BUoyancy Balloon Bus Lifted Experiments

The project BUBBLE (BUoyancy Balloon Bus Lifted Experiments) is a small high altitude balloon project from KSat. We provide a stratospheric balloon for a payload and organize the launch and recovery.

Project Goals

The bus system for the weather balloon is developed by KSat. The system guarantees location determination over the entire flight phase via a double redundant system and ensures a landing by parachute. The bus system will be rescued after landing.

The payload is provided by an external institute or other project. A maximum payload of 1 kg can be carried.



BUBBLE1 is flying the payload from the IRS. The payload are two camera sensors. One camera is mounted with an objective. Both sensors are pointing upwards in the sky, to measure the brightness.
The payload is a
precursor mission of the ESBO project.

As camera a Raspberry Pi camera is used, which points upwards with 30° to the horizon. The raw data is stored and analyzed for further analysis after the weather balloon has been rescued.

The Gondola

The gondola consists of two pyramids with a square base.

In the upper pyramid is the main computer (CCU) together with the payload computer (PCU). The GPS antenna is mounted on the top for a good reception. The communication module for Iridium is also located on the top to guarantee reception. Furthermore, the payload of BUBBLE 1 is mounted at the top and points out through an opening in the wall.

Upper Pyramide (CAD)

Lower Pyramide (CAD)

A pool noodle is inserted through the lower pyramid to increase inertia of the gondola and thus reduce any movements. Also, the battery and the sensor unit are fixed in the lower part.

Below the pyramids, attached to a cord, hangs the reprogrammed weather probe, which acts as a third communication link to the ground station and runs completely independent with its own battery.