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I just mailed the letter to Elon Musk that transmits the notion of the barrel-roll tank settling for their Starship tanker operation. The same mentions that we have a Mars engineering lander proposal he might want to see, and why.
Draft 6 has the revised cover letter for the revised probe design, but the data/detail appendix is not revised from draft 4 yet. No the probe no longer looks like what I had sketched before, with the tractor rocket tower. It looks more like the MER design, although I am thinking if we substitute liquid storable braking rockets for the solids that MER used, we could touch down without the airbags that MER used.
That actually saves some weight because we no longer need the petals, the righting system, or the airbags or their pull-back system. And it reduces a restriction on how to get the rover off the platform, because no deflated airbags can get in the way. We might be able to afford 30-50 kg worth of drill on the lander that way.
About drills: my researches indicate the MASA drill on ESA's ExoMars probe (2022 launch) is an update to the drill the Finnish fellow worked on, in his PhD thesis. The one he worked on drilled 2 meters max, with limited reliability below 1 m. The MASA thing which is going to fly drills 2 to at most 2.5 m down. Neither is enough.
We really need the CanaDrill device that NORCAT built and tested ca. 2002. It was supposed to be capable of drilling 10 m down. But, since it and a JPL probe proposal that was supposed to carry it were never done by NASA, it seems to have disappeared. I looked at NORCAT's website. There is not one word about the CanaDrill there. I have seen a mass for Canadrill reported as 45 kg, but nothing about what that does, or does not, include. I have seen no dimensions for it at all. Only a wild guess on my part says the rotary drill magazine is a meter long.
RobertDyck has seen this thing being tested. I sure would like some feedback from him about dimensions, masses, and test results. Maybe also about whether or who I might contact at NORCAT. Somebody somewhere must still have the drawings for this thing.
GW
PS -- an angled tractor rocket at 45 degrees has 70.7% of straight-on axial thrust and impulse. It's the cosine of the angle off axial.
Last edited by GW Johnson (2021-09-18 12:21:28)
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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got it for the angle formula its been a while...
A spark may be all it takes to have them come and read the forum even if they do not become a member...
So our lander looks more like these
Compared with Phoenix, though, InSight's landing presented four added challenges:
InSight entered the atmosphere at a lower velocity -- 12,300 miles per hour (5.5 kilometers per second) vs. 12,500 miles per hour (5.6 kilometers per second).
InSight had more mass entering the atmosphere -- about 1,340 pounds (608 kilograms) vs. 1,263 pounds (573 kilograms).
InSight landed at an elevation of about 4,900 feet (1.5 kilometers) higher than Phoenix did, so it had less atmosphere to use for deceleration.
InSight landed during northern hemisphere autumn on Mars, when dust storms are known to have grown to global proportions in some prior years.
https://www.nasa.gov/pdf/226508main_pho … nding1.pdf
https://www.nasa.gov/pdf/213817main_mars-phoenix2.pdf
https://solarsystem.nasa.gov/missions/phoenix/in-depth/
1. Robotic Arm (RA)
2. Microscopy, Electrochemistry, and Conductivity Analyzer (MECA)
3. Robotic Arm Camera (RAC)
4. Surface Stereo Imager (SSI)
5. Thermal and Evolved Gas Analyzer (TEGA)
6. Mars Descent Imager (MARDI)
7. Meteorological Station (MET)
This was the landing platform for the MER's
Last edited by SpaceNut (2021-09-22 19:19:51)
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For SpaceNut ....
I'm not sure if GW Johnson is staying on his original course, but if he is, you'll recall that he specifically omitted legs of any kind from the drill lander. Instead, his description called for small fins or ribs that would dig into the regolith to prevent rotation of the lander due to torque of the drill.
However, it is possible he's dispensed with that concept along with the retro jets.
I have not yet had (made) time to read Draft #6, so am fanning the air here.
(th)
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Drawings have been omitted and no talk other than to want the original NORCAT CanaDrill device drilling through hard rock for the lander.
No real description for the lander other than to not use the skycrane or bouncy ball air bags.
The lander image could still have under the platform the 2 large soil barbs or fins versus the legs with the propulsion being nearly the capacity that we would want.
Both previous landers had the origami solar panels but we could still make the fold ups work.
We are still at the mercy of the back shell height for the main drill unless we solve how to segment the lengths needed for depth.
