
NASA Designed a Low-Tech Rover to Survive Venus - sprucely
https://www.wired.com/story/nasa-low-tech-rover/
======
curtis
I find the idea of an essentially clockwork rover really interesting but from
a practical standpoint I still think the ideal rover for Venus would be like a
cross between an submersible and an airship.

When the rover starts to run out of coolant it would inflate the airbag, rise
up to about the one atmosphere level (50km?), use solar power to replace the
coolant, then descend again for another ground mission. And since the venusian
atmosphere is about 5% nitrogen, nitrogen seems like the ideal coolant, and,
on top of that, it's probably the ideal lift gas for Venus as well. This is
because pure gaseous nitrogen is considerably less dense than gaseous carbon
dioxide.

~~~
jychang
Uhh, an airship? On a planet with winds at 350kmph?

That sounds like a horrible idea.

~~~
elihu
According to wikipedia, winds are pretty slow near the surface. Strong winds
at high altitudes might be a problem if there's turbulence, but if there isn't
it's probably okay.

> Thermal inertia and the transfer of heat by winds in the lower atmosphere
> mean that the temperature of Venus's surface does not vary significantly
> between the night and day sides, despite Venus's extremely slow rotation.
> Winds at the surface are slow, moving at a few kilometres per hour, but
> because of the high density of the atmosphere at the surface, they exert a
> significant amount of force against obstructions, and transport dust and
> small stones across the surface. This alone would make it difficult for a
> human to walk through, even if the heat, pressure, and lack of oxygen were
> not a problem.

...

> The only appreciable variation in temperature occurs with altitude. The
> highest point on Venus, Maxwell Montes, is therefore the coolest point on
> Venus, with a temperature of about 655 K (380 °C; 715 °F) and an atmospheric
> pressure of about 4.5 MPa (45 bar).

...

> Strong 300 km/h (185 mph) winds at the cloud tops go around Venus about
> every four to five Earth days.

[https://en.wikipedia.org/wiki/Venus#Atmosphere_and_climate](https://en.wikipedia.org/wiki/Venus#Atmosphere_and_climate)

Given the thickness of the atmosphere, maybe the most sensible form of
locomotion on the surface is to just let the wind carry you along...

~~~
kruczek
>> despite Venus's extremely slow rotation

That got me curious how slow Venus rotates and apparently it takes 243 Earth
days for a single day to pass there. Which is even more amazing considering it
takes Venus only 224 Earth days to orbit Sun - a single day there takes more
than 1 year! Developing inter-planetary software would have interesting
surprises...

------
aedron
I am always amazed by the images the USSR missions were able to send back from
the Venus surface in the freaking 70's and early 80's [1][2]. For a very long
time that were the only 'real' pictures from another planet. So good looking
and from such a hostile environment.

[1]
[http://mentallandscape.com/C_Venera_Perspective.jpg](http://mentallandscape.com/C_Venera_Perspective.jpg)

[2]
[http://mentallandscape.com/C_CatalogVenus.htm](http://mentallandscape.com/C_CatalogVenus.htm)

~~~
ajsalminen
Viking 1 photographed Mars before this.

------
mturmon
Press release with a bit more on the design:

[https://www.nasa.gov/feature/jpl/a-clockwork-rover-for-
venus](https://www.nasa.gov/feature/jpl/a-clockwork-rover-for-venus)

The WIRED article has errors. They got the PI's name wrong. They also say this
about communications:

"the Venus rover will use a simple optical reflector to transmit its data to
orbiting satellites by flashing radar light like morse code"

