ISNAV

General Information

ISNAV

The ISNAV vehicle navigation system is GMV’s advanced navigation and time reference solution for military vehicles. ISNAV provides data on position, velocity, attitude, and time in a variety of formats to offer an integrated navigation and synchronization solution. The ISNAV system is designed to include the Galileo receiver from the public regulated service (PRS) PRESENCE 2 and can integrate an inertial navigation system (INS). The ISNAV system time server can be expanded to provide synchronization signals in a variety of formats, such as IRG-B and HQ.

Milestones

The Spanish Defense Ministry has chosen ISNAV for its VCR 8x8 program.

Multi-constellation technology, compatibility with PRS, and external INS provide a robust navigation and immunity from identity theft.

The ISNAV system can also be used as a time source for the vehicle network.

ISNAV’s modular design makes it possible to adapt it to several external INS units and to the different requirements of the mission systems.

ISNAV allows the distribution of pointing data, making the system independent of the INS unit of the part or vehicle.

ISNAV System Features

ISNAV, an advanced modular navigation system

Navigation Data

The navigation data provided by ISNAV is the result of combining hybridized multi-constellation GNSS navigation with inertial data from an external INS or an internal IMU, specifically:

Position: latitude, longitude, and altitude
Velocity: horizontal, drift angle, and vertical
Attitude: pitch, yaw, and roll
Time: UTC and local
NTP server
1PPS signal
Optional: time distribution module with IRIG-B, HQ signals, and high-stability oscillator for time propagation in the absence of the GNSS signal

The navigation data are distributed following a proprietary protocol and the NMEA 0183 v.4.1 standard.

Compatibility with INS/IMU

The system is designed to include an external INS to provide resilient navigation. The characteristics of this external INS can be adjusted to the final application. Compatibility with different COTS INS is guaranteed and communication is carried out with a customizable harness, which includes the following in its standard configuration:

28 V power source for the INS
1 1PPS output to synchronize the INS
1 CAN (J1939) output for the odometer data
2 high-speed serial ports (RS422)

The system can also be configured to use an internal IMU unit and remove the external INS. The internal IMU data is integrated in a firmly attached navigation filter.

Interfaces

The system provides standard ports for communication with the vehicle network. The standard configuration includes:

2 Ethernet 10/100 I/O cables (redundant)
1 CAN (J1939) input
1 GNSS RF (TNC) input
1 auxiliary GNSS RF (TNC) output
1 1PPS output
5 discrete configurable outputs
2 discrete configurable inputs
1 maintenance port (RS422)

Other port configurations can be added on demand.

System Qualification

The system is completely qualified for the standard military ground vehicle environment, as well as to fulfill the electrical and electromagnetic requirements:

28 V power source: MIL-STD-1275E
Temperature: C1 (intermediate cold) and A1 (extreme heat), AECTP-200-4
Humidity: MIL-STD-810G (M. 507.5 P. II)
Fungus: MIL-STD-810G
Corrosion: ISO 9227:2012 (240 h)
Vibration: MIL-STD-810G (land vehicle)
Shock: MIL-STD-810G (collision danger shock test)
Rain: MIL-STD-810G (M. 506 P. III)
EMI/EMC: MIL-STD-461F
Connection/Grounding: MIL-STD-464C

Lightning protection: DO-160E, section 22, level 4

Documents

These documents are related to the ISNAV system:

GMV's ISNAV