New radar comes into its own when visible and thermal sensors are blind
A radar technology, described as waiting for an
application, is coming into its own because it operates in fog and dust. Under these
conditions, visible and thermal sensors are blind, but the millimetre wave radar can still
see.
The Australian Centre for Field
Robotics is developing radar sensors that exploit this capability for use in dusty,
rainy or misty conditions. For example, shovels and draglines that are used in open cut
mining should operate 24 hours a day. But when visibility is reduced, due to dust or
inclement weather, this is not possible.
A 3D imaging millimetre wave radar and its associated visualisation software is in the
final stages of integration and will be tested this month. It can operate out to a range
of 500m through thick mist or rain and can produce an image with an angular resolution of
just over one degree and a range accuracy of a few centimetres.
Similar technology is being applied underground to profile mined out cavities as they are
being filled with waste rock and concrete and to measure the amount of rock in ore passes.
As millimetre wave sensors can be small and lightweight, a prototype radar has been
developed for mounting in an unmanned airborne vehicle. This technology will allow the
unmanned airborne vehicle to navigate using features on the ground that can be seen by the
radar at night or through mist and rain, and maybe even to land autonomously.
The radar operates in the millimetre frequency wave band that spans the decade between 30
and 300GHz, or a wavelength between 10 and 1mm. This region is characterised by steadily
increasing atmospheric attenuation interspersed with absorption peaks and so-called
‘windows’ as shown in Figure 1. When compared to the clear air attenuation in
the near infrared and at visible wavelengths, the millimetre wave band performs poorly.
However, when visibility is poor and thermal sensors are blind, the millimetre wave radar
can still see.
These developments aren’t bad for a technology that languished through the latter
part of the 20th century awaiting a killer application.
Figure 1: Atmospheric absorption of electromagnetic radiation |
Open cut mining visualisation radar
 Typical 3D topological image produced by visualisation radar
Unmanned airborne vehicle with transparent
nose to house the millimetre wave imaging radar
Imaging radar and gimbals |
DIARY DATES
April to July 2002
A series of ICT Cluster Forums,
on Thursdays at 8.30 for 9.00 am
Contact Fiona Hearne
4 April Microelectronics Cluster
2 May Photonics & Opto-electronics
23 May Electronics Manufacture Cluster
13 June Embedded Software/Software Cluster
4 July New Media Cluster
Venue: NSW Trade &
Investment Centre, Grosvenor Place, 225 George Stree, SYDNEY
May 2002
2002 Innovation Lecture
"Why is it so difficult to develop great ideas and inventions in
Australia: Australians can make it".
The 2002 Innovation Lecture by Dr Jim Fox, Managing Director, Vision Systems Limited, Dr
Fox has particular expertise in establishing and building international, technology based
businesses.
8 May : Melbourne - Vision Systems, Mt
Waverley, 6pm for lecture and cocktail reception
9 May : Sydney - The Regent Hotel, 6pm for lecture and cocktail
reception
Sponsored by: AusIndustry, Baldwin Shelston Waters & Macquarie Bank
Contact Fiona Hearne
Sustainable Transport in Sustainable Cities - May 2002
Launch of the Sustainable Transport in Sustainable Cities
project report and recommendations.
For information and registrations, Contact Fiona
Hearne
4 - 6 September 2002
Computers in Manufacturing Expo 2002
Sydney Convention & Exhibition Centre Darling Harbour
www.cimexpo.com.au
contact Jeremy Nathan
ttelephone (02) 9319 3099, email Jeremy.Nathan@industracom.com
Fiona Hearne can be
contacted by email by clicking on the links above or by phone on (02) 93517205 or fax on
(02) 9351 2012.
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