - I've just grabbed the tracker data (not the Bluetooth log) for the first time following a flight. Is it the case that it's only 10Hz until apogee, then 1Hz? Seems that way (reminds me of speed/accel data on the Raven FIP). Have I missed something? Don't get me wrong - I'm loving this - tracker first, plus data for those of us who are into it.

That makes sense to me. More sampling when the rocket is moving fast and for short duration, less sampling when the rocket is on parachute and moving slowly for a long time. The simulation programs do the same thing.

The GPS data is great. Much more accurate than baro or accel for altitude.
 
So an observer would have a second ground station receiving the same packet transmissions as the owner's ground station? Is this a one-way transmission or do ground stations send an ack back to the tracker? I wouldn't want my tracker sending additional data or processing acks from multiple other ground stations.
 
Regarding the data download - I've just grabbed the tracker data (not the Bluetooth log) for the first time following a flight. Is it the case that it's only 10Hz until apogee, then 1Hz? Seems that way (reminds me of speed/accel data on the Raven FIP). Have I missed something? Don't get me wrong - I'm loving this - tracker first, plus data for those of us who are into it.

That's right. The data is logged in the portion of the flash memory area that's not being used for running code, so switching from 10 Hz to 1 Hz after apogee is a good way to have room for longer flights in the limited space. That flash space is also used as part of the update process, so be sure to download your data to the phone before doing an update.
 
So an observer would have a second ground station receiving the same packet transmissions as the owner's ground station? Is this a one-way transmission or do ground stations send an ack back to the tracker? I wouldn't want my tracker sending additional data or processing acks from multiple other ground stations.

Correct.

Monitor mode makes it easy to receive data from other trackers on a receive-only basis.

Your ground station will only send acks to establish 2-way communication with the trackers in your own phone's device list. Also, your tracker will only accept acks from your own ground station regardless of what anyone else does with their ground station.
 
Regarding the 10Hz data, I have 3 trackers. Or I had 3 -- long story involving a basaltic return. Any way, the point is I have 3 trackers paired but only one of them gives me 10Hz data, and it's been destroyed. The other two only provide 1Hz even during ascent / boost stage. Is there something I'm missing in the setup to get to the 10Hz data?

~Dave~
 
Regarding the 10Hz data, I have 3 trackers. Or I had 3 -- long story involving a basaltic return. Any way, the point is I have 3 trackers paired but only one of them gives me 10Hz data, and it's been destroyed. The other two only provide 1Hz even during ascent / boost stage. Is there something I'm missing in the setup to get to the 10Hz data?

~Dave~

In the device list, select that tracker and see if there is a button to download data. The 10 Hz data is stored in a part of memory that is also used for the update process, so if you had flight data in there and then update before downloading the data, it will be erased.
 
Adrian or Kevin-

I flew today and do not have the download button showing up. I did have to power off the tracker and then turn it back on. I can select the tracker but no download button. Any idea on why that may be. It’s always worked good before.
Does the data get deleted if you power off the unit?IMG_5457.jpg
 
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I flew today and do not have the download button showing up

Bryan, sorry I forgot to follow up after getting back from camping. The data should stay there until either another flight and/or any STM firmware update. there have been no firmware updates since your install so it should still show up. Let me get you a debug build to see what it thinks is in memory there for flight data.
 
This version expired for me...and now I can’t open the iFIP app. Have tried the public link in this thread but it says that there are not accepting new beta testers. Anyone have a link or Adrian/Kevin is a new version coming out ASAP? Currently my trackers are bad nose weights...
 
This version expired for me...and now I can’t open the iFIP app. Have tried the public link in this thread but it says that there are not accepting new beta testers. Anyone have a link or Adrian/Kevin is a new version coming out ASAP? Currently my trackers are bad nose weights...

not sure what happened just just got a mysterious notification from TestFlight with a link and now all works again.
 
not sure what happened just just got a mysterious notification from TestFlight with a link and now all works again.

