Editing Smart bullet

{{Short description|Guided bullet}}
A '''smart bullet''' is a [[bullet]] that is able to do something other than simply follow its given trajectory, such as turning, changing speed or sending data. Such a projectile may be fired from a [[precision-guided firearm]] capable of programming its behavior. It is a miniaturized type of [[precision-guided munition]].

==Types of smart bullets==
In 2008 the [[EXACTO]] program began under [[DARPA]] to develop a "fire and forget" smart sniper rifle system including a guided smart bullet and improved scope.  The exact technologies of this smart bullet have yet to be released.  EXACTO was test fired in 2014 and 2015 and results showing the bullet alter course to correct its path to its target were released.<ref>{{cite press release|url=https://www.darpa.mil/news-events/2015-04-27|work=DARPA|title=EXACTO Guided Bullet Demonstrates Repeatable Performance against Moving Targets|date=April 27, 2015|access-date=October 1, 2022}}</ref>

In 2012 [[Sandia National Laboratories]] announced a self-guided bullet prototype that could track a target illuminated with a [[laser designator]]. The bullet is capable of updating its position 30 times a second and hitting targets over a mile away.<ref>{{cite press release|url=https://share.sandia.gov/news/resources/news_releases/bullet|url-status=dead|archive-url=https://web.archive.org/web/20161220081042/https://share.sandia.gov/news/resources/news_releases/bullet/|work=Sandia National Laboratories|title=Sandia's self-guided bullet prototype can hit target a mile away|date=January 30, 2012|archive-date=December 20, 2016}}</ref>

In mid-2016, Russia revealed it was developing a similar "smart bullet" weapon designed to hit targets at a distance of up to {{convert|10|km|mi}}.<ref>{{cite news|url=https://www.military.com/kitup/2016/07/russians-launch-smart-bullet-effort-in-the-wake-of-u-s-program.html|website=[[Military.com]]|title=Russians Launch Smart Bullet Effort in the Wake of U.S. Program|date=July 20, 2016|access-date=October 1, 2022}}</ref><ref>{{cite news|url=https://tass.com/defense/889242|work=[[TASS]]|title=Russia launches 'smart bullet' testing in guided flight regime|date=July 19, 2016|access-date=October 1, 2022}}</ref>

== Guided bullet ==
The guided bullet was conceptualized by Dr. Rolin F. Barrett, Jr. and patented in August 1998.<ref>{{Cite web |title=US Patent for Guided bullet Patent (Patent # 5,788,178 issued August 4, 1998) - Justia Patents Search |url=https://patents.justia.com/patent/5788178 |access-date=2022-10-12 |website=patents.justia.com}}</ref>

As first designed, the bullet would have three [[fiber-optic]] based eyes (at minimum, for three-dimensionality), evenly distributed about its [[circumference]]. To activate its guided nature, a [[laser]] is pointed at a target. As the bullet approaches its final destination, it adjusts its flight path in real time to allow an equivalent amount of light from the laser to enter each eye. The bullet would not travel in multiple directions as though it were an [[autonomous vehicle]], but instead, would make small adjustments to its flight path to hit the target precisely where the laser was placed. Moreover, the laser would not have to originate from the source of the bullet, allowing the [[projectile]] to be fired at a target beyond visual range.<ref name=":0">“Feasibility Study of a Guided Bullet” (Louisiana Tech University Press 1996)</ref>

To allow the bullet to modify its flight path, the body was designed as a metal and [[polymer]] combination. The polymer would act as a deformable surface that would deflect the air-stream and steer the bullet in real time. The [[guidance system]] is powered by a miniature [[Lithium polymer battery|lithium-polymer battery]] that is connected to the navigational circuits.<ref name=":0" />

Barrett went to great lengths to model the airflow of the bullet, studying [[Butterfly|butterflies]] with speed bumps to evaluate the effects of protruding surfaces. Due to a lack of [[Ballistics|ballistic programs]] at the time, custom simulations were written in [[Mathcad]] to solve for numerous flight variables. In addition to modeling the flight, the [[interior ballistics]] were modeled by continuously altering [[polynomial curve]]s until they were in agreement with publicly available data. Due to a lack of available [[terminal ballistics]] data that would have been representative of the guided bullet, the data was compared to that of [[large game]] hunting bullets.<ref>Interview with Dr. Rolin F. Barrett, Jr (July 2020), Inventor on [https://patents.justia.com/patent/5788178 Guided bullet]</ref>

==Changing trajectory==
One kind of smart bullet is a projectile that is capable of changing its course during flight. One use of this would be to enable soldiers to stay behind protective cover and shoot around corners. One implementation uses a [[spoiler (aeronautics)|spoiler]] and micro [[gyroscope|gyro]] to control the bullet.<ref>{{cite web|url=https://www.freepatentsonline.com/6422507.html|work=Free Patents Online|title=Smart bullet {{!}} United States Patent 6422507|access-date=October 1, 2022}}</ref>

==Navigating==
[[Honeywell Aerospace]] has produced [[inertial measurement unit]]s based on [[Microelectromechanical systems|MEMS]] and microelectronics technologies that it claims can survive the shock of being fired out of a gun.<ref>{{cite web|url=http://www.honeywell.com/sites/portal?smap=aerospace&page=Missles_Munitions3&theme=T5&catID=C47E27B3A-58A6-A2E2-09FE-769AD775C886&id=H5AA6B1BD-95B2-AEA7-C62E-C28BC3E3EF73&sel=5&c=n|url-status=dead|archive-url=https://web.archive.org/web/20090708154627/http://www.honeywell.com/sites/portal?smap=aerospace&page=Missles_Munitions3&theme=T5&catID=C47E27B3A-58A6-A2E2-09FE-769AD775C886&id=H5AA6B1BD-95B2-AEA7-C62E-C28BC3E3EF73&sel=5&c=n|work=Honeywell Aerospace|title=Inertial Measurement Units|archive-date=July 8, 2009}}</ref>

==Transmitting data==
Another type of smart bullet is one that can transmit data about the location that has been hit. A prototype has been created by researchers at the [[University of Florida]] in [[Gainesville, Florida]], [[United States|USA]] with funding from [[Lockheed Martin]].<ref>{{cite news|url=https://www.newscientist.com/article/dn5054-smart-bullet-reports-back-wirelessly/|work=[[New Scientist]]|title='Smart bullet' reports back wirelessly|first=Will|
last=Knight|date=May 28, 2004|access-date=October 1, 2022}}</ref> The bullet (projectile) has the capability to send data up to a distance of 70 meters.

==References==
{{Reflist}}
[[Category:Ammunition]]
[[Category:Guided weapons]]
[[Category:Smart devices]]