Looking Back

TED Talk Rehearsal Video

Now that the TED Talks are over, this project has come to an end. I enjoyed working on this project and learned a lot about the space program and of many cool concepts for future space exploration. I appreciated being able to have my own ideas and especially liked learning that they have practical applications, as when I started this project and throughout working on it I was expecting them to be impractical, expensive, and really only useful to the space program. Despite that even something as expensive and large scale as a space elevator could have many practical uses, which surprised me. I also appreciated being able to work with an actual NASA engineer on this project, it was certainly a pretty cool opportunity for a junior in high school and could even help me get into the space program more easily in the future.

That’s kind of a jumble of words over what I enjoyed throughout the project. To better sum it up, I learned a lot about things I was interested in, got in contact with people who could help me along in my career, and got a taste of what I might end up doing as a career. It was great to be able to do what I care about at school especially since I rarely ever get that chance, and I probably would have never done something like this on my own time.

Though if I could go back and change the project a bit, I certainly would have stayed with the same topic, but I might have done more research in to more practical, or at least less expensive ideas. The rover design didn’t have this problem, and if they wanted to NASA could probably use those ideas on a rover, but the space elevator isn’t so realistic. I doubt anyone will hear about a space elevator actually being made in this century, I love the concept and enjoyed designing one, but for this project something more modern might have been needed.

Overall I really appreciated this as an opportunity, and would like to see something like this implemented in school far more often.

A Job Left Unfinished

When it comes to designing things in engineering, normally many more ideas are considered than ever go anywhere near reality. Whether that be because they were ridiculous or simply because there isn’t enough time, most ideas will never see the light of day. In my case, I’m both out of time and out of good ideas. There’s many things I could look into for rover design, such as more advanced materials to make it out of for it to survive harsher climates (such as the ice caps on mars), extra science parts that might be useful on it, and maybe even something like attaching a balloon and small rockets for it to get across large gaps. Despite that, I’ve still produced some decent concepts and will be able to submit those for review.

Working on the rover was interesting, as it was more coming up with my own ideas than the elevator. The elevator was a project of finding people’s good ideas and combining them to make an ideal space elevator, though I did still add in a couple of my own designs for it. The rover was much more so about thinking of what could drastically improve rovers, and because it was centered around future designs I was able to get a bit more creative. Now that it’s getting closer though, its time I start thinking about how I will do my TED talk. I’ll probably just review the directions the project took, the process used for designing things, of course go over what I actually did accomplish, and finally just talk about what I learned and the applications of that for the future.

 

An Ideal Metal

I left off last week on the topic of finding a metal ideal for a future rover’s wheels. Now, it would be nice if I could just say we need a very strong metal, choose something like titanium and just roll with that. However, as is the standard with space engineering, it is not that easy. Aluminum is used heavily in space craft as well as rovers due to how lightweight is and its malleability which allows for it to be molded into much tougher shapes. Despite how useful those characteristics make aluminum rover wheels made of it simply can’t last for long periods of time. Most of the time it lasts years beyond expected mission time (as most spacecraft of all kinds do) though when it comes to a rover that is meant to be extremely mobile and resilient everything is going to be more expensive and as such it will be expected to last longer, so wheels will need to meet that standard. There’s a few different ways to go about finding the ideal metal, aluminum alloys could be made so it is stronger and more resistant to damage while still retaining at least some of its characteristics. Simply using heavier stronger metals is another option, but there is always the need to balance out weight and strength, they can’t add too much weight because that might end up getting the rover stuck in sand, not even mentioning the extra cost that weight will add at launch. Then there is the possibility of new metals being created, for instance a very strong metal was created at UCLA in 2015 made of magnesium and silicon and many uses for it in spacecraft and planes are already being considered. A unique metal such as that would be ideal for rover wheels and possibly other parts depending on how expensive it is and how much of it can be created. The best choice for the wheels depends on how heavy the rover already is, and what new metals have been created by the time a new rover is made. There is still more that needs to be looked into, though.

