CanberraUAV

Design

A more compete overview of our hardware and systems is available as our Deliverable 1 Report [ https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0BxJBg_6KSZ5zOTk0ZWUxOTUtYWI1Zi00OGU4LTk1YmUtMTgwN2Y3OTg0ODky&hl=en_US ] for the UAV Challenge.

Our Deliverable 2 [ https://docs.google.com/open?id=0BxJBg_6KSZ5zRzU3N0JCN3RHT2M ] and Deliverable 3 [ https://docs.google.com/open?id=0BxJBg_6KSZ5zeGE5Z09QQTZYWmc ] are also available. These show our risk management, design and flight testing.

Airframe

Cyber Technology [ http://www.cybertechuav.com.au/ ] Cyberhawk. This aircraft is a rugged UAV, designed for imaging and search type missions. It has a Desert Aircraft 50cc single cylinder engine driving a "pusher" propellor and an alternator providing plenty of on-board power.

The advantage of a "pusher" propellor is the exhaust from the engine is behind the main body and thus will not obscure the vision of a camera mounted in that section.

Autopilot

Our major autopilot software is the Ardupilot [ http://diydrones.com/profiles/blogs/ardupilot-main-page ], an open source UAV controller. The advantages of this system is twofold: First, we can modify the source code to fit our requirements. Secondly, it has been well tested by many hobbyists around the world and on a variety of platforms, giving it a great deal of ruggedness and reliability. This is combined with a custom failsafe device based on the Arduino plaform, which terminates the flight is the UAV breaches one of several flight safety conditions.

Cameras

Point Grey [ http://www.ptgrey.com/ Chameleon ]. This is a small form factor 1.3 megapixel greyscale camera. It is designed for machine vision applications, having a high shutter speed, optical stablisation and a high sensitivity CCD. We are using a single colour Chameleon.

Image Processing

Pandaboard [ http://www.pandaboard.org/ ]. This is an ARM platform boasting a Dual-core ARM Cortex-A9 MPCore processor, 1 Gb RAM and onboard USB, Wifi and Ethernet. This runs a basic Linux distribution on an attached SSD and performs all image capture and processing.

Radios

We are currently using three radio systems. The primary link is a 5.8 GHz Ubiquity Bullet radio, which can carry our telemetry and image streams. There is a 900 MHz low-bandwidth link that acts as a backup telemetry link. For manual override of the UAV's controls, we are using a standard 2.4 GHz RC controller.

MAVProxy [ http://git.samba.org/?p=tridge/UAV/MAVProxy.git;a=summary ] is our main ground control station, along with qGroundControl [ http://qgroundcontrol.org/ ] for monitoring all aspects of the UAV's progress and system status. They are open source and multi-platform, enabling us to customise the applications to our needs quickly and easily.

Simulation and Testing

We are using a HIL (Hardware in Loop) simulation setup using FlightGear [ http://www.flightgear.org/ ], qgroundcontrol and MAVLink [ https://github.com/pixhawk/mavlink ] to test the Ardupilot before putting it in the air.

We have several small "crash resistant" test aircraft in our hangar for field testing. This includes a Skywalker [ http://diydrones.com/profiles/blogs/strong-epo-foam-skywalker-uav ] and Telemaster [ http://www.diydrones.com/profiles/blogs/a-senior-telemaster-as-an-apm ].

We have a larger airframe - the Beaver - for testing combined systems together. It is capable of carrying all our our equipment for extended periods of time.

Copyright 2012