AngelLestat

I follow this model:

why this is in science section?

Ok, so EDF means electric ducted fans. I am really bad with acronyms. Now this has a lot more sense. Thrust control with electric motors is a lot easier than with turbines. About the efficiency lost when front and back fans are in horizontal, maybe if the back fans increase the rotation speed using a Frequency Inverter then the energy lost may be redundant. Yeah, a batterty backup would be very usefull, maybe with just 5 or 10 min would be enoght without add a lot of weight. This also saves as you said any problem in cases of extra thrust needed reducing the need of a big generator. with a lot of imagination... maybe

Ok, you are right, they use the same engines to produce the turn, here I find a video that show this with "more detail". But is still unclear how they pass fuel and energy across this complex joint which still needs to support all those tons. additionally, if the front engines and back engines are horizontal, the back engines receive the hot air and propulsion from the front engines. So how that can work? I dint find their page, can you post it so I can try to understand better?

Nice to hear that you wrote your master about this. There is another way to do it as this video show, but instead use a returning payload as energy exchange, This concept use the electrodynamic tether effect to recover the energy lost in the tether. http://www.nasaspaceflight.com/_docs/MXER%20TAG%202003%20Report.pdf

ok, I dont know how I miss read a V by a W. heh, agree.

someone understand how those engines rotate from vertical to horizontal? The engine support is too thin, I cant not understand how this design can work.. I guess VV should go back to cars. About the Aeros blimp, that is a clever design than probably would leave the prototype stage.

These are not venus problems: -levels of co2, H2SO4 and other similar components. -venus-sun distance. The only problem of venus is the total amount of H2, it has 10000 times less water than earth. Venus rotation may be a big problem too if you plan a full terraforming process. About the graphene o2 ballons idea may work if these considerations are taking into account: Ballons needs to have some coating protection against h2so4 and UV light, this may be done using some elements from the atmosphere (but they would not last much, is possible that after some years would need to be coated again), the other solution is to use metals from the surfuce as coating, platinum or tantalum would be permanent. Of course the graphene O2 ballons would remain very high, where the temperature is low (this reduce by a lot the h2so4 corrotion) In case we use tantalum or platinum as coating , the extra ballon reflectivity would increase the colling ratio of the atmosphere. Of course even without reflective coating, the atmosphere would cool too, just because we are reducing the atmosphere density by just trapping o2 and let the remaning carbon to fall to the surface. So if atmosphere density decrease adding these ballons, then their floating altitude would start to fall in similar ratio than the temperature does. They would start at 100km height at -80Celcius degree, then after a while they may be at 10km height at 0 Celcius degree. It would come a point where the ballons would touch surface, the o2 would be release, and we end with a planet of O2 atmosphere and earth like temperatures. (the lack of water or other greenhouse gases keeps venus temperature similar even being more close to sun) But the venus rotation and lack of water problem remains. Then we have another issue, Venus has heavier components than earth, that means extra radioactive elements in its core. This mean extra volcanic activity which may revert all the process before being completed.

yeah... this topic needs more serious people or it would not go anywhere.

yeah, that is why we are doing this research, so we can compare with real numbers, but if we take into account the complexity of the micro gravity biologic experiments, it does not seems cheaper than the tether. You are right. So many times I discuss these effects using similar words, that I can not believe I total pass over it here. Yeah, I am very familiar with the heat pipe technology. But my question was in case we measure in space that is heating up over our estimation levels, what can we do? Shutdown some systems? Yeah, that would be great. This would save us from the "crossing fingers" method. this cost is more than I expected for only one of many test. I sympathize with your professor feeling in that moment. I was thinking in permanent magnets (like a compass in equatorial orbit), but I dont know if this would be enoght in case the starting cubesat spin were too fast. My other concern is how to guarantee if the tether would deploy in earth direction or towards outer space, this has implications in the thermal shielding design and to chose the camera location. My question was related to the cost of the chosen altitude, what is the difference bettwenn 300 km or 700 km. The only things that I know is that at higher altitudes the lifespan as "future debris" of the cubesat (without a deorbit plan) increase exponentially, and I am not sure if that has an extra cost penalty. ---------------------------------------------------------------------------------------- I was making some research: The TetherSim software cost is: 5000 U$S http://www.tethers.com/tethersim.html Robert Hoyt told me that he provided some licenses to a few universities in the past. But for ITAR rules he can not give license to outsiders (that was for my case). So is still not sure yet if we can reach an agreement to avoid part of the cost. But he was very polite with all the info that he give to me. I read a paper which compare the lifespan of a single tether (in different diameters and long) vs a double tether in space. A single tether lifespan can round (in our case) between 15 days to 3 month. That is not enoght, a double tether on the other hand may last several years. Other concern is the chosen orbit, the EDT effect is higher in equatorial orbits, for example an orbit of 75 degress with respect equatorial would have an efficiency 70% lower. But the chosen orbit has effects in the power transmission needed to comunicate with the probe. If I find time, I would try to complete the budget for all components on the electrodynamic tether case.

