With the development of The Times, unmanned aerial vehicles (uavs) have emerged in various countries in the world. Their advantages of easy to use, simple structure and safe and stable make them a hot research topic. The uav senses the changes of surrounding parameters through sensors, and constantly makes decisions to change its attitude through the operation of the controller, so as to fly safely and stably. Among these sensors, the barometer is very important.
The application fields of uavs can be divided into three categories: military, civil and consumer. These three categories have different requirements for uavs' sensors. Military uavs require higher sensitivity, accurate speed and height, and intelligent control equipment. Compared with civil uav, the requirements of speed, height, accuracy and requirements of travel are relatively low, and the sensor is not too high. Consumer drones are generally used for entertainment and aerial photography, which is generally not expensive and USES multiple rotors.
Various technologies of uav have been developed to the common people, and the trend of uav industrialization has been popularized. China's uav technology started relatively early and has been making progress and development. Drones can often be seen in the air in cities. Foreign countries have used drones to deliver express delivery and other businesses. These applications are inseparable from uav attitude sensors. Although unmanned aerial vehicle (uav) has been popularized, its control technology still has some difficulties. The flight control system is a very important part of the uav, which requires a high degree of accuracy, and for more stable flight, the role of sensors is necessary. The flight control subsystem is the core system of uav, which generally includes three parts: sensor, airborne computer and servo actuating equipment. The realized functions mainly include uav attitude stability and control, uav mission equipment management and emergency control. At the same time, the hardware industry chain is becoming more and more mature, and the decrease of hardware cost creates opportunities for the further popularization of uav technology. In recent years, the rise of the uav market has a lot to do with the reduction of cost and the maturity of technology. The 6-axis and 9-axis inertial sensors also gradually replaced the single sensor, further reducing the cost and power consumption. The GPS chip weighs just 0.3 grams and costs less than $5.
A barometer is an instrument for measuring atmospheric pressure, based on torricelli's experimental principles. In drones, a barometer is a sensor that USES atmospheric pressure to indicate flight altitude. Altitude is the most basic parameter of uav flight, which is the basis of safe flight and successful completion of various tasks. In addition, it is of great significance for accurate height measurement to save energy consumption, give full play to the function of uav, and smooth flight. Traditional air pressure altimeter can not be applied to uav well, for one thing, it is large in size and complicated in mechanism, and the other is that the accuracy of measurement can not meet our requirements. However, with the continuous development of measurement technology, semiconductor integrated circuit and piezoresistive pressure sensor can be highly integrated, with simple interface, small size, high stability, fast dynamic response, high precision and sensitivity, which will greatly improve the comprehensive performance of the system and simplify the system structure.
Because the sensor sends out analog signals, in order to avoid the interference of digital signals, we use the filter circuit to improve, after filtering the signal through amplitude modulation, we can get the standard signal we need. In addition, due to different levels of noise, we need to consider barometer accuracy of output signal, after filtering, amplitude modulation signals and a standard voltage signal through the instrument using the differential amplification signal amplifier, and then send to detail controller for processing, to expand the scope of the signal and improve the sensitivity of the system. At the same time, the barometer of the attitude sensor of uav has the advantage of instrument, which USES very little energy during operation and reduces the temperature drift. The precision inside the instrument makes the user satisfied. In addition, the instrument amplifier has a special filter inside, can largely eliminate the noise.
With the development of The Times, drones will become more popular and will enter every household in the future. Its attitude sensor development and progress will also bring greater benefits and results. Although the attitude sensor still has low precision and real-time problems, but through continuous innovation, the sensor will continue to improve and mature.