IPB

Welcome Guest ( Log In | Register )

3 Pages V   1 2 3 >  
Reply to this topicStart new topic
"Dragonfly" Titan explorer drone, NASA funds Johns Hopkins University Applied Physics Laboratory (APL)
Jaro_in_Montreal
post Dec 20 2017, 09:04 PM
Post #1


Junior Member
**

Group: Members
Posts: 60
Joined: 3-August 12
Member No.: 6454



Is there a specific website for this Johns Hopkins University Applied Physics Laboratory (APL) concept for a Titan explorer drone?
Looks to be an RTG powered machine, somewhat reminiscent of MSL Curiosity (RTG sticking out the tail end).
But no camera mast, ChemCam, or sampling arm visible in the concept illustration.

QUOTE
Dec. 20, 2017
RELEASE 17-101
NASA Invests in Concept Development for Missions to Comet, Saturn Moon Titan
Dragonfly
Dragonfly is a drone-like rotorcraft that would explore the prebiotic chemistry and habitability of dozens of sites on Saturnís moon Titan, an ocean world in our solar system.
Elizabeth Turtle from the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, is the lead investigator, with APL providing project management.


https://www.nasa.gov/press-release/nasa-inv...turn-moon-titan

Attached Image

Go to the top of the page
 
+Quote Post
elakdawalla
post Dec 20 2017, 09:33 PM
Post #2


Administrator
****

Group: Admin
Posts: 5083
Joined: 4-August 05
From: Pasadena, CA, USA, Earth
Member No.: 454



dragonfly.jhuapl.edu


--------------------
My blog - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
Go to the top of the page
 
+Quote Post
rlorenz
post Dec 22 2017, 01:22 AM
Post #3


Member
***

Group: Members
Posts: 465
Joined: 23-February 07
From: Occasionally in Columbia, MD
Member No.: 1764



QUOTE (elakdawalla @ Dec 20 2017, 04:33 PM) *


Note especially the quite detailed article that went online there this morning.(jump/scroll to resources)
Go to the top of the page
 
+Quote Post
Julius
post Dec 22 2017, 03:55 PM
Post #4


Member
***

Group: Members
Posts: 309
Joined: 13-April 06
From: Malta
Member No.: 741



This mission should easily top the list. Titan here we come! cool.gif
Go to the top of the page
 
+Quote Post
Y Bar Ranch
post Dec 29 2017, 10:45 PM
Post #5


Junior Member
**

Group: Members
Posts: 37
Joined: 28-July 07
Member No.: 2984



I use Titan as a case study for an aero class I teach, and am super-psyched at the idea of such a probe. Low gravity and high density are a rotorcraft's best friends.

Already drooling over the detailed 3D photogrammetry extracted from aerial images.
Go to the top of the page
 
+Quote Post
vjkane
post Dec 30 2017, 05:39 AM
Post #6


Member
***

Group: Members
Posts: 506
Joined: 22-April 05
Member No.: 351



QUOTE (Julius @ Dec 22 2017, 07:55 AM) *
This mission should easily top the list. Titan here we come! cool.gif

The science for a comet sample return is very compelling (as is the science for Dragonfly; it comes down to do you prefer a great apple or a great banana?).

And I'd never bet on an easy competition with any proposal lead by Squyres, and he's devoted much of his time the last three years putting his comet sample return proposal together.


--------------------
Go to the top of the page
 
+Quote Post
Julius
post Dec 30 2017, 12:23 PM
Post #7


Member
***

Group: Members
Posts: 309
Joined: 13-April 06
From: Malta
Member No.: 741



QUOTE (vjkane @ Dec 30 2017, 06:39 AM) *
The science for a comet sample return is very compelling (as is the science for Dragonfly; it comes down to do you prefer a great apple or a great banana?).

And I'd never bet on an easy competition with any proposal lead by Squyres, and he's devoted much of his time the last three years putting his comet sample return proposal together.
. No disrespect to Squyres, but I can already imagine drone flying over titan lakes and magic Island plus extra miles of vistas to image and investigate. This is too good to let go and yes to me is definitely more compelling than the comet sampling mission.
Go to the top of the page
 
+Quote Post
mcaplinger
post Dec 30 2017, 04:52 PM
Post #8


Senior Member
****

Group: Members
Posts: 1721
Joined: 13-September 05
Member No.: 497



I share everyone's excitement, but we are unlikely to get a lot more public information about either of these missions before the downselect, and the decision isn't made based on popularity. You can go back historically and look at which missions were competing and which were selected, but even if there are clear patterns there, that's not a great indication of future decisions.


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post
Jaro_in_Montreal
post Dec 30 2017, 05:30 PM
Post #9


Junior Member
**

Group: Members
Posts: 60
Joined: 3-August 12
Member No.: 6454



QUOTE (Julius @ Dec 30 2017, 12:23 PM) *
I can already imagine drone flying over titan lakes and magic Island plus extra miles of vistas to image and investigate.


From the description of Dragonfly in http://dragonfly.jhuapl.edu/docs/DragonflyTechDigestAPL.pdf it would not be able to go anywhere near the polar lakes region, landing instead in the equatorial dune fields.

QUOTE
Although the exploration of Titanís seas had previously been considered, notably by the APL-led Titan Mare Explorer (TiME) Discovery concept, the timing mandated by the announcement of opportunity precluded such a mission.
Specifically, with launch specified prior to the end of 2025, Titan arrival would be in the mid-2030s, during northern winter.
This means the seas, near Titanís north pole, are in darkness and direct-to-Earth (DTE) communication is impossible.