The rovers have shifted to using the planned esa drill sampler with less junk on them still solar powered.
Mission is targeting a short duration to keep costs down possibly just 90 days...
One of the things to remember is that an image can give details hard to put into words..
I did a bit more image searching for the Mars NORCAT CanaDrill and see no reason that the image is not duplicatable.
By the way the number 3 search was our topic for bing
found another topic with postsstarting here with oldfart1938 and Robert Dyck talking about the norcat candrill
Oh to Be Boring on Mars: Canadian Drilling Technology Demonstrated
THE ADAPTATION OF TERRESTRIAL MINING EXPLORATION DRILLING TECHNOLOGY TO SPACE
Did we miss it?
The "Canadadrill" weighs about 100 pounds and would use a rotating core drill bit with fused diamonds. Alain Berinstain, the agency's Mars Project lead.
Alain Berinstain, the Canadian Space Agency scientist in charge of the project, said no other greenhouse is designed to operate autonomously like the Arthur Clarke Mars Greenhouse on Devon Island in Nunavut.
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edit
adding content for landers.
https://mars.nasa.gov/insight/spacecraf … he-lander/
https://en.wikipedia.org/wiki/InSight
InSight cruise stage departed Earth at a speed of 10,000 kilometres per hour (6,200 mph)
Several minutes later, the aeroshell containing the lander makes contact with the upper Martian atmosphere at 12,300 mph (19,800 km/h
Overall specifications
Mass
Total mass during cruise: 694 kg (1,530 lb)[3]
Lander: 358 kg (789 lb)[3]
Aeroshell: 189 kg (417 lb)[3] Aeroshell Diameter (backshell and heat shield) : 2.64 meters (8.67 ft)[3]
Cruise stage: 79 kg (174 lb)[3]
Propellant and pressurant: 67 kg (148 lb)[3]
Relay probes flew separately but they weighed 13.5 kg (30 lb) each (there were 2)[3]The spacecraft's mass that entered the atmosphere of Mars was 1,340 lb (608 kg)
Lander specifications
Lander mass: 358 kg (789 lb)[3] including about 50 kg of science payload.
Mars weight (0.376 of Earth's):[60] 1,320 N (300 lbf)
About 6.0 m (19.7 ft) wide with solar panels deployed.[3]
The science deck is about 1.56 m (5.1 ft) wide and between 0.83 and 1.08 m (2.7 and 3.5 ft) high (depending on leg compression after landing).[3]
The length of the robotic arm is 1.8 m (5.9 ft)[3]
Tilt of lander at landing on Mars: 4°[Solar panels yielded 4.6 kilowatt-hours on Sol 1
This was the one which went splat on the surface...
https://solarsystem.nasa.gov/missions/m … /in-depth/
Spacecraft Mass Total: 1,270 pounds (576 kilograms)
Lander: 639 pounds (290 kilograms)https://solarsystem.nasa.gov/missions/phoenix/in-depth/
Spacecraft Mass
Total: 1,464 pounds (664 kilograms)
Lander: 772 pounds (350 kilograms)https://www.nasa.gov/pdf/226508main_pho … nding1.pdf
Spacecraft
Cruise vehicle dimensions: Diameter 2.64 meters (8.66 feet), height 1.74 meters (5.71 feet);
span of cruise solar arrays 3.6 meters (11.8 feet)
Lander dimensions: Height to top of meteorology mast 2.2 meters (7.2 feet), or slightly less
depending on legs absorbing impact; span of deployed solar arrays 5.52 meters (18.1
feet); deck diameter 1.5 meters (4.9 feet); length of robotic arm 2.35 meters (7.71 feet)
Mass: 664 kilograms (1,464 pounds) total at launch, consisting of 82-kilogram (181-pound)
cruise stage, 110-kilogram (242-pound) back shell, 62-kilogram (137-pound) heat
shield, and 410-kilogram (904-pound) lander That lander mass includes 59 kilograms
(130 pounds) of science-instrument payload and 67 kilograms (148 pounds) of fuel
Power: Solar panels and lithium-ion batteriesA pair of rechargeable 25-amp-hour lithiumion batteries provides power storage. T
Science payload: 59 kilograms (130 pounds) consisting of Robotic Arm; Robotic Arm Camera;
Surface Stereo Imager; Thermal and Evolved-Gas Analyzer; Microscopy, Electrochemistry and Conductivity Analyzer; Mars Descent Imager; Meteorological StationLaunch Vehicle
Type: Delta II 7925 (three-stage)
Height with payload: 39.6 meters (130 feet)
Mass fully fueled: 231,126 kilograms (509,538 poundsThe spacecraft fired its four mid-size thrusters for 3 minutes and 17 seconds. This changed velocity by 18.5
meters per second (41 mph), a small amount in proportion to the spacecraft’s velocity relative to the
sun at the time: about 33,000 meters per second (74,000 miles per hour).Phoenix communicates directly with Earth using the X-band radio spectrum (8 to 12 gigahertz) throughout the cruise phase of the mission. The spacecraft carries two copies of its cruise communications equipment, providing redundancy in case of a problem with one of them. The mission will use ultra high frequency (UHF) links (300 megahertz to 1,000 megahertz), relayed through Mars orbiters during the entry, descent and landing phase and while operating on the surface of Mars. A UHF antenna on the back shell will transmit for about six minutes between the time the cruise stage is jettisoned and the time the back shell is jettisoned.
