Mars Co2 or other compressed Gas Hopper rocket

louis · 2019-03-31 07:08:41

I would have thought compressed gas rocketry would make much more sense on Mars for survey work. Think in terms of something like the lunar lander on a smaller scale. It has a PV array fan that generates the energy to compress the Mars atmosphere. Gas is released and it flies up and with rocket nozzles can accomplish lateral flight for a considerable distance. Takes photos and other survey info as it flies over . Then lands again. Repeats procedure. If it could cover a few kms each time this would be v. useful.

tahanson43206 · 2019-03-31 07:49:41

For Louis ...

Your suggestion here has a distinct advantage over helicopters which might be deployed on Mars! The envelope for payload, elevation, range and durability seem much greater. However, I have never heard of such a system having been developed on Earth.

Thus, the validity of your idea may be limited to Mars, where it might well turn out to be quite competitive.

That said, my guess is that the technology investment and mass requirement for a fully functional aerial exploration based upon your idea would be greater than was the case for the flight ready helicopter test article.

Would you be willing to do a bit of investigating, to see if anyone on Earth, at ANY time, has invested in a system as you described it?

If you find such a system, there should be records of success or failure, and we might be able to learn a bit about what problems the designers addressed.

Edit: Louis, to help you get started, here is a discussion of use of compressed air for rocket propulsion. Please note that your proposed system will include a pressure vessel, in addition to the compressed CO2, along with the mass of the vehicle strong enough to hold the pressure vessel, the gas, and the rocket plumbing and control systems. It would help if you can find a friend with the required technical expertise to help you develop your idea for the Mars environment. It might well prove to be competitive there.

https://engineering.stackexchange.com/q … -as-thrust

(th)

louis wrote:

I would have thought compressed gas rocketry would make much more sense on Mars for survey work. Think in terms of something like the lunar lander on a smaller scale. It has a PV array fan that generates the energy to compress the Mars atmosphere. Gas is released and it flies up and with rocket nozzles can accomplish lateral flight for a considerable distance. Takes photos and other survey info as it flies over . Then lands again. Repeats procedure. If it could cover a few kms each time this would be v. useful.

Last edited by tahanson43206 (2019-03-31 08:09:41)

SpaceNut · 2019-03-31 09:07:11

In the edit tahanson43206, you have given some of the extra mass to make an atmospheric hopper not possible with in the lift capability of the mars gravity well. So if we move the items that are not needed to fly then it becomes a bit more possible.
We also need to remember that a full tank will only use 50% to 70 % so as to leave retro propulsion capability to land back at the launch site.

Not needed in the flight
1 Compressor
2 full scale power from solar as once you launch the systems for control require by far less

changes to mass
1 pressure vessel to be made from composites

tahanson43206 · 2019-03-31 11:31:08

For SpaceNut #65 ....

Following up on your suggestion to build the pressure vessel for Louis' CO2 hopper out of composites ... The entire vehicle could (presumably) be made of ultra-light materials, which should help as well. Something to keep in mind is that a test article can be made and tested on Earth. The payload on Earth can be zero, because on Mars it will be equal to or greater than the mass of the vehicle and CO2 propellant.

However, a compressor and solar panel system will need to be shipped to Mars, so I presume your use of the word "flight" refers to the flight of the vehicle after arrival at Mars, and after the pressure vessel has been primed by the compressor. One significant difference between CO2 vehicle and the NASA test helicopter is that (as noted above) the potential lifting capability of the CO2 system is far greater.

The control electronics can (presumably) be supplied with electrical power from batteries, so that no solar panels would be needed on the vehicle itself. That said, a small solar panel might be considered necessary to insure emergency power to a small radio beacon, if the vehicle manages to exhaust itself before it returns to base.

Louis, if you can find a friend with the appropriate skillset, and another with the financial resources, you could (conceivably) see an Earth based test version of your idea flying within a year or two.