Reinventing The Wheel

 

When it comes to designing a rover that can overcome the challenges faced by past rovers, it’s definitely going to be expensive. I’m bringing this up because one significant cost of my design would be the wheels. Curiosity’s wheels are made of aluminum, and aluminium is an excellent choice for wheel design because it is light and can be molded for more strength and structure. The problem is that it wears down over time from continued use, so much so that wheel damage is currently the biggest threat to the Curiosity mission, and it shows through the large hole in the wheel above. If someone were to make a rover that is vastly more efficient than other rovers having wheels that wear with time would be unacceptable. The solution to this is to use heavier metals, but this comes at a cost. First off, heavier metals are simply more expensive and more difficult to easily mold into shape. But the more significant costs come from the extra weight they would put on the rover, with launches small amounts of extra weight can add millions to cost. Much more durable wheels make up for their consequences though. They’d allow the rover to go very long distances without concern of the wheels wearing down significantly as a result of continued use, difficult terrain, and possibly cliff falls. The problem is figuring out exactly what metal would be ideal, but that is next week’s problem.

Parting From Traditional Design

Last week I talked about designing a rover. This week is when I actually will get started on doing that. My current idea is to have a rover that can be flipped over without consequence. Having this ability would ensure we could give commands to rovers to travel long distances without having to worry about it flipping over due to a rock in the way. The way I’m wanting to achieve this is by having the main body be smaller than the wheels and having all science parts built into the main body, and have specific parts be retractable. To further save space a piston could be attached to the body to flip the rover over, and different science parts could be attached to each side of the body so we could flip it over to use different parts. Ideally more parts would be built into the body and could be used without any special procedure, as complex mechanisms that move parts up and down are a liability if they break, but some parts like a camera would have to be retractable. As for construction standard parts and materials would work fine for this design, as this is meant to go on Mars, though some changes might be made such as the wheels (more on that later). The final product would probably look pretty interesting, because as you can see by the curiosity diagram above, there are a lot of science parts that would be needed. Despite that it’s certainly possible, though having such a design may cost more in the long run and be more difficult to launch, the massive gains possible through it could make it worth the consequences.

That’s the first part of the design, and it certainly helps a great deal to make a more mobile, durable rover. Still, more has to be done. What if the rover falls a short distance and is rendered completely unusable as a result? What if one of the tires is broken in some way? Problems like that are why we are so cautious when sending rovers commands, but installing fail safes for things like cliffs or eliminating the possibility of critical parts like tires breaking down at all would make the rover far more reliable and efficient than anything we’ve ever had before, but that’s something I’ll be looking into next week.

The Rover Of Tomorrow

Rovers are at the forefront of Martian exploration, since the Sojourner rover landed on Mars in 1997 several other rovers have been launched, and a mountain of scientific data and pictures has come from them all. In it’s lifetime Sojourner (the first NASA Mars rover) traveled around 100 meters in total, our progress since then can be seen by the Opportunity rover, which has traveled over 26 kilometers. Curiosity will likely surpass that, having reached 10 kilometers, but in one fourth the time. Despite that, there’s always room for improvement. Rovers are given specific commands on how far to drive, what tools to use, and whatever else a scientist on earth needs a rover to do. The reasoning for commanding them like this, instead of something like a remote control car, is that it takes 21 minutes max, 4 minutes minimum. We can’t give the rover’s very long commands in case they might get stuck on a rock or, god forbid, fall off a cliff, if that happens we won’t be able to cancel possibly devastating commands in time. Because of that, rovers are covering far less ground than they could. The solution is to have a rover that can be given commands to drive for long distances and for that happen it needs to be able to handle whatever obstacles it might come across, at least for long enough for new commands to be sent.

