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Wow so old but yet when I was searching for other mars mission of the future this page ended up with just this topic.
Aerobot is a robotic aerial vehicle
Flying
Balloons, blimps and airships are commonplace on Earth, but only two such vehicles have ever flown on another planet. In 1985, the Soviet Union's VEGA project successfully flew two small, wind-blown balloons in the upper atmosphere of Venus for two days.
So whats wrong with doing this on Mars?
Mars has only a tenuous carbon dioxide atmosphere, which means that very large, lightweight balloons are required to float even small payloads of a few kilograms. JPL is focused on developing simple, wind-blown balloons that can fly for weeks or months.
Prototype Mars solar Montgofiere balloon during altitude-control testing.
Also the page meantions there use for Venus and not to get the topic to far off a Venus in Situ exploration mission while we still are waiting to do the same for Mars.
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Balloons, blimps and airships are commonplace on Earth, but only two such vehicles have ever flown on another planet. In 1985, the Soviet Union's VEGA project successfully flew two small, wind-blown balloons in the upper atmosphere of Venus for two days.
Wow, I have never heard about this. Do you have any more info on this, SpaceNut? Would it be worth performing a similar experiment on Mars? What sort of information can be obtained?
- Mike, Member of the [b][url=http://cleanslate.editboard.com]Clean Slate Society[/url][/b]
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Sorry as I have not the time to google this Michael...It does sound interesting thou....
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Balloon
The balloon aerobot was a constant-pressure balloon 3.4 m in diameter with instruments, weighing 25 kg in total. It was deployed at 54 km from the surface in the most active layer of the Venusian cloud system. The 5 kg instrument pack had enough battery power for sixty hours of operation and measured temperature, pressure, wind speed and aerosol density. Both Vega-1 and Vega-2 balloons operated for more than 46 hrs from injection to the final transmission[1].The balloons were spherical superpressure types with a diameter of 3.54 meters (11.6 ft) and filled with helium. A gondola assembly weighing 6.9 kilograms (15.2 pounds) and 1.3 meters (4.26 ft) long was connected to the balloon envelope by a tether 13 meters (42.6 ft) long. Total mass of the entire assembly was 21 kilograms (46 pounds).
The top section of the gondola assembly was capped by a conical antenna 37 centimeters (14.6 inches) tall and 13 centimeters (5 1⁄8 inches) wide at the base. Beneath the antenna was a module containing the radio transmitter and system control electronics. The lower section of the gondola assembly carried the instrument payload and batteries.
The instruments consisted of:
An arm carrying thin-film resistance thermometers and a velocity anemometer. The anemometer consisted of a free-spinning plastic propeller whose spin was measured by LED-photodetector optointerrupters.
A module containing a PIN diode photodetector to measure light levels and a vibrating quartz beam pressure sensor.
A package at the bottom carrying the batteries and a nephelometer to measure cloud density through light reflection.
The small low-power transmitter only allowed a data transmission rate of 2,048 bits per second, though the system performed data compression to squeeze more information through the narrow bandwidth. Nonetheless, the sampling rate for most of the instruments was only once every 75 seconds. The balloons were tracked by two networks of 20 radio telescopes in total back on Earth: the Soviet network, coordinated by the USSR Academy of Sciences and the international network, coordinated by CNES.The balloons were dropped onto the planet's darkside and deployed at an altitude of about 50 kilometers (30 miles). They then floated upward a few kilometers to their equilibrium altitude. At this altitude, pressure and temperature conditions of Venus are similar to those of Earth, though the planet's winds moved at hurricane velocity and the carbon dioxide atmosphere is laced with sulfuric acid, along with smaller concentrations of hydrochloric and hydrofluoric acid.
The balloons moved swiftly across the night side of the planet into the light side, where their batteries finally ran down and contact was lost. Tracking indicated that the motion of the balloons included a surprising vertical component, revealing vertical motions of air masses that had not been detected by earlier probe missions.
Come on to the Future
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hi,
many years are gone since this topic was posted.
What happens to the then ongoing pojects:
- Mars Micro Balloon Probe (R.Zubrin et al. 1999)
- Shielded Marsballoon Launcher (Aurora 2009)
- Delft2Mars (Delft University 2010)
Ballooning is essential to learn about the spurious gases in the atmosphere of Mars, and to reach targets not accessible by rovers over sandy fields.
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I hate my dialup some times as post went out the window......
Did a bit of Googling to see about these as to the status of them...
