SonarMite Echo Sounder
'SP' = Serial Port version
'BT' = Serial + Bluetooth version
The SonarMite Echo Sounder is the result of nearly two years research and
development to further extend the boundaries of shallow water hydrographic
surveying equipment. The introduction by Ohmex in 1997 of the SonarLite, the
worlds first truly portable echo sounder system, has been a hard act to follow
and it remains the portable instrument of choice in many survey companies around
the world. The release of the SonarMite instrument marks the next stage
introducing a series of equipment designed around the WinSTRUMENT concept using
the latest portable computers integrated with new measurement technologies.
SonarMite Main Features
 | Bluetooth technology integrated with Windows Pocket PC devices |
| Proven 'Smart' transducer design with QA output |
| Internal rechargeable battery for all day use in the field |
| Easily integrated with other modern software and GPS technology |
Throughout the Hydrographic world the term 'Black Box' has become a euphemism
for a device that has a minimal user interface and normally requires connection
to a PC to be of any use ! In most cases these boxes are a cut down version of a
more conventional instrument without all the features of the full system. The
SonarMite extends this idea of a rugged design and minimalist interface to
produce a 'Blue Box' system where the user interface is provided by integrated
software running on a portable computer connected via a Bluetooth link. The use
of wireless technology enables the instrument to be waterproof and used in a
hostile environment while the more sensitive computer features can be located in
a more user friendly environment up to 50m away from the instrument.
SonarMite Measurements
The SonarMite instrument uses the same 'Smart' integrated transducer technology
used in the SonarLite system, in addition to highly reliable bottom tracking
algorithms using DSP techniques the system also outputs a quality value
associated with every depth measurement made. The popular SonarXP software
has been updated to SonarVista, in addition to the standard post-processing and
editing features found in the SonarLite software the program now includes
extended features to implement the additional measurements produced by the
SonarMite. Software for the 'front end'
of the SonarMite is available to run on a wide range of devices from Pocket PCs
through to the full range of desktop systems running the Windows operating
system.
The SonarLite uses active transducer technology manufactured exclusively for
use with the Ohmex Instruments range of survey quality equipment. All the signal
generation, data processing and filtering is performed digitally within the
transducer element, thus overcoming problems associated with old analogue
technology ...
| Low Signal Drift |
|
High immunity to temperature and environmental induced drift |
| Low EMC |
|
Transducer cable carries only power supply and data |
| Smart Filtering |
|
Smart filtering algorithms controlled by external processor |
| Low drop out |
|
Drop out rate ten times lower than analogue devices |
The Active Transducers are available in the standard 'Boat' shape transducer
using a 'Knock-off' body design patented by Airmar, this allows a transducer shoe
to be mounted on the rear transom of a boat alongside outboard motors, the
active transducer tracking and filtering algorithms are not effected by the
acoustic noise generated by the motor. The Airmar patent design allows the
transducer to kick its mounting if grounded and thus avoid serious damage.
New P66 Transducer
The
standard SonarLite 'Smart' transducer has been updated using the new
Airmar P66 shell and ceramic element.
This
design offers an improved 'slipstream' design together with a simple 'clip-on' fixing clamp enabling easier transducer
mounting/removal. The active processor has been updated to a flash memory
processor which enables the later reprogramming of the transducer to incorporate
new firmware features as they arrive. The SonarLite active transducer is a
specially designed Ohmex transducer with firmware designed for survey
applications to IMO standards, IT IS NOT THE SAME TRANSDUCER AS THE AIRMAR SMART
NMEA DEVICE although it uses the same shell.
Transducer Mounting
The SonarMite system is a portable hydrographic survey system so by
definition the boat used will be either a light portable boat or a vessel of
opportunity. The SonarMite transducer mounting is designed to fit on to a
vertical pole although the actual fitting will vary with the numerous different
types of vessel
The above illustration shows typical arrangements to mount the transducer in
a small inflatable craft, care should be taken to ensure that the mount is firm
enough for reliable readings but flexible enough to avoid damage if the
transducer collides with the bottom surface.
| 