A rover that can handle anything it comes across (at least on the Martian surface) is what I am going to try to design in the new few weeks. I’ll be using Curiosity as a model for what science parts and other accessories need be on the rover, aside from that it likely won’t look very similar to rovers in the past. It will be an interesting challenge, and I’m curious what the end result will be, assuming I am even able to reach that point.

Wrapping Up The Space Elevator

Last week I went over the construction process and cable design for the space elevator, and I mentioned that the ability of graphene ribbons to conduct electricity would be an important part of the elevator climber (that’s the actual elevator part, and it is pictured above). Before that I need to clarify climber design though. There are a few basic principles behind the climber. First it needs to be able to withstand solar radiation, in all likelihood we wouldn’t need to design it very differently from the ISS in this regard that being standard spacecraft materials with an accompanying strong room made of a metal able to resist radiation such as lead or tungsten in case of strong solar flares to protect any people on board. It would also have to be relatively light as estimated travel times are already very long being around 5 days and weight would only increase that time. Finally, it would not be designed like a typical elevator as that simply isn’t practical, most designs have it using two pairs of wheels or rollers that will hold on to the cable using friction. Climber design is probably the simplest part of a space elevator, the only considerable challenge associated with it is how it would be powered. Solar panels have been proposed, though they would add considerably more weight to the climber, there’s also the far less plausible idea of storing the energy in the climber before it is sent up which is likely only possible through nuclear energy which is only likely to make life more difficult. The other idea is to have electricity produced on the ground and then sent up to the elevator. This is where graphene ribbons ability to conduct electricity comes into play, we could simply power the climber by sending electricity through the cable. The most commonly proposed design is wireless energy transfer where lasers are sent to something akin to solar panels, which is by far my favorite in concept because it sounds really awesome but that would add more weight to the climber. It could be useful down the line with mobile ocean platforms, as well as solar panels, as we need a source of power that is able to get power to the climber wherever it is. I prefer using graphene ribbons in my design because it is stationary and therefore electricity produced on the ground near the elevator is more effective.

The final part of my design is the counterweight. This depends on when we can actually build the elevator. If we were to build it relatively soon, let’s say in the next ten to fifteen years, something like capturing a large space rock, like an asteroid is the most realistic counterweight we could use. We would probably have a probe or manned rocket attach to the rock and move it into position to achieve this. If we take longer to get around to building it something like a space dock or station (pictured above) heavy enough to support the elevator might be realistic, and that’s what I would propose if it comes to that point.

This is probably the last blog I’ll be doing on space elevators; next week I’ll be working on all access mobility (which regards manned vehicle or rover designs). I’ll be submitting the designs of the elevator to my contact at NASA and any noteworthy feedback I get I’ll likely mention, but due to its complexity and large amount of resources needed for it, I certainly won’t see any work done on it this semester.

Expensive Materials With Odd Names, And How To Drop Them From Orbit

Last week I talked about space elevators, their design and some ideas I have for them. This week I’ll be continuing with that, going more in depth on specific design areas.

The most important part of the space elevator is its cable as it makes up a vast majority of the structure. The cable has to be remarkably strong, flexible, and light, being able to resist 4,960km of tension if the elevator is at sea level. For some context, Kevlar can only resist 400km of tension. So what’s the solution? If the material that stops bullets is literally miles away from what is needed, what will work? The answer is several materials that sound both extremely scientific and extremely expensive, such as carbon nanotubes, diamond Nano threads, and graphene ribbons. My number one candidate is graphene ribbons, which is predicted to be able to resist 5000-6000km of tension, while also being able to conduct electricity (which is very important, as the climbers that bring people and spacecraft up require a lot of electricity, though there are alternative options). Problem is all of these materials have yet to be produced in a length anywhere near what would be needed for a space elevator, but we also haven’t really had a need for them to be that long either.

