PRE2016 3 Groep19

Group members

• Jeanpierre Balster - 0864027
• Mike Beckers - 0943224
• Elise Levert - 0883583
• Joël Peeters - 0939193
• Kady Schotman - 0958295
• Elise Verhees - 0950109

Planning

A rough planning of the whole project containing the milestones in the process:

Week 1: Decide on the subject by brainstorming.

Week 2: Do some basic research about the chosen subject and make a presentation about it (including objectives and approach).

Week 3: Create a planning (inclusive a presentation about it), finalize definition deliverables, define milestones. Start working on specific tasks of the literature research.

Week 4: State-of-the-art literature research. Decide solution on Thursday.

Week 5: Do further more detailed literature. Begin Netlogo simulation.

Week 6: Refine solution based on literature. Continue on Netlogo simulation.

Week 7: Finalize NetLogo deliverable.

A Gantt chart of the planning is given below. LR is literature research. SR is solution research, so combining the knowledge from the literature research to find the best solutions. For more detailed explanation on the different tasks, see section 'Approach'.

Case study

Group 19 will work on researching a space cleaning robot. This is currently a relevant problem; millions of pieces of space debris are orbiting the Earth. These pose a threat to satellites and spacecrafts which can collide with the debris (forming even more debris). Even if from now on nothing would be shot into space anymore, the amount of space debris would still increase, since pieces of debris can collide with each forming new pieces of debris. The problem needs to be solved using an Artificial Intelligent autonomously functioning device, since it is not possible to control the device from Earth, due to the time it would take to receive and send information from and to space (the debris would already be out of reach before the information is send back to Earth). The robot should be able to autonomously complete the following tasks: locate the debris, either collect and store the debris or push it in the right direction, return to Earth. Furthermore, research should be done on how to get rid of the debris. Will the robot burn the debris upon reentering of the Earth's atmosphere or will it bring he debris back to Earth (for the use of recycling).

Objectives

The objectives are answering the following research questions through literature research:

Furthermore, a NetLogo simulation will be made.

Approach

The approach is to realize the following deliverables:

1. A literature research on:

• The current impact of the space debris on society
• The current impact of the space debris on enterprises
• The current ways of finding space debris
• The current ways approaching the debris (to catch it)
• The current ways of retrieving debris from space (catching and storing or pushing in the right direction)
• The current ways if getting rid of the debris (burn up/bring back to Earth)
• The current ways of returning the device to earth

2. A concept for the best solution / improving existing solutions

• The impact of the solution on society
• The impact on enterprises of the solution
• The best way to find debris
• The best way to approach it
• The best way to retrieve the debris from space
• The best way to get rid of it
• The best way to return to earth

3. A Netlogo simulation

• Which will simulate the search path
• Which will simulate transporting the debris

USE aspects

The relevant USE aspects in our project.

Retrieving Mechanisms

Electrodynamic tethers can be used to remove space debris. In this option, the tether attaches itself to a piece of debris and current is induced along the tether. A Lorentz force is created between the tether and Earth’s magnetic field, causing the space debris to accelerate. This can significantly decrease the time needed for the object to de-orbit, particularly for debris close to earth (Barbee).

A momentum exchange tether could also be used to change the path of debris. Here, the tether, moving at high speeds, will attach to a slower moving piece of debris. If the debris is released at its highest retrograde velocity, then it will come closer to the atmosphere (lower perigee) (Barbee).

Lasers for vaporization are rather unfeasible as they require high precision and power. The debris moves quickly and somewhat unpredictably, so the precision is a huge issue. Also, the power requirement is beyond our current capabilities. The object could also potentially explode if it contains some unspent propellent. A laser in space could even infringe upon UN regulations (Barbee).

Surface material could be sent into space and affect the travel path of all objects which hit it. The object would be at risk of breaking and creating more space debris (Barbee).

Reflective Solar Sails are another alternative. They could attach onto debris, and as solar photons strike the sail, the object will in turn accelerate. The issue with solar sails is that it may not significantly alter the acceleration of the orbiting bodies unless it is acting on the body for months. At low altitudes this technology couldn’t be used due to corrosion (Barbee).