(th)

louis · 2019-03-31 15:26:55

This compressed air rocket, using water as a propellant, reached 850 metres' altitude. About 8 litres of fuel and propellant - just 1.5 litres of water.

https://www.youtube.com/watch?v=Tb5FVrEeE50

I think a Rocket Hopper using compressed gas and water could possibly work. The water would be extracted from the Mars atmosphere.

Some key issues would be:

1. What mass would be required to generate say 5 litres of water, extracted from the atmosphere. I seem to recall a NASA proposal for an 800 kg machine to produce 3 kgs of water per sol... that sort of mass relationship wouldn't work, I think.

There are mini dehumidifiers on sale. This one is less than 0.5 kg.

https://www.wayfair.co.uk/diy-plumbing/ … html?piid=

Basically I think you would be aiming for something that could produce say 5 litres over 10 sols - 0.5 litre per sol.

2. You would need to keep the load mass v. low I think. But Go Pro style cameras could be v. lightweight as would onboard coms and guidance.

3. The craft would need to have a lightweight PV array to provide power for air compression and water extraction.

4. Apart from cameras on board science survey equipment would be fairly limited.

SpaceNut · 2019-03-31 15:57:13

https://en.wikipedia.org/wiki/WaterRocket

https://www.instructables.com/id/Water- … sed-air-1/

https://www.instructables.com/id/Compre … le-Rocket/

https://makezine.com/2008/12/13/compressed-air-rocket/
https://cdn.makezine.com/make/2010/04/c … rocket.pdf

These designs all fall hard or use a parachute to land. Something that on Mars is not going to work. The suggested fuels of LO2 and LCo would be good enough but it comes with a power cost.

tahanson43206 · 2019-03-31 17:23:51

For Louis #5 above ...

Why have you given up so easily on your sensible idea of using compressed carbon dioxide to provide propulsion for a Mars vehicle?

Water is NOT readily available for use on Mars, and using it in the way you have described in #67 above seems (to me at least) wasteful.

On the other hand, CO2 (or specifically, Mars atmosphere) ** IS ** readily available, and it can be compressed over a number of Sols if necessary, to achieve the pressure needed for a particular mission.

In #68 above, SpaceNut has shown several examples of air pressure powered rockets. The Mars atmosphere vehicle would use the same principle, of course, but to be useful for more than an educational demonstration, it would need to be designed appropriately.

Please consider focus on the CO2 vehicle you have imagined.

By doing so, (it seems to me) you would bring value to the collection of knowledge accumulating in the NewMars forum database.

(th)

Last edited by tahanson43206 (2019-03-31 20:20:08)

SpaceNut · 2019-03-31 18:01:15

We know that with the thin mars air we need to compress it quite abit to be able to make use of it for other things and with it there is almost always a waste gas from the processes that we choose to use. That said we can reuse them since the energy investment has already been done. These will include some water, nitrogen, xenon, argon, methane, Co and maybe others to make use of over time.

Here is a related topic in Compressed gas energy storage

SpaceNut · 2019-03-31 19:57:37

Something I just thought of is that water will freeze in the rocket so now we will need to heat it, then will it freeze in the nozzle when it exits blocking the out going mars air.
Lots of things to think of in this design that can make or break it for sure.

tahanson43206 · 2019-03-31 20:19:28

For SpaceNut ...

Thanks for creating this new topic, and for showing the Compressed Gas discussion from 2014 (or so) ...

One of the points brought up in the Compressed Gas discussion was the need for all moisture to be removed from the gas, because of the drop in temperature as it is allowed to exhaust through nozzles for propulsion. You (of course) just remembered that point in #9 above.

Your showing us the 2014 thread is a reminder that topics that seem fresh to relative newcomers (like me) have often been thrashed out thoroughly in previous years.

However, setting aside the question of a gas pressure hopper for a moment, the point you made in the quote below seems worth noting. Compressed CO2 has been proposed multiple times (that I have seen and probably way more than that) for machine applications (tools, vehicles, etc). By any chance, has the optimum method of extracting various elements from the atmosphere of Mars been addressed previously?

