GPS GYRO COMPASS SYSTEM OWNER'S MANUAL PART NUMBER: GGC-E101 GPS Module and Dual Antenna System WATSON INDUSTRIES, INC. 3035 MELBY STREET EAU CLAIRE, WI 54703 Phone: (715) 839-0628 FAX: (715) 839-8248 email: support@watson-gyro.com Watson Industries, Inc.
TABLE OF CONTENTS 1. Introduction ........................................................................................................ 3 2. Product Description............................................................................................ 3 3. Installation .......................................................................................................... 3 Environment .....................................................................................................................
CAUTION! Watson Sensors are rugged devices that have been used successfully in a number of harsh environments. The components have been qualified to withstand a mechanical shock of 200g 's or greater, and most enclosures provide an added level of protection. However, dropping a sensor from waist height onto a hard floor can cause a shock level of 600g's. At this level, damage is likely to occur.
Orientation The GGC unit side that has carrying handle needs to be aligned along the heading direction. See Figure 1. Heading Direction Figure 1 – Alignment Handle Mounting The GGC-E101 case needs to be placed on a flat horizontal surface. Unsnapping the four plastic clasps opens the GGC case. The case cover needs to be fully opened so that the cover is below the antennas when they are deployed to avoid interference with the GPS satellite signals.
Wire straps Metal clasp Antenna arm Antenna assembly straps Figure 2 – GGC-E101 Stowed Deployment After the unit is aligned and connections have been completed, the antennas can be deployed. See Figure 3 for information on deploying the antennas. First open the two straps that secure the antenna assembly. Now pivot the assembly up and toward the side of the case. Be careful not to pinch your fingers between the antenna assembly and case side.
unobstructed view of the entire sky to receive signals from GPS satellites. The GGC is now ready to operate. See the Operation Section on page 8. Step 1 – Open Case Step 2 – Raise Antenna Assembly Step 3 – Extend antenna arms and secure metal clasps Figure 3 – Deployment Stowing When finished taking measurements with the GGC it is time to repack the unit. First shutoff the DC power supply to the unit and remove Red and black wires from power supply. Next disconnect Watson Industries, Inc.
the RS-232 serial connection to the computer. See Figure 4 for information for help in stowing the antenna assembly and cable. Now unclasp the right-hand antenna and swing the antenna arm clockwise to the stowed position. Next unclasp the left-hand antenna and swing the antenna arm clockwise to the stowed position. Make sure the two straps that secure the antenna assembly are open and out of the way. Pivot the antenna assembly down and into the bottom of the case.
Operation Power Up The GGC unit output messages can be read by using a terminal program. Now it is time to power up the data collection computer and start the terminal program for the serial port connected to the GGC. Next the power needs to be switched on for the GGC unit. Figure 5 – GGC-E101 Deployed Initialization Ideally, the GGC should be stationary and level when it is turned on. If not, the sensor readings may not be immediately accurate after initialization.
Example of the GGS header: GGC-E101 INITIALIZING SERIAL NUMBER - 0177 LAST CALIBRATED - 10/12/10 SOFTWARE VERSION - GG01_00A 2010-12-13 COPYRIGHT (C) 1990 THROUGH 2010 WATSON INDUSTRIES, INC. Normal Operation During normal operation, the GGC will output highly accurate inertial data for the user to interpret. This data is transmitted using the RS-232 serial output. The unit also relays GPS messages. The exact formatting structure is discussed later in the Interface section of this manual.
$GPHDT Message Format The $GPHDT consists of a string ASCII characters sent asynchronously at regular intervals. The string is sent at 9600 baud with eight data bits, one stop bit and no parity. The contents of this string are formed as follows: $GPHDT,xxx.xx,T*cc 1. The ”$GPHDT” header indicates the start of the data string. . This data is followed by a comma. 2. “xxx.xx” is a variable character string (minimum-4, maximum-6) representing the gyro stabilized true North heading 0.00 to 359.
5. “dddmm.mmmmm” is an eleven character string representing the Longitude in “ddd” degrees, “mm” minutes, and “.mmmmm” decimal fraction minutes. This data is followed by a comma. 6. “s” is a single character representing the Longitude direction. s = E for East Longitude, s = W for West Longitude. This data is followed by a comma. 7. “n” is a single character representing the Quality indicator.
06 6 satellites being used 1.1 HDOP = 1.1 275.2,M Altitude = 275.2 Meters geoidal separation –33.0 meters -33.0,M Differential Correction Age= 6.0 seconds 6.0 Reference Station Identification 0133 Checksum *7B $GPGLL Message Format The $GPGLL consists of a string ASCII characters sent asynchronously at regular intervals. The string is sent at 9600 baud with eight data bits, one stop bit and no parity. The contents of this string are formed as follows: $GPGLL,ddmm.mmmmm,s,dddmm.mmmmm,s,hhmmss.
Example: $GPGLL,4451.84239,N,09128.00147,W,175612.00,A,D*78 $GPGLL message Header 4451.84239 Latitude 44 deg 51.84239 minutes N North Latitude 09128.00147 Longitude 91 deg 28.00147 minutes W West Longitude 175612.00 Universal Time 17 Hrs 56 min 12.00 sec A Status = valid data D Mode Indicator = Differential *78 Checksum $GPVTG Message Format The $GPVTG consists of a string ASCII characters sent asynchronously at regular intervals.
11. “*cc” is a three character string representing an asterisk followed by a two digit hexadecimal checksum. 12. The string is terminated by a carriage return and Line Feed. There will then be a short interval with no data transmission before the next string begins. Example: $GPVTG,186.55,T,187.35,M,0.13,N,0.24,K,D*25 $GPVTG message Header 186.55 True Course over ground 261.74 degrees T True Heading 187.35 Magnetic Course over ground 262.26 degrees M Magnetic Heading 0.
7. “s” is a single character representing the Longitude direction. s = E for East Longitude, s = W for West Longitude. This data is followed by a comma. 8. “zzz.zz” is a variable character string (minimum-4, maximum-6) representing the ground speed. 0.00 to 999.99 knots. This data is followed by a comma. 9. “ttt.tt” is a variable character string (minimum-4, maximum-6) representing the Track made good, referenced to true North.. 0.00 to 359.99 degrees. This data is followed by a comma. 10.
Optional RS-232 Digital Output The optional RS-232 output consists of a string of decimal ASCII characters sent asynchronously at regular intervals. Nominally, the string is sent at 9600 baud with eight data bits, one stop bit and no parity. The mating cable for the GGC is included. The RS-232 signal is referenced to signal ground. The frame rate is 10 strings per second. See Appendices A and B for information on how to change the unit for this output. The contents of a string are formed as follows: 1.
10. The string is terminated by a carriage return. There will then be a short interval with no data transmission before the next string begins. Example: G 161409.9 ↑ (1) -000.8 ↑ UTC (2) space +00.1 ↑ Bank angle (3) space 273.4 +028.9 ↑ Elev. angle (4) space ↑ Head. angle (5) space 4451.84413,N ↑ Velocity (6) space space 09128.
Specifications Attitude Range: Bank Range: Elevation Resolution: Accuracy: Static * Accuracy: Dynamic Heading Range: Resolution: Accuracy: Static * Accuracy: Dynamic Angular Rate Range: Roll, Pitch, Yaw Resolution: Scale Factor Accuracy: Bias: Roll, Pitch, Yaw Non-Linearity: Bandwidth: Noise: Acceleration Range: X, Y, Z Range: Forward, Lateral, Vertical Resolution: Scale Factor Accuracy: Bias: X, Y, Z Non-Linearity: Bandwidth: GPS Positioning Range: Latitude Range: Longitude Range: Altitude Resolution: Lati
Z Dimensions Z Handle X Z Y Figure 6 GGC-E101 Dimensions in inches Watson Industries, Inc.
Warning Rough handling, dropping, or miswiring this unit is likely to cause damage. DISCLAIMER The information contained in this manual is believed to be accurate and reliable; however, it is the user’s responsibility to test and to determine whether a Watson Industries’ product is suitable for a particular use. Suggestion of uses should not be taken as inducements to infringe upon any patents. WARRANTY Watson Industries, Inc.
Customer Service All repairs, calibrations and upgrades are performed at the factory. Before returning any product, please contact Watson Industries to obtain a Returned Material Authorization number (RMA). Return Address & Contact Information Watson Industries, Inc. 3035 Melby Street Eau Claire, WI 54703 ATTN: Service Department Telephone: (715) 839-0628 Fax: (715) 839-8248 email: support@watson-gyro.
Appendix A The following data items are available in the Optional RS-232 Digital Output. Their full-scale ranges are listed. See Appendix B for more information. Inertial Output Full Scale Decimal Time UTC 1 HHMMSS ±179.9º ±89.9º 0.0 to 359.9º ±9.99 G ±9.99 G ±9.99 G ±9.99 G ±9.99 G ±9.99 G ±99.9 º/s ±99.9 º/s ±99.9 º/s ±99.9 º/s ±399.9 Km/hr ±89.99999 ±179.
The Status Bits contain the following information: Bit Description (If Set) 0 Bank Error Flag 1 Elevation Error Flag 2 Heading Error Flag 3 System Error Flag 4 Velocity Error Flag 5 Ready Flag 6 Checksum Error Flag e.g.
Appendix B Determining and Setting Output Channels For Optional RS-232 Digital Output To determine which channels are present. Hook the unit up to your computer’s serial port. Use a terminal program to interface with the unit. Turn on unit. Wait for the startup message to appear on display. Hit the space bar twice within the first 5 seconds of turn on. Sometimes it takes a few tries to get the hang of this. Wait 15 seconds. Now the unit will take in keyboard commands.
Setting Output Format There are two output formats: Optional Decimal ASCII output – '_' Command. Standard output – '%' Command. To change the output format: Connect the unit to your computer’s serial port. Use a terminal program to interface with the unit. Turn on the unit. Wait for the startup message to appear on the display. Press the space bar twice within the first 5 seconds of turn on. Sometimes it takes a few tries to get the hang of this. Wait 15 seconds. Now the unit will take in keyboard commands.
