Recommendations for sensor-packed boards for model rocket telemetry project?

Development Boards Other Microcontrollers
1

Hi! I convinced my son’s Boy Scout Troop to do a model rocket telemetry project. Please advise on the best set of parts in the smallest form factor that will provide:

  • Arduino board
  • Cellular radio (we’re getting free, time-limited eSIMs to radio the telemetry data)
  • GPS (so we can find it when the wind carries it away)
  • 100g accelerometer (I’ve read 32g gets pegged during launch)
  • Battery mount (hopefully it can run on 1 or 2 button cells)

Optional sensors:

  • ambient pressure
  • ambient temperature
  • ambient humidity
  • altitude

Your advice would be greatly appreciated!

Thank you!

2

It really depends on the feature set you need and price point…

MCU, cell, humidity: We sell this kit SparkFun Digi XBee® Cellular Kit (does come with a SIM, I know that isn’t needed)

GPS: https://www.sparkfun.com/sparkfun-gps-breakout-chip-antenna-sam-m8q-qwiic.html
Accel: this one is the highest max G that we sell SparkFun Triple Axis Accelerometer Breakout - KX134 (Qwiic)
Battery: a single cell lipo is probably best https://www.sparkfun.com/catalogsearch/result/?q=battery

PHT: https://www.sparkfun.com/sparkfun-environmental-combo-breakout-ens160-bme280-qwiic.html

Altitude is a bit more tricky, you’d need to swap the GPS receiver above for one that uses RTK, like https://www.sparkfun.com/sparkfun-rtk-postcard.html (or browse the category)

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3

Hi Philip ( @theschles ),

I haven’t participated in rocket flights, but I have been involved in tracking many high-altitude balloon flights.

A standard u-blox GNSS receiver will give you altitude - provided you set the “dynamic model” to one of the “Airborne” modes. AIRBORNE4g is probably going to be the best choice for you. You don’t need RTK. I’ve used the MAX-M8 at altitudes approaching 40km and they have worked well.

The SAM-M8Q has a built-in antenna. If the rocket is spinning during flight, that will probably cause problems. Back on the ground, you want to avoid the chance of the antenna being oriented towards the dirt. You may need to think about using a separate helical antenna and position it carefully so it can always get a signal.

There are other gotchas, particularly on pressure sensors. I’ve used one model where the pressure reading wraps round at high altitude, making it appear below sea level… If you’re only logging the data, you’re fine. But be very careful if you’re thinking about using it to deploy a parachute. I’ve had good results with the MS8607. It will give you pressure, temperature and humidity.

I’ll include some links below which you might enjoy. (Watch out for cougars stealing your payload!)

Good luck. You and the Troop will learn a whole lot! Please write up the project and share it.

Very best wishes,
Paul

https://arxiv.org/pdf/1904.04321

https://arxiv.org/pdf/2004.10764

https://arxiv.org/pdf/2311.08602

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4

Thank you PaulZC.

Pressure / altitude wraps around because it’s a signed integer? Wow.

I don’t think we need to worry about that – as these rockets only go 100 to 2,500 feet in the air.

5

Hi @TS-Russell – I was hoping to find small, combined chips.

  • Would this do the job of LTE transmission? Digi Xbee 3 low power LTE (yikes, $75!)

  • Would the GPS Module do the job of determining GPS position? If I’m RTFM’ing the data sheet correctly, an Arduino chip’s serial pins could get latitude, longitude, and “Mean Sea Level” altitude directly from it

  • Accel: yep, we’d do the SparkFun Triple Axis Accelerometer Breakout - KX134 (Qwiic)

  • The PHT you recommended above would work should people want to add that.

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6

While in-range, yes…looks like LTE drops out @ about 10k feet, but otherwise yep
Also yes for interfacing with the GPS module…most any MCU can get its data over serial :slight_smile:

7

I found Waveshare has a combo ESP32, Cellular, GPS, Wi-Fi, and Camera unit for $48 (their website) $60 (Amazon). That’s a heck of a lot cheaper – and more compact – than the separate parts offered by SparkFun.