If CO2 needs to be moisture free for machine use, it might as well be free of all other elements, which would mean that the CO2 production facility would be accumulating useful elements over time.

(th)

SpaceNut wrote:

We know that with the thin mars air we need to compress it quite abit to be able to make use of it for other things and with it there is almost always a waste gas from the processes that we choose to use. That said we can reuse them since the energy investment has already been done. These will include some water, nitrogen, xenon, argon, methane, Co and maybe others to make use of over time.
Here is a related topic in Compressed gas energy storage

SpaceNut · 2019-03-31 20:41:59

The Mars Homestead a project did lots of this type research. RobertDyck was a member early on.
https://www.co2captureproject.org/pdfs/ … ration.pdf

Here is the document page for the Mars Foundation
http://www.marshome.org/documents.php

Gas seperation membranes and temperature, will with compression do the trick....

Evaluation of Mars CO2 Capture and Gas Separation Technologies

tahanson43206 · 2019-03-31 21:18:37

For SpaceNut #11 ...

Found this in the marshome powerpoint:

Ok ... can't paste from PowerPoint ...

Slide 9 covers compression of Martian atmosphere to obtain various useful elements and compounds.

However, after looking at several of the links you've provided, and (in particular) noting the factor of having to cool compressed gas (air or other) for storage, it crossed my mind to wonder if the answer might be to NOT cool the compressed Mars atmosphere for a hopper, but instead to allow the heat to accumulate along with the molecules of gas.

There would be limits to this, of course, but perhaps there is a small range of applications for which it would make sense.

In one of the links you provided, the author pointed to the use of compressed carbon dioxide on Earth for carbonated drinks. This point came up in a discussion of the greater cost of compressed air as compared to compressed carbon dioxide.

In that particular document, the author asserted that carbon dioxide was kept at "low pressure" on Earth, compared to air.

Interesting! It turns out that compressed CO2 was used in paintball gaming. This link points to a discussion of pros and cons of using CO2 vs air for paint ball.

https://www.paintball-online.com/Compre … -s/684.htm

The points made about cooling of CO2 during expansion seem quite relevant to the Gas Hopper topic.

However, the paintball application suggests to me there may be other "Earthly" experiences with compressed CO2 that might be worth considering as the Mars application(s) are imagined.

(th)

tahanson43206 · 2019-04-01 08:59:15

This is for Louis ...

Would you be interested in serving as a Product Champion for a CO2 powered hopper for package delivery on Mars? The responsibility would involve recruiting team members with the requisite skills, experience and motivation to help with a not-for-profit undertaking, on behalf of the future residents of Mars.

What it WOULD require is persistence of vision, and patience to help team members through the inevitable bumps along the way.

What I would like to suggest is setting a reasonable goal for the capabilities of the vehicle, and a time frame.

As it happens, we are a few days into a New Year on Mars. If you set a target date of the next New Years, you ** should ** have time to persuade the team members to assist, and time for them to carry out the myriad subtasks that would be needed, in time for a physical demonstration on Earth.

I would like to suggest a simple goal for capability: Delivery of a hot pizza (in air tight package) over a distance of one kilometer, and return of the vehicle to the sending station. This would correspond (roughly) to the parameters we are anticipating in Sagan City (2018), where plots are a kilometer square.

Your design would (following your previously expressed preference) employ solar panels to deliver the energy need to compress Mars atmosphere.

Tradeoffs to be managed include determining what temperature of gas the tanks can hold, and what pressure can be held at the lowest possible mass penalty.

I will try to find an image of the Neil Armstrong Lunar Lander test vehicle, to show (in conceptual terms) what the vehicle might look like.

This is from wikimedia.org:

Here is a design suggestion that came from the paintball web site: To avoid potential problems with liquefaction of CO2 which may occur in pressure vessels, route the CO2 ** UP ** out of the tank, around and down to the exhaust nozzle.

