Tracking hardware?

[Mushtang]

Is there a lightweight piece of equipment that will record the flight of a rocket using the GPS system?

I'd love to know the maximum speed and height for each flight, and plot the track on a computer screen, assuming I'm able to recover the rocket.

 

[JDcluster]

The Garmin Astro will record flight info, not like a flight computer it does work for rocket applications. One down side is: it will lose lock when exceeding Mach.

JD

 

[BEC]

Why GPS? There are a number of barometric-based altimeters that will do what you describe. My personal favorite is the new Perfectflite P-nut.

Now if you want to plot the ground track on a computer screen, then you do need to go GPS. I have no direct experience with this aspect in rockets. I do have the necessary bits from EagleTree systems to do this in model airplanes (see https://www.eagletreesystems.com/MicroPower/micro.htm).

 

[Mushtang]

I just assumed GPS would be the best way to get a 3D image of the track. Wouldn't using just air pressure give you only altitude? That would be enough to get max Altitude I suppose, but if there's a cheap GPS option I'd like that more I think.

 

[BEC]

Yeah, if you want a 3D view of the track, GPS is it. Height and speed can be had from a barometric device, but not ground track.

What does "lightweight" mean to you? I expect that answer will constrain the possibilities (or not) quite a bit....

 

[mikec]

There are cheap GPS data loggers (e.g., https://www.i-gotu.com), but I've had mixed success with them in rockets because many GPS chipsets go nuts with the rapid vertical position change at boost, even if they stay in lock.

 

[Mushtang]

Yeah, if you want a 3D view of the track, GPS is it. Height and speed can be had from a barometric device, but not ground track.

What does "lightweight" mean to you? I expect that answer will constrain the possibilities (or not) quite a bit....

As someone that has been in this hobby for almost a whole month, I'm not sure that "lightweight" means anything other than "what my little rockets can carry".

 

[mikec]

As someone that has been in this hobby for almost a whole month, I'm not sure that "lightweight" means anything other than "what my little rockets can carry".

When I say I've had mixed success with the cheap, small iGotU logger, that was in HPR rockets (like it did a poor job in my Level 3 rocket.) Maybe it would work better in an low-power rocket.

 

[BEC]

As someone that has been in this hobby for almost a whole month, I'm not sure that "lightweight" means anything other than "what my little rockets can carry".

Well, that's the key bit, isn't it? What are your "little rockets"....or what motors do you want to use with this logging ability?

For some of us on this forum, "lightweight" means half an ounce - we fly primarily "low power rockets" or what long ago were the only kinds of model rockets - up to C or D impulse motors. For others on this forum, "lightweight" might mean a pound or two - the high power aficionados.

I don't know of anything that can do GPS that makes much sense for low power models - even the Eagle Tree setup that I pointed to would be up over two ounces for the logger, the GPS sensor and a small li-poly cell to power it for awhile.

I just did some looking for what mikec was talking about.... looks like under $60 and under an ounce for IGotU-120 - but it looks like the shortest interval it can be set to take data is every 5 seconds. That won't be much good in the boost phase of the flight.

 

[mikec]

I just did some looking for what mikec was talking about.... looks like under $60 and under an ounce for IGotU-120 - but it looks like the shortest interval it can be set to take data is every 5 seconds. That won't be much good in the boost phase of the flight.

No, you can set it for different intervals above and below a specified speed threshold. I set mine to record at 1-second intervals if moving and 5-second if stationary. Other than the problems with going nuts at boost it worked great -- it would be perfect for an R/C plane, and much cheaper than any other solution I know of. Weight is 0.8 oz.

 

[scsager]

Is there a lightweight piece of equipment that will record the flight of a rocket using the GPS system?

I'd love to know the maximum speed and height for each flight, and plot the track on a computer screen, assuming I'm able to recover the rocket.

Having a GPS in your rocket can help MAKE SURE you get the rocket back. Provided the GPS sends live data back to you (telemetry). This is normally not inexpensive. Here is a $400 example.

Another way to get data - without the GPS and without the telemetry - is to use a recording altimeter. The AltimiterTwo is an inexpensive way to capture a lot of neat data about the rocket flight.

