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ЦитатаInSight mole making slow progress into Martian surfaceby Jeff Foust -- May 5, 2020Recent images from NASA's InSight Mars lander show the lander's robotic arm, with a scoop at the end, pushing down on top of the mole as it attempts to burrow into the surface. Credit: NASA/JPL-CaltechWASHINGTON -- An instrument on NASA's InSight Mars lander that has struggled for more than a year to make its way into the Martian surface is now making steady, but slow progress with the help of the lander's robotic arm.The Heat Flow and Physical Properties Package instrument on the InSight lander was to deploy a probe, or "mole," into the surface of the planet, using a hammering mechanism to burrow as deep as five meters below the surface to measure the heat flow from the planet's interior. The probe, though, got stuck shortly after it started burrowing in February 2019, getting no deeper than about 30 centimeters.The project has tried several ways to get the mole moving into the surface again. Most recently, spacecraft controllers positioned the scoop on the end of the lander's robotic arm on top of the mole, pushing down on it to help it move into the surface and to prevent it from moving back out, which has happened in the past.That approach is working so far. "The mole is going down by its hammering mechanism, but it is aided by the push of the scoop that balances the force of the recoil," said Tilman Spohn, principal investigator for the instrument at the German space agency DLR, during a May 4 webinar about results from the mission that was part of the European Geosciences Union General Assembly, a conference that moved online because of the coronavirus pandemic.However, the progress is slow because of the need to reposition the arm as the mole gets deeper. "That is a very tedious operation," he said. "We can only go like 1.5 centimeters at a time before we have to readjust."Another issue is the angle at which the mole is penetrating into the surface. The mole was originally designed to go down vertically, but is now at an angle of nearly 30 degrees from the vertical. "It's not something we like to see," he said. If the mole is able to get completely below the surface, he expects that it will "rectify itself to some extent."The problems have given scientists some insight into the properties of the surface at InSight's landing site. There is a "duricrust" about 20 centimeters thick, which he described as sand that has been cemented into place by salt. That duricrust didn't provide enough friction to keep the mole from recoiling as it tried to hammer into the surface initially.Another issue, he said, is that there is now a region of compacted sand created by the mole as it hammered in place without moving deeper. That will make it more difficult for the mole to penetrate into the surface, even with the assistance of the robotic arm.While Spohn didn't state how long the current effort to get the mole into the Martian surface would last, other project officials have suggested it may take a couple months. The latest effort had just started when Bruce Banerdt, principal investigator for the overall mission, gave a briefing at a meeting of NASA's Mars Exploration Program Analysis Group April 17, noting that the lander's other instruments, including its seismometer, were working well."We anticipate that we'll have the mole down flush with the ground within another month or two months," he said. By then, the arm will no longer be able to help push the mole further into the ground. "At that point, it's either going to be able to go on its own or not."
Цитата: undefined03. June 2020 | posted by Tilman SpohnThe InSight mission logbook Credit: DLR (CC-BY 3.0)You can find more graphics explaining the instruments of the InSight mission on flickrIn his logbook, Instrument Lead Tilman Spohn who is back in Berlin since April and communicating with JPL via the web, gives us the latest updates regarding the InSight mission and our HP3 instrument - the 'Mole' - which will hammer into the Martian surface.Logbook entry 3 June 2020More than three months have passed since my last blog post, when I had to report that the 'Mole' had unfortunately backed out again. Not as much as in October, but nevertheless, after going 1.5 centimetres into the surface, it reversed direction and backed out by 1.5 plus 3.5 centimetres, with the back cap ending a total of approximately five centimetres above the deepest position reached at the time and about seven centimetres above the surface. I described the situation in more detail in my previous post, in which I also detailed how the team attempted to explain the downward and then upward motion during one single hammering session (we had not seen this before).As a consequence of the lack of success with the last attempt at pinning, the team decided to adopt an alternative strategy and try the 'back-cap push' technique instead. For this, the scoop is placed above the back cap and slowly lowered until it touches the cap. The arm is then further lowered and tensioned such that the scoop presses on the Mole with a force of about 50 newtons. When the Mole descends into the surface, the scoop follows its downward motion, but the load decreases as the Mole progresses. After approximately 1.5 centimetres, the pushing force reduces to zero and the push action has to be renewed. Credit: DLRBecause of the orientation of the Mole in the pit and the limited reach of the arm, the scoop touches the back cap close