Autonomous Vehicles - Adam Speirs

What are they?
Autonomous vehicles are vehicles that can drive itself from one point to another without the assistance of a driver within the vehicle itself. Therefore, in layman’s terms, an autonomous vehicle is one which is controlled via remote operation or pre-programmed instruction.
For example:

AUV's (autonomous underwater vehicles)
An autonomous underwater vehicle (AUV) is a machine which operates underwater. In military applications, AUV's are also known as unmanned undersea vehicles (UUVs). AUV's are controlled and powered from the surface by an operator/pilot via an umbilical.

Here is an image showing the Bluefin-12 AUV with a Buried Object Scanning Sonar (BOSS) integrated in two wings. This picture was taken in January 2005 of the coast of Florida during engineering trials.

AUV's have many comertial applications including extensive sea floor mapping, cheeper than usual surveying equipment, cause minimum disruption to the environment.

AUV's also have many military applications. A typical military mission for an AUV is to map an area to determine if there are any mines, or to monitor a protected area (such as a harbor) for new unidentified objects. AUVs are also employed in anti-submarine warfare, to aid in the detection of manned submarines.

Here is an image showing the military's "Blackghost" AUV. The Blackghost AUV is designed to undertake an underwater assault course autonomously with no outside control.

Sensors and Navigation:

Primarily oceanographic tools, AUVs carry sensors to navigate autonomously and map features of the ocean. Typical sensors include compasses, depth sensors, sidescan and other sonars, magnetometers, thermistors and conductivity probes. A demonstration at Monterey Bay in California in September 2006 showed that a 21-inch (530 mm) diameter AUV can tow a 300 feet (91 m) long hydrophone array while maintaining a 3-knot (5.6 km/h) cruising speed.

AUVs can navigate using an underwater acoustic positioning system. When operating within a net of sea floor deployed baseline transponders; this is known as (LBL) navigation. When a surface reference such as a support ship is available, ultra-short baseline (USBL) or short-baseline (SBL) positioning is used to calculate where the subsea vehicle is relative to the known (GPS) position of the surface craft by means of acoustic range and bearing measurements. When it is operating completely autonomously, the AUV will surface and take its own GPS fix. Between position fixes and for precise maneuvering, an inertial navigation system onboard the AUV measures the acceleration of the vehicle and Doppler velocity technology is used to measure rate of travel. A pressure sensor measures the vertical position. These observations are filtered to determine a final navigation solution. An emerging alternative is using an inertial navigation system in conjunction with either a GPS receiver, or an additional magnetic compass for Dead Reckoning whenever the GPS signal is lost.

References:

http://www.imtp.febras.ru/anpa/anpa_.html

http://oceanexplorer.noaa.gov/explorations/08auvfest/welcome.html

http://www.transit-port.net/Lists/AUVs.html

http://www.roperresources.com/