Home > news > Content
Fiber Optic Gyro North Finder
- 2019-06-17-

Nowadays, with the development of chips, fiber optic gyro north finder and big data technology, drones have begun the trend of intelligence, terminalization and clustering, so that drones fly into the ordinary people from military applications far away from people's vision. Family. It is undeniable that the development of flight control technology is the biggest driver of drone changes in recent years.

The Flight Control System is called the flight control and can be regarded as the brain of the aircraft. Multi-axis aircraft flight, hovering, attitude change, etc. are all carried out by a variety of sensors to transfer the aircraft's attitude data back to the flight control, and then by the flight control through the calculation and judgment of the command, the actuator completes the action and flight attitude adjustment .

The current flight control uses an IMU consisting of a three-axis gyroscope, a three-axis accelerometer, a three-axis geomagnetic sensor and a barometer, also known as an inertial measurement unit.

Three-axis gyroscope, three-axis accelerometer, three-axis in the three-axis geomagnetic sensor refers to the left and right sides of the aircraft, and the three axes above and below the vertical direction are generally represented by XYZ. The left and right direction is called the roll in the airplane. The front and rear directions are called pitch in the airplane, and the vertical direction is the Z axis. The earliest gyroscope was a high-speed rotating gyro. The gyro was fixed in a frame by three flexible axes. No matter how the outer frame rotates, the high-speed rotating gyro always maintains a posture. Data such as the degree of rotation of the outer frame can be calculated by the sensors on the three axes.

The most basic function of the flight control controls the balance of an aircraft when flying in the air. It is measured by the IMU. The current inclination data of the perceived aircraft is compiled into an electronic signal by the compiler, and this signal is transmitted to the internal control unit of the flight control through the signal. The MCU is responsible for the calculation. According to the current data of the aircraft, a compensation direction and a compensation angle are calculated. Then the compensation data is compiled into an electronic signal and transmitted to the steering gear or the motor. The motor or the steering gear executes the command to complete the compensation. Action, then the sensor senses that the aircraft is stable, and the real-time data is sent to the MCU again. The MCU will stop compensating the signal, which forms a cycle. Most of the flight control is basically an internal cycle of 10HZ, that is, 10 times in 1 second. .

Due to the current level of sensor design, the data measured by these sensors will produce certain errors and may be disturbed by the environment, thus affecting the accuracy of state estimation. In order to ensure flight performance, it is necessary to make full use of each sensor data to fuse 15 states with high credibility, namely integrated navigation technology. The integrated navigation technology combines the advantages and disadvantages of GPS, IMU, barometer and geomagnetic compass. Through the technology of electronic signal processing, the measurement values of various sensors are combined to obtain more accurate state measurement.

In order to improve the perception and flight performance of aerial drones, in addition to the above basic sensor solutions, mainstream UAV products now incorporate advanced vision sensors, ultrasonic sensors and IMU and compass redundant navigation systems. The binocular stereo vision system calculates the three-dimensional position of the object based on the continuous image, and provides positioning and speed measurement in addition to the obstacle avoidance function. The ultrasonic module below the fuselage plays the role of auxiliary height, while the redundant IMU and compass automatically switch to another sensor when one component is disturbed, which greatly improves the reliability of the integrated navigation.

The intelligent navigation system introduces multiple sensors, greatly increasing the amount of data and complexity, and performing multiple system reconstructions for navigation and flight control algorithms for vision and sensors, adding new software modules and architectures, and improving flight performance and reliability. Sex.