(th)

Last edited by tahanson43206 (2019-04-01 09:04:25)

SpaceNut · 2019-04-01 16:55:16

I like the image as its some what simular to the skycrane platform which means that if we get one to soft land on mars then we have lots of the existing hardware to make use of in making the CO2 hopper.
https://en.wikipedia.org/wiki/Mars_Science_Laboratory
https://en.wikipedia.org/wiki/Mars_2020

http://jleslie48.com/msl_sc/MarsScience … ne1-24.pdf

Of course no legs on it but thats not all that much mass.

The lander platform for the insight unit would also be very simular to what we would design from.

louis · 2019-04-01 17:24:22

Yes the skycrane is a good starting point I think. Would probably need more side vents as well for lateral travel.

Basically the essentials I would say are:

1. Water extraction system. I favour water being extracted from the atmosphere over a period of around 10 sols. However, this would only allow flying in the summer period, so that is an issue I accept. Question that people might be able to answer: is it absolutely necessary to use water? Can we just use compressed gas - I think the answer is probably yes, in which case let's drop the water idea entirely.

2. Air compression system.

3. PV power array to power scientific instrumentation, coms, gas compression and water extraction.

4. On board computer.

5. Cameras - probably as many as 8.

6. Coms system

7. Heating system.

8. Gas and water storage system.

9. Battery.

10. On board soil analysis system - not v. sophisticated. Maybe gas jets, laser light etc

The hopper needs to be v. lightweight I think assuming I am right that the force provided by compressed air is going to be much lower than on a rocket. Mars's lower G will help here.

SpaceNut wrote:

I like the image as its some what simular to the skycrane platform which means that if we get one to soft land on mars then we have lots of the existing hardware to make use of in making the CO2 hopper.
https://en.wikipedia.org/wiki/Mars_Science_Laboratory
https://en.wikipedia.org/wiki/Mars_2020
https://upload.wikimedia.org/wikipedia/ … 130710.jpg
http://jleslie48.com/msl_sc/MarsScience … ne1-24.pdf
Of course no legs on it but thats not all that much mass.
The lander platform for the insight unit would also be very simular to what we would design from.

SpaceNut · 2019-04-01 18:31:26

https://space.stackexchange.com/questio … nt-on-mars

https://ntrs.nasa.gov/archive/nasa/casi … 179358.pdf
Demonstration of Oxygen and Carbon Monoxide Propellants for Mars Missions

https://ntrs.nasa.gov/archive/nasa/casi … 045922.pdf
Experimental Evaluation of the Ignition Process of Carbon Monoxide and Oxygen in a Rocket Engine

tahanson43206 · 2019-04-01 18:49:01

For SpaceNut #16 ...

From the stackexchange link you provided:

Yes, it could be. The ISP for CO/ O2 is about 200. Compare that to Methane, with a specific impulse of 299, and you can see it's really not that great.
Of some related interest is a hot Carbon Dioxide rocket, with a theoretical ISP of about 260. This would work for short surface to surface hops, but not beyond orbit.

For anyone ... What does the writer mean by a "hot Carbon Dioxide" rocket? Is that ambient temperature, compared to cold, or something else?

ISP of 260 looks pretty good if what the writer is describing is Louis' compressed CO2 rocket.

(th)

SpaceNut · 2019-04-01 19:05:33

web.stanford.edu/~cantwell/Recent_publications/Boiron_AIAA_2013-3899.pdf
Hybrid Rocket Propulsion and In-Situ Propellant Production for Future Mars Missions

The nasa document talks about using the lox and lh2 to start so its quite hot for when the hydrogen is switched off when the Lco is on.

Mars Sample Return (payload of 36 kg) and the medium-scale case (payload of 500 kg) capable of mars escape velocity to return home.

