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data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Charts_and_drafting_instruments" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Charts_and_drafting_instruments"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Charts and drafting instruments</span> </div> </a> <ul id="toc-Charts_and_drafting_instruments-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Direct_measuring" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Direct_measuring"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Direct measuring</span> </div> </a> <ul id="toc-Direct_measuring-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Position_finding_instruments" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Position_finding_instruments"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Position finding instruments</span> </div> </a> <button aria-controls="toc-Position_finding_instruments-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Position finding instruments subsection</span> </button> <ul id="toc-Position_finding_instruments-sublist" class="vector-toc-list"> <li id="toc-Celestial_navigation_instruments" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Celestial_navigation_instruments"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Celestial navigation instruments</span> </div> </a> <ul id="toc-Celestial_navigation_instruments-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bearing_instruments" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Bearing_instruments"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Bearing instruments</span> </div> </a> <ul id="toc-Bearing_instruments-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Compasses" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Compasses"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Compasses</span> </div> </a> <ul id="toc-Compasses-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Timekeeping" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Timekeeping"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.4</span> <span>Timekeeping</span> </div> </a> <ul id="toc-Timekeeping-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Electronic_Travel_Aid" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Electronic_Travel_Aid"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.5</span> <span>Electronic Travel Aid</span> </div> </a> <ul id="toc-Electronic_Travel_Aid-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a 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href="https://es.wikipedia.org/wiki/Instrumentos_de_navegaci%C3%B3n_n%C3%A1utica" title="Instrumentos de navegación náutica – Spanish" lang="es" hreflang="es" data-title="Instrumentos de navegación náutica" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Instrument_de_navigation" title="Instrument de navigation – French" lang="fr" hreflang="fr" data-title="Instrument de navigation" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Siglingat%C3%A6ki" title="Siglingatæki – Icelandic" lang="is" hreflang="is" data-title="Siglingatæki" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Navigatie-instrument" title="Navigatie-instrument – Dutch" lang="nl" hreflang="nl" data-title="Navigatie-instrument" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Instrument_de_naviga%C8%9Bie" title="Instrument de navigație – Romanian" lang="ro" hreflang="ro" data-title="Instrument de navigație" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Navigationsinstrument" title="Navigationsinstrument – Swedish" lang="sv" hreflang="sv" data-title="Navigationsinstrument" 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data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Tools used by navigators and pilots</div> <p><b>Navigational instruments</b> are <a href="/wiki/Measuring_instrument" class="mw-redirect" title="Measuring instrument">instruments</a> used by nautical <a href="/wiki/Navigator" title="Navigator">navigators</a> and <a href="/wiki/Pilot" class="mw-redirect" title="Pilot">pilots</a> as tools of their trade. The purpose of <a href="/wiki/Navigation" title="Navigation">navigation</a> is to <a href="/wiki/Geopositioning" title="Geopositioning">ascertain</a> the present <a href="/wiki/Location" title="Location">position</a> and to determine the <a href="/wiki/Velocity" title="Velocity">speed, direction</a>, etc. to arrive at the <a href="/wiki/Port" title="Port">port</a> or point of destination. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Charts_and_drafting_instruments">Charts and drafting instruments</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=1" title="Edit section: Charts and drafting instruments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Nautical_chart" title="Nautical chart">Charts</a></b> are maps of the areas to be navigated with details specific to the marine environment.