NIAC 2021 - Lunar CraterRadio Telescope

Saptarshi Bandyopadhyay

Lunar CraterRadio Telescope (LXRT) on the far side of the moon

Notes by Paul Fischer

Showing with wavelengths are colored 10-100m wavelength band that is 3-30 MHz radio frequency band

Isolation of LCRT from earths noise wavelengths greater than 10 MHz have not been explored by humans, this telescope will measure 3-30MHz

The Moon provides shedding against noise from earth, hence far side

This will be the largest filled aperture telescope in the solar system

The idea has been around since the 1950s

Lunar Arecibo type …

Technical challenges section of lunar craters…

Selection.

Aricebo type

…

…

Selection of image by royal society

1km diameter deployable reflector

Side view of the concept

Philosophical transactions of the royal society…

Hubble looks at the midrange, there is no data on the nature of the cosmic dark ages, this telescope will fill the gap

Nobel prizes on cosmetology - improves on former cosmelogical models

Spatial structure and fluctuations of the redshifted hyperfine transition of hydrogen, like teen meters or more spectral shape and polarization needed to extract the signal are all known

Going towards the left on this plot are supposed to arrive the dotted line is the best astro-free theoretical model, different models have been proposed

This will collect data from the dark ages

This is 5 times greater than the signal used to extract the foreground signal galactic with altitudes on the moon

This cable shows ….

Lunar crater selection there are over 82k craters in just 3-5 km diameter range that are appropriate

We chose the cradter at 9…x169…

Selector wire mesh design is stronger and may be lifted due to low gravity

The spacing must be less than min theta over 4

Variable mass concepts where linear density of cosin … x/ pocosin x

Parabolic mesh equation spans six orders of magnitude, the computational challenge of designing such a mess is tough

Four interdisciplinary constraints: 

Structural and thermal analysis - prove loads and temp data can be survived

Deployment from stored configuration

Radio frequency performance

Launch mass and launch loads

Current work: design reflector that simultaneously satisfies constraints

The gravity and thermal loads are mapped

The change in temperature in the night is only 10K

We chose 16 lift wires …and 4 lift wires…

Next we focus on the RF performance, from 13 MHz …

Understanding the three docs is important

Performance of the periodic antenna will be improved in phase two

Concept of operations

Earth to moon, landing on moon, antenna prep, deployment, data collection….

Three options on the right CONOPS trade space so the decision to use rovers or robots, increased rovers reduces construction time, and the times depend on lighting, terrain and loads

Packaging of reflector

Deploy lift wires

Anchor

Lift and deploy mesh

We went thorugh different options

Quasi static deployment

Final free deployment, each can be used effectively

The wire mesh would be a suitable lunar crater

Q: mechanical challenges to the deployment of the system as a whole? Rovers going out and tension for the cable as a whole, what sort of delivery system will we be looking at?

A: combined masses of 5-6 metric tons, we are keeping an eye out on starship, this has the capability of taking a hundred metric ton payload and this is something we will actively investigate in phase ii

Q: can the parabolic method work in the visible regime?

A: theoretically yes, but you need increased magnification and in practice this would never be useable.

Q: can you talk more about the science objectives here?

A: the neutral hydrogen at 21 cm release of photons, and that has been released say 13 billion years ago, this increases all the way to 10 meters or more. Why are we trying to observe? We really don’t understand dark energy and dark matter, and the rest is all dark energy and dark matter. There should have been more antimatter, and suddenly it vanished, there are lots of cosmological concepts, and we want to collect data that would throw a light at these questions, we would be able to understand these energy changes in our human society, think of a hundred years ago

Q: general speaking about the advantages of a lunar telescope  as oppose to one on earth. The ionosphere blocks these wavelengths and you could potentially put something back on earth and potentially override that over super long periods of time. Even if you want to put something on our topic, with hundreds of meters scale, that is why earth is really not a good idea. The lunar  far side is a great place. Everyone wants to put something on the lunar surface, we would need additional shielding… for most of the orbit there would be exposure to radiation noise from earth. We want to make sure that our research answers one of the big unknowns, but we have remaining questions

Q:what about a rover instead of harpoons or driving through the crater itself?

