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Leonardo Times MARCH 2014SPACE TOURISM
SXC, one of the major players in the space tourism market, is actively selling space tickets. SXC is also allowing future clients a chance in their space travel simulator ‘Desdemona’. This simulator, located at a TNO research institute near Utrecht, is ca-pable of mimicking the physical phenom-ena that act on a human body during the launch of SXC’s space vehicle, the ‘Lynx’ [Figure 1]. Future astronauts are subject to 3G during a re-entry phase, and using smart disorientation tricks the simulator can re-create the feeling of zero gravity. Together with several other future as-tronauts I was allowed training for a po-tential trip into space. As part of a prize I won in February 2013 at a technology convention in Eindhoven I was allowed to participate in a full-day operation where we could experience what is was like to be launched to 100km, and how it felt to plunge back through the atmosphere.
(DIS)ORIENTATION
The day started with a detailed lecture on the exact workings of a simulator. Af-ter seeing the simulator do a trial run to warm up the systems we were ready to try it ourselves, but first a fundamental basis was created to prepare us for the
actual experience. After all, a simulator is made to reproduce the forces on a body, and in order to do that the mind has to be tricked. A centrifugal motion can be felt as an acceleration of the space ship in forward direction, as long as the brain is made to feel so.
During the lectures, we were introduced to the three most important attitude- and acceleration-sensing systems inside a hu-man body: the inner ear, the eyes and the “sixth sense”, a gut feeling that can be at-tributed to the sensory systems spread throughout the body. While the first two are well known, the final sense is mostly relevant to people experiencing extreme disorienting movements, such as a jet fighter pilot. The interaction and coop-eration of these senses allows us to deter-mine our movements with respect to the earth’s reference frame.
Should these sensory systems disagree with each other, the mind has to deter-mine what is correct and what not. An example of this disagreement is reading a book in a car: while your eyes only ob-serve no movement, your gut feeling and inner ears do register the car movement. As a consequence, disorientation sets in and people become nauseous. Another case is the moment you are sitting in a
stationary train, and the train next to you departs slowly. Purely based on your eyes it may seem as if you are moving, while the other train is stationary, creating con-fusion between your sensory organs as the remaining systems do not detect the movement.
This theory would become relevant later in the simulator. Since the simulator is spinning continuously to create a feeling of accelerations your actual movements do not align with your expected move-ment, and shaking your head results in a different inner-ear feeling than you would expect. Hence the advice: keep your head still at all times!
To put the theoretical knowledge to the test, and show how senses could be fooled by the Desdemona, all candidates had to perform simple task of walking through a hallway, turning a corner and opening a door. The only modification is that we had to look through a special prism that inverted the eyesight, meaning that turn-ing your head to the right looked like your head turned left. In other words, your in-ner ear canal started to disagree with your visual observations, leading to hilarious moments. People twisted the wrong di-rection, stared at the wall for minutes and could not find the door knob.
Training for space flight in a 3g motion simulator
On October 5, 2013, Marijn Wouters and two other contestants of a nation-wide
competition ‘Nederland Innoveert’ underwent a space training exercise. One by
one, the trainees were pushed to their limits in the Desdemona motion simulator,
an experience that mimicked the Space Expedition Corporation (SXC) space flight
envelope. The ultimate goal: training for an actual mission, the 1
stprize in the
aforementioned competition.
TEXT Marijn Wouters, MSc Student Aerospace Engineering, Aerodynamics
DESDEMONA AND A TICKET TO SPACE
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MARCH 2014 Leonardo Times
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Adapting to such a changed ‘orientation’ takes most people up to 8 days, and re-verting back to a regular condition takes an equal amount of time. An example was given by our instructor, describing an ex-periment where candidates had to play table tennis using the ‘inverted’ glasses. After a while, the candidates in the ex-periment were unable to play table ten-nis without the glasses, since they were adapted to their inverted vision.
UP, UP AND AWAY
After an informative morning it was time for the actual training. One by one the candidates were placed in the Desdemo-na simulator to undertake a virtual trip to space, while the other candidates could enjoy the view from inside the control room. After the fi rst candidate had suc-cessfully made it back to earth, it was my turn to step up to the walkway.
Stepping in the simulator felt a little like climbing on to the platform of the Apollo rockets: a retractable walkway, a huge mechanical device, a fl ight suit and a tiny cabin to sit in. After I am securely strapped into the seat, I could only communicate to Harry van Hulten, test pilot and COO of SXC. From the control room the whole conversation could be monitored by the others. “Are you ready, Marijn? On my count, press the red button on the con-trols”.
The simulator is fi rst moved into position, and slowly starts to rotate. Surprisingly, the movement does not make you nau-seous in any way. The virtual Lynx slowly turns onto the runway in simulated Cura-cao; even the bumps in the pavement are mimicked by Desdemona.
“3… 2… 1… ignition!” With a jolt the sim-ulator springs to life and accelerates its ro-tation, and in the cockpit I experiences 2g as the Lynx accelerates. It is an enormous rush, and the experience is highly immer-sive as every bump in the take-off strip is felt. Once the launcher reaches suffi cient velocity it takes off , and the initial rock-ets are extinguished. I can’t help smiling: the simulator is fully drawing me in and it feels like the real deal! After a few seconds, I can push the red button again to start the fi nal ascent to space.
After pressing the button again, the rock-et fi res, quickly accelerating the vessel to Mach 2 as the trajectory slowly turns verti-cal. The sensation is phenomenal, and the simulator creates an eerie sense of actual lift-off . The initial acceleration starts to lessen, but the vessel is still gaining speed as it is propelled into the sky. After what seems like minutes the g-forces start to reduce as the blue sky starts to shift to a black, star-spotted vista. Slowly I can start to relax as the accelerations seem to van-ish, and the simulator performs another trick.
By tilting forward and drastically reduc-ing rotation, a feelreduc-ing of weightlessness is created, a very confusing feeling after experiencing heavy acceleration only seconds before. The sensation of ‘micro-gravity’ in magnifi ed by the amazing view through the ‘cockpit’ of the Lynx. As the Lynx slowly tilts forward the Earth comes into view, revealing an amazing scene and actual sense of altitude. Harry starts point-ing out various landmarks as I take control of the simulator using the internal steer-ing column. In micro-gravity the occupant is able to control the spacecraft attitude, something that felt like a cross between a
computer game and driving a car. Quickly I take in as much as I can of the surround-ings, since I’ll only have a few minutes to appreciate the view before I plunge back to Earth. Seeing everything from up high makes me wonder how it would be like to be in the ISS, and experience this view every day.
Before long, the simulator takes over and I have to prepare for the hardest part of the simulation: the 3g re-entry phase. For 20 seconds the simulator spins in a mad rush, and I can only laugh; it is an amaz-ing feelamaz-ing! I had imagined it as an annoy-ing, constricting feelannoy-ing, but it closely re-sembles a very intense roller-coaster ride. As instructed I tighten my leg- and lower body muscles to restrict the blood fl ow to the upper part of my body, ensuring that a lack of blood fl ow won’t cause me to pass out. The sensation is incredible, and I be-gin to understand the term “g-junky” that was mentioned by the SXC personnel. After the pull-out manoeuvre a gliding fl ight back to Curacao off ers a chance to relax and enjoy the last moments in the simulator. It was an amazing feeling to ex-perience the simulator run, and what it felt like to be propelled into space. Without a doubt it was one of my best aerospace-related experiences so far (including the Aerospace faculty parabolic fl ights), and it leaves a hunger for more!
Time to experience the real deal.
References
Desdemona simulator: http://www. desdemona.eu/
Space Expedition Corporation: http:// www.spacexc.com/en/home/ Figure 1. Lynx space plane
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