</li> <li><b>Computing aids</b>: used in the necessary mathematical calculations. Today electronic <a href="/wiki/Computers" class="mw-redirect" title="Computers">computers</a> or <a href="/wiki/Calculators" class="mw-redirect" title="Calculators">calculators</a> are used. Other traditional aids used included tables (trigonometric, logarithms, etc.) and <a href="/wiki/Slide_rules" class="mw-redirect" title="Slide rules">slide rules</a>.</li> <li><b><a href="/wiki/Caliper#Divider_caliper" class="mw-redirect" title="Caliper">Dividers</a></b> used for measuring lengths of lines and approximate lengths of non-linear paths on a chart.</li> <li><b><a href="/wiki/Nautical_almanac" title="Nautical almanac">Nautical almanac</a></b> used to determine the position in the sky of a celestial body after a sight has been taken.</li> <li><b><a href="/wiki/Parallel_rulers" title="Parallel rulers">Parallel rules</a></b> used for transferring a line to a parallel position. Also used to compare the orientation of a line to a magnetic or geographic orientation on a <a href="/wiki/Compass_rose" title="Compass rose">compass rose</a>.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Direct_measuring">Direct measuring</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=2" title="Edit section: Direct measuring"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Chip_log" title="Chip log">Chip log</a> and <a href="/wiki/Hourglass" title="Hourglass">sand glass</a></b> serve to measure the ship's speed through the water.</li> <li><b><a href="/wiki/Sounding_line" class="mw-redirect" title="Sounding line">Sounding line</a></b> used to measure the depth of the water and to pick up samples from the bottom.</li> <li><b><a href="/wiki/Drift_meter" title="Drift meter">Drift meter</a></b> optically measures the effects of wind on an aircraft in flight.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Position_finding_instruments">Position finding instruments</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=3" title="Edit section: Position finding instruments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Celestial_navigation_instruments">Celestial navigation instruments</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=4" title="Edit section: Celestial navigation instruments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>These instruments are used primarily to measure the elevation or altitude of a <a href="/wiki/Celestial_object" class="mw-redirect" title="Celestial object">celestial object</a>: </p> <ul><li><b><a href="/wiki/Back_staff" class="mw-redirect" title="Back staff">Back staff</a></b>, the best known of which is the Davis' quadrant. It could measure the altitude of the Sun without having the navigator directly observe the Sun.</li> <li><b><a href="/wiki/Cross_staff" class="mw-redirect" title="Cross staff">Cross staff</a></b>, an older instrument long out of use.</li> <li><b><a href="/wiki/Kamal_(navigation)" title="Kamal (navigation)">Kamal</a></b> Very simple instrument used primarily by Arabian navigators. It consists of a small board with a knotted piece of twine through the center. The observer holds one of the knots in his mouth and extends the board away so that the edges make a constant angle with his eyes.</li> <li><b><a href="/wiki/Mariner%27s_astrolabe" title="Mariner's astrolabe">Mariner's astrolabe</a></b> Derived from the <a href="/wiki/Astrolabe" title="Astrolabe">astrolabe</a>, it was developed in late 15th century and found use in the 16th to 17th centuries. It was replaced by the <a href="/wiki/Back_staff" class="mw-redirect" title="Back staff">back staff</a> and later by the <a href="/wiki/Octant_(instrument)" title="Octant (instrument)">octant</a> and <a href="/wiki/Sextant" title="Sextant">sextant</a>.</li> <li><b><a href="/wiki/Quadrant_(instrument)" title="Quadrant (instrument)">Quadrant</a></b> A very simple instrument which used a plumb bob.</li></ul> <p>These instruments are also used to measure the angular distance between objects: </p> <ul><li><b><a href="/wiki/Octant_(instrument)" title="Octant (instrument)">Octant</a></b>, invented in 1731. The first widely accepted instrument that could measure an angle without being strongly affected by movement.</li> <li><b><a href="/wiki/Sextant" title="Sextant">Sextant</a></b>, derived from the octant in 1757, eventually made all previous instruments used for the same purpose obsolete.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Bearing_instruments">Bearing instruments</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=5" title="Edit section: Bearing instruments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Pelorus_(instrument)" title="Pelorus (instrument)">Pelorus</a></b> used to determine bearings relative to the ship's heading of landmarks, other ships, etc.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Compasses">Compasses</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=6" title="Edit section: Compasses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Bearing_compass" title="Bearing compass">Bearing compass</a></b> used to determine magnetic bearings of landmarks, other ships or celestial bodies.</li> <li><b><a href="/wiki/Magnetic_compass" class="mw-redirect" title="Magnetic compass">Magnetic compass</a></b> used to determine the magnetic heading of the ship.