https://www.researchgate.net/publicatio … ng_on_Mars
https://www.nextbigfuture.com/2018/09/o … -mars.html
https://www.hou.usra.edu/meetings/lpsc2015/pdf/2417.pdf
Drilling on Mars: What We Have Learned from the Mars Science Laboratory Powder
Acquisition Drill System (PADS),
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For SpaceNut re #179
I followed the bottom-most link you provided and found this paper from 2007 ...
OPC DataHub Supports Lunar Mining Mission
Share Article
NORCAT and the Canadian Space Agency are using the OPC DataHub to help develop a hard-rock drill for upcoming missions to the moon and Mars.That was a pretty easy part of the overall work of the project. We were working at a deep level, beyond the scope of the API documentation, and any time we ran into a problem the technical people at Cogent came back right away with the solution. The support was above and beyond what I would expect.
(PRWEB) JULY 12, 2007
NORCAT, a mining technology company in northern Canada, is relying on the OPC DataHub from Cogent Real-Time Systems to prepare for upcoming space missions. Under the supervision of NASA and the Canadian Space Agency, NORCAT is developing a hard-rock drill capable of taking samples from the moon and Mars under extreme conditions, with no human operator.
"We are very pleased with the responsiveness and high quality of Cogent's support," said the project software designer. "Any time we ran into a problem the technical people at Cogent came back right away with the solution. The support was above and beyond what I would expect."
The drill will be used first on a mission in 2011 or 2013 to Shackleton Crater at the south pole of the moon. Scientists believe they may find traces of water there in the form of ice, as close as one meter to the surface. The most likely location is in shadowed areas, shielded from the burning rays of the sun, but also completely cut off from radio contact on earth. Thus NORCAT's drill must operate completely autonomously--drill through different types of rock, extract samples, and put them into a crusher--all without any human control whatsoever. It must be pre-programmed to anticipate any irregularities and potential hazards in the process, and respond accordingly.
Replacing PLCs
Tom Atwell, Senior Systems Integration Specialist at NORCAT, is responsible for developing the autonomous controller for the drill. Most of NORCAT's drills are controlled by PLCs, but autonomous control requires much more sophisticated capabilities than a PLC can provide. To get this level of processing, Tom has been using a Q5 controller from Xiphos Technologies in Montreal, Canada. The Q5 is an FPGA-based embedded control board that includes a Linux/PowerPC platform.. It has the processing power that Tom needs to run highly complex control scenarios.
I wonder of NORCAT is still in existence. It ** sounds ** to me as though a mining company was enlisted to design a drill for the Moon.
The article from which I pasted a portion describes details of how software was adapted to changes of hardware for controlling the drill.
(th)
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Norcat appears to still exist ....
Per Google:
NORCAT
4.6 (131) Occupational safety and health in Sudbury, Ontario
Directions
Website
Address: 1545 Maley Dr, Sudbury, ON P3A 4R7, Canada
Hours: Closed ⋅ Opens 8AM Mon
Phone: +1 705-521-8324News | NORCAT
www.norcat.org › news
Strata Worldwide Opens First Canadian Office at NORCAT Underground Centre ... NORCAT is one of ten Northern Ontario mining supply and service companies ...NORCAT - Skills Training for the Future
www.norcat.orgNORCAT is a leader in skilled labour training/development that builds and delivers programs, services, and resources that enhance productivity and safety.
