The Eclipse Ballooning Project to date has distributed system kits to 54 teams. These systems give teams, both novice and experts, a starting platform to build upon in preparation for the 2017 total solar eclipse. Below you will find a basic overview of the system kit as distributed and built during the May Practice and July workshops.
Still Image Payload:
The still image payload uses a Raspberry Pi and Pi Camera to take, store and transmit images. Transmitting images to the ground station is accomplished using a 900Mhz modem which also allows the user to indirectly send commands to the Pi such as changing camera settings, selecting images to be transmitted and tilting the camera vertically.
The video payload uses a Raspberry Pi and Pi Camera to record HD video while transmitting the feed (which is uploaded onto the internet for public viewing) to the ground station using a 5.8Ghz Ubiquiti modem. The Ubiquiti modem also allows for user commands to be sent to the on-board Pi to, for example, tilt the video camera or adjust camera settings.
The tracking payload houses an NAL Iridium satellite modem which allows for near real time tracking of the balloon for the project teams, FAA and ground station to track the balloon and payloads during a flight. The ground station collects these GPS data points and uses them to automatically adjust the antennas accordingly towards the balloon. The Iridium modem also works as the line of communication for users to send the cutdown command to the balloon should the flight ended prematurely.
The cutdown system mechanically severs the line connecting the payload string to the balloon. Should the flight need to be ended prematurely, the user simply sends a “termination email” to the balloon via the Iridium network. The email is received by the Iridium modem, and by way of two linked Xbee radios (one housed in cutdown system and the other in the tracking payload), the cutdown command is sent to the cutdown system initiating a motor and cutting blade severing the line between the payloads and the balloon. The payload string then parachutes down to Earth for recovery.
The ground station tracks the balloon during flight while gathering the video stream being transmitted at 5.8 Ghz with the dish antenna and communicating with the still image payload at 900 Mhz using patch (flat square) and Yagi (short metal rods protruding perpendicularly out of a metal support) antennas. The video feed is then uploaded onto the internet for near real time viewing.