MicroSat Circuit Sculpture

Description

Here is a small satellite sculpture based on brass tube and copper wire.
It is a "functional" micro satellite that captures every hour a photo and then sends it by wifi in FTP.

The circuit consists of an ESP32 Camera connected to a super capacitor by means of a DC-DC converter to maintain a 3.3V stability even if the capacitor voltage passes above or below 3.3V.
A voltage divider bridge checks the voltage of the super capacitor to avoid starting the ESP32 if the voltage is too low.
The super cap is charged by four 5V little solar panel.

After running the code the ESP32 goes to sleep for 15 minutes and restarts if the voltage is sufficient.
The ESP32 code then captures a photo, sends it by FTP to the website and then calls a php page to send telemetry and the website generates a GIF of the day.

The MicroSat has found its place, suspended, in my astronomy observatory.

Here is an example of a photo taken by the MicroSat camera:

Animation generated by the website of all photo taken by the MicroSat camera for the day :

Files

MicroSat-01.gif

Gif made by the MicroSat

Graphics Interchange Format - 7.00 MB - 03/14/2023 at 02:27

Preview

Micro-SAT ESP32 and Website Code.zip

Micro-SAT ESP32 and Website Code

x-zip-compressed - 8.38 MB - 03/14/2023 at 02:27

Download

Schematic_MicroSat_2023-03-13.png

Schematic of MicroSat

Portable Network Graphics (PNG) - 60.63 kB - 03/14/2023 at 02:27

Preview

Discussions

greziref wrote 03/20/2023 at 13:12

Great project, I love it.

How many time did the capa give you ?

Are you sure? yes | no

BLANCHARD Jordan wrote 03/23/2023 at 04:32

Hard to say, continuously, maybe sends 2 to 3 photos without sun, otherwise 2 photos spaced 15 minutes apart without sun.

The problem is that even without anything connected, the supercap is slowly discharging, and connected with the ESP in standby the converters consume some energy. But I think it’s optimisable.

Are you sure? yes | no

petem001 wrote 03/15/2023 at 20:14

Hi! Nice sculpture,

I would like to know what are the up and down voltage converter you are using?

Are you sure? yes | no

BLANCHARD Jordan wrote 03/16/2023 at 22:22

Hi! Thanks :)

For the Step-UP: https://fr.aliexpress.com/item/4001054709058.html

And for the Step-down: https://fr.aliexpress.com/item/32891890551.html

I know that now it is possible to have just one module that step-up and regulates the output if the input voltage goes beyond the output voltage like this: https://fr.aliexpress.com/item/1005002587844860.html , but I didn’t have any at that time.

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kimstik wrote 03/15/2023 at 17:43

I suggest to increase values of R1 and R2 at least 10 times in a way to reduce current leak +cap in parallel to R2.

Best way is to use micropower monitors like STM1061 /TPS3840/MIC841/etc

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petem001 wrote 03/15/2023 at 20:15

good comment.

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BLANCHARD Jordan wrote 03/16/2023 at 22:38

Hi thanks for your comment, I just used what I had on hand when I made the circuit, now I have additional KA75330 and KA75450, I can maybe do it again with a KA75330 connect on the pin enable of the ESP32...

I don't think 66K at 5V leak a lot of current, like 75µA ?

I wonder if the internal resistance of the supercap isn't consuming more current ^^

Are you sure? yes | no

Virtual_Burrito wrote 03/26/2023 at 09:35

I'm new with this kind of projects, could you share the circuit and code where you use the KA75330?

Also another question, is it possible to store the taken images to the sd card you can insert in the ESP?

Are you sure? yes | no

MicroSat Circuit Sculpture

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