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Timekeeping">Timekeeping</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=7" title="Edit section: Timekeeping"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Marine_chronometer" title="Marine chronometer">Marine chronometer</a></b> used to determine time at the <a href="/wiki/Prime_meridian" title="Prime meridian">prime meridian</a> with great precision which is necessary when reducing sights in celestial navigation.</li> <li><b><a href="/wiki/Nocturnal_(instrument)" title="Nocturnal (instrument)">Nocturnal</a></b> used to determine apparent local time by viewing the <a href="/wiki/Polaris" title="Polaris">Polaris</a> and its surrounding stars.</li> <li><b><a href="/wiki/Sundial#Ring_dials" title="Sundial">Ring dial</a></b> or <b>astronomical ring</b> used to measure the height of a celestial body above the horizon. It could be used to find the altitude of the Sun or determine local time. It let sunlight shine through a small orifice on the rim of the instrument. The point of light striking the far side of the instrument gave the altitude or tell time.</li></ul> <p>All those mentioned were the traditional instruments used until well into the second half of the 20th century. After World War II electronic aids to navigation developed very rapidly and, to a great extent, replaced more traditional tools. Electronic speed and depth finders have totally replaced their older counterparts. <a href="/wiki/Radar" title="Radar">Radar</a> has become widespread even in small boats. Some Electronic aids to navigation like <a href="/wiki/LORAN" title="LORAN">LORAN</a> have already become obsolete themselves and have been replaced by <a href="/wiki/GPS" class="mw-redirect" title="GPS">GPS</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Electronic_Travel_Aid">Electronic Travel Aid</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=8" title="Edit section: Electronic Travel Aid"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As technologies are developed, designers and engineers have also turned their attention to minority groups like people that are visually impaired. In this case, Electronic Travel Aid are developed to target the needs of visual impaired individuals for obstacle identification as well as navigation of the surrounding to enhance mobility.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Not only GPS systems, there are other approaches like infrared sensors, ultrasonic sensors as well as optical technologies like cameras that are developed/ developing to enhance the navigation of the minority group.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=9" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Cras_plotter" class="mw-redirect" title="Cras plotter">Cras plotter</a></li> <li><a href="/wiki/Breton_plotter" title="Breton plotter">Breton plotter</a> (aka Portland plotter or Weems protractor)</li> <li><a href="/wiki/Navigation_protractor_triangle" class="mw-redirect" title="Navigation protractor triangle">Navigation protractor triangle</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=10" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">Li, Kun(LElectronic Travel Aids for Blind Guidanceinda). Sutardja Center for Entrepreneurship & Technology, Berkeley, California, 2015, pp. 1–10, Electronic Travel Aids for Blind Guidance.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text">Patra, Rusha, et al. “(PDF) an Electronic Travel Aid for Navigation of Visually Impaired Persons.” ResearchGate, Feb. 2011, <a rel="nofollow" class="external free" href="https://www.researchgate.net/publication/224219996_An_electronic_travel_aid_for_navigation_of_visually_impaired_persons">https://www.researchgate.net/publication/224219996_An_electronic_travel_aid_for_navigation_of_visually_impaired_persons</a>.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Navigational_instrument&action=edit&section=11" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://boatsafe.com/navigation/divide1.htm">How to use the dividers</a></li> <li><a rel="nofollow" class="external text" href="http://boatsafe.com/navigation/rules1.htm">How to use the parallel rulers</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20121211032356/http://www.marinersmuseum.org/collections/navigating-scientific-instruments">Navigational Instruments at The Mariners' Museum</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&useformat=desktop" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Navigational_instrument&oldid=1250117264">https://en.wikipedia.org/w/index.php?title=Navigational_instrument&oldid=1250117264</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Navigation" title="Category:Navigation">Navigation</a></li><li><a href="/wiki/Category:Navigational_equipment" title="Category:Navigational equipment">Navigational equipment</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 8 October 2024, at 15:27<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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