So staying power of flight is throttle control and tank storage levels....

tahanson43206 · 2019-04-02 07:39:43

Design Considerations for CO2 Pizza Delivery Drone for Mars:

SearchTerm:DesignCO2PizzaDrone

Pending Louis picking up the lead on this idea of his, I'll try to move the ball a yard or two ...

Capability:
1) Deliver 10 kilograms 1 kilometer and return to base
2) Operate in normal Mars weather
3) Operate autonomously with monitoring
4) Permit total remote operation as an option

Propulsion method: Compressed Mars Atmosphere: (Carbon Dioxide plus trace gases)

Ideally, the gas would be taken directly from the atmosphere with filtering limited to solid particles

Pressure vessels: Minimum of one, maximum as found most efficient/practical/reliable

Thrust capability: Dependent upon pressure, mass of gas mixture, nozzle design, nozzle throat setting

Control systems: Navigation, Communications, sensing of operating parameters, control of nozzles, control of external lighting, other?

Vehicle structure: Simple, strong, light weight, with outer shell as option for weather protection

Safety features: Descend rapidly and smoothly to ground under vehicle control if necessary

Edit: Optional safety feature: Solid fuel thrusters and control package for emergency landing.

Note: This project would qualify as an Open Source initiative, if carried forward.

(th)

Last edited by tahanson43206 (2019-04-02 21:15:28)

SpaceNut · 2019-04-02 18:48:44

The time it takes to travers the 1 kilometer is imporatant to the design as it can make or break the different proposal methods to be able to achive the goal.
Another would be to have helium tanks to act as bouyancy compensation.
Another could be an RF power transmission scheme for the craft to get power from in order to go the distance on a fixed path.

tahanson43206 · 2019-04-02 21:26:57

OK SpaceNut ...

I've added a Search term to the Design post, and will be ready to add changes as they come in.

You can find it by entering the search string shown below, without spaces:

S e a r c h T e r m : and : D e s i g n C O 2 P i z z a D r o n e

Author: tahanson43206

***
I like your suggestion of specifying a performance time for delivery of a pizza over a 1 kilometer distance.

What time would you consider appropriate? I asked Mr. Google for pizza delivery times, and got a range of preferred times, generally under 30 minutes.

Please note that it might be worth separating flight time from load/unload time.

***
Your suggestion of helium tanks is intriguing but I need a bit of help understanding that one. The vehicle I am imagining would employ compressed CO2 for propulsion, and battery power for control functions, including mechanical actions such as valve operation and pizza clamp/unclamp jaws.

***
The suggestion of a supply of power to the drone is interesting as well, although I was imagining that battery power on board the vehicle would be sufficient for a round trip time of one hour. Can you expand a bit on your idea of RF power supply for the vehicle, and how you would use it.

(th)

SpaceNut wrote:

The time it takes to travers the 1 kilometer is imporatant to the design as it can make or break the different proposal methods to be able to achive the goal.
Another would be to have helium tanks to act as bouyancy compensation.
Another could be an RF power transmission scheme for the craft to get power from in order to go the distance on a fixed path.

tahanson43206 · 2019-04-03 14:53:53

Tried Google search for "cold gas thruster"

This was a productive search. One paper (which I have not yet reviewed) appears to be about a hopper using cold gas ...

http://ssl.mit.edu/publications/theses/ … lSarah.pdf

The above did not come up after repeated tries. It may be saved in tape backup and not online.

Here is a paper that did come up. It is intended for satellite positioning, but (I'm hoping) the design principles should be transferable to a hopper for Mars:

http://cdn.intechopen.com/pdfs/37528/In … llites.pdf

***
I will not object in the slightest if someone with actual design experience in this field were to take a look at the Mars Pizza hopper design challenge.

