Deciphering the key technologies of drones

Various drones, such as the Tupolev Tu-141, Turkish TB-2, Switchblade cruise missiles, Laleka-100, Poseidon II, and Corvo, have different performance and characteristics and undertake different combat missions including reconnaissance, surveillance, strike, and defense.

Key technologies of drones

A "lump of iron" can have so many functions, which can be said to be a collection of countless "black technologies". Aerodynamic technology, aviation material technology, navigation, guidance and control technology, avionics and electrical technology and many other technologies are fully reflected in drones. Among them, navigation, guidance and control technology is one of the most complex technologies in drone systems and is the core area of drone research and development and application. This technology ensures that drones can fly according to the predetermined path, accurately perform tasks and remain stable in various environments. How to understand this technology?

Navigation technology

The drone needs to obtain information such as its position, speed, acceleration, attitude, attitude angular velocity, etc. in a specified reference frame. In other words, it needs to know where it is and its attitude.

Guidance Technology

The drone discovers the target by itself or inputs the target's location, speed and other information through external information. Based on its own location, speed, status and external environment, it obtains the attitude and speed to reach the target through flight performance calculation, or how to avoid obstacles on the route according to map planning, so as to ensure that the drone flies along the predetermined path and reaches the destination accurately. In other words, it knows where the target is and how to reach the target. 

Control technology

Control technology is the key to ensure the stability and maneuverability of the drone. It involves aspects such as attitude control, altitude control, speed control and direction control of the drone. Control technology is achieved by using a flight control system and actuators (such as motors, servos, etc.). The flight control system receives data from the navigation system and guidance system, and calculates the necessary control signals based on these data to adjust the attitude and flight status of the drone. The actuator performs corresponding actions based on the control signal to ensure that the drone flies according to the control instructions. In other words, change the flight attitude and follow the guidance instructions.

Navigation and guidance sytems are both for control services. In addition to providing the position, speed, and attitude information required for navigation, the built-in gyroscope sensor has a zero bias stability of up to 1°/h, which can directly generate the line of sight angular rate of the target through coordinate transformation and participate in the guidance calculation.

Switchblade UAV

Currently, most drones use INS/GNSS combination as the basic method for navigation, guidance, and control. The relative attitude angle and relative position of the drone are calculated based on the angular rate and acceleration data measured by the gyroscope and accelerometer, that is, the speed, position, and attitude angle of the body relative to the inertial reference system can be obtained without external information, thereby realizing the functions of navigation, guidance, and control. Taking the Hitech Sensors' attitude reference system as an example, the product can output an attitude accuracy index of ≤0.3° (2σ, dynamic) in the combined navigation mode. Under GNSS denial conditions, it can still provide continuous high-precision attitude. After multiple actual measurement data verification, the attitude error is less than 3° in the pure inertial attitude mode for 6 consecutive hours.