Automotive navigation system

Navigation with Gosmore, an open source routing software, on a personal navigation assistant with free map data from OpenStreetMap.

An automotive navigation system is part of the automobile controls or a third party add-on used to find direction in an automobile. It typically uses a satellite navigation device to get its position data which is then correlated to a position on a road. When directions are needed routing can be calculated. On the fly traffic information can be used to adjust the route.

Dead reckoning using distance data from sensors attached to the drivetrain, a gyroscope and an accelerometer can be used for greater reliability, as GPS signal loss and/or multipath can occur due to urban canyons or tunnels.

History

Automotive navigation systems represent a convergence of a number of diverse technologies many of which have been available for many years, but were too costly or inaccessible. Limitations such as batteries, display, and processing power had to be overcome before the product became commercially viable.^[1] Etak made an early system that used map-matching to improve on dead reckoning instrumentation. Digital map information was stored on standard cassette tapes.^[2]

• 1966: General Motors Research (GMR) was working on a non-satellite-based navigation and assistance system called DAIR (Driver Aid, Information & Routing). After initial tests GM found that it wasn't a scalable or practical way to provide navigation assistance. Decades later, however, the concept would be reborn as OnStar.^[3]
• 1980: Electronic Auto Compass with new mechanism on the Toyota Crown.
• 1981: navigation computer on the Toyota Celica. (NAVICOM)^[4]
• 1987: Toyota introduced the World's first CD-ROM-based navigation system on the Toyota Crown.^[5]
• 1990: Mazda Eunos Cosmo became the first car with built-in GPS-navigation system^[6]
• 1991: Toyota introduced GPS car navigation on the Toyota Soarer.
• 1992: Voice assisted GPS navigation system on the Toyota Celsior.
• 1993: The Austrian channel ORF airs a presentation of the software company bitMAP and its head Werner Liebig's invention, an electronic city map including street names and house numbers, using a satellite-based navigation system. bitMAP attends Comtex in Las Vegas the same year, but doesn't manage to market itself properly.
• 1994: BMW 7 series E38 first European model featuring GPS sat nav. The navigation system was developed in cooperation with Philips (Philips CARIN).
• 1995: Oldsmobile introduced the first GPS navigation system available in a United States production car, called GuideStar.^[7]
• 1995: Device called "Mobile Assistant" or short, MASS, produced by Munich-based company ComRoad AG, won the title "Best Product in Mobile Computing" on CeBit by magazine Byte. It offered turn-by-turn navigation via wireless internet connection, with both GPS and speed sensor in the car.
• 1997: Navigation system using Differential GPS developed as a factory-installed option on the Toyota Prius^[8]
• 1998: First DVD-based navigation system introduced on the Toyota Progres
• 2000: The United States made a more accurate GPS signal available for civilian use.^[9]
• 2003: Toyota introduced the first Hard disk drive-based navigation system and the industry's first DVD-based navigation system with a built-in Electronic throttle control
• 2007: Toyota introduced Map on Demand, a technology for distributing map updates to car navigation systems, developed as the first of its kind in the world
• 2008: World's first navigation system-linked brake assist function and Navigation system linked to Adaptive Variable Suspension System (NAVI/AI-AVS) on Toyota Crown

Technology

The road database is a vector map. Street names or numbers and house numbers are encoded as geographic coordinates so that the user can find some desired destination by street address (see map database management).

Points of interest (waypoints) are stored with their geographic coordinates. Formats are almost uniformly proprietary; there is no industry standard for satellite navigation maps, although some companies are trying to address this with SDAL and NDS.

Map data vendors such as Tele Atlas and Navteq create the base map in a Geographic Data Files format, but each electronics manufacturer compiles it in an optimized, usually proprietary format. GDF is not a CD standard for car navigation systems. GDF is used and converted onto the CD-ROM in the internal format of the navigation system.

CARiN Database Format (CDF) is a proprietary navigation map format created by Philips Car Systems (this branch was sold to Mannesman VDO, which became VDO/Dayton in 1998, then Siemens VDO in 2002, then Continental in 2007) and is used in a number of navigation-equipped vehicles. The 'CARiN' portmanteau is derived from Car Information and Navigation.

SDAL is a proprietary map format published by Navteq, who released it royalty free in the hope that it would become an industry standard for digital navigation maps. Vendors who used this format include:

• Microsoft
• Magellan
• Pioneer
• Panasonic
• Clarion
• InfoGation

The format has not been very widely adopted by the industry.

Navigation Data Standard (NDS)

The Navigation Data Standard (NDS) initiative, is an industry grouping of car manufacturers, navigation system suppliers and map data suppliers whose objective is the standardization of the data format used in car navigation systems, as well as allow a map update capability. The NDS effort began in 2004 and became a registered association in 2009.^[10] Standardization would improve interoperability, specifically by allowing the same navigation maps to be used in navigation systems from 20 manufacturers.^[11] Companies involved include BMW, Volkswagen, Daimler, Renault, ADIT, Aisin AW, Alpine Electronics, Navigon, Navis-AMS, Bosch, DENSO, Mitsubishi, Harman International Industries, Panasonic, Preh Car Connect formerly TechniSat, PTV, Continental AG, Clarion, Navteq, Navinfo, TomTom and Zenrin.

Media

The road database may be stored in solid state read-only memory (ROM), optical media (CD or DVD), solid state flash memory, magnetic media (hard disk), or a combination. A common scheme is to have a base map permanently stored in ROM that can be augmented with detailed information for a region the user is interested in. A ROM is always programmed at the factory; the other media may be preprogrammed, downloaded from a CD or DVD via a computer or wireless connection (bluetooth, Wi-Fi), or directly used utilizing a card reader.

Some navigation device makers provide free map updates for their customers. These updates are often obtained from the vendor's website, which is accessed by connecting the navigation device to a PC.

Real-time data

Some systems can receive and display information on traffic congestion using either TMC, RDS, or by GPRS/3G data transmission via mobile phones.

Integration and other functions

• The color LCD screens on some automotive navigation systems can also be used to display television broadcasts or DVD movies.
• A few systems integrate (or communicate) with mobile phones for hands-free talking and SMS messaging (i.e., using Bluetooth or Wi-Fi).
• Automotive navigation systems can include personal information management for meetings, which can be combined with a traffic and public transport information system.

Original factory equipment

Many vehicle manufacturers offer a GPS navigation device as an option in their vehicles. Customers whose vehicles did not ship with GPS can therefore purchase and retrofit the original factory-supplied GPS unit. In some cases this can be a straightforward "plug-and-play" installation if the required wiring harness is already present in the vehicle. However, with some manufacturers, new wiring is required, making the installation more complex.

The primary benefit of this approach an integrated and factory-standard installation. Many original systems also contain a gyrocompass or accelerometer and may accept input from the vehicle's speed sensors, thereby allowing them to navigate via dead reckoning when a GPS signal is temporarily unavailable.^[12] However, the costs can be considerably higher than other options.

SMS

Establishing points of interest in real-time and transmitting them via GSM cellular telephone networks using the Short Message Service (SMS) is referred to as Gps2sms. Some vehicles and vessels are equipped with hardware that is able to automatically send an SMS text message when a particular event happens, such as theft, anchor drift or breakdown. The receiving party (e.g., a tow truck) can store the waypoint in a computer system, draw a map indicating the location, or see it in an automotive navigation system.

See also

• Augmented reality
• Automatic vehicle location
• Autonomous car
• GPS eXchange Format
• GPS navigation device
• Global Positioning System (GPS)
• Map database management
• Mapscape BV
• Mobile data terminal
• Navigation Data Standard (NDS)
• NavPix
• Navteq
• Personal navigation assistant (PNA)
• Traffic Message Channel (TMC)
• Hybride Navigation

References