so this add 60 parts to the menu selection? That is close to the stock number of parts If we want to add extra mods the game would take several min to load and increase the crash chance due to memory. ---------------------------------- Edit: I read that the scales can be done by tweaking. This is mean less parts in the menu selection and less memory dont you? I would test it...

Wow, these robotic parts seems a lot more usefull than infernal robotic, but I always hate the amount of parts that infernal robotics adds in the part selection menu, now they fix that with tweaking. What about this mod? How much parts adds into the menu parts? I would love to see only usefull parts with tweaking scales in case is not done yet. Great work.

Hi Ksat, is good to have someone with experience and knowledge in the field to guide us. If we find that in fact some components are overheating, what we can do about it? We can not use radiators or insultation if we dont have some attitude control with respect the sun. Any good insultator would be a bad radiator and vice versa. I know that this is not a easy question, but maybe there is some base designs to help us deal with this without much knowledge in thermal engineering. I dint, thanks. There is a doubt that I have with respect to this. I saw many videos where cubesats are inspected in special facilities which commonly work for the launch provider. You have an idea or estimate of this inspection and testing cost? Yes, we can keep our cubesat-tether normal to earth surface, but I am not sure yet how control the spin on that axis. I will make a research to know if there is another passive way to achieve that. Then know how to distribute the electronic load-shield is simplified. This altitude difference may increase the launching cost mostly due to possible lifespan as debris in case the tether system fails? Yeah,I will try to contact anyone who is studying this, I know that there is already software simulation to calculate space tethers, I will ask how much they cost or if there is a free version to students. Also there is the Nasa issue with this experiment, when apparently they receive a voltage peak out of their predictions. You would use some kind of tether (or the same conection wires) to increase the long and quality of the gravity simulation? Because if you dont do it, the gravity in the plant root would be higher than the plant top. You plan to use solar light to the plant growth or artificial? Because the intermittence due to rotation can be an issue too. That is something that we need to ask to Mary Musgrave. The plant species chosen, the time needed to growth, the light and conditions needed. All cubesat components depends on that. I know what you mean, but so many variables needs to fix and so few liquids to choose. The positive side is that it would not take you long time to know it. You mean test the sealed that you would use with higher pressure inside to mimic the pressure difference in space? As I comment in my first post, this would be an option only if launch cost fall at least 5 times or more before try to do an interplanetary mission, If this happen cubesats components cost would fall too. What post are you talking about? You mean use orbiter as simulator? Is not a bad idea, but the cost growth significantly, the space is also an issue, how much the plants needs to growth? ------------------------------------------------------------------------------------------------- I guess we should made teams to research and give an estimation of the components/cost needed, to evaluate different mission requirements. We can do it making extra topics, maybe new KSP field specialist will joint us. For example I will study the electrodynamic tether approach. Who want to help me in the research? Then K2 and others can team up to study the biologic microgravity approach. Extra teams can joint to study different approachs. Then we go back here with numbers, good estimations and more knowledge about the experiments to compare our options. Then it would be easy to see what approach we may discard or look with more attention. Once funds are collected. We do a final choice.

Hi Ksat, any advice that you can give us would be very welcome. Thanks for your time. I guess K2 is the right guy to give you a summary of the main ideas. The idea most studied so far would be plants growth in microgravity environment. Following the Mary Musgrave´s reasearch. http://today.uconn.edu/blog/2009/08/the-effects-of-gravity-on-plant-growth-and-development/ K2 or other forum fellow can give you more details over this. My concern and personal question would be this: What you would recomend as our first mission? For example I was look at the possibility to use a smartphone to cut expenses. It would be advisable with a mission lifespan not longer than a month? What are your thoughts about Electrodynamic Tethers? If we rely on this paper: http://enu.kz/repository/2010/AIAA-2010-8844.pdf Maybe we can test a 2U 1600m tether (total 1,1kg for all tether components and systems) or 1U (with shorted tether) to test this technology as propulsion system, gravity gradient and energy harvesting.

