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Precision in agriculture reaches a new level with the Trimble AgGPS

214 high-accuracy receiver. Whether it is centimeter-level guidance along

crop rows, precise location of inputs, or high-accuracy field topographic

mapping, the AgGPS 214 makes all these tasks easy. High-precision jobs

are made easier, saving you time and money.

AgGPS 214 High-Accuracy ReceiverC E N T I M E T E R P R E C I S I O N I N A G R I C U LT U R E

A field prepared (listed) at night using the AgGPS 214 High-Accuracy Guidance System

2 TECH NOTES

Competitive agribusinesses today focus on improving their bottom line. Sub-meterDifferential GPS (DGPS) satisfies manyagricultural applications by improving application efficiency, saving time and/orreducing costs. But there are situations wherecentimeter-level precision is needed toachieve optimal performance and productivi-ty. For example, to ensure all field operationssuch as preparing seedbeds, planting, or cultivating are performed as efficiently aspossible. Field topographic mapping alsorequires centimeter precision. High-accuracyGPS equipment that is rugged and practicalto use is pivotal to achieving these tasks.Trimble has met this challenge by introduc-ing the state-of-the-art AgGPS 214 Real-Time Kinematic (RTK) receiver.

Trimbles highest accuracy AgGPS systemshave been designed with flexibility in mind.An AgGPS system can be customized for thetype of job you have. For centimeter-levelguidance, the AgGPS 214 receiver can beintegrated with the Parallel Swathing Optionto allow precise positioning along straightlines. Many agricultural operations can bene-fit from this exceptional precision for guidance, navigation, and mappingsuch asthe laying of irrigation tapes, workingaround drip irrigation, the preparation ofvery straight rows or seedbeds and the accurate placement of seed. In high-valuecrops even the application of fertilizer and

crop protection materials can benefit fromhigh-precision guidance. For topographicmapping and contouring, the AgGPS 214receiver is combined with the AgGPS 170Field Computer to log elevation data directlyonto Compact Flash data cards using theESRI (Environmental Systems ResearchInstitute) Shapefile format.

WHAT IS THE AgGPS 214?The AgGPS 214 is a GPS receiver designedspecifically for Real-Time Kinematic (RTK)operation in agricultural applications (see insetfor more information on RTK). The AgGPS 214hardware design is based on the proven ruggedhousing of the existing AgGPS receiver family.The front panel and menu layout are similar tothose of all other AgGPS receivers to ensure customer familiarity and ease of use.

The AgGPS 214 high-accuracy receiver can bepurchased alone or as part of a system designedfor precise guidance or topographic mapping.Both systems consist of an AgGPS 214 receiver,GPS dual-frequency antenna with 13-inchground plane, the TRIMCOMM 900M datalink radio, cables and manuals. For high-accura-cy guidance, the system includes the ParallelSwathing Option. For topographic mapping, thesystem includes the AgGPS 170 Field Computer.

TECH NOTES 3

WHAT IS RTK?Centimeter-level accuracy can be delivered by Trimbles Real Time Kinematic, or RTK solutions. Its a facet of GPS technology that extends the use of the GPS signals to get evengreater accuracy! The Trimble AgGPS 214 receiver is an RTK receiver designed and built for agricultural applications.

Trimble pioneered the commercial use of RTK in 1992, and since that time has seen it used on thousands of projects throughout the world. Thanks to RTK, these projects werecompleted more quickly, accurately and safely than was ever possible using conventionalmethods.

For an RTK system, you need to place a base station on a known, surveyed, point. In orderto obtain optimum accuracy, your mobile vehicle-based receivers must be within the rangeof 10 kilometers (6 miles) from your base station. The base station transmits corrections viaradio to any number of mobile receivers you have operating in the field. A typical radio linkrequired for RTK is in the UHF, VHF or spread spectrum radio band. Radios operate bestwithin line of sight or with a repeater.

A Trimble RTK base station receiver, for example the AgGPS 214, transmits data once persecond. Using radios like the TRIMCOMM 900M, the data is transmitted in a formatcalled CMR. CMR stands for Compact Measurement Record. Its a dual-frequency data for-mat invented by Trimble that transmits data in a more compact and robust way than otherformats. This makes data transmission to the roving receivers more reliable.