to its edge at more or less a single point. The image below shows the situation as simulated in a laboratory at DLR. This simulation was done to assess how critical the placement was for the tether. As can be seen, an error in placement of just a few millimetres could have either caused the scoop to slip off the back cap or to damage the tether. In addition, as the Mole moves down, the scoop moves to the left relative to the Mole and towards the tether.Therefore, the team proceeded very carefully. After each placement, the situation was checked through imaging and recordings of arm motor current data before a number of hammer strokes were commanded. We started the procedure with only a few (25) hammer strokes. Only after the team had gained some confidence in its ability to carefully place the scoop and in the rate of progress of the Mole did we increase the number of hammer strokes per session to, in the end, 150 strokes per session.As I had reported in an earlier post, the present mode of operation of the InSight mission allows only one cycle of operations per week. (Remember, we are in a phase of the mission when the instruments should be 'monitoring' rather than 'deploying'. In the deployment phase in early 2019, commanding was success oriented - that is, as needed. In the monitoring phase, we have far fewer team members; most have other project commitments.) Thus, placement of the scoop occurred only every other week (mostly on Saturdays), followed by what space engineers call a 'ground-in-the-loop', that is a checking of the placement of the scoop on Mondays to give the go-ahead for the next hammering, usually on the following Saturday.We started about seven centimetres above the surface on Sol 458 (11 March) and we are now at the surface with the scoop on Sol 536 (30 May 30), after six cycles of hammering over 11 weeks. The movie below shows the entire history of penetration through back-cap pushing. Credit: NASA/JPL-CaltechIt is possible that the hammering stopped when the left edge of the scoop was still one millimetre or so above the surface. Also, the scoop is obviously at an angle with respect to the regolith surface, such that the right edge of the scoop may still be a centimetre or so above the surface. In addition, we know that the surface is covered with about one centimetre of relatively loose sand that the scoop may compress.Therefore, the next step will be another hammering with the scoop pushing on the back-cap. During that hammering, we expect the scoop to be stopped by the regolith (if it has not been stopped already at the end of the Sol 536 hammering) and we can see whether the Mole is able to dig on its own. We call this the 'free-Mole' test.Clearly, the Mole was not stopped by a stone as has been suggestedYou may recall that our leading theory was that the Mole did not move into the subsurface because the regolith did not provide enough friction to balance the recoil force of the Mole. Although this force is much smaller than the force that drives the Mole forward (five to seven newtons as compared to 900 newtons) it still needs to be provided by the overburden pressure. Calculations that I had discussed earlier in this blog suggest that the friction force will suffice if the Mole is fully buried. Some additional friction can be provided if we use the arm to load the surface, which we will do.Should the Mole move into the subsurface on its own (albeit being helped somewhat by the regolith push), friction will increase and improve the situation as the Mole moves deeper. When the Mole back cap is at a depth of approximately 20 centimetres, loading the surface will have become ineffective and the regolith push should no longer be necessary. We will then do what we planned to do more than a year ago - command the Mole to hammer to depth.So, you see, the next step, the free Mole test, will be very exciting. But what if the Mole is just not deep enough in for sufficient friction? We then have two options, either fill the pit to provide more friction and push on the regolith, or use the scoop to push at the back-cap again, but this time with its tip rather than with its flat bottom surface. This would be a somewhat more difficult operation but doable, as the Instrument Deployment Arm (IDA) team thinks.In addition, winter is approaching on Mars' northern hemisphere and dust storm season will begin soon. The atmosphere is already getting dustier and the power generated by the solar panels is decreasing. This may affect our ability to performing energy consuming operations with the arm in the near future. Stay tuned and keep your fingers crossed.And, is it not wonderful how people can work together from home across large distances on Earth and to Mars? Thank you very much team!
Цитата: Старый от 04.06.2020 23:31:15До уровня поверхности запихали. Дальше поехал сам? Назад не вылез?
Цитата: testest от 05.06.2020 00:15:03Если нет, то этот ужас закончится.
Цитата: testest от 05.06.2020 00:15:03Цитата: Старый от 04.06.2020 23:31:15До уровня поверхности запихали. Дальше поехал сам? Назад не вылез?Не поехал еще. Они только готовятся провести пробное включение, чтобы понять - сможет он погружаться самостоятельно или нет. Если нет, то этот ужас закончится.
Цитата: opinion от 06.06.2020 00:08:57И написано, что из-за того, что миссия в стадии наблюдений, а не развертывания, они могут работать с аппаратом только раз в неделю. Один сеанс связи на перемещение совочка, один на верификацию, что попал куда надо. Итого две недели на каждую операцию.
