RDR-3100 User Manual
8.4
NMEA Output Message
9
Calibration of DR
9.1 Self calibration of DR
RDR-3100 calibrates the Gyro bias and odometer scale using the information of GPS
satellites automatically. It also updates the position and azimuth using GPS navigation
information automatically. Customer is not required to calibrate the Gyro bias and
odometer scale factor. In respect to the position and azimuth angle, RDR-3100 DR
provides a protocol, which is used to calibrate the position and azimuth angle using
digital map.
9.2 Calibration Criterion
•Keep vehicle in static with 15 seconds at least after power on to retrieve gyro initial
bias
•During normal operation, the calibration of gyro and odometer scale take place
automatically during periods of good GPS reception.
9.3 Calibration of DR
using digital map information
The DR is used to output the navigation data when GPS signal is absent or poor. The
longer time of losing GPS signal, the Gyro precision and odometer would become
worse. The best way to have better DR performance is to use the digital map
information. Once the map matching completed, it could provide useful information
for DR algorithm to continuously output the accurate navigation information as
possible. The PROYRESET is designed for this purpose. Navigation application can
reset the DR position and COG especially when no or poor GPS signal occurs.
Because digital map provides very accurate and stable positioning information, to get
longer and more accurate DR output, please use PROYRESET to achieve it.
9.4 Gyro Electric Characteristics
Gyro Chipset
- Panasonic EWTS86
Operation voltage Range
- +5±0.25 V
25