The GPS receivers used in Trimble RTK systems are dual-frequency receivers. Dual-frequen-cy receivers are a must if youre doing any sort of task requiring centimeter precision. As wellas picking up the standard code and carrier phase GPS signals like all other GPS receivers,Trimbles dual-frequency receivers track the second carrier phase signal. It is this signal thatenables the RTK receiver to lock into the higher accuracy. Since Trimble dual-frequencyreceivers pick up two carrier phase signals, you can initialize quickly. Initialization is theprocess a receiver goes through to get the information that it needs from the satellites togenerate high accuracy positions. One minute is typical for initializing to obtain centimeter-level accuracy. Trimbles RTK receivers output precise data at rates better than one secondrates of five to twenty times per second are not uncommon!

To date, Trimble RTK technology has been used for many projects worldwide spanning marine, survey, mining and construction applications. Agriculture can also benefitfrom the use of centimeter-level GPS for precision guidance or topographic mapping. Thebenefits include huge savings in time and money, plus greater accuracy.

MODULAR AgGPS FIELD MANAGEMENT SYSTEMSTrimble has a modular interoperable familyof products allowing you to create anAgGPS Field Management System to suityour needs. Select from the widest range ofAgGPS receivers as your foundation to theAgGPS Field Management System.

Start with adding an AgGPS ParallelSwathing Option for guidance, then youcan choose to add on an AgGPS 170 FieldComputer for a top-of-the-line precisionagriculture solution providing field map-ping, record-keeping and site-specific capabilities.

If high-precision work to within centi-meters is your focus, select the AgGPS 214as your receiver and then add on theAgGPS Parallel Swathing Option to pro-vide the most precise guidance system onthe market. Alternatively, include theAgGPS 170 Field Computer to performfield topographic mapping.

AgGPS ReceiversTrimble offers a number of AgGPSreceivers that have been specificallydesigned for the precision agriculture envi-ronment. You can choose a receiver thatbest meets your accuracy and budgetrequirements. Contact your nearest Trimblesales representative for more details aboutTrimbles AgGPS receivers.

AgGPS Parallel Swathing OptionThe AgGPS Parallel Swathing Optionlightbar provides clear and immediate guid-ance along swath lines. The lightbar has arow of bright lights (LEDs) that indicatethe vehicles distance offline, and an eight-

character text screen to display user-selectedinformation such as swath number andground speed. It is easily mounted on thedash or from the ceiling of any spray truck,spreader, or tractor cab. The lightbarsbright LEDs ensure clear guidance in day-light. A dimmer feature enables the intensi-ty to be reduced for night operations.

AgGPS 170 Field ComputerThe AgGPS 170 Field Computer is arugged field computer with daylight-readable color display designed for agricul-tures environmental extremes. By integrating the modular AgGPS 170Field Computer with an AgGPS receiver ofyour choice and the AgGPS ParallelSwathing Option, you form an AgGPSField Management System. Software modules run on the AgGPS 170 FieldComputer, designed for a range of preci-sion agricultural operations such as guid-ance, record-keeping, logging, variable rate,soil sampling and field mapping.

Benefits of the High-Accuracy AgGPS Field Management Systems The AgGPS 214 hardware is rugged,

ensuring reliability in harsh agricultural conditions.

Save time with the AgGPS 214s easy setup and configuration, using the same proven and popular AgGPS receiver front panel and menu user interface.

Applicable to a wide range of agricultural tasks requiring the greatest precision

4 TECH NOTES

Text display Approach LED Guidance LEDs

Lightbar Swivel MountConnector

(for example, bedding, listing, planting of seeds or trees, spraying, spreading, cul-tivating, variable rate treatments, etc).

Flexibility in your AgGPS Field Management Systemsswap out thesubmeter-level AgGPS receiver to use the high-performance AgGPS 214 for centimeter-level guidance and topo-graphic mapping services.

For Guidance- Save time and money throughout

listing, bedding, planting, and other field operations by ensuring consistently straight parallel rows.

- Avoid accumulated driver errors from one pass to the next.

- Reduce the need for experienced drivers. Even inexperienced operators do a great job with very little training.

- Eliminate guess rows.

- Extend your operating hours. Work at night, in fog or dusty conditions.

- Reduce operator fatigue and ensure you cover the field efficiently with the easy-to-follow lightbar.

- Minimize soil compaction using precise guidance along the same swaths for each field pass.

For Topographic Mapping- Save time with easy file transferall

data is recorded in Shapefile format on handy CompactFlash cards.

- Field data collection is automated, providing accurate records of the job done and assists with staff timesheet collection.

- Save time by setting up and collecting topographic data faster.

Available in AgGPS 170 Version 3 software.

TECH NOTES 5

MENU

NEXT ESC

_+

TENTER

+ _?

T

AgGPS ParallelSwathing Option

AgGPS 170 Field Computer

AgGPS 214 RTKreceiver and

TRIMCOMM 900Mradio

* Base Station receiver and radio not shown

AgGPS 214 FIELD MANAGEMENT SYSTEMS

6 TECH NOTES

HOW TO USE THE AgGPS 214 INAGRICULTURETrimbles AgGPS products are highly inter-operable. By combining the high-performanceRTK AgGPS 214 receiver with the AgGPSParallel Swathing Option, you create an AgGPSField Management System for centimeter-levelprecise guidance. Alternatively, by combiningthe AgGPS 214 with the AgGPS 170 FieldComputer, you create an AgGPS Field Manage-ment System for field topographic mapping.(See diagram on page 5.)

Equipment SetupBase Station and Radio Setup: Initially select a basestation location which has a clear, unobstructedview towards the field you will be working in.The AgGPS 214 base station should be within10 km or 6 miles of the area you are working.To ensure maximum range of the radio at thebase, keep the TRIMCOMM 900M elevated ashigh as practical.

If you require absolute accuracy in your fieldmapping, where the horizontal positions andelevations are tied to known, absolute referencepoints, you need to set up the base stationantenna over a known, surveyed location.However, if only relative accuracy is required,where your horizontal positions and elevationsin the field are computed at centimeter-levelprecision relative to the base position, then youcan set up the base station at any convenientlocation (maintaining, of course, the clear viewsto the sky and field of interest). Be sure, in thiscase, to keep a record of starting position (lati-tude, longitude, and height) of the base station,including the antenna height above any pointyou may mark on the ground. If possible,mount the base station permanently so that youcan perform all your high-accuracy operationswithout repositioning the base each time.

AgGPS 214 Setup: The AgGPS 214 has a front-panel, 2-line, 16-character LCD display showingall the status information of the GPS receiver,including: position, altitude, speed, heading,PDOP, HDOP, VDOP, satellites used, positionmode, differential RTK status, and status infor-mation of the received base station data. Thekeypad and the display can be used to configureall of the AgGPS 214 receiver settings and theinput/output (I/O) selections, including theNMEA messages and the Parallel SwathingOption settings. An office computer softwareprogram, Remote Controller, provides anotherway to configure the AgGPS 214.

The I/O ports on the AgGPS 214 may be configured for the lightbar, NMEA, DGPS corrections and CMR corrections (CMR istransmitted from the AgGPS 214 base receiver).Connector Port A has one pair of receive andtransmit lines. Connector Port B has two pairsof receive and transmit lines. In addition, eachconnector has an independent CAN bus port.

High-Precision Guidance Most chemical applicators require DifferentialGPS (DGPS) with sub-meter accuracy toimprove their application efficiency. Such taskscan be performed using the AgGPS ParallelSwathing Option combined with a sub-meterDGPS receiver of choice (e.g. AgGPS 124 orAgGPS 132). In situations such as growing high-value crops and managing very high-cost inputs,the demand for higher precision guidance goesup.

By incorporating the AgGPS 214 with theAgGPS Parallel Swathing Option, the accuracyof field guidance and product placement attainsa new level. Now you can achieve very preciseguidance along crop rows and pre-markedstraight lines.

At critical times of the year experienced opera-tors can be hard to find. At other times fieldwork must continue at all costs. The AgGPS 214with Parallel Swathing Option lets everyone,even the inexperienced operator, perform verystraight parallel lines for seedbed preparation,planting, precision application, and even har-vesting. Hours of operation can be extendedinto low visibility conditions such as at night, infog or dusty conditions. Field work gets done ontime and soil structural damage is reduced bycontrolling field traffic.

Specialty crops can require the formation of verystraight rows with raised seed beds, followed byaccurate placement of fertilizer into the seedbeds, and finally the crop is planted as close tothe fertilizer and center of the raised bed as possible. Guidance using the AgGPS 214 receiver can ensure the straightest rows and themost accurate positioning of material possiblefrom one pass to the next.

Some operations are costly to repeat each yearsuch as the laying of irrigation tapes or drips in afield. These tapes can be mapped as they are laiddown, so operators in subsequent field passesavoid damaging the existing tapes. To obtainguidance along pre-mapped lines or curves, fromone pass to the next (for example, irrigation tapelines), simply combine the AgGPS 170 FieldComputer with your AgGPS 214 and AgGPSParallel Swathing systems. This lets you recordswath patterns, crop rows or lines and save theseas Shapefiles on the data card. Reload thesemapped features into the AgGPS 170 FieldComputer for guidance in field operations nextyear or next season.

Setup and Equipment: The high-accuracy guidancesystem includes: AgGPS 214 receiver and dual-frequency

antenna with 13" ground plane TRIMCOMM 900M data link radio Cables and mounts

TECH NOTES 7T

ExternalKeypad

Base StationGPS Antenna

GPS Antenna

Rover Radio

Base Station Radio

Lightbar

AgGPS 214 Rover Receiver

FIELD SETUP FOR HIGH-ACCURACY GUIDANCE

Manual AgGPS Parallel Swathing Option (which

includes a lightbar, external keypad, cable, and manual)

You will also need an AgGPS 214 base stationand an additional TRIMCOMM 900M basestation radio.

Once the AgGPS 214 receiver, base station andradio link are set up, securely mount the AgGPSParallel Swathing lightbar, GPS and radio anten-nas on the agricultural vehicle being used forguidance. The radio and GPS antennas must bemounted on elevated points on the vehicle toensure reception of signals from the base andfrom GPS satellites in the sky. It is recommend-ed to mount the GPS antenna in a central location on the vehicle (for example, the centerof the cab roof).

Guidance: Centimeter-level guidance is easy withthe AgGPS 214 and the AgGPS ParallelSwathing Option. Simply set your swath widthto that of your equipment width, then drive toyour A and B points to define a straight A-Bline. Guidance relative to this line is then pro-vided across the rest of the field. Alternatively,drive the field boundary and get headland orend row guidance.

Throughout the field operation, the lightbarshows how far you are from the swath center-line. By centering the row of lights on the light-

bar, you will keep the vehicle on the swath centerline. A user-configurable text display provides key information such as swath numberand distance offline.

Topographic Mapping of Agricultural FieldsField topography is a major driver of crop yield,due to its effect on soil properties and drainage.For this reason, precise centimeter-level fieldtopographic maps are an essential site-specificlayer in a farmers precision agricultureGeographical Information System (GIS).Topographic maps can also be used for levelingor improved drainage.

Collecting elevation data for topographic mapsof agricultural fields has never been easier! Byintegrating the AgGPS 214 RTK receiver withthe AgGPS 170 Field Computer, you can collectcentimeter-level three-dimensional positioninformation (that is, horizontal position andheight data) into an ESRI Shapefile. The day-light-readable color display of the AgGPS 170Field Computer lets you map the field to be sur-veyed and record where you have already driven.The AgGPS Parallel Swathing Option lightbarcan also be used to provide guidance over thefield, so the operator can be sure to evenly coverthe extent of the field. Back in the office, thetopographic data can be processed with a num-ber of GIS mapping programs to create a three-dimensional topographic map of the field

8 TECH NOTES

Field listed at night using the AgGPS 214 High-Accuracy Guidance System

surface. Alternatively, a portable computer canbe configured to record the field topographicdata from the AgGPS 214.

Setup and Equipment: The AgGPS 214 topo-graphic mapping system equipment includes: AgGPS 214 RTK receiver and dual-frequency

antenna with 13" ground plane TRIMCOMM 900M data link radio Cables and mounts Manual AgGPS 170 Field Computer System (which

includes the computer, cable and junction box, CompactFlash data card with PC card adapter, shock resistant tilt and swivel pole mounting bracket, manual, and ESRI ArcExplorer GIS software on CD-ROM).

You will also need an AgGPS 214 base stationand an additional TRIMCOMM 900M basestation radio. You can choose to include light-bar-aided guidance throughout the topographicmapping process by purchasing the AgGPSParallel Swathing Option.

Once the AgGPS 214 base station receiver andradio link are set up, securely mount the AgGPS170 Field Computer, AgGPS Parallel Swathingsystem, AgGPS 214 rover receiver, GPS radioand antennas on the agricultural vehicle beingused to perform the mapping. The radio andGPS antennas must be mounted on elevatedpoints on the vehicle to ensure reception of signals from the base and from GPS satellites inthe sky. It is recommended to mount the GPSantenna in a central location on the vehicle (forexample, the center of the cab roof).

Real-Time Data Collection: Data collection involvessetting an appropriate vehicle swath width,driving the field and logging. Throughout theprocess the color AgGPS 170 Field Computerdisplays on-screen coverage logging on the mapdisplay or Plan View Map. This allows the operator to monitor how much of the field hasbeen completed or identify any gaps via the coverage logging. You can add the optional light-bar for guidance across the field to ensure youevenly cover the entire topographic area.

TECH NOTES 9

T

TAgGPS 170Field Computer

Base StationGPS Antenna

GPS Antenna

Rover Radio

Base Station Radio

AgGPS PSOLightbarAgGPS 214

Rover Receiver

FIELD SETUP FOR TOPOGRAPHIC MAPPING

Useful information is displayed on the AgGPS170 Field Computer including the quality of theRTK GPS position and number of elevationpoints recorded. All information is recordedonto the CompactFlash data card in the AgGPS170 Field Computer using the Shapefile format.

Data Analysis: When you have completed the col-lection of the elevation data, simply remove theCompactFlash data card from your AgGPS 170Field Computer and load it into your officecomputer. You can select from a wide range ofGIS software to read ESRI Shapefiles for con-touring or interpolation. Examples of suitablesoftware include: ESRIs ArcView with extensions Spatial Analyst

and 3D Analyst SST Development Groups SSToolbox or

SSToolbox Lite Agriss AgLink

The detailed logging Shapefile contains a pointfeature for each data point collected at a one- second interval. For each point, the followingattributes are collected in the dBase (.dbf) file: Software version number, date and local time GPS status Ground speed (km/h or mph) Logging status (on = 1 or off = 0) UTC (Universal Time Coordinated) Time

Antenna WGS84 latitude & longitude position

Antenna height (Height Above Ellipsoid, HAE) Ground height (HAE) Mean Sea Level (MSL) height Heading Left-hand boom size Right-hand boom size DOP (Dilution of Precision) as a measure of

GPS position quality Number of GPS satellites Swath number Correction age Units Offline distance Along line distanceUsing any dBase editor such as Microsoft Excel,you can easily edit the dBase file to retain onlythe columns you need. Note: It is recommended to use Mean Sea Level (MSL) height fortopographic maps.

SUMMARYThe AgGPS 214 RTK receiver presents newopportunities for those agricultural applicationsdemanding ruggedness and reliability of equip-ment while dealing with such high-precision.The Trimble AgGPS 214 seamlessly integratesinto your AgGPS Field Management System.For guidance you save time and money by beingable to form consistently straight and parallelcrop rows, ensuring subsequent field operations

10 TECH NOTES

AgGPS 170 Field Computers Plan View Map while collecting elevation data points

are more efficient. This also avoids damage tocostly irrigation tapes or drips. For topographicmapping you have an automated system that isvery easy to set up and use, providing elevationdata in the popular Shapefile format.

AgGPS 214 EQUIPMENT SPECIFICATIONSStandard Features Centimeter accuracy Real-Time Kinematic processing Receives 9 L1 channels and 9 L2 channels External CMR or RTCM correction input RTK Fixed, RTK Float, and DGPS modes Three programmable RS-232 serial ports Positioning based on dual-frequency carrier

phase processing 1 PPS output Configuration via front panel and keypad 5 meter antenna cable Dual-frequency antenna with 13-inch ground

plane and integral magnetic mount

Options AgGPS Parallel Swathing Option AgGPS 170 Field Computer

Physical CharacteristicsSize 14.5cm W x 5.1cm H x 23.9cm D

(5.7" W x 2.0" H x 9.4" D)Weight 1.0kg (2.25 lbs)Power 12 VDC/24 VDC, 9 WattsOperating Temp 20 C to +60 C

(4 F to +140F)Storage Temp 30 C to +80 C

(22 F to +176 F)Humidity MIL 810 E, Meth. 507.3

Proc III, Aggravated, 100% condensing

Vibration MIL 810 D, TailoredRandom 3gRMS (Operating)Random 6.2gRMS (Survival)

Mechanical Shock MIL 810 D+40g Operating+75g Survival

Performance Characteristics GPS ReceiverGeneral Dual 12-channel, dual-frequency

Carrier phase receiverUpdate Rate 10 Hz Standard; 20 Hz Optional

with MS750 upgrade packageCarrier Phase Position Accuracy

1 cm + 1 ppm baseline distanceTime to First Fix

12 TECH NOTES

Copyright 2000, Trimble Navigation Limited. All rights reser ved. The Trimble logo with Trimble and AgGPS are trademarks of Trimble Navigation Limited registered in the United States Patent andTrademark Office. TRIMCOMM is a trademark of Trimble Navigation Limited. All other marks are the property of their respective owners. TID11843A (03/00)

TRIMBLE AUTHORIZED DEALER

Trimble Navigation LimitedCorporate Headquarters645 North Mary AvenuePost Office Box 3642Sunnyvale, CA 94086http://www.trimble.comemail: precision_ag@trimble.com

Precision Agricultural Systems9290 Bond Street, Suite 102Overland Park, Kansas 66214Phone: 1-800-865-7438Phone: 1-913-495-2700AustraliaPhone: +61-7-3216-0044EuropePhone: +44-1256-761-130