The Shielded Marsballoon launcher contract was awarded
http://www.marstoday.com/news/viewpr.html?pid=27577
http://www.universetoday.com/25964/nasa … -balloon/#
Shielded Mars Balloon Launcher (SMBL) deployment sequence
Interesting EDL.....
The Delft2Mars is this paper
http://www.planetaryprobe.eu/IPPW7/proc … 1/p408.pdf
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I hate my dialup some times as post went out the window......
Did a bit of Googling to see about these as to the status of them...
The Shielded Marsballoon launcher contract was awarded
http://www.marstoday.com/news/viewpr.html?pid=27577
http://www.universetoday.com/25964/nasa … -balloon/#http://1-ps.googleusercontent.com/h/www … Cqzmb0.jpg
Shielded Mars Balloon Launcher (SMBL) deployment sequence
Interesting EDL.....
The Delft2Mars is this paper
http://www.planetaryprobe.eu/IPPW7/proc … 1/p408.pdf
This article shows what amateurs can achieve on Earth with balloon photos
http://www.metro.co.uk/news/818988-amat … -a-balloon
I wonder if you have a balloon tethered to a robot vehicle, so giving you more control.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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as I read it,
the thether is more to keep the load low, just to supply the camera up with power and communication, thus reducing the size of the balloon to lift that weight, but plus load of the thether. Still that size will be in the range of 10m diameter, which makes it difficult to launch it without to shelter the skin against edies. That "high camera" conzept will give valuable sights over walls or cliffs, where the rover arm can not reach further out than some meters, and the rover driver dare to move closer or higher up to the edge.
The balloon will be an "use when needed" instrument, like the drill, that is carried all the time, but in action only when the soil is promissing.
What is the status of the awarded SMBL (by AURORA corp.)? Is there somebody in this forum to know it?
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Actually, it could be done, with a better buoyancy-defining density ratio there than here. At equal pressures and temperatures otherwise, gas density ratio boils down to molecular weight ratio. That's 2 (for hydrogen) vs 28.97 (for air here) vs 44 (for CO2 there). Mars density ratios are about 50% better.
From a practical standpoint, I would worry about the envelope's survivability: plastics have a very short life on exposure to UV, which is very harsh on Mars. You won't be able to build this dirigible (or balloon, or blimp) out of aluminum. Too heavy. Just like here.
Even here, hydrogen explosions are less of a risk than most folks suspect. The Hindenburg would have burned and crashed, even if it had been filled with helium. The forensic data (confirmed by old insurance records) suggest that the real culprit was static-spark ignition of the doped fabric skin. That dope was nitrate-base (a monopropellant explosive/pyrotechnic), and was pigmented with a mixture of aluminum powder and iron oxide (which is today known as thermite!!!!). The hydrogen just added a little to the yield of the fire. But the flame propagation speed along the Hindenburg's skin was around 10 times what fully-premixed hydrogen-air is capable of. And it wasn't even pre-mixed.
The ONLY real problem with a smallish hydrogen-air flame here on Earth is that you can't see it in full daylight. But, on Mars, you won't even have one at all in a CO2 atmosphere.
From a design standpoint, the real design problem with a Martian dirigible/blimp/balloon is that the material-of-construction weight only scales down by 0.38 (for the strength of gravity), while actual gas densities scale down by 7mbar out of 1013, roughly. A dirigible/blimp/balloon on Mars will have to be very much larger in proportion to its useful payload there, than here.
But, yes, it could be done. And safely.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Some animations of a model we had a few years back at 41 seconds- http://www.youtube.com/watch?v=IAcQMMyP8MI&feature=plcp
welcome to [url=http://www.marsdrive.net]www.marsdrive.net[/url]
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repost:
Here's what JPL's 1997 Mars Geoscience Aerobot project came up with:
Mars 2001 Aerobot / Balloon System Overview
Mars 2001 Aerobot / Balloon System Overview - Additional Info
Mars Balloon Trajectory Model for Mars Geoscience Aerobot development
I presume that lighter and stronger materials would enable a heavier payload and 20 years of electronics advancement would negate the need for a heavier payload for aerial observation, but it's not necessary to invoke the use of any new materials just to create something that would work from a physics standpoint.
Roughly 500,000 cubic meters of balloon would be required to lift a 1,000kg payload. That's 2.5 times the volume of the Hindenburg. I don't envision such airships will be traditional spheres or blimps, but very large donuts attached at multiple points to cargo pods slung below. The French experimented with balloons that circled the Earth at altitudes of 35km decades ago. Their longest duration flight was about 69 days.