So anyone has an idea of the possible total cost? I guess you should compare all ideas with a list of components, mission objectives and cost of each part (showing sources if its has). With an average aproximation of space lifetime of each part. That is a required step before choose an idea and enter in a deep mission design step When the mission design is finish, only then we can create the kickstarter campaign and advertise the project to get extra funds.

from 4 min to 30 there is a big difference. Of course is not impossible, I just said very hard. It also matters how small is your sky view (second-min-degree arc), If we are using our mount just to place our DSR camera with a 50mm lens, then it is easier to get long exposures. For example, we already did the room building where it will be located the telescope, it only need the dome. But to place the telescope, we can not use the same floor, we need to use extra iron beams to the walls, to not transmit vibes into the telescope. therefore any tracking equipment handmade, needs to be robust enough to avoid any miss movement under the exposure. The most important is to possitioning the mount to the perfect north-south respectively. Post software edition helps a lot.

I have 2 telescopes, and in few months we would start to build our observatory. 30 min tracking?? You mean just follow a star or planet, or take a picture with 30 min of exposure? If there is the second case, you dont have idea how hard is that. Even 5 min sharped picture is hard.

I help to my brother once to make an assembler code to measure and storage wind speed data from an anemometer. At the begining all seems simple, we made the code, we test it, it works. Then we install the devide for 2 month in the study location. When we look in the data later, we notice that the data was discrete with jumps between values. It was something that we dint have into account in the code development. Similar things like this happen all the time in all kind of projects. Use already test it software saves time and reduce the chance of failures. A temperature sensor may not be complicate. But a CCD integration, accelerometer or other kinds of devices may not be so easier to code the current plugin. I find some software in internet for some cubesats cpu. But there are few, and they work only with their special hardware. We are not a whole university with lot of students, each working hard in their specialty with one goal and teachers as guide. You know me, I am an optimistic. But we need to stop make this project harder than already is. We can measure the cellphone temperature battery using the temperature sensor already located in the smartphone (if it has), if the battery warm, the phone would warm too. But if this happen, it will not matter what kind of battery we use, there is nothing that we can do about it. So what is your idea? What do you propose as mission? I know that you really want to leave the earth influence to go somewhere. But think about it. That is way far of our limits. If the launching cost drops significantly, then cubesats parts cost would follow too. Then that possibility may be taken (of course with a high chance of failure, Either way, it's going to be one hell of a ride) I have understand that any cubesat before launch it needs to be inspected by a specialized center. I guess they had vaccum test and other things. I dont know would be the cost (if it has). About shielding, the only that comes to my mind is these CNT sheets that are used to shield against magnetic interference. Something that is not needed in these circustances. http://www.raytheon.com/newsroom/technology_today/2012_i1/nano.html Any approach that we want fallow, it will be highly recomend to talk with people who highly knows these stuff first.I am not against this idea, but we need to avoid use any kind of inflatable device. The risk of lose pressure due to a fail in the sealed or being hole by a micro debris is high. Composite Fabrics that Nasa use are not easy to get. But if you said a tether that sepate a 2U cubesats in 2, to spin and give low gravity, then it can be done. (in fact it was done before, was called "SporeSat, 3U CubeSat") --------------------------------------------------------------------------------------------------------- Look the price of the CPU without memory or any other needed device: http://www.cubesatshop.com/index.php?option=com_virtuemart&Itemid=75 The prices goes from 5000 euros to 45000 euros. The one of 45000 has similar capabilities of any smartphone, it can have 2 camera and some sensors. Sorry, but I need to insist. Smartphones are the way to go. We can ask for recomendations to experience people to decide.

dharak1´s point was that the cubesat regular batteries are already insulated.. This mean ten meters of water too? Please... I work making software.And I tell you, the time that it would take to develope each piece of software to control all, is a lot. But if you want to do this project alone, why you did a topic about that? If you are the only with experience in MCU then is all on you. The main advice that NASA give us in the smartphone use, is the money and time that you can save in software development.