About NORCAT
www.norcat.org › about-usNORCAT was founded in 1995 by a team of business and academic visionaries who ... There is always room for improvement and we can always do better.
NORCAT - Wikipedia
en.wikipedia.org › wiki › NORCATNORCAT is a not for profit technology and innovation centre headquartered in Greater Sudbury, Ontario, Canada. ... NORCAT provides health and safety training for the mining industry, ...
Strata Worldwide opens first Canadian office at NORCAT ...
www.northernontariobusiness.com › press-release › strata-worldwide-opens...
Aug 30, 2021 · The NORCAT Underground Centre is an operating underground mine developed to provide both practical, hands-on training for new miners in the ...Strata Worldwide opens NORCAT office - Mining Magazine
www.miningmagazine.com › fleet › news › strata-worldwide-opens-norcat-...
Sep 1, 2021 · The company stated that the new partnership will provide an 'unparalleled resource' in supporting its growth into the Canadian market.Deloitte and NORCAT | Deloitte | Energy & Resources
www2.deloitte.com › global › pages › energy-and-resources › articles › del...
OK... who's going to call them? They appear to be alive and well as recently as September 1st of 2021.
(th)
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There appears to have been no missions during the time period referenced
https://en.wikipedia.org/wiki/List_of_m … o_the_Moon
https://moon.nasa.gov/exploration/moon-missions/
That said Nasa must still have copies of the work design for them some where.
Norcat does not appear to be the same business that it was back then and if you follow the names they are doing business under the Sudbury mining...which I posted back in the other grouping of stuff
post 99 for
https://deltion.ca/mining-in_space/
Dale Boucher
CEO
705-824-1500 x21
dboucher@deltion.ca
His name shows up in post 99
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Number 7 is in hand and looks like we have a bit of change to where we started.
The determining of "two critical pieces of engineering information about any proposed manned landing site" is ground proof verification or quantitative measurement confirmation from other wise orbital indirect science.
It is by that which makes it "definitely NOT a science mission" but one of acknowledgement of result from orbital science with test measurements from this mission.
By virtue the proposed lander rover drill pounder mission makes for a not "competing for science missions" but for setting up the future for manned mission. We have set in motion sooner rather than later the planning with confirmed results of values to ensure success at the tested sites.
Now on this content I am confused as "air bags are inflated for a free-fall landing" as I though the base had prongs to make the lander stationary so that it would not turn?
Now on this content I am confused as "enclosure petals open, first using one of the petals to right itself, then the deflated air bags are retracted mechanically" again not if we need a driving impact to seat the lander into the ground hard.
A drop ramp for the rover to drive off the platform should be relatively easy to deploy once down on the ground.
Here is the MER EDL for mars
https://ntrs.nasa.gov/api/citations/200 … 014638.pdf
https://ntrs.nasa.gov/api/citations/200 … 095912.pdf
Mars Exploration Rovers Entry, Descent, and Landing Trajectory Analysis
The only thing in the was the rover so that will not do....
https://www.nasa.gov/pdf/501326main_TA0 … 2010-A.pdf
DRAFT Entry, Descent, and Landing Roadmap
Technology Area 09
November • 2010
Advanced Mars EDL Technologies for Manned and Unmanned Missions
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First deep drilling success for ExoMars
ESA's Rosalind Franklin twin rover on Earth has drilled down and extracted samples 1.7 metres into the ground - much deeper than any other martian rover has ever attempted.
Rosalind Franklin's drill works on rotation. A series of tools and extension rods are fitted to form a 'drill string' and can reach the full 2m length when all are connected.
The drill can penetrate the ground at 60 rotations per minute, depending on the consistency of the soil. Digging into sandy or clay solid materials could take between 0.3 and 30 mm per minute.
