Barnard Microsystems Limited

Developing Unmanned Aircraft Systems to benefit Mankind

Unmanned Aircraft Systems: Part 1 - Unmanned Aircraft Part 1

InView IV-05

InView IV-05 prior to take-off

Overview

The Unmanned Aircraft System (UAS) consists of an Unmanned Aircraft (UA) which is essentially a robot plane togther with a Ground Control System (GCS). The Unmanned Aircraft contains a flight control computer, precision navigation (GPS and an Inertial Measurement Unit) and flight control electronics, a low vibration engine (such as a Wankel engine) and a payload, such as a high resolution camera. The UA represents a new, cost effective and more environmentally responsible approach to aerial reconnaissance and geophysical survey work.

Any aerial application, in which the payload weighs less than an average adult male (say 85 Kgs, although the US military allows a “worst case”soldier weight of 136 Kgs) could be performed less expensively and in a more environmentally friendly way, through the use of an Unmanned Air Vehicle.

Unmanned Aircraft have an historical military presence, in the form of the German V1 flying bomb of Second World War vintage, followed by the modern turbine-powered cruise missile, such as the US Tomahawk cruisemissile shown below, made by Raytheon. There are also some differences between the V1, the cruise missile and the UAV: the Unmanned Aircraft returns for reuse. The early civilian Unmanned Aircraft was in essence a radio controlled aeroplane.

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Why is an Unmanned Aircraft also called a Remotely Piloted Aircraft?
  • There is a growing realisation that someone, called the "Pilot in Command", must always be in charge of an unmanned aircraft, even when it is flying on autopilot, possibly beyond line of sight, following a predefined set of GPS waypoints and performing tasks en route, such as taking photographs and / or measurements.

  • The "Pilot in Command" must be able to terminate the flight at any stage of the flight, or command the unmanned aircraft to return to base at any time during the flight.

  • While the InView is within radio link, the aircraft can be optionally piloted from the ground in Manual Flight Mode. Take-off and landing is typically performed in Manual Flight Mode.

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Examples of some earlier unmanned aircraft

Unmanned Aircraft - Part I

V1 "Flying Bomb"

Tomahawk cruise missile from www.raytheon.com

Characteristics of the above vehicles

V1 “Flying Bomb”

1944 – 45

Raytheon Tomahawk

1983 - present

Max speed

656

880

Max payload

850

454

Max range

330

1,104

Wingspan

5.3

2.67

An important parameter for military Unmanned Aircraft is their endurance time, whereas a prime parameter for civilian Unmanned Aircraft, especially those in use on survey work, is their range. For more interesting information on the history of Unmanned Aircraft, see http://en.wikipedia.org/wiki/History_of_unmanned_aerial_vehicles

The inexpensive Unmanned Aircraft can criss-cross a region, or, repeatedly patrol an area, for up to 30 hours at a time, under computer control, day and night, under almost any weather condition, in an environmentally sustainable manner. This makes it a compelling solution for all manner of aerial reconnaissance and geophysical survey work. A comprehensive overview of Unmanned Aircraft is provided in http://en.wikipedia.org/wiki/Unmanned_aerial_vehicle .

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Advantages of Unmanned Aircraft over manned aircraft
  • The UA can fly day-after-day, night-after-night , in dangerous weather conditions, for up to 30 hours at a time, on an accurate flight path, under computer control.
  • Since Unmanned Aircraft can follow a precise flight path, they can fly close to each other to complete a survey in far less time than would be required for a manned aircraft.
  • An advantage in using several Unmanned Aircraft is that an UA that develops a fault in any of its systems can be replaced by a back-up UA, ensuring the assigned task is always completed on time. Several Unmanned Aircraft can also measure data in thesame location in a survey, to provide quality data, by removing any instrument drift or errors.
  • It can fly safely at low altitudes, enabling high resolution aeromagnetic mapping.
  • Network Centric approach in which data from each UA in flight updates a server computer in real time, allowing users to view the latest information, via the Internet.
  • It costs less to buy, to fly, to operate, to land and to dispose of than a piloted plane
  • The UA is more environmentally friendly: it is small, uses less fuel, creates less CO 2 and is less noisy: 16 g/km fuel for a UA vs 152 g/km for a Cessna Skylane.

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Application space for Unmanned Aircraft

Unmanned Aircraft - Part I

Note the tremendous flight endurance for Unmanned Aircraft.

from http://www.ncgia.ucsb.edu/ncrst/meetings/20031202SBA-UAV2003/Presentations/Wegener1.pdf

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