A 1t lift capacity toroidal balloon would have a major radius of 50m and a minor radius of just over 22.5m. A series of CNT ropes (these can now be purchased as commercial products, even if they're still obscenely expensive) would suspend the cargo beneath the balloon. An evacuated double-wall torus could be significantly smaller or carry significantly more cargo.
The surface area is many thousands of square meters, which provides adequate area for a sizable thin film solar array for electrical power and a propulsive surface for the ionic wind thrusters to push off of. It won't be a speed demon, but doesn't require much infrastructure to ship supplies over great distances to field geology teams hunting for resources.
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So what are typical windspeeds in the lower parts of the Martian atmosphere? How long do high wind periods last?
The Martian atmosphere is much more variable than ours. South pole summer liberates a lot of CO2, raising the atmospheric pressure across the planet and the huge range of relief between Hellas' bottom and Tharsis' tops means that one blimp design can't visit a lot of places if it must carry a useful payload.
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re-posting
The wind speeds in the lower atmosphere are 2m/s to 5m/s (edit: can't recall if the NASA doc said 5m/s or 7m/s, but the difference is still negligible) or thereabouts. The winds in the upper atmosphere can top 50m/s.
A very large toroidal aerostat could also lift thin film solar arrays draped over the top of the aerostat as the payload, in order to rise above most of the dust in the lower atmosphere. A lightweight conductor would carry the power back to a battery on the surface. This would reduce the variability of the power received as a function of the Tau of the atmosphere and permit easier mission planning around photovoltaic power.
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https://asd.gsfc.nasa.gov/balloon/2nd_t … rich_1.pdf
Some of this work on a balloon for mars as been in the works for nearly 2 decades from a brief search
https://ntrs.nasa.gov/search.jsp?R=20010023115
https://en.wikipedia.org/wiki/Aerobot
http://www.gaerospace.com/space-explora … -balloons/
some of the work overlaps Venus as well with regards to the application
http://www.gaerospace.com/space-explora … e-balloon/
https://www2.jpl.nasa.gov/adv_tech/ball … usmatl.pdf
I think for mars the shape of a wing long and slender would aid in getting the little bit of lift from air flow.
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bump
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Some thoughts.
1. A blimp is an interesting idea. A spherical hydrogen filled balloon 100m in diameter would lift about 6.5 tonnes on Mars. Subtracted from that would be the mass of the envelope, fuel and propulsion.
https://en.wikipedia.org/wiki/Solar_balloon
Mylar reflectors to heat a section to make it rise or to create power for it to change or manuever direction.
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Calliban,
The idea I had in mind for blimps was an inflatable torus covered in a thin film solar array to supply electrical power to ground vehicles and equipment. The blimp would be used to ferry bulk cargo (water, minerals, ores, tools, portable inflatable habitat modules) from a work site to a processing plant. The tracked vehicle would tow the blimp to and from the work site, receiving power from the blimp and negating the need for the tracked vehicle to bear the weight of or supply a lot of power to move the cargo. This offsets the need to lug batteries of additional fuel tanks to supply power to the electric motors
Still there is going to be a need for power conditioning for load currents, voltage sag from conductor dropout...
The flat level array will also not generate the power levels for the known cell efficiency in fact on earth they only deliver 1/9th of what they would normally output.
So if there is a way to have them track the sun from the top of a means to do so could be designed then as you note it does reduce the mass that the equipment would need to lug around. That would increase time of operations for the same power source.
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I sort of like the idea of solar on the top of the blimp but laying them flat not aligned for the sun has a much lower output from them.
I have seen outputs of 1/9th of what is expected due to being level.
https://en.wikiversity.org/wiki/Practical_Solar_Power
https://us.sunpower.com/how-many-solar- … ut-factors
https://www.energymatters.com.au/reside … olar-faqs/
https://www.gonewiththewynns.com/tilt-rv-solar-panels
What if we use a two blimp stack up where the lower acts as a reflector to the bottom of the blimp above the lower one..the shape of the reflector can then be adjustable such that they point the energy to the panels, parabolic compound to direct the energy to the solar panels above.
Aluminized mylar. Or aluminized polymer film.
http://newmars.com/forums/viewtopic.php … 57#p130457
Solar powered dirigibles are an interesting idea, but depend upon the efficacy of extremely light-weight thin-film solar cells.