The drill has also a two-degree of freedom positioner that allows it to discharge the sample at the right angle into the rover laboratory.
https://www.esa.int/Science_Exploration … on/ExoMars
The drill reminds me of the granite and concrete types that I have seen
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This is primarily for GW Johnson, although I invite (and encourage) comments by all
I bring up this topic as it was discussed--albeit in passing--at the Rocky Mountain Chapter of the Mars Society yesterday evening. The question seems to be having the ability to differentiate resident Martian organisms from Earth-borne contamination. My answer was blunt and unequivocally "Not a problem." It amounts to finding any organism which is based on DNA/RNA/proteins, versus anything else. Any other life form would be unquestionably unique w/r to it's biochemistry, but similar but Martian life forms would undoubtedly have some entirely different genomic character, immediately setting them apart from all know Earth genomes. My argument is the Planetary Protection advocates are refusing exploration and development of the planet until they are satisfied there are no native life forms extant, is utter hogwash. Any competent Biochemist would have no problem making this differentiation, given a suite of state of the art gene analyzers. The Planetary Protectionists seem to be within the Planetary Science group at NASA/JPL. Once we go to Mars, the "rice bowl of funding" they've enjoyed building probes and rovers goes almost entirely away.
Comments?
This post showed up when I was investigating the problem of how to (carefully) repair old posts from the days before FluxBB.
I recognized that this topic (Planetary Protection) is a major bug-a-boo for Dr. Johnson, if he intends to enlist NASA or any organization associated with NASA to help with the engineering probe initiative.
I am recommending that NO precautions of any kind be taken to prevent Earth life from presence on any of the probes to be constructed and deployed on Mars. The Science community has had decades to look for life on Mars, and at this very moment, Curiosity is saving samples from various locations for later retrieval. In my opinion, those samples are going to be sufficient to satisfy the science community.
Because of the risk of Planetary Protection folks taking over the development of the engineering probes, I recommend doing everything possible to find another spacecraft integration team.
(th)
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For GW Johnson ... I just ** make ** time to scan Draft #7 .... I'm planning to go back for detailed review later today.
Editorial item: Please change "a" to "an" in the sentence that begins "I write" (just before "engineering").
Page 2 .... Paragraph that begins "There is"
I am still (increasingly) worried about Planetary Protection interference ... Dr. Zubrin would be a strong ally if you can enlist him to help.
Page 5
I am ** glad ** to see the adjustment to landing shown in bold !!! Yay !!!
OK ... that's enough for now!
(th)
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I'm not sure how to deal with the planetary protection idiots. Yes, the craft needs to be decontaminated. Such shouldn't hurt the drill, or the ball-drop tester. The rest of it being about the same as the original MER probes, then why would not those same decontamination efforts be just as good now as they were then?
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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For RobertDyck ... thanks for providing a link to NORCAT's contact information....
NORCAT Sudbury
1545 Maley Drive
Greater Sudbury, ON, Canada
P3A 4R7705-521-8324
support@norcattraining.com
For GW Johnson ... do you want me to call them or send an email, or would you prefer to handle this yourself?
(th)
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GW,
It's driven by irrational fear and paranoia, so no planetary protection measures will ever be sufficient. The only thing that's materially changed between now and then is the general level of irrational fear over natural phenomenon that are largely outside of human control, in conjunction with the increasing obsession over controlling things that can't be controlled. Either way, we'd better get this show on the road before most of the populace in the westernized world is completely off their rockers.
In a worst case scenario, we need to design a low-power / low-speed coring drill and regolith compaction tester that were "invented" at NASA / JPL, so we can "re-imagine" punch holes in rock and dropping ball bearings in sand. If that's even mildly taxing the capabilities of our space exploration agency, then there's little hope of colonizing Mars.
In light of that reality, what are our best arguments both for and against starting from scratch by designing simple yet durable tools that don't make a mountain out of a mole hill?
NASA won't have a spacecraft of any kind that's ready for launch in less than two years, so there's plenty of time to design and test the mission tools. We'll inevitably hit a dead-end in our search for off-the-shelf designs, or discover that nobody's properly tested their science project in a realistic operating environment.
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For kbd512 re #190
Pessimism and doubt surely have a place in human interactions. They have the beneficial effect of scouring more optimistic points of view to expose weaknesses.
Even GW Johnson did not initially think it is possible to achieve the 2022 launch date with one set of probes, let alone 12 of them.
However, I am here to sustain the delusion of capability of Americans and their allies to achieve otherwise impossible goals.
This topic was set up to put at least one lander on a launcher in September of 2022 and the game will remain in play through September of 2020.
I do think the planetary protection idea has run it's course, and no time needs to be added to the preparation time of the landers and their support systems for the purpose. If the planetary protection folks want to spray disinfectant on non-critical parts they can do that in parallel with the main activity.
Regarding restarting from scratch ... that might well be a practical idea, given sufficient funding. However, it is ** way ** too early to give up on finding already designed, built and tested systems to perform both functions.
