Application of inertial navigation systems for unmanned aircraft

The application of inertial navigation systems (INS) in unmanned aerial vehicles (UAVs) includes a number of areas covering autonomous flight, precise positioning, target tracking and navigation in complex environments. Specific application scenarios and key technical solutions are listed below:

1. Main functions of INS unmanned aerial vehicles

(1) Autonomous navigation and positioning

● INS provides fully autonomous navigation without the need for external signals and is suitable for environments with limited or interfering GPS signals.

● When combined with **GNSS (GPS/BeiDou)** to provide global positioning, INS is used for short-term compensation for GPS loss situations.

(2) Position control and stabilization

● INS measures the pitch, roll and heading angles of the UAV in real time to ensure smooth flight.

● INS data optimizes the flight control system (FCS) in situations such as wind disturbances or sharp turns.

(3) Tracking the target and completing the mission

● Targeting, cruising and precision attacks (e.g. military UAVs) can be achieved by combining INS with radar and vision systems.

● During mapping or reconnaissance missions, the INS ensures that the aircraft follows a predetermined route and reduces the number of errors.

(4) Combined navigation Increased accuracy of INS

● INS+GNSS: a common navigation scheme for long-range unmanned aerial vehicles.

● INS+Visual SLAM: for areas with limited GPS space such as indoor areas, forests, canyons, etc.

● INS+LiDAR: improved terrain sensing for mapping drones.

● INS+RTK: For centimeter-level positioning, suitable for high-precision applications such as agriculture and mapping.

2. Application of INS on various types of unmanned aerial vehicles

(1) Fixed wing UAV

● Suitable for long-range and wide-range cruising missions (e.g. border patrol, environmental monitoring).

● Combined INS+GNSS navigation: improves navigation accuracy during long flights and prevents drift due to loss of GPS signal.

● INS+ Optical Flow/Visual Navigation: Enhanced navigation capabilities for low-altitude or urban operations.

(2) Rotary-wing UAVs (multi-rotor, helicopter)

● Suitable for fine work (eg logistics, crop protection, urban inspection).

● INS+RTK-GNSS: Improved hovering accuracy for precise placement (e.g. pesticide spraying).

● INS+SLAM: Suitable for use in conditions where GPS access is limited, such as in warehouses or when inspecting the interior of buildings.

(3) Fixed-wing vertical takeoff and landing (VTOL) UAV

● Combining the advantages of airplanes and helicopters, it is suitable for difficult conditions (eg mountain reconnaissance, maritime patrol).

● INS+GNSS+barometer: improve stability during takeoff and landing and course tracking accuracy.

(4) Military drones

● High-precision INS (Fiber Optic Gyro/Laser Gyro) + GPS: Ensures accurate positioning even in conditions of strong interference.

● INS+Radar/IR: Advanced combat sensing capabilities, such as unmanned combat aircraft, unmanned reconnaissance aircraft.

3. Key technical solutions

4. Future directions

● high-precision miniature INS (e.g. MEMS IMU for consumer drones).

● INS technology with anti-jamming capability (improves navigation in GPS failure conditions).

● cable-stayed inertial navigation (the navigation technology of the future for long periods of time without drift).

Inertial navigation systems (INS) have become a core technology for unmanned aerial vehicles, and as sensors and algorithms evolve, INS will provide more accurate navigation in more challenging environments.