Aim

The primary aims of the project are to provide agribusiness, including forestry, with a low cost, versatile tool for stock, crop, vegetation and topographic monitoring. The project also provides an enhanced capability for organisations undertaking wildlife transponder tracking and to regional bush fire authorities for fire identification.

The UAV will also offer a low cost alternative to aircraft and helicopter surveillance tasks. Such tasks may include shark spotting and beach rescue, law enforcement, event monitoring and extreme weather observation.
 
The availability of lightweight electric propulsion systems for miniature radio controlled aircraft comprising of high efficiency brushless outrunner motors and lithium polymer batteries coupled with autonomous flight control systems with the capability of video downlink now available at reasonable cost has prompted interest in developing an UAV to fulfill these tasks.

Hardware

Airframe

The airframe is based on a commercially available 100” (Link to) Windrider flying wing of expanded polypropylene (EPP) construction. This is a proven flying wing design that has previously been adapted to electric power, large enough and with sufficient wing area to carry a reasonable payload as well as maintain a visible presence in the air.

The outer panels are detachable, reducing the airframe to a compact 1200mm wide package. Reassembly is rapid, the outer panels sliding onto carbon fibre spars and held in place with rare earth magnets.

The fuselage pod is attached to the underside of the wing by locating pins and nylon bolts and houses the propulsion system and avionics. The pod can be fitted with a fixed main and steerable nose undercarriage for operation from suitably flat open areas.

Propulsion System

The propulsion system chosen for the project is a commercially available advanced brushless outrunner electric motor, controlled through an electronic speed controller and powered by a matched, high capacity Lithium Polymer battery. A large diameter coarse pitch electric flight propeller chosen to give maximum flight duration provides thrust. The motor and prop is mounted in a pusher configuration at the rear of the fuselage pod. The flight battery is mounted forward in the pod and is readily accessible by removing the two wing bolts.

Avionics

Basic flight control is achieved using commercially available radio control equipment.

In Auto control mode, onboard sensors send altitude, airspeed, attitude and GPS information to the autopilot. This information is processed by the autopilot, which then autonomously flies the UAV according to its flight profile. Flight information, along with surveillance information from onboard cameras and sensors, is then transmitted via down link to the operators computer, giving real time information to the operator and interested parties. Changes to the flight profile can be effected by the operator via an uplink.

In Manual control mode, the UAV can be fully controlled using a commercial radio control transmitter. In manual mode, all surveillance and flight sensor information is available to the operator, providing the down link is active.

The UAV can be launched by a ground operator with an R/C transmitter then control assumed by a remote operator for the flight tasking. Control can then be handed back to the ground operator for retrieval after the tasking is complete.