One thing I can say with confidence ... it will take a ** lot ** of good will and positive "cando" attitude to pull this off.
SearchTerm:Peptalk for Lander Team facing daunting obstacles and enormous head winds
Suggestion: Not one penny of whatever funds are raised to support this venture needs to be allocated for Planetary Protection procedures or supplies.
If someone wants to fund such activity then they are free to do so, independently of the main flow to put landers on the surface, and without impeding or slowing work on the main track in any way.
(th)
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For GW Johnson re Draft 8 ...
Pages 1 and 2 look good ...
Pages 3 - 8 are in line for detailed review tomorrow.
My overall impression is good.
For kbd512 ... would you be willing to double check the figures?
That's not my forte, and they deserve careful scrutiny, because they'll certainly get it if this gambit succeeds.
(th)
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tahanson43206,
I'm not being pessimistic, nor do I think this is any sort of monumental challenge. It simply has to be done prior to landing humans, in order to retire risk. While not nearly as glamorous or sexy as a crewed landing or a big fancy scientific robot, it provides vital engineering data. I looked over Draft 8 of the proposal. I'm reasonably certain that we can design a practical drill within those mass constraints, and will likely come in on the light side of those figures, especially with composite drill pipe and engineering plastics for mounting the drive.
One thing that stood out in my read-through, though, was how or why we're so certain that we could design a pure retro-propulsive landing system within the same vehicle mass constraints. I presume GW already ran numbers, but is this retro-propulsive landing system a clean sheet design? If so, then why are we modifying spacecraft reentry and landing system designs that are already proven to work on Mars? Is there a considerable mass advantage associated with doing that? If not, then why are we doing it?
Edit:
This is the kind of stuff that turns 1 to 2 year projects into 5 year projects.
Stick with all the exact same technologies that have worked so well for the landers and rovers. If this is what GW meant (use the retro-propulsion package from Mars InSight, but fitted to a rover's landing stage, then fine, but no new engineering that's not absolutely required to complete the mission.
Last edited by kbd512 (2021-09-21 23:08:34)
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For kbd512 ... thanks for taking the time to look at Draft #8
Please try to find time to scrub the numbers thoroughly.
This is a ** sales ** presentation. Dr. Johnson is bidding for a job here, and he is trying to present an attractive future to the potential customer, ** and ** he is trying to show he (and his team) is competent to be entrusted with ** real ** money to carry out the project in a tight time frame.
The customer who funds this will have a fixed mass to work with (either Falcon 9 or Falcon Heavy) and whatever budget they can justify to their Board.
What I think GW Johnson is trying to show is a willingness to try for minimal mass while achieving the stated mission objectives.
The use of bouncy bags detracts from the impression of seriousness, and it ** certainly ** does not allow for a high precision landing, which is ** required ** for this mission. The precision landing system already demonstrated in landing of Curiosity would seem required. The retro rocket concept has been demonstrated multiple times in successful landers. The only difference I see in this case is that the retro rockets stay with the lander since there is no need to discard them.
What you can do to enhance prospects of success is to study the numbers included in the Draft, and report any errors there might be.
This document is NOT intended to show the final result. It ** is ** intended to show competence, and that's where the team comes in.
(th)
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tahanson43206,
When you say "scrub thoroughly", I presume you mean review the mass figures from past successful missions, look up the masses of the various vehicle or scientific instrument subsystems (if available- not all of them are), and determine whether or not our proposal comes in at or under those mass figures (because if it doesn't, then the vehicle and mission require a redesign)?
That's going to take some time to do a thorough analysis, because I need to dig up the available documents from NTRS.
I'm not opposed to retro-propulsion, bouncy bags, or any other technology used that allows the mission to proceed with minimal cost and complexity. I was simply considering how NASA managed to achieve the required entry mass target using then-existing technology. If there's a less costly or complex way to land using retro-propulsion, then I'm all in favor of doing that.
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For kbd512 re #195
Thanks very much for your continued interest in and support of the immediate activity ...
I've just completed an "editorial" review of pages 3-8. My skills are more in the area of language than numbers, and I have some suggestions to offer GW Johnson. Regarding numbers ...
There appear to be only a very small set of numbers that need attention ... remember, the idea here is to insure that GW Johnson comes across as competent and able to lead a team.
