美海军研究生院（NPS' Advanced Robotic Systems Engineering Laboratory (ARSENL) ） 50 Autonomous UAVs in Flight

0. Reference

http://diydrones.com/profiles/blogs/from-zero-to-fifty-planes-in-twenty-seven-minutes

1. 主要研发人员

• Timothy H Chung
  https://wiki.nps.edu/pages/viewrecentblogposts.action?key=~thchung

• Kevin Jones
  https://www.youtube.com/user/kevinjones4642/videos

2 . 系统概况

2.1 飞机

• Ritewing Zephyr II 56" Base Kit
  http://www.ritewingrc.com/
  
  
  • EPO foam wings
  • dual Thunder Power 5000 mAh LiPo
  • approximately 45-50 minutes

2.2 机载设备和功能

• Pixhawk

  • 主要使用ArduPlane的控件
  • Firmware: flies a lightly-modified branch of ArduPlane

• ODroid u3 companion computer

  • 机载计算机完成航迹规划、本体控制和信息传递等任务。
  • running a stripped-down version of Ubuntu Linux
  • based on ROS
  • broadcasts pose and status to other planes and to the ground.
  • accepts commands from the ground
  • payload-directed path planning algorithms
    • kernel: effectively moving a carrot in front of the plane.
    • leader-follower
    • distributed search
    • sequenced landing

• Radio

  • 主要解决频段分离问题，在紧急时刻切入手动
  • 900 MHz telemetry radios
  • the default 915-928 MHz band was saturated.
  • split our available 902-928 MHz band into three equal-size sub-bands and place an equal number of planes into each sub-band.
  • place an equal number of planes into each sub-band.

• Wifi

  • 作为信息交互主要基于Wifi和MAVLink协议
  • primary link with the fleet is an ad hoc 802.11n wireless network
  • UDP + MAVLink
  • 信号为弱势时，系统从新配置每个分集的sub-band和Net ID
  • Each plane broadcasts its pose at roughly 8 Hz

• 总体配置
  

2.3 基本算法

• Leader-follower模式
  • 系统自动将每一组当前位置最靠前，高度最高的飞机作为Leader
• 自主顺序降落模式
  • planes order their landings according to altitude, lowest first, and each plane in sequence begins an autonomous landing
  • 在40m高度盘旋，之后进入下滑轨道
  • 所有飞机的降落点通过GPS设置为相同位置
  • 支撑文章Optimized transit planning and landing of aerial robotic swarms， ICRA2013
• 轨迹显示
  • Visualization in Gazebo using data captured in ROS on each payload
• 系统构架
  • 支撑文章Multi-UAV Software Systems and Simulation Architecture, ICUAS2015
• 仿真环境设计
  
  
  

2.4 具体参数

• 发射时间 27分钟39秒
• 51架飞机升空
• 发射间隔33秒
• 25架飞机一组，每一组高度差为15米
• 四个小时的准备时间
• 在9分45秒的过程中，实现飞机之间的协作飞行

3. 图像资料

• 准备过程和机架
  

• 发射过程和发射机构
  

• 团队成员
  

• 转载请注明出处。