Another general concept is to produce streams of air from within the atmosphere that will be directed towards debris to change its travel path. Methods of producing these air streams vary from balloons to high altitude planes. This approach could affect multiple pieces of space debris in one attempt and is at no risk of creating more space debris if it fails (David).

The use of ion beams is also considered to help move debris; one such example is the Ion Beam Shepherd. The concept is to create an ion beam which will produce a force that can propel the debris forward. This also forces the mission to move in the opposite direction with the same force; thus, two beams are necessary in order to move the debris forward and keep the mission in the same position relative to the debris (Zuiani).

A net mechanism could be used. This would consist of four mass which will be shot out with a spring. The masses will pull the net out and surround the debris. The net size can be rather easily adjusted. This net is attached to a tether which is controllable using a reel and a motor. The net, once encompassing the debris, will close behind the target and tighten slightly. The object, now captured, will be slowed down and sent on a new travel path (Bischof).

Considerations for our project

For our purposes, the vaporization lasers, surface material, and streams of air are almost immediately out of consideration. We plan to create a software that will create a travel path to the debris, so these capture mechanisms would not be of use to us. A solar sail can also be put aside as the concerns for this mechanism seem to be too technical for us to investigate. The amount of drag produced by solar photons may be near impossible for us to learn and estimate in the time needed. This leaves the tethers, ion beams, and nets. The tether seems to be the most popular mechanism used in space debris missions. The electrodynamic tether may be much more efficient than the momentum exchange tether, as the momentum exchange tether requires more control. The net seems a bit difficult to execute, as the encompassing and closing of the object requires even more control than the tether. The ion beam may require less control, and it seems to be the simplest solution. Still, the other options have not been ruled out and a discussion with the group may help produce a more informed decision.

References

B. W. Barbee, S. Alfano, E. Pinon, K. Gold and D. Gaylor, ”Design of Spacecraft Missions to Remove Multiple Orbital Debris Objects”, IEEE, USA, 2012

Bischof, Visentin, Starke, Guenther, Foth, Kerstein, Oesterlin, Ebert, Macaire, Wegener, Krag, Oswald, Lampariello, Agrawal, Nimelman, Ilzkovitz, Ashford, and Yoshida. "ROGER Executive Summary." European Space Agency. EADS, 10 June 2003. Web. 5 Mar. 2017. https://gsp.esa.int/documents/10192/43064675/C15706ExS.pdf/18bb5154-fa12-44f0-a240-d84672ac49d5

"e.Deorbit." European Space Agency. European Space Agency, 12 Apr. 2016. Web. 12 Feb. 2017. http://www.esa.int/Our_Activities/Space_Engineering_Technology/Clean_Space/e.Deorbit

David, Leonard . "How Huffing and Puffing Could Remove Space Junk." Space.com. N.p., 5 Apr. 2012. Web. 05 Mar. 2017. http://www.space.com/15178-space-junk-removal-spade.html

"Japanese H-II Transfer Vehicle Kounotori 6 fails to deploy magnetic tether to clear junk in earth orbit" Tech2. TechFirstpost, 07 Feb. 2017. Web. 12 Feb. 2017. http://tech.firstpost.com/news-analysis/japanese-h-ii-transfer-vehicle-kounotori-6-fails-to-deploy-magnetic-tether-to-clear-junk-in-earth-orbit-361268.html

"JAXA is going to test removing orbital debris in collaboration with a company that makes fishing nets." Tech2. TechFirstpost, 05 Dec. 2016. Web. 12 Feb. 2017. http://tech.firstpost.com/news-analysis/jaxa-is-going-to-test-removing-orbital-debris-in-collaboration-with-a-company-that-makes-fishing-nets-351294.html

"Orbital Debris Remediation." NASA. NASA, n.d. Web. 12 Feb. 2017. https://www.orbitaldebris.jsc.nasa.gov/remediation/

"RemoveDebris: Experiments." Surrey Space Center. University of Surrey, n.d. Web. 21 Feb. 2017. http://www.surrey.ac.uk/ssc/research/space_vehicle_control/removedebris/experiments/

Zuiani F., Vasile M. Preliminary Design of Debris Removal Missions by Means of Simplified Models for Low-Thrust, Many-Revolution Transfers. International Journal of Aerospace Engineering, Volume 2012 (2012), Article ID 836250