A: we did not invest in different robot designs, because we already have two miracles in function.

Q: how does the thermal cycle affect the lunar cycle?

A: you do not want the change of the temperature to affect the telescope.

Q: acknowledgements

A: lots of good astronomers on the team

NIAC 2021 - PEDALS

 Patrick McGarey

Notes by Paul Fischer

PEDALS

Passively Expanding Dipole Array for Lunar Sounding

Develop a mission architecture for a low-cost roll- out antenna array to conduct a multi resolution multi path survey of the moons crustal stratigraphy

Multi static radar probing from the regolith through the crust

Better integration time, noise and resolution v SOTA

This is accomplished by … and architecture

Stratigraphy and lateral variations tell the story of lunar formation, volcanic history and evolution and impact history

This instrument should address all aspects of stratigraphy

Configured on the fly for much greater depth than state of the art precedent

Maximum resolution of .5 m can be achieved with Pedals

Penetration depth of greater than 10m depth resolution of one meter

While at greater than 600 meters the depth resolution must be over ten meters

A number of tethers can hold dipole antennas and probe from meters to km in depth, particular aspects of the tether to share

Linear dipoles can be coupled or coliniear for multiple dipoles

No matching circuit is needed

The minimum attena length can allow no further resolution

Combining antenna to change the resonant frequency, it allows the network to tune the frequency of each 

Couple able linear dipoles analysis are demonstrated in models as shown on the right

Different parts of the antennas at different times

Negative or positive instances of reactions, inductive and capacitive reactions on the right

Behavior of the antenna across frequency, now lets consider the methods for deployment

Low mass

Volume efficient

Robust to obstacles

Long distances

The system must be elastic and that means a passive system, like a roll of tape that unrolls naturally, whether we are unrolling or unspooling or unfolding like a scaffold

Ever played with a tape measure and let it rip, the rate limiter or controlled approach 

Stability controls - damping/friction

Contacted by a company that makes coinable booms that loaned  a sample

How likely that pedal will encounter an imassable rock?

Use of a formula to find what number of rocks might represent there

What is the probability for success? Think about it like 100 m

Almost four km or we need to design/plan for obstacle avoidance

Test a coilable boom design from opterus

Q: what are the biggest challenges with obstacle avoidance?

A: the primary thing is that idea of not wanting to avoid rocks, just have this thing happen passively… significantly offset the science goals, for instance use the tape with something like an outrigger vs. the tape just unrolling itself, we would id all of those trades for a future mission

Q: Loop design?

A: same thing, but a substrate of the tether, essentially three tethers where the sun can be used to unroll them, in any geometry that you actually want, even a meter wide. The challenge is how to imprint that loop on that tape vs. tune the frequency… fixed resonant frequency

Q: boom arms is there room for that here?

A: the boom is complementary it is essentially our tape, the idea of reaching our distances is what we are both after, this is where the NIAC community would share our identities and there is encouragement to see what to do next with it

Q: large rocks and according adjustments?

A: a nice way to do it would be to stick the payload on the lunar lander as the train is coming down, no way to stop either of these from happening…

Q: deployment?

A: might be beneficial to have a loop and be with them passively and touch the surface of what these things could do

Q: the way that dipoles and radars work, 

A: if you have a void you have an absence of material and the Pavone mission to explore the lunar cave, we don’t know that it is a cave

Q: goals?

A: cost effective and minimally robust, looking at the lunar swirl area on minor gamma, we want simple awesome science

NIAC 2021 - ReachBot

 Marco Pavone

Stanford University

Notes by Paul Fischer

ReachBot: A Small Robot for Large Mobile Manipulation Tasks in Martian Cave Environments

ASL BDML earth and planetary surfaces group

Problem increasing reach and strength usually scales poorly with mass and complexity

Small robots are limited to small reachable wrkspace and wrench capability

Increasing reach and strength usually scales poorly with mass and complexity

Small robots are limited to small reachable workspaces

Enabling technology including extendable booms as controllable prismatic joints

Solar sails, panels, or camera booths

These booms have strong concise time

These can achieve extreme …

Feasibility challenges

Specific context of a martian cave exploration, focusing on noachian era targets

Maximize reachable and wrench workspaces

Positions shoulders and maintenance…

Creepers must be high weight, and must adapt and be both small and large

Control in motion changing policies

We aim to redeem robust control and motion planning

Finally natural mission for exploration and sampling of martian caves

Reliable lightweight surface grasping solutions

Inspiration from the fee of dexterous directionality

Instead of having fingers, we would use booms that provide pull

First hardware prototype provides unlimited banding and booms for the space structures

Retracting anchor arms allow the booms to provide movement

Early finding from the prototype using force control to prevent buckling and minimize oscillations

System level design considerations , degree of freedom for the consideration of the joints

How reachbot would explore the geometry of the given cave’s geometry

Do feasible trajectories exist then iterate on the process

This process will eventually lead to the second generation

Q: payload

A: the robot will have a number of sensors including cameras and microscopes, this is quite scalable that n engineer is looking at the tradeoffs… the instruments that have been discussed remain a question of tradeoff and imagine cameras and hypo spectral cameras in the near infrared and the thermal infrared miniaturize it enough to fit on the robot

Q: compatible with robotic armor in caves

A: asteroids and comets and in the context of assistance robots for a number of tasks, we are focusing on the caves

Q: grippers for all surfaces or just for rocks?

A: made for rock surfaces and knew that other robotic … had consequences no confinement to working in rocky terrain, in adhesive grippers with smooth materials, terrain such as caves where the competitive advantages such as this can shine, the grippers should be light and take load comparable to what the booms can support, up to tens of kg at most. At the strength of the rock strippers as well… 

Q: rock debris at the spooling of the arm?

A: definitely a big challenge for most concerned explorers, same challenge of dealing with dust and the focus of the investigation it is not, but in the future

Q: booms more efficient from the ground?

A: motivation for the cavelike surfaces is to get up to the ceiling and higher surfaces with less debris

Q: structure overall a tethered unit or stand alone?

A: no tether, carry the subsystems making heavier and in terms of reach and range, currently we are exploring the design phase it could be tethered or untethered

Q: how to determine the appropriate anchor points?

A: the proposed strategy is a semi autonomous one, id candidate grip sites and the idea is to have sensor s at the gripper and see if this is a good feature for grasping. On the control planning and control side, a combination of careful selection of anchors and redundancy like climbers 

It is the nature of this sort of climbing that a sort of grip will fail. Tether can be used a s a structural member and reaches the bottom with the grippers and booms and up towards the walls, an intention to keep the boom as much as possible

Q: how to handle unstable rock grips and pile, is there an autonomous capability?

A: in the end, you don’t really really know just like a rock climber, if it turns out to be loose and it comes off, you would be able to move fairly quickly without a new grip and slowing down the whole process

NIAC 2021 - Ablative Arc Mini In-situ Resource Utilization

 Amelia Grieg U of Texas

Notes by Paul Fischer

Ablative Arc Mini in-situ resource utilization

Using controlled lightening bolts to mine the moon

Two options

Take everything with us

Or find ways to use things there

Propellants, oxygen, and silicon available on the moon

Lunar regolith is composed of many elements and lunar water ice frozen into various points on the moon

North and south lunar poles

Many challenges

Water found in areas permanently shadowed near the lunar pole

No option for high flow rates, and large losses through natural diffusion prices

Very fine and electrostatic lunar dust

The oblique arc mining approach begins with an electric arc and the electrons in the arc will come off in charged form meaning the regolith can be transported with no mining parts

Electric fields minimize losses from natural diffusion and no reliance

Focusing ion optics…

Moving equal velocity is important for the next step, and the beams will pass through a magnetic field through a permanent magnet

The particles will then be placed in a dedicated collection reservoir in direct path of the elements while metals and other solid materials will be placed on a collection plate

Entire system contained in a single skewer crawler

12 electrodes will be placed on the ring in the front

A circular region in front of the ring would be ready for collection and sorting

The arcs no longer reach the surface and begins arcing again

Single arc 1Hz can mine 131 kg per year, while estimates of a full scale mining system would require fore crawlers with 10 metric tons

The axis robotic arm would be the only moving parts other than mobility

Q: how to deal with charged dust particles in the electrostatic?