I don't think the numbers quoted on page 5 need more than a quick check against the source.
SpaceNut, please take that on.
On page 6, we have some calculations.
kbd512, those calculations are what I am asking you to verify.
They are almost certainly right! I am requesting you to verify that they ** are ** right.
You can be absolutely sure that if the document reaches the intended audience, those numbers will be examined closely.
We do ** not ** want errors to show up at that point!
The same is true of a small set of numbers on page 7.
I am confident they are right. I'd like for you to tell us that they ** are ** right.
The same is true of a small set of numbers on page 8.
Once again, I am confident they are right, but I'm not willing to bet the outcome of the game on confidence.
With your help, we can be ** certain ** those numbers are right.
***
For GW Johnson....
The deep editorial review yesterday covered pages 1-3.
Today, I picked up on page 4.
Page 4 passes muster.
Page 5 has a problem ... please take a look at the line at the bottom that begins: "as this test is"
I think the word "more" is not needed, but I don't claim to understand at your level, so invite your review of that sequence.
Page 5 also has a (possible) problem that I will call to your attention...
The paragraph that begins: "A radar altimeter" seems to describe the use of air bags.
Subsequently, there is a section that appears to recommend against use of air bags.
My sense of this is that the historical use of air bags has almost nothing to do with the present situation.
My sense of the ** present ** situation is that we are going for a precision landing, within one meter of the target.
The customer is going to pay for the lander to show up at the designated spot, so any mass that is needed to insure that result needs to be allocated.
The insurance policy may ripple back up the chain to decrease the total number of landers that can be launched on either a Falcon 9 or a Falcon Heavy if our sales presentation is ** really ** successful. My recommendation is to go for the maximum demonstration of accuracy, reliability and performance, even if it means the total number of landing sites studied is reduced by one or two.
Page 6 passes muster, except that I have invited kbd512 to examine the calculations.
Page 7 the same as 6
Page 8 the same as 6
Congratulations on your work to this point.
Best wishes for continued improvement right up to the ship date!
As a reminder to all.... while the present activity is being developed for a small set of potential customers, there is absolutely **NO** reason why a forum member from a country other than the US can't bring this activity to the attention of the respective, President, Prime Minister, or other High Office, to see if their Nation might want to become the funder for this enterprise.
I'd ballpark the cost at $300MM (US) just to put some heft into the discussion.
A Falcon Heavy is (reported to be) $150,000,000 or so.
I'm guesstimating the cost of the payload preparation at $150,000,000, although that number might be low for 12 landers.
We have members from Canada, the UK, the Netherlands, from Spain, Italy, Mexico and Germany. (please post if I've missed anyone!)
Any ** one ** of the members from those Nations has exactly the same capability (in a free state) to write a letter to the political leadership to encourage their consideration of this opportunity.
I'd like to have a funder at the required level confirmed by the end of October, 2021 at the latest.
If anyone actually follows through on the call for participation given above, have the representative from your Nation contact the Lander Team via the NewMars portal. See Post #2 of Recruiting for details.
Edit: The number of Falcon Heavy systems that can be built and ready for launch by September of 2022 is certainly limited. The first Nation (or corportation) to make a valid offer to make the needed investment would (presumably) be first in line to request a slot in the launch schedule.
On the ** other ** hand, SpaceX might be willing to allocate the resources needed to build more than one Falcon Heavy if the funds are confirmed up front.
There is **absolutely** no need for individual Nations in the European Union to defer to ESA for permission to fund one of these probes.
If a Nation can put up $300MM(US) then they have as much right as anyone else to compete for the naming rights of the first landing pad on Mars.
(th)
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tahanson43206,
Regarding cross-checking of the mass / force figures exerted on Page 6, final mass numbers for Starship are speculative in nature. The design is still being iterated and refined. The force exerted on the ground by either the largely inert or fully loaded vehicle is therefore unknown, because I don't know what landing gear design they're using, meaning no clue about landing pad surface area, nor final descent rate, which will greatly affect the force exerted, not that I expect that figure to exceed the force exerted by the fully loaded vehicle. We can use GW's ballpark numbers, which is what GW has done to illustrate the forces involved. The given mass figures for vehicle payload, inert structure, and propellant come from publicly released information from SpaceX, and corresponds with what I have read.
