Balloon Satellite 'APSARHA'

It was a couple of years back, while browsing the internet we had come across an agency which sent small student projects stuffed inside a ping pong ball to the edge of the space! Sky is the limit is what we’ve always believed and hence this seemed quite exciting to us.We further probed into this cool concept of sending things up to this much high altitude.
In the process we came to know about balloon-Satellite, myriad types of payloads connected to it. A video once we saw featured an i-phone suspended to a free flying balloon and released in air! The i-phone was sending real time data to the receiving station till the time the balloon floated in air.
‘Balloon-Satellite’ the word itself conveys its meaning. Putting it into more simpler terms, a balloon-satellite is a balloon suspended to a payload and released into the atmosphere. While the balloon will float in air, the payload does its assigned job.
Being amateurs in payloads & satellite subsystems, the idea of sending a simple payload in air suspended to a weather balloon till a certain altitude appeared just appropriate to get started off with.
During our visit to RSRW Santacruz, IITM Pune, IMD Pune and TIFR Hyderabad, we got to know more about weather balloons, high altitude balloons, the weather monitoring sensors used by them, etc.We decided to go with weather monitoring payload for our first balloon experiment. Our main objective in it was to test the communication link. 

Fig. 1 - Testing model of Balloon Satellite APSARHA

After a lot of research and hard work, we have completed designing the prototype and coding for the primary launch. We are planning to cover an altitude of 1 km in the primary launch which will be a tethered one and have temperature, pressure and humidity sensors. Along with that, we have also interfaced a GPS module on the circuit for tracking the balloon satellite.

We have also carried out the following tests successfully: 
·         Indoor short range test for measuring the temperature and pressure values along with the GPS co-ordinates]
·        Outdoor short range test
·        15 meters medium range test

We have received accurate data in all of the above tests with minimal data loss. Further, we plan to complete the following tests on the balloon prototype:
·         Deep freezer test- receive the weather data with the circuit kept in freezing temperature
·         Long range test on land
·         Vertical long range test at altitude of 50-60 feet

We are planning to complete those tests soon and to go ahead with the tethered launch.

Passion & perseverance has brought us a long way with Balloon-Satellite! The team is learning & exploring something new at every step. Looking forward to share our knowledge & looking forward for some interactive inputs from the readers.