This is misleading in a couple of ways. The rover in the link above appears to
use radar targets which turn on wheels; an orbiter would bounce radio off the
target to determine their configuration.

~~~
yincrash
A better analogy might be that it's akin to signal flags.

------
shookness
I used to do research in a lab which studied extreme temperature electronics
using Silicon Carbide CMOS. These electronics are able to handle over 450 C
ambient temperatures and may be able to survive in the Venusian atmosphere
with minimal shielding. Looks like they started a company and have funding for
jet engine electronics.

[http://news.uark.edu/articles/39133/ozark-integrated-
circuit...](http://news.uark.edu/articles/39133/ozark-integrated-circuits-
receives-750-000-award-from-air-force) [http://www.ozarkic.com/our-
services/high-temperature/](http://www.ozarkic.com/our-services/high-
temperature/)

------
dzdt
See this page on extreme temperature electronics for a good discussion of what
is available on the electronics side. The short answer is, there are discrete
components that have been demonstrated to temperatures higher than Venus's
460C but little commercially available. In particular no integrated circuits.
[http://www.extremetemperatureelectronics.com/tutorial1.html](http://www.extremetemperatureelectronics.com/tutorial1.html)

------
donquichotte
> [The new rover] is a great example of counterintuitive problem solving.
> Instead of packing high-tech electronics into its frame, the scientists are
> building a mechanical rover that works with minimal electronics.

Really? Is that counterintuitive? If you talk to car or motorcycle overland
travellers who traverse deserts and remote mountains, you'll find a preference
for simple designs that minimize part counts and electronics (for fuel pump,
ABS, suspension...) to improve reliability, often at the cost of performance
and efficiency.

------
bad_alloc
This is a great example of space exploration that could produce technology
relevant for applications on Earth: If you have a complex machine that can do
usefuk work on Venus, you can use a similar concept for ultra-durable
equipment here. Stuff like this could be relevant for deep sea exploration,
nuclear applications, mining and so on.

~~~
holmak
Why not just design for deep sea exploration or nuclear applications directly?
It's a heck of a lot cheaper to test prototypes in the ocean than on Venus.

~~~
wallace_f
If your objective is space exploration, the poster is just saying it's a good
example of how positive externalities can easily come from it.

------
nradov
We previously discussed an IEEE Spectrum article on the same rover.

[https://news.ycombinator.com/item?id=14965655](https://news.ycombinator.com/item?id=14965655)

------
baybal2
Just don't put a lens cap on it.

~~~
DanBC
It's a shame you got downvoted, because lens caps were really tricky on the
Russia landers.

[https://en.wikipedia.org/wiki/Venera#Venera_camera_successes...](https://en.wikipedia.org/wiki/Venera#Venera_camera_successes_and_failures)

> The Venera 9 and 10 landers had two cameras each. Only one functioned
> because the lens covers failed to separate from the second camera on each
> lander. The design was changed for Venera 11 and 12, but this change made
> the problem worse and all cameras failed on those missions. Venera 13 and 14
> were the only landers on which all cameras worked properly; although
> unfortunately, the titanium lens cap on Venera 14 landed precisely on the
> area which was targeted by the soil compression probe.

~~~
baybal2
Yes, the issue was stupidly trivial. They put a very tight fitting steel cap
on an aluminium camera housing.

They attempted to over-engineer the thing further by adding explosive bolts to
it. That also ended in failure (explosives failed to explode as they
decomposed long before they were fired).

Finally, a dumb solution was devised: to make the cap to fit inside the bezel
and be made from titanium. That finally solved the issue.

As the aluminium bezel expanded, the cap loosened up, falling out under its
own weight.

But that didn't account for another instrument sampling area being right under
the camera, where the cap were to fall.

------
interfixus
Venus is so strangely ignored and forgotten. Measured against the attention
other planets are getting, an orbiting reconnaissance platform with a handfull
of atmosphere and surface probes would seem long overdue.

~~~
rdtsc
Well one reason is because it's so hot there there is almost no chance to find
life or to build a station there. Also I wonder if it is because the Russians
set to explore it, landed a probe on it and all. So maybe then it became
uninteresting to follow in their footsteps. Just like the Russians stopped
sending rovers to the moon once Americans landed there.

~~~
gambiting
It has the interesting property of about 50km above the surface being the only
place in the solar system - other than Earth obviously - where a human being
could survive without a space suit, just with an oxygen supply. The pressure
and temperature are exactly like on a normal Earth day(1atm and around 0-20C).
Floating barges high up in Venus atmosphere have been suggested previously.

~~~
turk184
Does that not consider all the sulfuric acid or is that not a problem at the 1
Bar altitude?

------
kwoff
It's this kind of research into extremes that drives technology forward. Let's
explore Venus!

------
phkahler
This caused me to search for very high temperature semiconductors. It turns
out there are some rated for 300 to 400C operation. This mission seems to
require 450C+ but that's close. This seems like another area where RISC-V
would be very beneficial, as the companies that make very high temperature
chips could benefit greatly from an open instruction set with simple free
designs. One company had 8051s rated over 200C, but that arch is a bit dated.

~~~
ars
I wonder if it would be easier to find discrete components that work at high
temperature. And use a vacuum tube instead of a transistor - vacuum tubes can
handle high temperature easily.

Put all of them in a single strong container instead of using lots of fragile
glass in a high pressure environment. And you won't need to heat the emitter,
saving weight.