Yes, I accidentally let the build expire. Someone else contacted me so I made the next one available and then saw this post also. Sorry for the inconvenience and concern! Sadly I'm in Phoenix area so no local launches again until October timeframe... to hot to retrieve rockets! It will give me some time to work on some though as well as FIP some more.
 
I went out to Lucerne Valley yesterday to test my Featherweight GPS on three flights (Madcow 1.6" Mini-DX3 on two G125T's and one G76G). My main use would be for students to collect GPS flight data to compare with IMU data. I faced a bit of a learning curve:

1. On the first flight I started to follow the tracker with my phone, and it didn't even occur to me to take along the ground station. Not surprisingly (upon reflection) the tracking ceased to update once I got out of Bluetooth range (there otta-b-a-warnin). Surprisingly I overshot the rocket which landed about 20 feet behind me. I made sure to take the ground station with me after that.

2. After each flight I used the devices feature to download the tracker flight data and send it to my google drive because I understood it only saves the latest flight. I ended up with three data files, but only the first one was a flight. The second and third ones were from non-flight periods, even though they looked like the correct names. Just to make sure, I checked when I got home, and the third flight was definitely not on the tracker, just the third file I had already downloaded.

3. The log file had the first and second flights, but not the third. The first one showed clearly when I walked out of Bluetooth range. The second one is quite useable (10 Hz data are really nice but not absolutely necessary), but the third is missing. My iPhone announced liftoff, apogee, and the under 3000', under 2000', and the under 1000' with increments down to 200', so I know it was tracking, but the third flight is not on the log or on the tracker.

Unless I can reliably figure out how to get all of the flights recorded on either the tracker or the log I won't be able to use the system for my class (next spring, so there's a chance we'll be able to run the class). Has anyone annotated somewhere (I've looked) how to reliably record the flight data?

While I'm asking, how many units would I need to run a class with five students all trying to cert Level 1 on the same launch wave at an event. I'm hoping the answer is six (one ground station and five trackers). Has anyone tried to track 5 rockets when three or four are in the air at the same time using one ground station?

BTW, I love being able to send my data files directly to my Google Drive. That is really cool! I just wish they all had flight data.
 
Unless I can reliably figure out how to get all of the flights recorded on either the tracker or the log I won't be able to use the system for my class (next spring, so there's a chance we'll be able to run the class). Has anyone annotated somewhere (I've looked) how to reliably record the flight data?

Your phone should have all recorded packets. The 10Hz data should have a special name (with the rocket in the middle). the phone recorded data should just be the date of the recorded data.. can you send me the file (email to [email protected]).

While I'm asking, how many units would I need to run a class with five students all trying to cert Level 1 on the same launch wave at an event.

The timing of the packets are synchronized by channel so you can really only track one rocket in the air with one GS.

Not surprisingly (upon reflection) the tracking ceased to update once I got out of Bluetooth range (there otta-b-a-warnin).

I should maybe have it ask "Do you know where your GS is?" if you walk out of range...? :)
 
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.
 
Your phone should have all recorded packets. The 10Hz data should have a special name (with the rocket in the middle). the phone recorded data should just be the date of the recorded data.. can you send me the file (email to [email protected]).



The timing of the packets are synchronized by channel so you can really only track one rocket in the air with one GS.



I should maybe have it ask "Do you know where your GS is?" if you walk out of range...? :)

I double checked, and the log file on the phone was larger than the log file on the computer. I re-downloaded the log file and replotted the data and the third flight was definitely there. I don't know if the log file takes a while to update and I downloaded too soon, or what I did wrong, but the log file does definitely have the data I need for the class. Now I just need to figure out how to budget for the additional ground stations.
 
I double checked, and the log file on the phone was larger than the log file on the computer. I re-downloaded the log file and replotted the data and the third flight was definitely there. I don't know if the log file takes a while to update and I downloaded too soon, or what I did wrong, but the log file does definitely have the data I need for the class. Now I just need to figure out how to budget for the additional ground stations.

The log file on the phone is in binary format and I export as CSV / Text so I would not expect the file sizes to match - but am happy that you found the data!!
 
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