EXPERIMENT RECORD N° 9515
MIRIAM-2 Balloon Deployment System Test
  1. 2015 • 63rd ESA Parabolic Flight Campaign
Physical Sciences:
  • Technology
A310 ZERO-G Airbus
K. Bayler (1), T. Lehmann (1)
(1)  
Mars Society Deutschland e.V.
Balanstrasse 79
81539 München
GERMANY
Tel:  
+49(0)89.480.02.752
e-mail:  
kb.marssociety-d@gmx.de
zero_g@gmx.de
The 63rd ESA Parabolic Flight Campaign (63rd PFC) took place from 26 October 2015 to 06 November 2015 and was conducted from Mérignac-Bordeaux airport. While the first week was dedicated to the preparation of the 11 experiments selected by ESA´s science committees and the experiment integration into the airplane, during the second week three parabolic flights (3, 4, 5 November) were performed.

BACKGROUND

MIRIAM-2 is a spaceflight mission simulating critical functions of the ARCHIMEDES Mars Balloon Mission of the Mars Society Deutschland e.V. (MSD). ARCHIMEDES shall allow for the first time performing scientific measurements of the Mars atmosphere and magnetic field strength with instruments carried by a balloon, which will be inflated in space, be decelerated by the Mars atmosphere and descend slowly in the Mars atmosphere (Link: http://marssociety.de/?page_id=27).

The objective of the MIRIAM-2 mission is twofold: deploying a densely packed 4-m balloon in free space, and measuring in the thin upper Earth atmosphere the aerodynamic loads on the balloon under conditions resembling the loads to which the 10-m ARCHIMEDES Mars Balloon will later-on be exposed when entering the Mars atmosphere. The measurements shall allow validating the aerodynamic flow calculations for the ARCHIMEDES Mars mission, on which the balloon design is based.

The MIRIAM-2 balloon and instrument carrier have been developed and manufactured by the MSD to the specifications of the 10-m Mars Balloon. Its scientific payload is similar to the one for ARCHIMEDES. The balloon will be densely packed into a specific container, deployed in an altitude of about 200 km, inflated and released before starting its free-flight scientific mission.

SCIENTIFIC OBJECTIVE
Subject of the experiment during the parabolic flight is the verification of the correct function of the initial balloon deployment, which is crucial for the success of the ARCHIMEDES Mars Balloon Mission. The balloon deployment system consists of the container itself and the associated fully automatic system for deploying the balloon. The parabolic flight experiment shall demonstrate that the balloon is being correctly deployed to its full length of 4 meter after being stored in a densely packed condition. Inflation and release of the balloon are not subject of the test.

RELATED RESEARCH
Archimedes balloon release mechanism and balloon package behaviour under zero gravity conditions
40th ESA Parabolic Flight Campaign - 2005

A fully functional model of the MIRIAM-2 balloon deployment system will be fixed in a test rig, which in turn will be fixed to the aircraft. The balloon will have been packed and in the container beforehand in the development facility using specific tools. There will therefore be only one single test run possible. The balloon container will be opened by a pyrotechnic cable cutter device releasing the balloon spring-loaded. The balloon will then extend to its full length of approximately 2 m without being inflated.

The cable cutter will be activated by the test operator approximately half-way into a flight parabola. The deployed balloon will be captured and safeguarded by a member of the test team.

APPLICATION OF THE RESEARCH
The results of the experiment shall demonstrate the validity of the design and all functionalities of the MIRIAM-2 balloon storage and deployment devices and of the balloon design and construction itself. The balloon will be tested later-on in order to verify its health condition following the parabolic flight test.

It was observed that after correct activation of the cable cutters the balloon package only moved by 2-3 cm out of the container, and the “blossoms” didn’t move at all.

It was then tried to push out the balloon manually by pressing on the back side of the container, which also did not work. Not even pulling at the pod could release the balloon. Only after pushing on the back side of the “blossom” in the following parabola the balloon moved out of the container and the blossom fully unfolded. The balloon then was in the pre-inflation state as required.

This means the test is failed since this action needs to happen without manual interaction.

The conclusion is, the spring mechanism on the back side of the „blossom“ is not strong enough to deploy the balloon and has to be made stronger. Therefore the mechanism needs a re-design. It is planned to do force measurements and also ground-based deployment tests with a dummy, before as a final test, another deployment test in zero-g is planned.

click on items to display

Figure 1: The hard ware. credit: Mars Society Deutschland

Figure 2: The hard ware. credit: Mars Society Deutschland

Figure 3: Test setup in the A310 in deployment configuration. credit: Mars Society Deutschland

Figure 4: Pod after activation of cable cutters, with pod only deployed by 2-3 cm in the 1st of the two test parabolas. credit: Mars Society Deutschland

Figure 5: Deployed balloon after manual help in the 2nd test parabola. State of the deployed balloon is as required. credit: Mars Society Deutschland

Figure 6: The balloon after unfolding (with manual help by Frédéric Gai from Novespace) credit: Mars Society Deutschland
 
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