~~~
libria
To hell with it. Let's just ship it with a miniature Babbage engine and
finally give it the practical application it deserves.

~~~
TheOtherHobbes
Perhaps there are environments where life evolved to use mechanical instead of
biochemical computation.

If there are, it might feel completely at home on Venus.

------
ChuckMcM
Who knew steam punk would come in handy :-) Seriously though it is an
excellent thought experiment to design a purely mechanical rover. The concept
of using a windmill to wind a spring is pretty neat, although at 850 degrees
its going to be a challenge to find a spring material.

~~~
dsfyu404ed
>although at 850 degrees its going to be a challenge to find a spring
material.

Google "Exhaust heat riser"

A spring that provides many years of useful service when exposed to high
temperatures isn't a very exotic part. NASA probably isn't trying to make it
go 5yr/50,000mi without failing so they can probably come up with something
that works well for the duration of the mission.

~~~
ChuckMcM
Although most heat risers seem to simply be a bi-metal allow which changes
shape when hot. The article discusses winding springs much like a clock maker
would use.

That said, a bit of searching did find Iconel 718 springs which are good up to
1000 degrees. Not a lot of margin but probably workable. Since people has
developed techniques for 3D printing Iconel 718 it seems like that problem at
least is workable.

[1]
[https://www.youtube.com/watch?v=qNk_T82iuHM](https://www.youtube.com/watch?v=qNk_T82iuHM)

------
crispyambulance
I thought one idea for Venus was to have a balloon with a gondola that would
float high in the atmosphere, that way it wouldn't have to handle extreme
temperature and it would just need to deal with the occasional sulfuric acid
thunderstorm!

~~~
rdtsc
I heard that but then I wonder how much better is that than just a space
station.

------
skykooler
> Those treads are powered via a wind turbine that captures the planet’s
> whipping wind gusts

This seems odd to me - Venus has high wind speeds in the upper atmosphere, but
on the surface the winds are only one or two m/s. Is that enough to wind a
spring?

~~~
philipkglass
Yes, because atmospheric density at the surface of Venus is 67 kg/m^3m, about
55 times as dense as sea level atmosphere on Earth:
[https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Tropospher...](https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Troposphere)

------
narrator
The thing about Venus is why bother colonizing it when deep space is more
hospitable than the planet's surface?

~~~
krallja
Unlike space, Venus is made of large amounts of matter.

------
WillReplyfFood
Why not make the robot a worm, that drills beneath the ground after arriving
in a impactor?

All the samples you need, with only a part of the pressure and none of the
toxic atmosphere?

I know it would not make scenic photos- and take forever to get anywhere- but
it would last.

~~~
masklinn
Digging _machines_ are quite complex and prone to failure (that is one area
where humanity is basically nowhere compared to biologicals), you'd have
trouble exfiltering the information, and packing the analysis ware would be
even more difficult than in a surface rover.

~~~
rtkwe
We are fairly far behind but nature does have it a bit easier because animals
are making much smaller holes through dirt and soil instead of solid rock like
most human tunnels want to go through. Also they can just avoid any
particularly difficult areas and move somewhere else.

------
criddell
Did ancient Earth have a more Venus-like atmosphere? If not, what's
responsible for the difference? Is it due to the extra solar energy that Venus
receives?

~~~
brianberns
Runaway greenhouse effect due to high levels of atmospheric CO2.

~~~
criddell
Does that also explain the corrosive nature of the atmosphere?

~~~
mturmon
Short story is that the well-known sulfuric acid clouds are produced by
plentiful CO2 combining in the atmosphere with trace SO2 and H2O gases. The
high temperatures prevent the CO2 and SO2 from being captured into minerals,
as they are on Earth. More:

[https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Clouds](https://en.wikipedia.org/wiki/Atmosphere_of_Venus#Clouds)

------
Animats
Maybe it can rove around on wind power and gears, but if it can't send
pictures back, it's going to be a disappointment.

------
api
I wonder if a vacuum tube computer could survive Venusian temperatures if it
was built out of the right materials?

~~~
turk184
I don't think vacuum tubes would be better than solid state electronics at
those high pressures.