(th)

Last edited by tahanson43206 (2019-04-03 15:25:49)

kbd512 · 2019-04-03 16:38:35

If all you're trying to do is move 10kg a single kilometer, then the easiest way to do that will be a small rover with a CO2 rotary engine. That negates the need for any fantastic power-to-weight requirements. We already have air powered motorcycles that can take riders 10's of kilometers over rough terrain on a single charge of a SCBA tank. By way of comparison, this little vehicle would be rather small and light. There's obviously terrain to navigate around on the ground, but that's still a heck of a lot easier than managing vertical takeoffs and landings and fantastically more efficient in terms of compressed CO2 expended per kilometer travelled in most cases. If that's not enough of a challenge, then a lighter than CO2 vehicle with a CO2 powered motor could deliver the payload without navigating around terrain.

The dynamic pressure of the wind is so low that significant power would not be required for a balloon to cover that kind of distance. The atmosphere of Mars is so thin that any type of winged aircraft would have to be more harrier than normal airplane. Still doable? Sure, but at what cost? The entire idea is to deliver a small payload (emergency consumables / medical supplies / small replacement parts, perhaps) to someone who needs it.

Maybe you should try all three (ground rover, balloon, harrier) just to determine what the energy requirements for each happen to be and general utility / use cases. I'm guessing that the balloon would be lowest, followed by a ground rover, and the harrier would likely consume the most energy. There would be other trade-offs, though. The balloon might only work at low to moderate speed and above ground, obviously. The rover could enter caves or habitat modules, unlike the other two, but would have difficulty in rough terrain. The harrier would probably be the fastest, out of necessity. It might rocket up into the atmosphere, follow a ballistic trajectory to the target, drop the payload by parachute or soft land it with a last second hover maneuver to reduce vertical descent speeds, and then rocket back to base and touch down there.

Anyway, just some different ideas to play with. Like I said, there are significant trade-offs associated with all 3 methods.

tahanson43206 · 2019-04-03 17:51:11

Just to remind everyone of the origin of this topic, I am quoting the original idea offered by Louis:

louis wrote:

I would have thought compressed gas rocketry would make much more sense on Mars for survey work. Think in terms of something like the lunar lander on a smaller scale. It has a PV array fan that generates the energy to compress the Mars atmosphere. Gas is released and it flies up and with rocket nozzles can accomplish lateral flight for a considerable distance. Takes photos and other survey info as it flies over . Then lands again. Repeats procedure. If it could cover a few kms each time this would be v. useful.

This idea was inspired (as I understand it) by the discussion in another topic, of NASA's testing of a small battery powered helicopter, which is to be included with the 2020 rover.

As kbd512 points out, there are alternatives which have strengths and weaknesses depending upon the mission to be performed.

However, THIS topic is limited (or at least conceptually, might be limited) to discussion of a CO2 pressure powered hopper.

Thus, contributions to design of such a hopper would be welcome.

In a recent post in this topic, I reported finding Google results that are encouraging, in the specific area of cold gas thrusters. Among the papers I found was one that appeared to be a CO2 powered hopper by an MIT student, but my initial attempts to retrieve that paper did not succeed.

(th)

SpaceNut · 2019-04-03 18:32:50

Quite a bit of topic drift but thats ok we can handle it...

I would agree with the suggestion kbd512 to use it for cache delivery to those needing help for sure which means it needs to be an anytime delivery concept as well.

Changing the motor cycle air version to an atv 4 wheeled device is another option for the get on it and go but what I think we need is to be able to do it autotonomus without the human risk factor. This also leaves the possible return of any injured humans instead in the empty location where the cargo once was.

Both options for cache delivery could be covered in the compressed air and recumbent human powered topics as well.

We do have a balloon and airplane topics as well to add to the quest.

Reply to tahanson43206 post #22
On the rocket thruster, cold type these are good for 0g orbital use as they do not have much push to them and need power to heat the working fluid to be expelled out of the nozzle.

Lets post to the other topics for further concept replies and I will duplicate the last few where they should go.

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#1 2019-03-31 07:08:41

Mars Co2 or other compressed Gas Hopper rocket

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