http://www.extremetech.com/extreme/98063-how-to-build-your-own-gps-receiver http://lifehacker.com/build-your-own-gps-car-tracking-system-1476721470 You know what else is not trivial? Try to interconnect different devices without future problems and develop their software to work all in synchrony in plattaforms that not everybody knows. Ok, I dint know that, but in the gps wiki page said: These limits only apply to units exported from (or which have components exported from) the USA – there is a growing trade in various components, including GPS units, supplied by other countries, which are expressly sold as ITAR-free. Only 2 grands? ah ok. give me 4.. XD (try to noy use acronyms, not everybody here knows english so well) Its ok to get funds to accomplish our objetives, but drop away the money that we can gather in silly things that we dont really need (or you plan a 4 years mission?) is an insult to the people who gives us money. Why you can not shield or insultate the whole smartphone? The 3 phonesats 1.0 cost $3500 each, and the phonesats 2.0 cost $7000 (the whole satellite). If you try to achieve the same functionality with regular cubesats components you end with $30000 each. The lifetime was 1 year, when it start to reboot it self (occasionally) after several solar flares. I dont have any info of any shield used on these phones. Five phonestats were already sent to space by NASA, strand-1 mission would test the smartphone use with fully understanding. It would have extra computers and sensors to corraborate data with the smartphone sensors. Many other missions are comming, these missions would give us a lot of info to make a good choice in this matter. Is a huge money difference that we are talking about. And test already done seems promissings. He dint prove it. It all depends on our lifespan mission expectatives. How evidence show, none of the already phonesats launched had problems in their lifetime, only 1 after 1 year of use. They had also bluetooth, that can be used to connect with other devices. And you are underestimating the time that it takes develop all the software that you would need. There is a lot of research to be done even with the low requirements missions, if you need to add the construction and software development, then it would take several years to finish the project, so it would be abandoned. I can help in research, some software development, maybe a dynamic webpage where everyone can see the progress of the mission, or maybe to command the cubesat from there. But we need to try choose a short lifetime mission to cut expenses and mission budget.

You know how GPS system works?? You just need to know the time, position of each satellite, then with an antenna you recieve signals of 3 or more satellites, using Einstein formules, you calculate your position and altiture. Then speed and other values are derivative of multiple measures. Anyone with electronic knowledge and software can develpe their own gps without restrictions. If someone can develope a intercontinental missiles, then it can develope their own gps!! For that reason after some time, the only restriction (10 m on accuracy, there was not altitude restriction) was eliminate from commercial devices.

those answer are wrong. GPS home system, low time ago, they had a restriction of 10 m on accuracy, that restriction now is out. Thats it! There is no more lock. http://www.nasa.gov/centers/ames/engineering/projects/phonesat2.html#.U8f0kvmSzwA

Why it would stop working? In any case that the gps software is not prepared to deal with those numbers, you just need to mod the software..

Why not? many are doing it. http://www.csmonitor.com/Science/2013/1120/Satellites-controlled-by-a-smart-phone-Tiny-CubeSats-reach-space http://news.techeye.net/science/nasa-puts-three-more-smartphones-in-orbit http://www.engadget.com/2013/02/26/google-nexus-one-launched-into-space-cubesat-phonesat-strand-1/ http://sen.com/phillip-keane/5-new-cubesats-successfully-launched-on-falcon-9 http://www.spacenews.com/article/smartphone-powered-cubesats-fly-antares-maiden-launch Tell me the difference between a smartphone battery and a cubesat battery. What are the chance difference to get a fail in the first day using a smartphone vs a cubesat CPU? smartphones electronics may had 0,01% of chance to fail vs a 0,0001% from a standard cubesat CPU? What really matters is how big your lifespan expectation are. If we keep our expectation low (short mission). Then we can save a lot of money. Smarphones were not used before just because the smartphone boom was in these last 3 years. PD: I forget a extra use for smartphones... They had GPS!! In low orbit GPS work as well as in surface!

That answer is for me? So what are you saying? that we need to have 2 cpu in a cubesats the same as one billion satellite? Or that CPU in sale for cubesats has an special electronic or shield to survive the space? They might be better prepared to deal with those conditions, but you can shield a smartphone too. If we reduce the lifespan expectations of our mission, then all became more easy and cheap to achieve. The use of smartphones is not my idea, as I said, many agencies or groups are starting to use them for their missions.