A: not as bad as much of the lunar dust and the crawler and collection system most will be drawn into the same … looking at a collection reservoir for dust, and the heavy dust particles. Other work has seen the regultih to be used for building materials

Q: how to deal with erosion of the arc electrodes?

A: in the video multiple sets and expansion of the erosion material, the collection materials were also … snap the electrode ring into place and use the same bulk vehicle

Q: how to deal with the oxygen produced?

A: oxygen has not been looked at yet, it is too much on top of everything else, looking at ablation and transport side of things, cryogenic collection of water vapor

Q: Would the process benefit from some sort of ideal feedstock? Are some soils or regolith more suitable for this method than others? 

A: at this moment only a few regolith lunar simulates are available, the highland simulates are better for this particular system, which is all that we have used so far. Different regoliths and see if there are any differences there

Q; by what means would this be able to test the type quantity and charge?

A: the total mass that is ablated, and then a residual gas analyzer works very similarly to the general …. This gives us the relative ratios of the simulates, we also have a spectrometer set up and the products that are being set up as being transported through the chamber, with the three combined we get a good representation of what the arcs are

Q: once sorted, is the material charged first? Maintain the charge of the particles or not?

A: there is no reason to keep the particles in the charged form, that would be collection of the gas

Q: updated numbers as more tests are taken, power vs. how much you are going to be able to mine?

A: that is one of the biggest questions to answer in phase one, the values are still approximations, based on plasma thruster technology, to produce thrust instead of sorting it, slightly bigger for the full scale system, and there is no data on that, but once experimental results are sorted then the results can be updated to be more certain

Q: have you considered applications for the mars surface?

A: slightly higher formation would be easier to apply on mars than the moon even

NIAC 2021 - SCATTER

 Sigrid Close

Stanford University

Exploring Uranus through SCATTER: Sustained ChipSat/CubeSat activity through radiation

Deploy probes through a mothership, tell the difference between something changing in time and something changing in space, and do other things such as communications and use of a laser beam from other ship to power probes

This will allow understanding about sun interactions as well as design smaller probes

Exploring uranus

High priority target and has only been visited by voyager 2

Highly inclined magnetic dipole predicted to undergo rapid reconfiguration with solar wind

Relevant as analogue to similar exoplanets

Long duration mission required to study magnetospheric and plasma dynamics, we hope to deploy probes intermittently…

Scatter concept minimize probe mass using a laser to replace subsystems

PV cells for conversion to DC electricity and a retroreflector for data transfer to mothership with reflectivity control panels for thrust and attitude control

For the laser beam itself, baseline transmitter with diffraction limited parameters of 1 m beam diameter t 1000 km distance peak intensity of greater than 3.7 w/m2 ambient solar out to 2000 km

Membrane concentrated lasers

Increased divergence angle for return beam (smaller aperture)

Probe sizing between five grams to five kg

Lightweight membrane substrate within a carbon fiber circuit board…

Cubesat would include attitude control and payload 

The chipsets would be far more effectiewith SCATTER than with a Cubesat

The life would be short so there is no need to worry about the durability, with self-centering capability focused on the probes themselves.

Actuated through controlled reflectivity panels

Separation rate governed by the ejection speed, no impact on the ability to leave the mother ship up to 1000 km

Within the orbital plane, gravity forces from the sun both remain lower than the sun up to 200 km of separation

SCATTER

Will characterize measurements to texture Uranian magnetosphere enabled by laser driven probes

Powertransfer and comm to…

Q: is the laser beam also being used to encode data into the beam?

A: the idea is to modulate the laser beams within the average. Times that it is turned off we can communicate the same way that laser communication devices do

Q: relation to Nelson and hyperbole objects?

A: as you get closer in, the solar becomes the big tradeoff, if energy is there, what sort of measurements can be made. Looking at alternative methods for power

Q: …

A: based on parameters of communication lasers, the power can be based on sliding nobs to change the ability of the device

Q: reuse?

A: single use, partially because radiation would be something of an issue

Q: could multiple beams form corners of a square or a triangle?