Like TIME, Dragonfly also proposes direct-to-Earth (DTE) communication.

Maybe a south-polar visit might be feasible ? ....Ontario Lacus ??

Attached Image

Go to the top of the page
 
+Quote Post
mcaplinger
post Dec 30 2017, 06:03 PM
Post #10


Senior Member
****

Group: Members
Posts: 1721
Joined: 13-September 05
Member No.: 497



QUOTE (Jaro_in_Montreal @ Dec 30 2017, 09:30 AM) *
Maybe a south-polar visit might be feasible ? ....Ontario Lacus ??

From the article:
QUOTE
Arrival at Titan in the mid-2030s with DTE communication suggests a low-latitude landing site. This
requirement means a similar location and season to the Huygens descent in 2005, so the wind profile and
turbulence characteristics measured by the Huygens probe are directly relevant. Furthermore, the sand
seas that girdle Titanís equator are both scientifically attractive and favorable in terms of terrain characteristics for landing safetyóindeed, it was for these reasons that the 2007 Flagship Study identified these dune fields as the preferred initial target landing area.


And it's unlikely that the vehicle will have enough range to fly from equator to pole.


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post
vjkane
post Dec 31 2017, 02:12 AM
Post #11


Member
***

Group: Members
Posts: 506
Joined: 22-April 05
Member No.: 351



QUOTE (mcaplinger @ Dec 30 2017, 10:03 AM) *
And it's unlikely that the vehicle will have enough range to fly from equator to pole.

I'm not so sure. Assume that Dragonfly lands exactly at the equator. The north pole (and the lake region begins before this) is 4044 km away. Assume that Dragonfly has had a great prime mission and the team is willing to just push it to go the distance. At 40 km per hop once every Titan day (~16 Earth days), the north pole is 4.4 years away.

Given that Titan is pretty benign, once you've solved the problem of how to stay warm (always take your warm MMRTG with you when you visit), the limiting factor on the mission may well be how long the the MMRTG power lasts given radioactive decay.

This map in this conference abstract suggests targets that might be in the range of a primary or a first extended mission.

LPSC 2017 abstract



--------------------
Go to the top of the page
 
+Quote Post
Explorer1
post Dec 31 2017, 02:55 AM
Post #12


Senior Member
****

Group: Members
Posts: 1534
Joined: 13-February 10
From: Ontario
Member No.: 5221



Opportunity certainly went beyond its designed range, I wouldn't be surprised that a flying vehicle could go so much farther.
I would be more worried that perhaps the environment isn't so benign; Oppy dealt with dust storms, but what about possible flash floods (as the Huygens landing site showed)? Without weather observations from orbit, that would be a nasty surprise outside the equatorial dune seas! Or the rotors' reaction to giant raindrops in-flight....
Go to the top of the page
 
+Quote Post
nprev
post Dec 31 2017, 09:31 AM
Post #13


Senior Member
****

Group: Admin
Posts: 8095
Joined: 8-December 05
From: Los Angeles
Member No.: 602



I wonder how effectively it could navigate over long distances. We don't have nearly good enough surface maps for AI terrain recognition, there's no significant magnetic field, so all that's left is inertial. Maintaining a good heading alignment over long periods may be problematic since IMUs do have inherent drift, and though periodic realignment is the usual method to correct that Titan's outer shell rotation seems to vary significantly in comparison to the rest of the moon's mass (not sure if that's a fixed offset or variable), and measuring rate & direction of rotation after vertical alignment is the usual method of finding true north (and latitude).

This could possibly be augmented by RDFing the vehicle's downlink to Earth, but not sure how much position precision could be achieved...tens/hundreds of km? Then again, maybe the position of the Sun could be used as well, foggy though it's gonna be. Dunno if Saturn would be detectable, but the Sun's definitely gonna be the only possible reference star.


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post
HSchirmer
post Dec 31 2017, 02:36 PM
Post #14


Member
***

Group: Members
Posts: 331
Joined: 24-July 15
Member No.: 7619



QUOTE (nprev @ Dec 31 2017, 09:31 AM) *
We don't have nearly good enough surface maps for AI terrain recognition, there's no significant magnetic field, so all that's left is inertial.


Not necessarily, just old-school triangulation: "1800s mountain peak GPS", using trigonometry to track where the mountain peaks are on the horizon.

Ala "the Englishman who went up a hill, but came down a mountain" you build up a triangular grid of the highest points by surveying.
That lets you triangulate your map location, and calculate your height, based where they are on the horizon.
Go to the top of the page
 
+Quote Post
RoverDriver
post Dec 31 2017, 04:25 PM
Post #15


Member
***

Group: Admin
Posts: 932
Joined: 29-September 06
From: Pasadena, CA - USA
Member No.: 1200



QUOTE (nprev @ Dec 31 2017, 01:31 AM) *
...
but the Sun's definitely gonna be the only possible reference star.


The nadir vector can be detected by the accelerometers. The Mars rovers we use: clock, Sun position, and nadir vector. As an alternative gyro compassing might be quite more difficult but not impossible.

Paolo


--------------------
Disclaimer: all opinions, ideas and information included here are my own,and should not be intended to represent opinion or policy of my employer.
Go to the top of the page
 
+Quote Post

3 Pages V   1 2 3 >
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 15th August 2018 - 08:36 PM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.