The plan is then to have a stationary grounded space elevator, where a base (concept pictured above) would be built at high elevation on very stable ground, and the cable would attach to that base. Colorado is a pretty good candidate for this, many space companies monitor satellites and probes due to the stability of rock formations in the mountains, and of course we are all aware of Colorado’s high elevation. While this would put the elevator at risk of being hit by space debris as it won’t be able to maneuver out of the way, unlike seafaring space elevators, which could move more. However, a grounded space elevator will drastically reduce the tension the material will need to handle, giving us a safety bubble, and it will also make construction significantly easier, and as I have mentioned before that could be the biggest obstacle. That said, space debris does indeed prove a massive threat, a space elevator would easily be the most ambitious and quite possibly expensive engineering feat ever attempted, having any possibility of it being destroyed is a massive risk. The solution, is that once the first space elevator is built, the next one will be much easier to build, we will have learned how to build one and we would also be able to launch parts from one space elevator to the construction site of the other, which I would propose to be a sea faring type of elevator.

As for prepositions for construction, conventionally building from the ground up is pretty much out of the question. Most theories involve the cable falling from orbit. I agree that that is probably the best option, we’d just have to compress the cable enough so we could manage to launch it into space through conventional means, attach it to the counterweight, and then release the cable when it is above the anchor point on earth. Problem is how we would contain a cable around 30,000 km long in a package that can be launched. My current idea is to send it up in multiple coiled up packages, and connect them before dropping it down to earth.  It would take a lot of innovation on our part, as well as funding, but I certainly think it’s possible.

 

Changing Direction

Last week I said I’d be working on systems to detect space debris. This week, I’m going to be doing something completely different. The reason for this is that I had 2 contacts for the project, and the first responded last week. This week, my second contact responded, he’s working on NASA’s Orion project, which is a shuttle program which will be used for long range manned missions, such as Mars. He has a lot more potential than the last, as he gave me a lot more engineering specific problems and he is much more willing to work with me, and possibly even get funding (though, I doubt that will be needed). As I mentioned, he sent me a list of problems to choose from, and I chose the following:

• Economic Space Access, currently launching anything into space is extremely expensive, a way to drastically reduce this cost would be invaluable.
• All Access Mobility, which is to design a rover or manned vehicle that is significantly more mobile and versatile than what we’ve built in the past, as rovers have been very limited.
• Surviving Extreme Space Environments, which is to design equipment that can survive very harsh conditions, such as Venus
  

 

I’ve gotten started on economic space access, as I immediately got an idea for it. Space elevators have been a concept since the late 1800’s. Back then, they were pretty much self explanatory, just an elevator that can reach space. The theory has been heavily revised since then, it is now a system that can be used to launch spacecraft and satellite by simply dropping them in orbit, a massive counterweight is also present in the design, as it would give structure to the elevator, which would likely be made of a strong flexible material, such as carbon fiber. If this was created, launching spacecraft and satellites would go down from costing hundreds of millions of dollars, to only a few hundred dollars. This is going to take a lot of research, as there are a lot of factors that go into a space elevator. The first has to be the material composing most of it, it has to be remarkably strong and able to resist massive amounts of strain, while being flexible, carbon fiber is one such proposal, however diamond nanothreads are also a strong candidate. I’m looking at graphene ribbons most of all, which are just as strong as the other two candidates, but they can also conduct electricity, which is necessary to power the climber (but there are other options, like solar panels). The climber is what will carry spacecraft and people up, it can’t be designed like a typical elevator. I’ll have to design that at some point as well, but I haven’t started on it yet. Choosing a counterweight will be important too, it needs to be relatively heavy, proposals for it include capturing an asteroid or creating a very heavy space station. I’ll also need to decide whether I want the elevator to be stationary or on a mobile ocean platform (which works as the structure is supported exclusively by the counterweight, and as such won’t be heavy from the ground). The mobile platform could avoid space debris, and space debris could be problematic. A stationary platform would have a strong metallic base, instead of being made purely out of something like graphene ribbons or carbon fiber, which would heavily reduce the tension on the material (especially if it is built at a high elevation), increasing structural integrity, but it might be vulnerable to space debris. The largest challenge will be the construction process, which might be completely impossible through current means. 

