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Abstract This project designed and implemented a platform for use in a system of unmanned aerial vehicles (UAVs) capable of human assisted- autonomous and fully autonomous flight for search and rescue applications to improve the speed, efficiency, and safety of search and rescue to benefit both the victims and the rescuers alike. To accomplish this, the platform was designed to be lightweight with long endurance, equipped with specialized search and rescue sensors, and utilizes the paparazzi autopilot system, which is an open source, Linux based autopilot package for flight stability and autonomous control. This project worked in conjunction with two other WPI MQPs, an AI/Image processing team and a communications team, as well as two teams from the University of New Hampshire, which built the communications hardware and UI, to realize the full system, including inter-UAV communications, high level search algorithms and ground control station with a user interface. Project Goals •Three fully autonomous fixed wing aircraft •Interface with the UAV controlling search algorithm •Autonomous flight based on GPS waypoint navigation •UAVs containing a pan tilts camera gimbal •UAVs capable of: •carrying a payload of 10 lbs. •flying at a cruising speed of 35 – 55 mph •flying between 120 ft. and 400 ft. in altitude •maintaining flight for a minimum of 1 hour •supplying 120 watts of power during inter flight to on board electronics Special Thanks: Design of an Autonomous Platform for Search and Rescue UAV Networks Controlling the UAVs To control the UAVs our team used the Paparazzi Open Source Linux based autopilot system. The system features a ground control station software package for controlling the UAVs and for data acquisition and display. . Autopilot Simulation Testing the airframe required a lot of time and proper weather, simulations of the autopilot system were key for understanding Autopilot Manual Flight Data Acquisition . how the system responds to user input and what to expect from the UAV. The above simulations demonstrate the effect of changing the proportional and derivative constants for the control loop affecting the controlling the target position of the elevator while examining the altitude of the UAV. Center of Gravity Center of Gravity Battery Battery Gas Tank Gas Tank Flir Tau Ignition Ignition Autopilot Sony Block Panda/Beagle Intel Atom Camera Gimbal Image with Dampening Image with out Dampening Flight Test Results . D Goal Outcomes Resulting Changes Nov 13 Robin RC Flight -During Aggressive climbs the plane pulled to the right -Engine had a non-linear response to throttle control -Engine stalled in final flight -Altered engine mount thrust angles and pressure gas tank -Changed rudder servo to faster one, and replace horns -Moved the gas tank back 4 inches -Moved the throttle servo forward Feb 2 Robin RC Flight -Successful GPS downlink -Nipple of muffler melted off -Wings shifted and sheered off wing struts connection -Wing strut replaced with stronger alternatives -Reduced the throw of the control surfaces -Added Aluminum Frame and hard mount point for wings -Mounted the IR sensors Feb 9 RC Flight Decoder Board -Calibrated thermo sensors on plane -Sideways landing broke wheel -Re shrunk the monokote -Replaced the broken wheel Feb 15 Auto 1 -30 cc engines broken in -Found we couldn’t or fly strait -Lost the down link before going into Auto 1 -Fixed the torqued wing -Fixed the orientation of the wheels -Added New decoder board Feb 18 Auto 2 -New decoder board interprets signals differently -caught a cross wing and crashed -Fixed all crash damage, replaced glue on tail and installed the dome -Calibrated new decoder board Apr 7 Jay Flight Auto 1/2 - Too windy, taxi test only -NA Apr 11 Jay Flight Auto 1/2 -Jay flew, slight warp in right wing discovered -Only Half of Robin returned - to be continued….. 37.12 37.24 37.34 37.39 37.55 Catherine Coleman (ME/RBE), Joseph Funk (ECE), James Salvati (RBE/ECE), Christopher Whipple(RBE) Advisors: Professors Taskin Padir, PhD (ECE), Alexander Wyglinski, PhD (ECE) Tanner Hiller Airport Richard Gammon, RC Expert Professor John Hall Professor Taskin Padir Sterling Airport Professor Fred Looft Professor Ken Stafford Professor Alexander Wyglinski The images to the left illustrate how we used CAD to balance the airframes to ensure stable flight with all components installed. The top image is the complete airframe with all components from all 3 teams, while the bottom image is a simple arrangement with just the components necessary for flight. Modeling the UAVs Testing the UAVs We tested the UAVs at the Tanner Hiller airport in Barre, MA. The radio control setup used was a DX6i and was used in conjunction with the autopilot as the FAA mandates that all UAVs have a manual override. The images to the left were taken at test flights at Tanner Hiller airport. The top image is of Robin during the November 2011 test flight and the bottom image is of Jay during the April 11, 2012 test. To maximize our camera’s view we put each on a pan- tilt gimbal system. This system was also designed to reduce the vibrations from the engine to the camera.
