This is very cool!<p>At first, I had some questions about why you'd use a Raspberry Pi for this, but once I realized that video was being recorded as well it made more sense. I'm quite impressed.<p>For increasing sample rate, it really depends on where the problem is. The Pi is recording video and managing the sensors - are these two tasks competing with each other?<p>Perhaps using another controller to deal with the sensors and telemetry transmission could help (if contention is actually the problem). Something like the ESP32 in the D1 Mini form factor would easily fit in the rocket. If I was doing this, I'd ignore the ESP32's onboard radios and use the LoRa module since it seems to work quite well in this application.<p>[0] <a href="https://johnjonesfour.com/2020/10/03/model-rocket-telemetry-part-1/" rel="nofollow">https://johnjonesfour.com/2020/10/03/model-rocket-telemetry-...</a>
Curious what other boards you considered?<p>You mention using Adafruit libraries & working in Python. The Adafruit feather boards focus on low power situations & some include battery slots.
<a href="https://www.adafruit.com/feather" rel="nofollow">https://www.adafruit.com/feather</a>
Hi, do you have technical details for that? I don't really see any.<p>><i>There must be a buffer that holds a certain amount of camera footage before saving it to disk. Because the battery disconnected in-flight, no flight video saved. I'd like to figure out how to write video data more frequently in case the battery issue happens again.</i><p>Disk or SD card?<p>I'm seeing RSSI. What signal are you measuring the strength of? Given that you talked about problems losing footage and buffering, I suppose you are not transmitting in near real-time but instead save to disk and get the data <i>afterwards</i>? Given that you have a link, why not send the video stream to your ground station directly?<p>I worked with Raspberry PI to acquire data from fitness trackers with Bluetooth Low Energy (BLE), then transmit using 4G dongles. We serialized the data into protobufs and used Kafka in the backend. We also used the setup for other things.<p>><i>The software performed well, but I'd still like to increase the data capture rate. There are Adafruit libraries for the components I'm using in C++, so I'm considering rewriting air.py in C++, but I'd really love it if someone talked me out of that.</i><p>I don't think you have to re-write anything in C++. I'm pretty sure the bottleneck is not the language.
> The software performed well, but I'd still like to increase the data capture rate. There are Adafruit libraries for the components I'm using in C++, so I'm considering rewriting air.py in C++, but I'd really love it if someone talked me out of that.<p>Would that really improve data capture ? How much throughput is it captured that python can't keep up (is that even the right kind of questions) ?
400 feet doesnt seem very high (to a bystander like me). I made a 19mm diameter sugar rocket with my kids, tied it to a bamboo stick for stability and electrically started it. The thing went so high that we visually lost sight of it.<p>Is this because my power to weight ratio is so much lower?
We're using a ESP32 as the "brains" of a Rocket tracker. Having Wifi to confirm GPS lock is pretty nice.<p>I flew it yesterday with a Quectel L-80/MediaTek 3339 chipset, seems to have performed fairly well.
<a href="https://forum.ausrocketry.com/viewtopic.php?f=32&t=6547" rel="nofollow">https://forum.ausrocketry.com/viewtopic.php?f=32&t=6547</a>