Entry, Descent, and Landing data |
Entry, Descent, and Landing data |
Jun 1 2011, 10:59 PM
Post
#1
|
||
Junior Member Group: Members Posts: 89 Joined: 27-August 05 From: Eccentric Mars orbit Member No.: 477 |
Poking through the files at JPL NAIF, I found a couple of kernels for MSL. One is labeled cruise, and one is labeled EDL. Now since there is no target set yet, these are obviously preliminary, but they are still interesting for just seeing what EDL is like. this is the comment section of the EDL kernel:
QUOTE MSL Sample EDL Trajectory SPK File (Central Landing Site (0.0 N, 45.0 E) =========================================================================== Created by Fernando Abilleira, MSL MD/NAV. Comments added by Boris Semenov, NAIF/JPL on Tue Feb 23 16:34:24 PST 2010. Objects in the Ephemeris -------------------------------------------------------- This file contains sample MSL (NAIF ID -76) EDL trajectory, from atmospheric entry interface point to landing, for Type 1B, open of launch period (11/25/2011), optimal launch time, central landing site (0.0 N, 45.0 E), landing time 06-AUG-2012 11:35:46.7 UTC. THIS FILE SHOULD BE USED FOR TESTING PURPOSES ONLY. Approximate Time Coverage -------------------------------------------------------- This file coverage is: COVERAGE BEGIN TIME (TDB) COVERAGE END TIME (TDB) ------------------------- ------------------------ 2012 AUG 06 11:30:58.537 2012 AUG 06 11:36:52.837 Pedigree -------------------------------------------------------- This file was provided by Fernando Abilleira, MSL MD/NAV on February 23, 2010. The original name of this file was 'day1_0.edlTraj.bsp'. Contacts -------------------------------------------------------- If you have any questions regarding this data contact Boris V. Semenov, NAIF/JPL, (818)-354-8136, Boris.Semenov@jpl.nasa.gov This particular kernel is just a list of positions and velocities at specific times, typically 0.1s apart. The attached CSV is a dump of the kernel at those times, plus some bonus stuff you can read about in the file. And here it is: msl_edl.txt ( 566.51K ) Number of downloads: 1129 (Why can't I upload a CSV? Rename this to msl_edl.csv when you get it) A couple of comments: 12 earth g's on entry! Phoenix peaked at 8. It flies for a long time, starting to gain altitude at about 110s and not opening the chute until 250s Of course I'll make an animation at some point, but I am actually more interested in this for analysis and backing out the aerodynamics model, so I can put it as a flyable model for Orbiter. |
|
|
||
Feb 17 2012, 03:20 PM
Post
#2
|
|
Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
Hey Kwan..
That animation was extremely sweet! Watching the landing ellipse come into view with a good enough model of Gale was exciting. I noticed that the the G forces topped out at 12.5+ during the burning reentry phase (lets hope MSL doesn't pass out!) I'm looking forward to your refinements. (what is the primary tool (or toolset) you are using?) Great job ! -------------------- CLA CLL
|
|
|
Feb 17 2012, 05:54 PM
Post
#3
|
|
Junior Member Group: Members Posts: 89 Joined: 27-August 05 From: Eccentric Mars orbit Member No.: 477 |
(what is the primary tool (or toolset) you are using?) Primary tool is PovRAY ray tracer. It takes a text file which describes the scene, where the spacecraft, planet, topography, sun, etc is. The scene description language is basically turing complete so that the scenes (at least how I do it) are more programs than anything. This is a mostly open-source program which I have been able to modify to directly read SPICE files. It is extremely high quality, but also extremely slow. It takes about 1 mintue to render each frame, and 24 frames per second of video. |
|
|
Feb 21 2012, 05:44 AM
Post
#4
|
|
Member Group: Members Posts: 404 Joined: 5-January 10 Member No.: 5161 |
Thanks, Kwan, for that animation. Very cool to see how it will happen in "real time."
|
|
|
Lo-Fi Version | Time is now: 26th April 2024 - 01:47 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE 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 funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |