SAE TECHNICAL
`PAPER SERIES
`
`930455
`
`The Development of a New Multi-AV
`System Incorporating an On-Board
`Navigation Function
`
`Toru Hirata
`Nissan Motor Co., Ltd.
`
`Toshiaki Hara and Atul Kishore
`Nissan Research & Development, Inc.
`
`Reprinted from:
`Automotive Display Systems and IVHS
`(SP-964)
`
`The Engineering Society
`For Advancing Mobility
`Land Sea Air and Space
`I N T E R N A T I O N A L
`
` ®
`
`International Congress and Exposition
`Detroit, Michigan
`March 1-5, 1993
`
`400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel:(412)776-4841 Fax:(412)776-5760
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`ISSN 0148-7191
`Copyright 1993 Society of Automotive Engineers, Inc.
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`930455
`The Development of a New Multi-AV
`System Incorporating an On-Board
`Navigation Function
`Toru Hirata
`Nissan Motor Co., Ltd.
`
`ABSTRACT
`A new multi-AV system was developed
`for use in the 1991 Cedric,Gloria and Cima
`models. This system features the world's
`first production vehicle application of an
`optical fiber gyro, which dramatically improves
`position finding accuracy.
`New map-
`matching logic was also created and the map
`database was expanded so that the map-
`matching function can be used throughout
`Japan.
`Another first-ever feature in
`production vehicles is the compatibility with
`roadside beacons of the Vehicle Information
`and Communications System ( VICS )
`,enabling reception of Intersection information
`and automatic correction of vehicle position
`based on the data received.
`A touch screen
`h a s b e e n a d o p t e d f o r g r e a t e r e a s e o f
`operation,with screen switches newly provided
`for air-conditioner controls and a cellular car
`phone.
`This paper describes the
`configuration, functions and performance of
`the new multi-AV system.
`
`1. INTRODUCTION
`
`Although the number of vehicles on the
`road in Japan is continuing to increase every
`year, the construction of roads and highways
`is not keeping pace with the rise in vehicle
`ownership. This has given rise to a situation
`where traffic congestion is becoming worse
`with each passing year. Existing traffic control
`systems alone are unable to prevent this
`worsening of traffic congestion or the increase
`in traffic accidents, both of which are directly
`related to the rising number of vehicles on the
`road.
`
`1
`
`Toshiaki Hara and Atul Kishore
`Nissan Research & Development, Inc.
`
`In view of this situation, there is a
`recognized need to introduce new traffic
`control and management systems in Japan.
`The ideal form of such a system is thought to
`be one that would provide drivers with
`information on traffic congestion in real time,
`based on transmission of communications
`from road traffic information centers to
`individual vehicles via a network of roadside
`facilities. An onboard navigation system
`would then use that information to infer the
`shortest route to a particular destination and
`display it on a CRT in the passenger
`compartment for use by the driver. Work is
`now proceeding toward the implementation of
`such a system, which is called the Vehicle
`Information Communication System (VICS).
`Nissan Motor Company has for many
`years been engaged in R&D work on road and
`traffic information systems aimed at fostering
`their advancement and earliest possible
`implementation. This work is based on the
`recognition that such systems have tremendous
`utility and the potential to make significant
`contributions to society. In conjunction with
`the launching of a road and traffic system
`using a network of roadside electronic
`beacons, N i s s a n h a s d e v e l o p e d a n d
`commercialized a new Multi-AV System. This
`system, offered in the Cedric, Gloria and Cima
`models, is compatible with the network of
`roadside beacons and is intended to promote
`greater use of the system for communicating
`road and traffic information to drivers.
`This new Multi-AV System incorporates
`substantial improvements over previous
`versions of the system. It features the world's
`first production vehicle use of a fiber-optic
`gyroscope, which provides greatly improved
`position accuracy for navigation use. It also
`includes newly developed map-matching logic,
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`with a map database that covers the principal
`trunk roads throughout Japan. In addition,
`repeated evaluations were made of the man-
`machine interface during driving with the aim
`of improving ease of operation and safety.
`The results of these evaluations have been built
`into the system to achieve a high level of
`practicality.
`
`2. System Configuration
`
`The latest Cedric model is shown in
`Photo 1 and the appearance of the center
`console area is shown in Photo 2. Figure 1
`shows the configuration of the Multi-AV
`System and Fig. 2 gives a block diagram of the
`system.
`
`Fig. 1 Configuration of Multi-AV System
`
`Fig. 2 System Components
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`Fig. 3 Block Diagram of AV Control Unit
`
`Fig. 4 Block Diagram of NAVIGATION Control Unit
`
`An AV control unit installed in the trunk
`serves as the controller that manages the
`overall operating status of the system. As
`shown in Fig. 3, other main components
`making up the system include the TV and radio
`tuners, audio selector and the image processing
`unit.
`
`Connected to the main CPU are the
`navigation control unit, which serves as a
`subordinate CPU, cassette deck, compact disc
`player, panel control switches and other units.
`
`Optional equipment includes a digital signal
`processor (DSP), a car telephone control unit,
`a beacon signal receiver for road and traffic
`information and a GPS (Global Positioning
`System) signal receiver. The Multi-AV
`System automatically judges whether either of
`the latter two receivers is present.
`That
`judgment is activated by a connection
`c o m m a n d
`signal
`i n c l u d e d i n
`the
`communications format. The system then
`changes to the relevant screen display and
`operation menu.
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`The data link level of the communications
`protocol between the AV control unit (main
`CPU) and the subordinate units connected to it
`is compatible with JIS X5002, Basic Mode
`Data Transmission Control Procedures,
`specified by the Japanese Industrial Standards
`(JIS). Similarly, commands and parameters
`have been specified for each individual unit in
`the system.
`As indicated in Fig. 2, there are multiple
`subordinate units which are connected to a
`single master control unit. Because of this
`arrangement, one issue that had to be dealt
`with in designing the Multi-AV System was to
`assure a reliable fail-safe procedure in the event
`of a malfunction or component failure.
`Various measures were taken to minimize the
`possibility of misoperation due to momentary
`circuit breaks or short circuits, which are apt to
`occur in vehicles. Bench tests and in-vehicle
`tests of the system were conducted repeatedly
`in order to determine suitable data link levels
`and the physical interface. Self-diagnostic
`capabilities have been established which enable
`the system to pinpoint the location of a
`problem when a malfunction occurs in a unit.
`An error log display function is also provided
`to assist in identifying problems of a non-
`recurring nature.
`These measures have
`resulted in a high level of reliability and
`improved serviceability.
`
`3. Concept of Using Touch Control
`Switches for Improved Ease of
`Operation and Recognition
`
`A Drive Simulator was used to conduct
`tests of the ease of operation and safety of the
`In these tests,
`touch control switches.
`measurements were made of the time required
`by the subjects to recognize screen images and
`a record was kept of their results in performing
`specified tasks as explained below.
`The Drive Simulator used was a simple
`device which allowed a subject to simulate
`steering maneuvers and driving operations
`while watching a display screen positioned in
`front of the person. The following is a
`summary of the test results.
`(1) Touch switch color design -- background
`color and lettering color
`An example of the performance results
`obtained for various control switch color
`combinations is given in Fig. 5.
`
`Fig. 5 Relationship Between Control Switch Color Design
`and Performance Results
`
`Fig. 6 Screen Layouts of Control Switches
`
`Fig. 7 Recognition Time as a Function of Switch Number
`and Layout
`
`T h e r e s u l t s i n d i c a t e t h a t a c o l o r
`combination of a white background and black
`lettering provided the highest level of legibility.
`However, it was found in road tests that the
`h i g h a v e r a g e l u m i n a n c e o f t h e w h i t e
`background was annoying to the subjects
`during driving, especially at night when it was
`even more noticeable. As a result, the color
`combination of white lettering on a black
`background, which showed the second highest
`level of legibility in Fig. 5, was concluded to
`be suitable for the color design of the touch
`switches.
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`(2) Switch layout and number of switches
`An evaluation was made of the effect of
`the number of switches and switch layout (Fig.
`6) on recognition time (Fig. 7). The results
`indicated that recognition time was shorter for
`the switch layout denoted as "screen PA" than
`it was for the layout denoted as "screen PB."
`T h e f o r m e r l a y o u t h a d t h e s w i t c h e s
`concentrated near the center of the screen while
`the latter layout had the switches positioned
`around the periphery. It was also found that
`recognition time increased in proportion to the
`logarithm of the number of switches. It can be
`seen in Fig. 7 that one important factor is to
`keep the number of switches within a range
`that does not impose an excessive recognition
`burden on the driver.
`Based on these evaluation results, screen
`displays used in the Multi-AV System were
`d e s i g n e d i n
`l i n e w i t h t h e f o l l o w i n g
`considerations.
`1. Control switches common to different
`screen displays and those needed in an
`emergency have been positioned outside the
`screen as panel switches. These control
`switches include those for the air conditioner,
`air recirculation, defroster and audio system
`adjustment.
`2. Common color combinations, which
`are easy to see, have been adopted for the
`touch control switches of all screen displays.
`Care was taken to make it easy to distinguish
`between a control switch display (including
`preset function displays) and simple status
`displays (such as a radio station frequency
`display). The color combinations used are as
`follows:
`daytime:
`background
`nighttime: white lettering on a black
`background
`The color combinations are shown in Photos 3
`and 4.
`3. Based on their frequency of use,
`touch control switches have been divided into
`two categories, main and auxiliary. The
`former category includes the switches for
`presetting TV and radio channels, playback
`switches for the CD and cassette players and
`switches for selecting the vent discharge mode
`of the air conditioner. In addition, the main
`switches have been designed with a slightly
`larger size (20x20 mm).
`4. The evaluation results indicated that a
`recognition time of less than two seconds,
`
`black lettering on a gray
`
`including a certain extra allowance, was
`optimal during driving. The maximum number
`of switches in one display screen was set at
`eight, taking into account the relationship with
`the switch layout and switch number in Figs. 6
`and 7.
`The screen display for operating the car
`telephone while driving is shown in Photo 5.
`Up to eight telephone numbers can be
`registered in memory in advance and a call is
`placed by simply touching the desired memory
`key. Photo 6 shows the screen display for
`operating the telephone while the vehicle is
`stopped. In this case, telephone numbers are
`dialed as usual.
`5. The control switch layouts indicated
`as "screen PA" and "screen P3" in Fig. 6 have
`been adopted as standard.
`
`4. Overview of Navigation System
`
`4.1 Navigation control unit
`As indicated in Fig. 4, the navigation
`control unit primarily consists of a man-
`machine interface block, locator block, optical
`fiber gyroscope and CD player control block.
`(1) Man-machine interface block: This
`block handles the display of maps and the
`vehicle's present position, decipherment of
`control switch operations and communications
`with the beacon signal receiver. Maps can be
`shown in various scales including 1:400,000
`for road maps of Japan, 1:200,000 for the
`island of Hokkaido alone, 1:100,00 for road
`maps excluding Hokkaido, 1:25,000 for maps
`of cities having a population of 200,000 or
`greater and 1:12,500 for enlarged maps of
`certain areas. Typical map displays are shown
`in Photos 7~10.
`Switch operations make it possible to
`change the map scale, conduct a search for
`useful information (e.g., locations of golf
`courses, hotels
`and
`Japan Automobile
`Federation offices) and set the present position
`as well as the intended destination. Display
`and other operations are performed using CD
`CRAFT, an acronym for CD and CRt Applied
`Format. This CD software format is designed
`to run on automotive information display
`systems incorporating a CD-ROM. The reason
`for selecting CD CRAFT was to provide a
`format that would make it easy for software
`vendors to participate in the development of
`CD software products for use with automotive
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`systems. It is expected that this will lead to
`broader lineups of CD software products for
`these systems, thereby providing vehicle
`owners with greater satisfaction and promoting
`expansion of the navigation system market.
`The specifications of this software format have
`been determined jointly by Nissan and Toyota
`Motor Corporation.
`Communications signals received from
`the roadside beacons contain the names of
`approaching intersections and the destinations
`of roads leading from them. That information
`is shown on the CRT display for use by the
`driver. The location coordinates of a beacon
`are also fed into the locator block and that
`information is used in automatically correcting
`the position of the vehicle found by dead
`reckoning.
`(2) Locator block: This block supports
`more accurate selection of roads (i.e., map
`matching) based on position calculations
`performed by the CPU and an arithmetic
`processing unit. The calculations correlate
`different types of navigation information,
`including the vehicle heading estimated from
`the optical fiber gyroscope signal and
`geomagnetic sensor signal, the distance
`traveled as indicated by the vehicle speed
`sensor, and the internal map data stored in the
`CD -ROM.
`(3) Optical fiber gyroscope: The basic
`operating principle of the optical fiber
`gyroscope is to detect angular velocity based
`on the time difference between two optical
`signals, one of which propagates clockwise
`around a circular optical path and the other
`travels counterclockwise.
`
`Fig.8 Construction of optical-fiber gyroscope
`
`6
`
`The appearance of the gyroscope is
`shown in Photo 11 and its operating principle,
`known as the Sagnac effect, is illustrated in
`As outlined in the figure, light
`Fig. 8.
`emitted by a photodiode (a) passes through an
`optical fiber coupler (b) into a polarizer (e)
`where the input and output polarized waves are
`extracted in order to ensure the coherence of
`the optical path. The light is then separated
`into clockwise and counterclockwise signals
`by a second optical fiber coupler (c). Every
`revolution of the fiber coil of the sensing unit
`produces a light path difference and as a result
`the phase modulator at the end of the coil
`applies a bias of p/2
`to the light signals. The
`light signals are combined by coupler (c)
`again, pass through the polarizer into coupler
`(b) from which the light is sent through a
`separate fiber to a photodetector (d).
`The adoption of
`this optical fiber
`gyroscope makes it possible to trace the
`vehicle's path along
`the
`road network
`displayed on the screen more accurately than
`previous systems, which at times give the
`vehicle's position or heading
`inaccurately.
`Such
`inaccuracy can arise because
`the
`geomagnetic sensor is affected by vehicle
`magnetization, which can occur at railroad
`crossings. Heading error can also occur when
`a vehicle turns a gentle curve where the smaller
`difference
`in
`the number of revolutions
`between the two rear wheels makes it difficult
`to judge whether the vehicle is turning left or
`right, or when it turns in a circle having a
`small radius.
`4.2 Locator accuracy and algorithm concept
`At the time development of the Multi-AV
`System was getting under way, a comparison
`was being made at Nissan between two types
`of navigation systems. One was a stand-alone
`navigation system based on the use of an
`optical fiber gyroscope and the other was a
`satellite-based navigation system using the
`GPS satellites. Based on the results of that
`comparison, it was decided to configure the
`Multi-AV System as a stand-alone navigation
`system for the following reasons.
`1. The potential accuracy of the GPS-based
`navigation system was calculated on the basis
`of data released by the U.S. Department of
`Defense. It was found that, under conditions
`of space vehicle accuracy of 7 or less and
`dilution of precision of 3 or less, there was a
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`2-sigma probability that maximum error of ±
`203 m would occur in the worst case.
`2. In cities in Japan where the distance
`between adjacent roads and streets is quite
`small, error on the order of 200 m would
`likely result in mismatching between the
`calculated vehicle position and internal map
`data.
`3. Reception of satellite signals would be
`impaired by certain circumstances in Japan,
`such as in areas where relatively tall buildings
`are built closely together and in mountainous
`regions where there are numerous tunnels.
`4. It was decided that the system should be
`designed so that a GPS receiver or a beacon
`signal receiver could be attached as an
`additional function to compensate for large
`error in the vehicle's present position. Such
`error might occur as a result of matching
`inaccuracy, deviation between the vehicle
`location and internal map data or transportation
`of a vehicle on a car ferry.
`Taking these factors into account, the
`basic concept of the algorithm for the
`navigation system was formulated along the
`following lines.
`1. The vehicle position found from the internal
`map data by the locator block is corrected
`when it differs from the position indicated by
`the beacon signal data by 50 m or more. The
`location coordinate data transmitted by the
`beacons have a higher level of accuracy on the
`order of ±5 m. This correction procedure gives
`priority to the roadside beacons as the primary
`means of obtaining road and traffic information
`from the outside.
`2. The vehicle position found by the locator
`block is corrected using GPS signal data
`when certain conditions are satisfied. These
`include space vehicle accuracy of 7 or less,
`dilution of precision of 3 or less, the present
`location was not found by the micromatching
`mode of the stand-alone navigation method and
`it deviates from the GPS position by at least
`200 m. In addition, position corrections are
`also made under the first two GPS conditions
`when the vehicle's present position deviates
`from the GPS signal data by one kilometer or
`more.
`
`The position accuracy of the locator
`block has been improved in the latest version
`of the system by extending the map matching
`area to include all major roads throughout
`Japan. In the previous version of the system,
`the map matching area was limited to Japan's
`
`three largest cities of Tokyo, Osaka and
`Nagoya. A dual-mode matching logic was
`newly developed for the system. One is a
`micromatching mode, in which changes in the
`vehicle's orientation are detected within a small
`range of movement and that information is
`used to find the map data for map matching.
`The other mode is a macromatching mode, in
`which a map data search is made in a larger
`area based on the path of vehicle movement in
`5-kilometer intervals. The working principles
`of the two modes are shown in Fig. 9.
`
`Fig. 9 Map Matching Modes
`
`In the micromatching mode, a search is
`made for the map data within a small area. If a
`mismatch occurs between
`the vehicle's
`position and the map data when the vehicle
`turns a corner, the calculated vehicle position is
`matched to the internal map data. The area
`searched in the map data is within a distance of
`approximately 250 m from
`the vehicle's
`present position. In the macromatching mode,
`a search is made for the map data over a wider
`area. The system looks for a road shape that
`resembles the pattern of vehicle movement
`based on the vehicle's position and heading for
`every certain interval of travel. The area
`searched in the map data is within a distance of
`approximately one kilometer from the vehicle's
`present position.
`
`5. Road and Traffic Information
`Beacon System
`
`The Vehicle Information Communication
`System (VICS) is being promoted by the
`National Policy Agency, Ministry of Posts and
`T e l e c o m m u n i c a t i o n s a n d M i n i s t r y o f
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`Beacon transmitters are installed at a
`height of approximately five to ten meters from
`the road. Radio signals can be received within
`an area of 35 m before and after a beacon
`installation and for a distance of 15 m across
`the road. The vehicle-mounted receiver picks
`up the signals as the vehicle passes a beacon
`installation. The information that can be
`transmitted can be broadly divided into static
`and dynamic categories.
`(1) static information (service started in 1991)
`•
`present position information (location and
`name of place)
`•
`intersection
`intersection, etc.)
`useful information (names of destinations
`•
`of roads leading from an intersection, road
`names, etc.)
`
`(shape
`
`of
`
`information
`
`Construction in an effort to coordinate the
`individual work done by these government
`bodies to date on the development of road and
`traffic information systems. Previously, the
`C o n s t r u c t i o n M i n i s t r y s p o n s o r e d t h e
`d e v e l o p m e n t o f t h e R o a d - A u t o m o b i l e
`Communication System (RACS) while the
`Police Agency was working toward the
`development of the Advanced Mobile Traffic
`Information and Communication System
`(AMTICS). The aim of the VICS project is to
`advance the information and communications
`capabilities of motor vehicles and other forms
`of transportation. Three means of providing
`information to drivers are now being examined
`-- a network of roadside electronic beacons,
`FM multiplex broadcasting and a system of
`teleterminals. Among these three candidates, a
`system using a network of roadside electronic
`beacons was put into practical use in 1991.
`VICS is a digital communications system
`that makes use of roadside beacons to transmit
`various types of information to drivers,
`including position data and traffic information,
`via radio waves in the quasi-microwave band.
`Data signals are modulated by a Gaussian
`filtered minimum shift keying technique on a
`2.4997 GHz carrier and transmitted at a speed
`of 64 kbps with output power of 10mW. An
`outline of the system of roadside beacons is
`shown in Fig. 10. The specifications of the
`beacon signal receiver installed on vehicles are
`given in Table 1.
`
`Table. 1
`
`Specifications of Beacon Signal
`Receiver
`Radio Receiver Specifications
`Semi-microwave (2.4997GHz)
`1 Frequency
`GMSK
`2 Modulation method
`64 kbps
`3 Data transmission speed
`(BER<10-5)
`
`- 65 ~- 35dBm
`4 Reception level
`=
`5 Location detection accuracy ±5m (over 95 %)
`
`Fig. 10 System of Roadside Beacons
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`(2) dynamic information
`•
`information on traffic congestion ,
`warnings (accidents, disabled cars, etc.)
`•
`information on travel time, parking
`availability, etc.
`•
`simple image information, service area
`information of a changing nature, etc.
`5.1 Vehicle-mounted beacon signal receiver
`In addition to the GMSK-modulated data
`signal, a 1-KHz AM reverse phase modulated
`signal is superimposed on the beacon signals
`for use in accurate detection of the vehicle’s
`position immediately under a beacon antenna.
`With this modulation technique, the data signal
`emitted from the beacon antenna is divided into
`two portions. The AM modulated signal is
`modulated so that its rise phase differs directly
`below the antenna. The two portions of the
`signal propagate to the right and left along the
`road. As a result, a same phase zone and a
`reverse phase zone are formed with the beacon
`antenna in the center between them, as shown
`in Fig. 11.
`By using this phase relationship, the
`position of the vehicle directly under the
`beacon is detected (for use in correcting the
`present position) and the direction of vehicle
`travel is identified. The beacon signal receiver
`forwards that information to the navigation
`unit. With the Multi-AV System, a data parity
`check is performed when the electric field level
`of the beacon transmitter exceeds a certain
`threshold level.
`
`Provided the data are found to be normal,
`they are transmitted to the beacon signal
`receiver memory for storage and are then
`forwarded to the navigation control unit.
`Upon receipt of data, the navigation control
`unit generates an audible alert (beep) for the
`driver and displays the name of an approaching
`intersection, as shown in Photo 12.
`If no command is input by the driver, the
`intersection display automatically changes back
`t o t h e p r e v i o u s
`r o a d m a p d i s p l a y
`approximately 300 m beyond the intersection.
`By pressing the Destination Information key
`indicated in the screen display in Photo 12, the
`driver can change the screen display to that
`shown in Photo 13 to obtain information on
`the destinations of roads leading from the
`intersection. The latter screen display also
`changes back automatically to the previous
`road map display after the vehicle has traveled
`approximately 300 m from the intersection.
`
`6. Future Potential of Multi-AV
`S y s t e m
`
`T h e d e v e l o p m e n t o f t h e v a r i o u s
`technologies described in the foregoing
`sections made it possible to achieve a high
`l e v e l o f p r a c t i c a l i t y a n d a d r a m a t i c
`improvement in position accuracy in the latest
`version of the Multi-AV System.
`
`Fig. 11 Detection of Vehicle’s Position and Direction of Travel
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`At present, the number of beacon
`installations is small and the service areas are
`also limited in size. Yet, by expanding the
`number of beacon installations in the future
`a n d a d d i n g v a r i o u s t y p e s o f d y n a m i c
`information, such as data on traffic congestion,
`the utility of the system will be greatly
`enhanced at a single stroke. It is expected that
`the resulting benefits to society will be quite
`significant in terms of easing traffic congestion
`and shortening travel times.
`Future work should be directed toward
`expanding the VICS framework to include
`other communications media such as FM
`multiplex broadcasting and teleterminals. It is
`felt that car manufacturers should collaborate in
`this effort by developing onboard navigation
`systems capable of receiving information on
`traffic congestion and traffic restrictions from
`centers providing such information through
`roadside communications facilities. That
`information could then be processed and used
`
`to guide drivers to their destination in the
`shortest time possible.
`Acknowledgments
`The authors would like to thank the many
`people at the seven principal manufacturers
`who cooperated in the development and
`commercialization of the Multi-AV System.
`References
`(1) Y. Nishiura, et al., "Compact Optical Fiber
`Gyroscope," SANE 87-48, The Institute of
`Electronics, Information and Communication
`Engineers, (in Japanese).
`(2) K. Kimura, Y. Ohsumi and Y. Nagai,
`"Investigation of the Legibility of Automotive
`CRT Displays," JSAE, Vol. 43, No. 43, No.
`10, (1989), p. 70.
`(3) G. Labiale, "Influence of in Car Navigation
`Map Displays on Drivers Performances," SAE
`891683, (1989), p. 11.
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`p h o t o 1
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`p h o t o 6
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`p h o t o 2
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`p h o t o 3
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`p h o t o 7
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`p h o t o 8
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`photo 4
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`photo 9
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`photo 5
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`photo 10
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`photo 11
`p h o t o 1 1
`The appearance of
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`the gyroscope
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`photo 12
`p h o t o 1 2
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`027511?“ Xian
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`tntcrscction name: Airport Exit
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`Information §Wlllll
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`Pressing the Destination Information switch
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`changes the screen display to Photo 14
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`photo 13
`p h o t o 1 3
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`lmcrszutmn Name; Atrport Exit
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`L
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`Airport 2x1!
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