We are very excited about the overwhelmingly positive response to our Navimate™ product announcement at the DEMA show.

Here is some additional information and answers to common questions:

Please visit our website at navimate.shbinstruments.com. We will be adding this document as well as further information to the site in coming days.

Because GPS signals are not directly receivable under water, Navimate™ functions through use of a small unit that is most commonly hung from a dive boat or buoy (the “GPS gateway”). The GPS gateway has a floating radio antenna in order to determine its exact location, and communicates with the wrist units via its underwater transducer portion, using acoustic signals. As a result of this communication, the wrist units know their range and bearing from the GPS gateway, as well as the exact position of the gateway. This allows the wrist units to calculate their own absolute position, independent of the position or motion of the GPS gateway. The gateway or the boat to which it may be attached is free to drift without affecting the position displayed by Navimate™. The position is displayed on the Navimate™ screen both as latitude and longitude values as well as a “dot”.

Other Navimate™ units within about 100 yards (90 meters) are broadcasting their position, and will be plotted as small diver icons on each other’s screens. These icons can be tagged with identifying information, as well as the diver’s depth and velocity, if desired. The location of the dive boat is also shown, as well as a compass rose with the diver’s current heading, and the heading back to the dive boat. The Navimate™ display can be zoomed in and out to change the scale of the area displayed on the screen as desired by the diver.

The acoustic communication between the Navimate™ units and the GPS gateway are relatively low-power, wideband digital signals that will have no impact on marine life – they will only be heard as a low level noise-like sound.

The local communication between the Navimate™ devices allows for features such as an “SOS” alert to the diver’s buddies, or even the sending of messages between divers.

In order to get back to the boat the diver need only turn until his indicated heading aligns with the heading back to the boat, and swim in that direction. However, this system offers much more functionality than previous “how do I get back to the boat” beacon systems. With one button press the diver can mark interesting or important locations (“waypoints”) in order to return to their exact positions on any future dive, as well as record a “track” of the path of their dive, including depth information. These waypoints and tracks can be uploaded to a computer at any time, and downloaded back to Navimate for use in the future.

The contour maps of underwater terrain are a “bonus” to allow divers to see local features, and the unit loses no functionality if maps are not currently available for the dive site. We support a number of common map formats, which allows downloading of additional maps from a computer as they become available. Navimate™ also has the ability to display additional information for the dive site, such as local fish species, or interesting aspects of the site. The firmware (resident software) in Navimate will also be field downloadable, allowing units to be upgraded to support new features by downloads from our website.

The depth limit of the initial device will be determined only by pressure limits, and will be 250 feet (75 meters) for initial production units.

Maximum operating range from the boat to the wrist units is ½-1 mile (.8-1.6 kilometers), depending on ocean conditions (highly turbulent water, kelp, etc.). Accuracy is 20-40 feet (6-12 meters) at the maximum range, and 10 feet (3 meters)at distances of ¼ mile (400 meters) or less (limited by GPS accuracy). There must be a reasonably good line of sight between the Navimate™ wrist unit and the GPS gateway. The signal will be “diffracted” around smaller obstacles such as a pile of rocks, but can be blocked by larger objects, such as wrecks. In these circumstances a second GPS gateway can be deployed from a buoy, to insure complete coverage of the area.

We have been extensively testing prototype hardware and software and are beginning production of units for retail sales. Navimate™ will be available for sale in May or June of 2010. The wrist unit will retail for US$700, and the GPS gateway for US$300. We will be offering the GPS gateway free to shops, clubs or other organizations that purchase a minimum number of the wrist units and will also be placing the gateways on selected dive boats at no cost. Instructor discounts for Navimate™ will also be available.

Soon after the initial release of Navimate™ we will be offering a “no display” unit at reduced price, which will be designed for attaching to the tanks of students with an instructor or divers being led by a divemaster. The instructor or divemaster will then be able to keep track of the location of the other divers in his or her group, but those divers will not be burdened with the distraction (or the cost) of a wrist-mounted unit.

The next product (now being designed) will answer the many requests to be able to keep track of diver locations from the dive boat. The Navimate units are broadcasting their GPS positions on a low-power acoustic beacon, allowing us to map the locations of dive buddies within a range of about 100 yards (90 meters). In order to be able to keep track of diver locations at the full ½-1 mile (.8-1.6 kilometers) operating range of Navimate, we will offer a more sensitive acoustic receiver that can be used from the boat and connected to a laptop or other shipboard display.

Finally, the obvious follow-on product integrates a dive computer with Navimate™. We have plans to build such a unit, but based on our conversations with several computer manufacturers at DEMA, this may be done as a joint product development with an existing computer manufacturer.

For applications such as submersible vehicles, we will manufacture a ruggedized OEM version of Navimate™, able to operate at increased depth, and including external connections for synchronization with devices such as video cameras, as well as allowing for remote connection of display panels.

Future enhancements include increasing the accuracy of Navimate™ to three feet or less by using a more sophisticated GPS system at the gateway.

We welcome feedback and suggestions for enhancement of Navimate™’s functionality. Please email us at navimate@shbinstruments.com