A: keep the beam and the laser emitter fairly simple, rather not deal with a phased array, hopefully looking at a fixed laser beam and see if the probe can fight orbital dynamics/ disturbance forces

Q: is disposable compatible with planetary protection measures?

A: stable vs. unstable manifolds, possibilities to use manifolds to constrain locations of the various probes

Q: radiation question, it still needs to survive to get there?

A: the radiation hardening could be placed on the dispenser, and shielding the more fragile spacecraft, right now with how sensitive the probe is and could be deployed given 5-10 grams if possible based on the chips that have been used in chips

Q: with a 20 watt laser how much power relative to tiny incident of light

A: if we start with something more conventional, we can start with something without much problem and at 1000-2000 km we look at 20-25 watts we look at 25% given the PV cells that we have seen thus far, in terms of the smaller chipsets, we will be capturing more like tens of kw. Some high power applications and designed have been made with cubesat

Q: lots tailored to the design and further applications

A: lots of various applications, in this sense what can and cannot use the laser, from chips to cubesat 

NIAC 2021 - Regolith Adaptive Modification Systems (RAMS)

 Experiment Station

Sarbajit Banerjee, PhD

Davidson Chair Professor of Science, Professor of Chemistry

Notes by Paul Fischer

Regulith adaptive modification systems

Tame the regolith so it does not go flying into plumes on spacecraft

Build up the infrastructure on planetary bodies

Chemistry to make steel and advanced alloys with rgulith along with load bearing dense silicate structures

Microcapsule technologies to position these chemistries at any location

What we had dreamed up in any measure

Hard weight-bearing structures

Delivered thought microcapsules released payload upon impact

Changing infrastructure and how it is built on planetary bodies

Exothermic thermite reactions

Heat thermic reactions

Companion and termal sintering

Make use of source materials for use in the construction of various structures

Built of small razor sharp particles

Pyroxenes iron nickel etc used to make the alloys

Abundant in certain areas across the lunar surface, mapped

The lunar regulith can be combusted using nano molecules

By transitioning magnesium particles and can be brought to the surface to form magnesium oxide as a by product

Thermite reactions can be made and in essence to be burning metal in a small scale thermal reaction against magnesium

Metal oxide provides its own source of oxygen, the light weight and relative reactivity results in a solid chunk of solid regolith possibly accounting for the small strings and the lunar regolith, illmunite could be useful for carrying out thermite to that carries out high strength alloys

A subsurface structure can be performed

As the microcapsules rupture, a series of chemical matrices can be created

Three different precursors have been allowed to fully homogenize and rapidly solidify the mixture Ito a single material and can be pressed into 3d printers or used

Careful preparation of the regolith, microcapsule jetting can be useful for precursor delivery

The custom micro encapsulation system can be velocity dependent delivery and they can be ruptrred and deposited deeper in the precursors

The initial exothermic reaction can be …

Consolidation can be achieved with high strength alloy on top or by creation of slabs

Q: mgO is a common by-product, are there any uses for that?

A: yes you can set up a cycle to recapture the mg again, and this is a resource we will b e able to recover or use for this chemistry, this is something that has been used in parallel, and deal with electro deposition and mg precursors can be made in some sort of an environment with precisely modulated geometries through the thermite reactions

Q: what range of depth would be used for the laser to ignite the reaction?

A: the laser is one method, also with fuel or shock methods. Depending on how deep you want it to go, we have looked at simulated regolith and depending on projection velocity with which we project the microsimulants into the …

Q: wil the thermite reactions react in the same ways?

A: on other planetary bodies and other pesky issues that we have here, but going to space is the way to take this research further. Remember the oxygen is coming form the regulith itself. A fair degree of control over the microstructure and an example of the microstructure itself

Q: findings on thermite?

A: one of the reasons to use this approach, we have worked for years on micro encapsulation which are being loaded by the train carload, and the purpose is to use thermite chemistry in. A safe way, that is the type of microstructure that we want and has the weight bearing properties that we are looking for

Q: martian material sources and how can you know what to look at and where to land?

A: We worked with primarily lunar simulates and we have been very successful with al and ni found, we have had success looking at other types of 

Q: can the released oxygen be used to make thermite?

A: exactly the right way to think about it, using solar power to do electrolysis, and a lead compound…