Editing Laser guidance

{{Short description|Method of guiding a projectile to a target}}
[[File:Guidance of multiple mobile robots by laser pointer.png|thumb|Mobile robot guidance by laser beam (sketch)]]

'''Laser guidance''' directs a robotics system to a target position by means of a [[laser]] beam. The laser guidance of a [[robot]] is accomplished by projecting a laser light, image processing and communication to improve the accuracy of guidance. The key idea is to show goal positions to the robot by laser light projection instead of communicating them numerically. This intuitive interface simplifies directing the robot while the visual [[feedback]] improves the positioning accuracy and allows for implicit localization. The guidance system may serve also as a mediator for cooperative multiple robots.<ref name=Paromtchik2006>
{{cite journal
|last1=Paromtchik |first1=Igor
|title= Optical Guidance Method for Robots Capable of Vision and Communication
|journal=Robotics and Autonomous Systems
|publisher=Elsevier
|year=2006
|volume=54|issue=6|pages=461–471
|url=https://app.box.com/s/h7mt5efgolt7isfghu71
|format=PDF
|doi=10.1016/j.robot.2006.02.005|url-access=subscription
}} 
</ref><ref name=Paromtchik2003>
{{cite journal
|title=Method and System of Optical Guidance of Mobile Body
|journal=U.S. Patent 6,629,028
|url=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=Paromtchik.INNM.&OS=IN/Paromtchik&RS=IN/Paromtchik 
}}
</ref>
Examples of proof-of-concept experiments of directing a robot by a [[laser pointer]] are shown on video.<ref name=Paromtchik2002> 
{{cite web 
|title=Mobile Robot Guidance by Laser Pointer
| website=[[YouTube]] |url=https://www.youtube.com/watch?v=2PgL6Npkmeg
 |archive-url=https://ghostarchive.org/varchive/youtube/20211212/2PgL6Npkmeg| archive-date=2021-12-12 |url-status=live|format=Video
|access-date=3 May 2015}}{{cbignore}} 
</ref><ref name=frostydesign2014>
{{cite web 
|title=Legged Robot Direction by Laser Pointer
| website=[[YouTube]] |url=https://www.youtube.com/watch?v=z-aXcIMYt5Q
 |archive-url=https://ghostarchive.org/varchive/youtube/20211212/z-aXcIMYt5Q| archive-date=2021-12-12 |url-status=live|format=Video
|access-date=3 May 2015}}{{cbignore}} 
</ref>
Laser guidance spans areas of robotics, [[computer vision]], user interface, video games, communication and smart home technologies.

== Commercial systems ==

[[Samsung|Samsung Electronics Co., Ltd.]] may have been using this technology in robotic vacuum cleaners since 2014.<ref name=gadgetify2014>
{{cite web 
|title=Samsung's Robotic Vacuum Cleaner Chases Laser Pointer
|url=http://www.gadgetify.com/samsungs-robotic-vacuum-cleaner
|date=7 August 2014
|access-date=3 May 2015}} 
</ref>  

[[Google|Google Inc.]] applied for a patent with USPTO on using visual light or laser beam between devices to represent connections and interactions between them (Appl. No. 13/659,493, Pub. No. 2014/0363168).<ref name=patentlymobile2014>
{{cite web 
|last1=Purcher |first1=Jack
|title=Google Invents a Smartphone that Could Transfer Data to a Large Smart Wall or Display using a built-in Laser Beam
|url=http://www.patentlymobile.com/2014/12/google-invents-a-smartphone-that-could-transfer-data-to-a-large-smart-wall-or-display-using-a-built-in-laser-beam.html
|date=14 December 2014
|access-date=3 May 2015}} 
</ref>
However, no patent was granted to Google on this application. 

== Military use ==
{{main|Precision-guided munition#Laser-guided|Beam riding}}
Laser guidance is used by [[military]] to guide a [[missile]] or other projectile or vehicle to a target by means of a laser beam, either [[beam riding]] guidance or semi-active laser homing (SALH).<ref name=Glaros2012>
{{cite journal
|title=Spot Leading Target Laser Guidance for Engaging Moving Targets
|journal=U.S. Patent 8,237,095
|url=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=8237095.PN.&OS=PN/8237095&RS=PN/8237095 
}}</ref> With this technique, a laser is kept pointed at the target and the laser radiation bounces off the target and is scattered in all directions (this is known as "painting the target", or "laser painting"). The missile, bomb, etc. is launched or dropped somewhere near the target. When it is close enough for some of the reflected laser energy from the target to reach it, a laser seeker detects which direction this energy is coming from and adjusts the projectile trajectory towards the source. While the projectile is in the general area and the laser is kept aimed at the target, the projectile should be guided accurately to the target. [[Countermeasure]]s to laser guidance are [[Laser warning receiver|laser detection systems]], [[smoke screen]], and anti-laser active protection systems.

== See also==
* [[Guidance system]]
* [[Laser rangefinder]]
* [[List of laser articles]]
* [[List of laser applications]]
* [[Semi-active radar homing]]

== References ==
{{reflist|2}}

{{DEFAULTSORT:Laser Guidance}}

{{Robotics}}
[[Category:Robot navigation]]
[[Category:Missile guidance]]
[[Category:Laser applications]]