Цитата: Alex_II от 06.06.2020 19:44:39Всемогущие автоматы...
Цитата: Старый от 08.06.2020 16:12:21Я вот не понял: почему они боковым движением ковшика не поставили крота вертикально?
Цитата: undefinedJuly 7, 2020NASA's InSight Flexes Its Arm While Its 'Mole' Hits PauseThe movement of sand grains in the scoop on the end of NASA InSight's robotic arm suggests that the spacecraft's self-hammering "mole," which is in the soil beneath the scoop, had begun tapping the bottom of the scoop while hammering on June 20, 2020.Credits: NASA/JPL-CaltechNASA's InSight lander has been using its robotic arm to help the heat probe known as the "mole" burrow into Mars. The mission is providing the first look at the Red Planet's deep interior to reveal details about the formation of Mars and, ultimately, all rocky planets, including Earth.Akin to a 16-inch-long (40-centimeter-long) pile driver, the self-hammering mole has experienced difficulty getting into the Martian soil since February 2019. It's mostly buried now, thanks to recent efforts to push down on the mole with the scoop on the end of the robotic arm. But whether it will be able to dig deep enough - at least 10 feet (3 meters) - to get an accurate temperature reading of the planet remains to be seen. Images taken by InSight during a Saturday, June 20, hammering session show bits of soil jostling within the scoop - possible evidence that the mole had begun bouncing in place, knocking the bottom of the scoop.While the campaign to save the mole continues, the arm will be used to help carry out other science and engineering work. Here's what you can expect in the months ahead from the mission, which is led by NASA's Jet Propulsion Laboratory in Southern California.What's next for the mole?The mole is part of an instrument called the Heat Flow and Physical Properties Package, or HP3, that the German Aerospace Center (DLR) provided NASA. While the scoop on the end of InSight's arm has blocked the mole from backing out of its pit again, it also blocks the arm's camera from seeing the mole and the pit that has formed around it. Over the next few weeks, the team will move the arm out of the way to better assess how the soil and mole are interacting.The mole needs friction from soil in order to burrow. Ironically, loose soil provides that friction as it collapses around the mole. But the soil beneath InSight has proven to be cement-like duricrust, with dirt granules that stick together. As a result, recoil from the mole's self-hammering action causes it to bounce in place. So the team's next moves may be to provide that friction by scraping or chopping nearby soil to move it into the pit it's in.More thoughts about the mole's recent progress can be found on a blog written by HP3's principal investigator, Tilman Spohn of DLR.What's next for InSight's arm?InSight landed on Mars on Nov. 26, 2018. Its robotic arm subsequently set HP3, a seismometer and the seismometer's Wind and Thermal Shield on to the planet's surface. While the arm has been key to helping the mole, scientists and engineers are eager to use the arm's camera to pan over InSight's solar panels, something they haven't done since July 17, 2019.It's the dusty season on Mars, and the panels are likely coated with a fine layer of reddish-brown particles. Estimating how much dust is on the solar panels will let engineers better understand InSight's daily power supply.Scientists also want to resume using the arm to spot meteors streaking across the night sky, as they did earlier in the mission. Doing so could help them predict how often meteors strike this part of the planet. They could also cross-check to see whether data from InSight's seismometer reveals a meteor impact on Mars shortly afterward.What's next for the seismometer?InSight's seismometer, called the Seismic Experiment for Interior Structure (SEIS), detected its first marsquake nearly three months after starting its measurements in January 2019. By the fall of 2019, it was detecting a potential quake or two per day. While SEIS has detected more than 480 seismic signals overall, the rate has dropped to less than one per week.This rate change is tied to seasonal variations of atmospheric turbulence, which creates noise that covers up the tiny quake signals. Despite the protective Wind and Thermal Shield, SEIS is sensitive enough that shaking from the wind hitting the shield can make quakes harder to isolate.More About InSightJPL manages InSight for NASA's Science Mission Directorate. InSight is part of NASA's Discovery Program, managed by the agency's Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.A number of European partners, including France's Centre National d'Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain's Centro de Astrobiología (CAB) supplied the temperature and wind sensors.2020-124Last Updated: July 7, 2020Editor: Naomi Hartono
ЦитатаThe new design to be implemented in the flight instrument will compress the hammering springs by 15 mm, resulting in a total hammering energy of 0.83 J for a spring constant of 7.4 N/mm.