My cross-check of GW's Earth weight figures given in MegaNewtons, are spot-on with his, and by doing the calculations, I can see that he rounded to 2 digits of precision, which is fine. My Mars weight figures, in MN, vary slightly, but I believe it's down to rounding there as well.
So... Were the Mars weight figures, as given in MN / MegaNewtons, correct?
I'm not sure why I should be the one to double-check what an aerospace engineer did using hand calculations, unless we're short of aerospace engineers, but fine, let's double-check:
Mass = m
Acceleration = a
Weight = w = m * a (mass multiplied by acceleration rate), and therefore m = w / a
N = Newtons
MN = Mega Newtons (1,000,000 Newtons)
gravitational acceleration constant for the surface of Earth is equal to 9.807m/s^2
gravitational acceleration constant for the surface of Mars is equal to 3.721m/s^2
1 MN = 101.9716212978 tons-force (in metric tons, 1 metric ton being equal to 1,000kg)
1.054MN = 107.4780888478812 tons-force (on Mars, according to what we're claiming in the proposal)
Mars gravitational acceleration is 37.94% of Earth's gravitational acceleration: 3.721 / 9.807 = 0.379422861221576
Edit: What's shown below is Starship's mass, which doesn't change, no matter what the local gravitational force happens to be, which is different from weight, which is affected by gravitational acceleration
Starship's mass: 1,054,000N / 3.76m/s^2 = 280,319kg = 280.319t
280t * 0.3794 (37.94% of Earth's gravitational acceleration constant) = 106,353kg = 106.353t = 1.0429666475MN
In the proposal draft, GW said Starship's (edit #2: weight, not mass) was equivalent to 1.054MN or 107.478t at time of landing on Mars. I'd say that's a pretty close estimate, with rounding accounting for the slight variance between his figures and mine. That 1 extra ton is a meaningless (less than 1%) difference, given the force involved. It's better to be slightly over, and if Starship winds up being heavier, then these calculations have to be reworked. The salient point is that, that force is bearing down on the regolith, if the compaction of said regolith is insufficient to support a specific number of tons-force per unit area, then the ground gives way underneath and Starship will topple over unless the geometry of the landing gear provides sufficient stability to account for the settling variations of the landing pads. Given the fact that human lives will be at stake, in addition to the extreme cost of the vehicle and mission, this is never something we want to guess at.
Last edited by kbd512 (2021-09-22 15:44:27)
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The MER aeroshell is to small to add any sort of an engine deceleration to its sled that its riding on.
http://www.ssdl.gatech.edu/sites/defaul … 13-438.pdf
PRECISION LANDING AT MARS USING DISCRETE-EVENT DRAG MODULATION
How the rover is package for the ride from Earth to Mars
Edit image page
https://www.planetary.org/space-images/ … p_03pd1764
Packed rover inside the air bag unit which has the sled for the rover to set on
MER Rover instrumentation
TH. I am sending you dimensioned image of the aeroshell plus
Remember the MER was the only thing inside the aeroshell so its going to need a large shell to fit what we desire inside it
Or its multiple launch time....
The draft 8 along with others put a bad spin on space x coming up with a rover without nasa to build or design it.
Granted Nasa has the right stuff but if we want them to do a design it would not hurt to not directly state that nasa jpl must do so....
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For SpaceNut re #198
The launch vehicle for MER-B was a Delta II "Heavy"
How does that vehicle compare to Falcon 9 or Falcon Heavy?
I asked Google for help and learned that Delta II had a diameter of 2.44 meters.
That might not have been the diameter of the vehicle you showed in the post above.
Falcon 9 payload fairing has a diameter of 5.2 meters and is 13 meters tall.
Please recompute the dimensions of the proposed Mars Landing Pad Probes in light of this difference.
There should be plenty of room for the tractor tower for the drill, and potentially room for up to four landers in one Falcon 9.
There should be room for more than four lander packages in Falcon Heavy.
(th)
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For SpaceNut re stacking probes in Falcon 9 or Falcon Heavy
Something else to add as you carry out your investigation is that the probes do not need to be stacked side by side.
They can be staggered so that more can be fit into the available fairing space.
Plus! There is no reason that the fairing that is standard right now cannot be increased in diameter for a special load, which this would be.
GW Johnson would like to launch enough probes to visit each of the ? 12 ? proposed landing sites.
With a bit of thought and 3 Dimensional jigsaw puzzle configuration, you might be able to fit all 12 with their tractor towers into the Falcon Heavy.
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