You may be wondering why I’m working on a theory that seems to be relatively fleshed out already, why would I go about trying to design one when it seems other people already have? The idea is to possibly come up with ideas of my own, and unify all these theories and plans into one design. It’s definitely going to be an interesting few weeks, and I don’t think I’ll be changing direction this time.

Actually Solving Problems

As I mentioned last week, I’ve been talking to my contact on this project, but I was having issues getting specific problems to work on. Thankfully that problem has been fixed, and I’ve gotten several of them, which should keep me busy for a while. The problems I’ve been given are:

• How would you deal with a health condition of your choosing, in a longer mission?
• How would you design a work day to keep astronauts busy and psychologically stable?
• What would be an ideal design for a living space in a spacecraft meant for longer missions? Keep structure and functionality in mind.
• Design a warning system for a spacecraft leaving earth’s orbit to avoid debris, and design a system to detect space debris when outside of earth’s orbit.

The intention is not to complete all of these by the end of the semester, I’ll be starting with the ones I am most interested in and have the most experience with, and going down the line. I’ve already gotten started on the debris systems, as most of my background is in engineering. I’m currently working on ways to detect debris outside of earth’s orbit.

A bit of context is necessary first, though. NASA and a few other groups are already constantly monitoring debris around earth, due to the danger it poses to the international space station and active satellites. At the speeds everything is going at just to stay in orbit (on average most objects are going at around 16,000mph) any collisions can cause damage, even with something as small as a paint chip. That said, objects that small won’t cause massive damage, what they have done is cracked windows, but that isn’t enough to render anything inoperable, and windows are only present on manned spacecraft. The reason that a system to detect debris outside of earth’s orbit hasn’t been developed is that we’ve never sent any manned mission beyond earth and the moon, so we’ve always been able to easily track debris that might be harmful. Probes and satellites haven’t needed it, there isn’t much debris in space that we can’t see or aren’t actively tracking that could harm them, small objects like those that cracked windows aren’t very noteworthy concerns to them. But on a manned mission to Mars, that becomes an entirely different story. A broken window isn’t a terrible problem (none have been broken bad enough to create a significant vacuum) on a shuttle that’s going to return to earth soon anyway, but on a mission that’s supposed to last 2 years, it’s important to avoid all the debris that we can, even if we haven’t had as much problems in the past, because while all missions are worth many hundreds of millions of dollars, human lives at stake means we need to be much more careful.

Now that I’ve established the importance of being able to detect debris on a spacecraft, how am I actually going to design a system that can do that? My current idea is radar, where microwaves are sent out constantly and they’ll reflect off of any debris, allowing the pilot of the craft to maneuver out of the way if it is deemed harmful. Spacecraft have had radar systems on them before, Magellan (pictured above) for instance, used radar to map Venus’ surface, and did so from a maximum of 5,296 miles away, and that was in 1989. Magellan’s data was processed on earth though, which is fine for a satellite, but for a manned mission that will be going to Mars, where there is a 40 minute round trip time for signals sent out, this could prove problematic. The reason for that is that the craft will be going very fast on it’s way to Mars and the signal time will get progressively worse the farther it is away, so depending on the radar systems effective range (which I should add I’m still trying to figure out) the ship could be damaged before earth is even aware there is debris in the ship’s path. The solution to this is to put more advanced computer systems on the ship, which may very well be plausible today, but it would certainly add more weight, and that’s something that is often frowned upon when designing rockets and spacecraft, as weight starts adding up to many millions of dollars quickly. I’ll be looking into whether or not that will be a problem, as well as many other factors, like the accuracy of radar and how expensive it might be to have a radar system in the next few weeks.