. Mars Exploration News .




.
MARSDAILY
Rover Leaves Tracks in Morse Code
by Staff Writers
Pasadena CA (JPL) Aug 30, 2012

The straight lines in Curiosity's zigzag track marks are Morse code for JPL, which is short for NASA's Jet Propulsion Laboratory in Pasadena, Calif., where the rover was built and the mission is managed. The "footprint" is more than an homage to the rover's builders, however. It is an important reference mark that the rover can use to drive more precisely via a system called visual odometry. The Morse code, imprinted on all six wheels, is: .--- (J), .--. (P), and .-.. (L), as indicated in this image. Image credit: NASA/JPL-Caltech. For a larger version of this image please go here.

NASA's Curiosity rover took its first test stroll Wednesday Aug. 22, 2012, and beamed back pictures of its accomplishment in the form of track marks in the Martian soil. Careful inspection of the tracks reveals a unique, repeating pattern, which the rover can use as a visual reference to drive more accurately in barren terrain.

The pattern is Morse code for JPL, the abbreviation for NASA's Jet Propulsion Laboratory in Pasadena, Calif., where the rover was designed and built, and the mission is managed.

"The purpose of the pattern is to create features in the terrain that can be used to visually measure the precise distance between drives," said Matt Heverly, the lead rover driver for Curiosity at JPL.

This driving tool, called visual odometry, allows the rover to use images of landscape features to determine if it has traveled as far as predicted, or if its wheels have slipped. For example, when the rover drives on high slopes or across loose soil, it will routinely stop to check its progress.

By measuring its distance relative to dozens of prominent features like pebbles or shadows on rocks - or patterns in its tracks - the rover can check how much its wheels may have slipped.

If Curiosity has not slipped too much, it can then re-plan the next leg of its drive, taking its actual position into account.

"Visual odometry will enable Curiosity to drive more accurately even in high-slip terrains, aiding its science mission by reaching interesting targets in fewer sols, running slip checks to stop before getting too stuck, and enabling precise driving," said rover driver Mark Maimone, who led the development of the rover's autonomous driving software.

The Morse code imprinted on all six wheels will be particularly handy when the terrain is barren. Curiosity won't be able to read the Morse code symbols in the track marks directly, but it will note that the pattern is a high-contrast feature. This will give the rover the anchor it needs in an otherwise featureless terrain.

"Imagine standing in front of a picket fence, and then closing your eyes and shifting to the side. When you open your eyes, you wouldn't be able to tell how many pickets you passed. If you had one picket that was a different shape though, you could always use that picket as your reference," said Heverly.

"With Curiosity, it's a similar problem in featureless terrain like sand dunes. The hole pattern in the wheels gives us one 'big picket' to look at."

NASA's Mars Exploration rovers Spirit and Opportunity also used visual odometry to ensure accurate driving in difficult terrains. Their wheels had been bolted to their landing platform, leaving holes that left distinguishing marks in their tracks.

Those marks proved critical for the visual odometry system on Opportunity when it traversed the relatively featureless terrain at Meridian Planum. Opportunity is still trekking on Mars more than eight years after setting down on the Red Planet.

Curiosity likewise has holes in its wheels, only in the shape of Morse code letters.

"Even though Curiosity didn't need to be bolted down, we wanted to have the holes anyway. The mechanical team suggested multiple smaller holes rather than one large one like the Mars Exploration Rovers had, and one earlier design had spelled out letters in a cleat pattern, so I proposed using a Morse code version," said Maimone.

"And the rest is history."

Related Links
Mars Science Laboratory
Mars News and Information at MarsDaily.com
Lunar Dreams and more




.
.
Get Our Free Newsletters Via Email
...
Buy Advertising Editorial Enquiries






.

. Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle



MARSDAILY
NASA's Mars rover heads east, driving 'beautifully'
Los Angeles (AFP) Aug 29, 2012
NASA's Curiosity rover has begun its first major drive across the surface of Mars, handling "beautifully" as it prepares to start some serious scientific work, the US space agency said Wednesday. The $2.5 billion craft - which landed in Gale Crater on the Red Planet on August 6 - plans to drive a quarter-mile (400 meters) east, to a spot where it may use its drill for the first time, to bo ... read more


MARSDAILY
Russia's moonshot hope 'not a dream'

A "Blue Moon" Heralds the Harvest

Walls of Lunar Crater May Hold Patchy Ice, LRO Radar Finds

New research eclipses existing theories on moon formation

MARSDAILY
China's manned spacecraft in final preparations for mid-June launch

China eyes next lunar landing as US scales back

China unveils ambitious space projects

Is China Going to Blast Past America in Space?

MARSDAILY
Astronauts Complete Second Expedition 32 Spacewalk

Crew Makes Final Preps for Thursday's Spacewalk

Dragon Spacecraft Set to Make Second Run for ISS

Europe's ATV-3 Space Freighter Raises ISS Orbit to 420 km

MARSDAILY
The Kuiper Belt at 20: Paradigm Changes in Our Knowledge of the Solar System

e2v To Supply Large CMOS Imaging Sensors For Imaging Kuiper Belt Objects

Fly New Horizons through the Kuiper Belt

Hubble Discovers a Fifth Moon Orbiting Pluto

MARSDAILY
Saturn and its Largest Moon Reflect Their True Colors

Giant Ice Avalanches On Iapetus Provide Clue To Extreme Slippage Elsewhere In The Solar System

River networks on Titan point to a puzzling geologic history

Cassini Spots Daytime Lightning on Saturn

MARSDAILY
Proba-2's espresso-cup microcamera snaps Hurricane Isaac

$3.7 Billion Reasons Why GIS Technology is The Future

Landsat Data Continuity Mission Environmental Testing is Underway

Expert Analysis of Energy Infrastructure Using HiRes Satellite Imagery

MARSDAILY
XCOR Announces AdamWorks as Lynx Mark I Cockpit Manufacturer

Manned interplanetary missions on NASA's agenda

Space race, on a budget, was not how Armstrong saw it

Research and Technology Studies 2012

MARSDAILY
How Old are the First Planets?

NASA, Texas astronomers find first multi-planet system around a binary star

Planet search moves to Antarctica

Kepler discovers planetary system orbiting 2 suns


Memory Foam Mattress Review

Newsletters :: SpaceDaily Express :: SpaceWar Express :: TerraDaily Express :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

.

The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement