SPAN TECHNOLOGY
SPAN (Synchronous Position, Attitude and Navigation) technology brings together two
complementary technologies: Global Navigation Satellite System (GNSS) positioning
and inertial navigation. The absolute accuracy of GNSS positioning and the stability of
Inertial Measurement Unit (IMU) gyro and accelerometer measurements, combine to
provide an exceptional 3D navigation solution delivering full attitude and orientation.
SPAN LAND VEHICLE OVERVIEW
NovAtel’s SPAN Land Vehicle technology optimizes the integrated GNSS+INS
performance for fixed wheel land vehicles under low dynamics, in urban canyons,
or during extended GNSS outages. Accurate position, velocity and attitude are
maintained in these challenging environments through our intelligent vehicle dynamics
modeling and the use of NovAtel’s patented Antenna Phase Windup technology.
EXTENDED GNSS OUTAGE
During periods of extended GNSS outage, the INS solution can dri significantly
without the GNSS position to correct for the accumulation of IMU errors. The
intelligent vehicle modeling in SPAN Land Vehicle technology identifies IMU errors and
reduces the impact of those errors on the SPAN solution.
TABLE 1: AVERAGE SPAN LAND VEHICLE PERFORMANCE AT 1 HOUR COMPLETE GNSS OUTAGE
1
IMU Grade Average Error Over Distance
Traveled (%) Over 1 Hour
Azimuth Error (degrees) 1 Sigma
Standard Deviation
Land Profile Land Profile
with DMI
Land Profile Land Profile
with DMI
Entry Level–S1 0.28% 0.15% 1.76 1.59
Mid-Range—S2 0.10% 0.05% 0.18 0.17
High Performance–S3 0.08% 0.05% 0.12 0.10
1. Typical driving conditions at an average speed of 65 km/hr.
Firmware SPAN
®
Land Vehicle
OPTIMIZES SPAN PERFORMANCE
IN FIXED WHEEL LAND VEHICLE
APPLICATIONS
+
Continuous position, velocity and
attitude output through extended
GNSS outage
+
Enhanced navigation performance
in low dynamic applications
+
SPAN intelligent vehicle dynamics
modeling
+
Patented Antenna Phase Windup
Technology
+
Available for all SPAN supported
IMUs
If you require more information about
firmware, visit www.gnss.ca
BENEFITS AND FEATURES
SPAN
®
Land Vehicle
LOW DYNAMICS APPLICATIONS
INS systems rely on changes in accelerations and rotations to determine velocity and
heading. In applications with a constant direction and speed, such as those commonly
found in agriculture, mining and machine control, it is dicult for an INS system to
dierentiate IMU errors from actual measurements. In a GNSS+INS system, GNSS
positioning can constrain position and velocity errors, but cannot correct errors in
attitude measurements.
SPAN Land Vehicle technology uses NovAtel’s patented Antenna Phase Windup
technology to sense changes in direction and, when combined with intelligent vehicle
modeling, can correct for IMU errors in attitude.
ADDING EXTERNAL SENSORS
By adding external sensors to the system, such as a Distance Measurement
Instrument (DMI), dual antennas or any other external position, velocity or attitude
input, SPAN Land Vehicle technology can be further improved. The plots below show
the performance for each grade of IMU over a 1 hour period.
FIGURE 1: ERROR OVER DISTANCE TRAVELED OVER 1 HOUR OF COMPLETE GNSS OUTAGE
To obtain the latest data regarding this
product, visit www.gnss.ca
/
gnss.ca
sales@gnss.ca
1-855-OEM-GNSS (U.S. and Canada)
or 778-430-5999
China 0086-21-68882300
Europe 1-855-636-4677
SE Asia and Australia 1-855-636-46771
Version 1 Specifications subject to change without notice.
©2017 NovAtel Inc. All rights reserved.
NovAtel and SPAN are registered trademarks of NovAtel Inc.
D22535 April 2017
Printed in Canada.