 

[deputy6765]

Why GPS? There are a number of barometric-based altimeters that will do what you describe. My personal favorite is the new Perfectflite P-nut.

Seems like a nice little unit but no channels for Drogue/Main events ? I went to the web site to check, did I miss something ?


Darin

 

[BEC]

Seems like a nice little unit but no channels for Drogue/Main events ? I went to the web site to check, did I miss something ?


Darin

What you're looking for, then, is the Pnut's first cousin, the Stratologger. I'm flying LPR - all motor eject - so don't need what you're looking for.

 

[JoeG]

Having a GPS in your rocket can help MAKE SURE you get the rocket back. Provided the GPS sends live data back to you (telemetry). This is normally not inexpensive. Here is a $400 example

.

I am evaluating one of these and it will do everything you want. It will plot a course on a laptop in real time if you have all the required accessories. It is not the easiest to use and I still haven't flown mine. Also you need to have a technician license to legally operate it.

The Garmin Astro is larger and am not sure about tracking altitude since its intended use is as a dog tracker. but I believe that you can upload to a computer and get the flight path from point a to b. I can tell you that the range on the Garmin is phenomenal. It has been tested by me to over five miles. Don't ask.

The Garmin along with a recording altimeter will give you all the info you need and is much easier to set up than anything else that I have found.

 

[Tominator 2]

When I say I've had mixed success with the cheap, small iGotU logger, that was in HPR rockets (like it did a poor job in my Level 3 rocket.) Maybe it would work better in an low-power rocket.

Mike,
I have been looking into alternative tracking methods for my rockets too. Did you only loose lock at boost? Or during the whole flight? Do you think it would work in a high G flight (<80 G's) in a 38mm min dia rocket?
Thanks,
Tom

 

[mikec]

Mike,
I have been looking into alternative tracking methods for my rockets too. Did you only loose lock at boost? Or during the whole flight? Do you think it would work in a high G flight (<80 G's) in a 38mm min dia rocket?

I think it's sensitive to the exact satellite configuration. I flew it three times; the first flight's data (K400 to about 7k feet) was plausible and the second and third on a different day (one on an M1297 to 12k+ feet, one on an I180 to about 2500 feet) were mostly garbage from launch to landing. Seems like a very poor prospect for a high-g flight.

 

[TD Sky]

I loved my 900Mhz BRB GPS setup on sub-Mach flights. Worked great. Sometimes the rocket would descend behind a hill, but if I went to the last coordinates transmitted, the receiver would pick up transmitter again and I could walk right to the rocket. Its last flight was well over Mach (Rasaero predicted 1.7). The boost was perfect and I actually heard the apogee deployment (you can even here it on the video from the camcorder on the ground). But the last transmitted coordinate, which the receiver screen displayed just a few seconds after launch, was over a quarter mile away. Not likely. Never regained lock. Rocket is lost. I can understand temporary lock loss but if I had known Mach+ flights had the potential to loose lock permanently, I never would used it for those flights. Lesson learned I guess.

 

[Tominator 2]

I think it's sensitive to the exact satellite configuration. I flew it three times; the first flight's data (K400 to about 7k feet) was plausible and the second and third on a different day (one on an M1297 to 12k+ feet, one on an I180 to about 2500 feet) were mostly garbage from launch to landing. Seems like a very poor prospect for a high-g flight.

Yeah that doesnt sound like it will work for what I am looking for. I would rather not spend the 250-300 bucks for a BRB when Im only going to use it three or four times a year. Consequently, I am looking at other options.
Sorry to hijack the thread a little bit...

 

[Lentamental]

If you don't need gps, but still want some sort of radio tracker, you might want to look into directional "beepers" that emit a radio signal that you track down with a directional antenna.

https://www.walstonretrieval.com/sub-3.htm
https://www.jbgizmo.com/
https://www.arrowantennas.com/arrowii/440-5ii.html

and some guys tiny gps that I don't know much of anything about:
https://www.geocities.com/rdh82000/APRS/TinyGPS.htm

edit:
It also looks like these guys do the directional antenna tracking thing, and they are present on this forum
https://www.radiotracking.com/index.html