Going back to the example of a spherical hydrogen filled balloon 100m in diameter. The total lift provided would be 6.5tonnes. That is 0.207kg/m2 of envelope area. The solar cells, envelope, propulsion system and cargo, must weigh no more than 207 grams per square metre of envelope. Thin solar cells must operate at low voltage, which would lead to significant losses even across the circumference of the balloon. Maybe we can do clever things, like printing the cells on the inside of the envelope and using the envelope itself as a cover and UV shield for the cells?
A similar idea would be to cover the balloon in solar cells and tether it to a ground vehicle via an electrical cable. The balloon then carries the power supply for the vehicle; and the vehicle carries the payload. The top speed and payload capacity of the ground vehicle would be a function of sunlight intensity. Excess power would go into life support functions. At full sun on Mars, a 100m diameter balloon covered in 10% efficient solar cells would provide about 400kW of power. This would vary sinusoidally throughout the day. At night, power would be zero and driving would stop.
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Nasa has been looking into the blimp with solar cells on the upper surface for a venus mission so there is quite a bit of design which could be fed forward for this consept.
http://newmars.com/forums/viewtopic.php?id=7426
http://newmars.com/forums/viewtopic.php?id=5963&p=16
http://newmars.com/forums/viewtopic.php … 15#p135015
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Space robotics startup Lux and satellite developer ResearchSat are both participating in Australia's first space incubator program at the
University of South Australia's Innovation and Collaboration Centre (ICC) startups launch successful space balloon
ResearchSat is developing small satellite payloads which can take microbiological experiments to space.
"We are working with miners and engineers on what valuable data we can provide them with. We are already planning pilots with three local mines next year to launch space balloons on their sites,"For the test launch, the team sent up a helium balloon to an altitude of 30km - three times higher than a commercial aircraft - for two hours, tracked it using GPS, then burst it - safely capturing its payload attached to a parachute.
"Our product is a subsystem of a CubeSat so we needed an external 'bus' to test the functionality of the prototype and collect data. Lux's space balloons were the perfect vehicle to make this happen. We now have enough data on our current technology ready for our major launch via rockets next year,"
Venture Catalyst Space program
https://icc.unisa.edu.au/programs/ventu … yst-space/
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For SpaceNut re #92
Thank you for the infograph (a term I'm picking up from kbd512) comparing various fuels (liquid and various pressure gas forms).
I followed the Storage Tank link and followed the manufacturer's summary of their progress in meeting DOE goals for hydrogen storage for shipment.
This topic is not the right place for what I am looking for, which is a way of evaluating the use of lifting property of Hydrogen at 1 bar to ship the gas via blimp. The question that occurs to me is what compression is feasible (a) and (b) cost effective for a blimp shipment method.
The pdf from the manufacturer of hydrogen shipping containers estimated 90% throughput for a shipment using their equipment.
Is that a figure that would work for a blimp transport system?
The Earth's winds could be enlisted to move blimp Hydrogen transports from the point of manufacture to a destination, if enough time is available before losses exceed acceptable levels.
(th)
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I guess one could solve this a few different directions.
1. just use the blimp itself for the transporting container.
2. use the tank methods of transport.
3. drag a tanker vehicle by blimp
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For SpaceNut re #97
The Wikipedia article on lifting_gas seemed doubtful of the possibility of building a practical lifting device on Mars, due to the low density of the atmosphere.
The option to "drag a tanker by blimp" would appear to be unavailable on Mars, but (apparently) a blimp could be filled with gas and carried on the back of a crawler as a less expensive option than using high pressure tanks.
I hope someone will run the numbers on these options. I would certainly be interested to see the results.
(th)
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Does not really answer the lift question but the shape is interesting.
Can a blimp dead drop on Mars or Earth this way?
Evacuated Airship for Mars Missions
vacuum airship may theoretically carry more than twice as much payload as a modeled dirigible of the same size, a 40-meter radius, in the Martian atmosphere.
Martian blimp topic...
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Now I remember hot to make a blimp fly on mars as you fill the balloon partially and then heat the gas to make it expand to finish inflating the blimp.
https://www.quora.com/What-is-the-best- … rs-Airship
The internal vaccumn is inside an area that will not collapses with an outer shell that use helium to make the ship take shape.
At standard sea level pressure every cubic metre contains 1.292 kilograms of air, but a cubic metre of hydrogen or helium contains only 90 grams or 178 grams respectively; producing a lift of 1.202 kilograms or 1.114 kilograms.
Now, as lift depends on the mass of gas you can push out of the way, in theory the best possible balloon would have nothing in it at all and provide the full 1.292 kilograms lift for every cubic metre.
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