A lightweight autonomous MAV for indoor search and rescue

Micro Aerial Vehicles (MAVs) have great potentials to be applied for indoor search and rescue missions. In this paper, we propose a modular lightweight design of an autonomous MAV with integrated hardware and software. The MAV is equipped with the 2D laser scanner, camera, mission computer and flight controller, running all the computation onboard in real time. The onboard perception system includes a laser‐based SLAM module and a custom‐designed visual detection module. A dual Kalman filter design provides robust state estimation by multiple sensor fusion. Specifically, the fusion module provides robust altitude measurement in the circumstance of surface changing. In addition, indoor‐outdoor transition is explicitly handled by the fusion module. In order to efficiently navigate through obstacles and adapt to multiple tasks, a task tree‐based mission planning method is seamlessly integrated with path planning and control modules. The MAV is capable of searching and rescuing victims from unknown indoor environments effectively. It was validated by our award‐winning performance at the 2017 International Micro Air Vehicle Competition (IMAV 2017), held in Toulouse, France. The performance video is available on https://youtu.be/8H19ppS_VXM .     

微型飞行器的研究与发展

微型飞行器是90年代中期出现的新生事物，它正以日新月异的速度蓬勃向前发展。它的出现引起了世界各国的极大关注和高度重视。本文介绍了微型飞行器的概念和应用前景，重点综述国内外研究现状，总结出研究的关键问题，并提出了未来微型飞行器研究发展的趋势。     

Modeling and global trajectory tracking control for an over-actuated MAV

This paper deals with an original micro aerial vehicle (MAV) design, the Omnicopter MAV. It has two central coaxial rotors with fixed-pitch propellers and three perimeter mounted ducted fans with servo motors performing thrust vectoring. Compared with traditional rotary wing MAVs that have inherent underactuation, the Omnicopter possesses some advantages in mobility, for example, lateral translation with zero attitude and hover with nonzero attitude. The trajectory tracking control design, global stability analysis, and control allocation are demonstrated through numerical simulation. The advantage of zero attitude translation is illustrated through experimental results.     

Low-Power Operational Amplifier for Real-Time Signal Processing System of Micro Air Vehicle

A low-power complementary metal oxide semiconductor(CMOS) operational amplifier (op-amp) for real-time signal processing of micro air vehicle (MAV) is designed in this paper. Traditional folded cascode architecture with positive channel metal oxide semiconductor(PMOS) differential input transistors and sub-threshold technology are applied under the low supply voltage. Simulation results show that this amplifier has significantly low power, while maintaining almost the same gain, bandwidth and other key performances. The power required is only 0.12mW, which is applicable to low-power and low-voltage real-time signal acquisition and processing system.     

翼型绕流的LBM大涡模拟研究

文章针对微型飞行器不可压、低雷诺数、非定常的运动特点,应用格子玻尔兹曼大涡模拟(LBM-LES)方法,对NACA0012翼型在0°攻角,雷诺数为1×105情况下,计算了升阻特性。采用格子玻尔兹曼边界插值方法处理曲线边界和动量交换方法计算升力、阻力。计算结果表明,该方法可以预测翼型非定常的升力、阻力变化以及低雷诺数涡脱落现象,因而,该方法对于微型飞行器流场计算是一种可用的计算手段。     

微扑翼飞行中的生物和仿生力传感器述评

随着昆虫飞行机理和仿生扑翼飞行研究的不断进展,理解昆虫的传感系统并研制适于微型扑翼飞行器的仿生传感器逐渐成为目前关注的焦点,而MEMS的快速发展使得研制新型的仿生微型传感器成为可能。简要介绍仿生扑翼飞行中传感系统研究现状,对昆虫飞行中采用的力传感器原理、分类进行了介绍;重点分析了几种典型的力传感器;归纳和总结了基于昆虫毛状传感器、钟状传感器和平衡棒仿生,采用各种MEMS技术研制的微型力传感器的生产工艺和应用特点;探索和展望了仿生力传感器的发展特点和今后的发展趋势。     

基于MEMS加速度传感器的双轴倾角计及其应用

利用MEMS加速度传感器设计了双轴倾角计,并采用单片机进行了线性化和温度补偿,倾斜角以模拟量和数字量2种形式输出。该倾角计体积小、重量轻、精度高,能够很好地满足MAV姿态控制及其他应用的倾角测量。     

A Ducted Fan MAV Anti-torque Control System

The UAVs （unmanned aerial vehicles） exist in various sizes. One of the most interesting niches concerns the UAVs of moderate size （〈 1 m）, also called MAVs （micro air vehicles）. An aerodynamic study of the ULB （Universite Libre de Bruxelles） developed a ducted rotor MAV using the results of full-scale wind tunnel tests that allowed the determination of the platform speed envelope, the power requirements and the endurance characteristics for ISA sea level conditions. Although the ULB MAV appears similar to other ducted-rotor concepts, it fundamentally differs from them as it uses the downwash of a single rotor to compensate the electric motor main rotor torque and to achieve full control around the roll, pitch and yaw axes. This paper explains in detail the components layout of the MAV and the aerodynamic characteristics of the anti-torque blades.     

高速摄像技术在微型旋翼机性能测量中的应用

提出了一种测量微型旋翼机桨距角及弹性连杆变形角度的新方法—高速摄像法。这种方法可以准确地测得高速旋转物体的角度,拍摄速度可达15 000帧/s。实验需要处理两个角度——桨距角和弹性连杆变形角度。实验中,首先对拍摄部位进行预处理,然后对微型飞行器在高速旋转时的不同状态进行拍摄,包括从正面拍摄桨距角和从侧面拍摄弹性连杆的变形角度,对拍摄到的图片进行筛选、存储并进行图像处理。图像处理部分是用MATLAB软件进行边缘检测,对比了四种不同的检测方法的效果,最后采用Canny算法。用最小二乘法拟和成直线,得到所需的角度;利用采集电路将角度与电压实时地对应起来,得到了电机电压和桨距角及弹性连杆变形角度的八组关系曲线,并对得到角度的精度进行了分析。实验证明这种方法在微型飞行器高速旋转时信号弱、干扰强、其动态特性难以精确测量情况下,可有效测量微型飞行器的变距角度。     

一种基于图像信息的微小型飞行器姿态测量方法

提出了一种基于图像信息的微小型飞行器姿态测量方法.该方法综合运用Laplacian-Gauss边缘检测、OTSU算法以及Hough变换等数字图像处理技术,从机载摄像机图像中识别出地平线或者海天线.根据得到的直线信息可以迅速地测量出飞行器的滚转角与俯仰角.实验表明,该方法可以有效地识别出复杂背景中的地平线和海天线,计算得到的滚转角与俯仰角精度满足飞行器的姿态控制要求.