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Upgrading an FS-3DT to an Argos 500
The Argos 500 has the same mechanical footprint as our legacy FS-3DT product. It uses the same transducer array and stainless steel pressure case which means existing legacy FS-3DT users can easily upgrade their system to a Argos 500 for a fraction of the cost of a new Argos 500.
Does your bridge include 3D navigation sonar yet?
Forward-looking 3D navigation sonars have been available as an off-the-shelf tool for mariners since 2006. These products have a track record proving themselves as valuable navigation tools. These products have improved safety and operational efficiencies in a variety of marine environments. Historically, FLS technology has not been integrated into bridge systems and our products are often installed at the request of ship operators, captains and vessel owners as separate stand alone systems.
Best Practices for Navigating with 3D FLS
Our navigation sonars have been designed for ease of operation on a variety of vessels, from small yachts to large commercial vessels. We've spent countless hours refining our user interface designs and improving the signal processing that enables our sonars to look ahead at navigationally significant ranges. Part of the power of our systems is that we don't force the user to conform to one particular mindset: users can operate with color mapped to depth or color mapped to signal strength; the 3D sonar display can be set to a top down orthographic projection or a rotatable 3D perspective; we offer a profile display which slices a vertical strip through the 3D data. The list goes on and on. Along the way, we try to make these displays natural and lead the user to their ideal configuration. We know that everyone visualizes the world around them differently and we continually solicit input from our users on how make our user interfaces work best for them.
Cold Water Testing
When the temperatures start to drop well below freezing, most of the boat traffic on the Narragansett Bay disappears. Even if we would prefer to stay indoors by a fire or head for warmer waters, the FarSounder engineering team continues on water testing new sonar innovations. Recently, a few of the team boat tested FarSounder's latest 3D forward looking sonar equipment: our new bulkhead mount Power Module and our new flat faced Transducer Module option for the FarSounder-1000 and SPS systems. Though setting up the equipment in the morning was quite frigid, we had beautiful calm waters, interacted with a pod of porpoises and spent a little time watching harbor seals bask on the rocks. We thought we'd share a little bit of a "typical" work day on the water.
The 3D FLS Operator Experience: Making a Good Sonar Great
FarSounder's engineers spend a lot of their time working with customers to understand their navigation sonar needs. We strive to design our 3D FLS products with a good balance of performance metrics. However, our systems are more than just hardware. The software display is an important component too and as the saying goes, "a picture is worth a thousand words". That's why we've invested heavily in our operator interface, making a system that is easy to operate and easy to understand. Let's take a closer look at some of these features.
Comparing Forward Looking Sonars for Navigation
As with many technical products, understanding the differences between navigation sonar products sold by different vendors can be confusing. Much of the technical product literature can be confusing with different companies assigning different meanings to similar terms. At trade shows, we are often asked "What's the difference between Company X's product and yours?" or "Which is a better? FarSounder's sonars or Company B's sonars?". We don't like to presume we know every detail about every sonar on the market. Rather, we believe that once a customer understands which metrics they should be considering they can easily choose the best "look ahead sonar" for them. For our customers' class of ships, we're confident that they will choose a FarSounder. In this blog posting, we'll take a look at what we feel are the most important metrics you should use to compare forward looking sonars: Coverage Zone and Update Rate.
Chart Overlay Makes Collision Avoidance Easier
When looking at our software's 3D Sonar display it is sometimes difficult to correlate what we see on the screen to what we see (or don't see) out the bridge window. However, many users are used to correlating what they see on a radar display, especially if they have a radar overlay on top of electronic nautical charts. In our continuing efforts to improve user experience, we've recently added chart overlay of in-water sonar targets to our software. This enables users to more quickly and easily make the jump from what they see on the sonar's display to where potential navigation obstacles are located.
In-Water Target Stabilization: Showing Exactly What You Need to See
Due to natural variations in fluid characteristics (such as water temperature, salinity and density) and the presence of small in-water reflectors (such as moving currents, marine life, and bubbles), the underwater environment is acoustically dynamic and often unpredictable. That’s why we at FarSounder have committed ourselves to building incrementally smarter tools to help keep our customers on the edge of technology and as far from harm’s way as possible. As a result, we’re happy to give a sneak peek of our most intelligent underwater collision avoidance system yet, capable of stabilizing in-water targets detected by the sonar and providing you with the most accurate representation of the water in front of your vessel to date. Our new stabilization feature relies on tracking in-water targets detected across multiple transmit/receive cycles (i.e. “pings”). By grouping these detections and monitoring their movements over time, we can use that information to both filter out unreliable targets, and fill in gaps where we are confident targets should be seen.
Navigation Sonar for Exploration Yachts
As more and more yachts choose expedition style itineraries, the risk of collision with poorly charted obstacles or wrongly placed obstacles (due to GPS malfunctions) increases significantly. Groundings with large underwater structures such as rocks, reefs, sandbanks and shoals are unfortunately significant risks for the adventurer. Having a navigation sonar installed which is capable of detecting such hazards at long range is important in these scenarios. More importantly, the detection range of the installed sonar should be suitable for the vessel. In this blog posting, we discuss how to calculate a suitable detection range for your ship's obstacle avoidance sonar.
Explaining the Water Depth Limit and Other Unexpected Reflections
Not all forward looking sonars are created equal. Most only produce a view of a single 2 dimensional slice. Some use scanning technology to build an image from multiple pings. Few employ 3D technology. FarSounder sonars are the only look-ahead sonars which produce a true 3-dimensional image at navigationally significant ranges. They do this with a single ping enabling a fast update rate. Clearly, range is an important metric. However, one number alone cannot fully describe a sonar's range capabilities. A navigation sonar should specify its range not only in terms of maximum detection range for a given in-water target size, but also maximum range at which it can map the bottom. The first range metric is a number that is easy to specify given a target's reflectivity (e.g Target Strength) in a nominal marine environment. The second number is more difficult because it is not fixed. Rather, the bottom mapping range of a forward looking sonar is primarily a function of the water depth below the transducer. This blog posting explains what drives this limit and how these same concepts can explain other “unexpected” echo reflections.
Accidents and Groundings: A 21st Century Solution
Throughout the centuries that man has taken to the seas, ship (and crew/passenger) safety has been a critical concern. In both known and unknown waters, groundings and collisions have cost the lives of countless souls. These accidents have significant economic impacts with loss of ships and cargo and also environmental impacts due to oils spills and destruction of marine habitats.
Installing a Sonar on High Speed Vessels: Problems and Solutions
When considering one of our forward facing navigation or diver detection sonars, customers are often curious about the sonar's impact on the performance of their vessel. Most people are familiar with the general concepts of streamlining with reference to their car. Such effects when operating in air are described by the vehicle's aerodynamics. Similar effects as they relate to ships and boats traveling through water are called hydrodynamics. In this blog posting, we'll be discussing the general concepts that should be considered with evaluating the hydrodynamic impact of a particular installation.
Applications of Navigation Sonar Related to Ice
Navigation in and around ice is a very important topic for vessels destined for the arctic or antarctic waters. The rise of adventure cruising, scientific expeditions, and commercial shipping through these areas is keeping the topic in the forefront of many conversations. Ship operators in these areas are interested not only in detecting and avoiding icebergs but in some cases also knowing how close they can get to ice that is clearly visible above the water. Navigation in such areas is clearly reliant on seaman experience. Since the sinking of the RMS Titanic, engineers around the world have been working on ways to detect icebergs using various sonar technologies. In this blog post, we summarize how FarSounder's 3D sonars can be used to navigate in sea ice conditions and how our obstacle avoidance sonars can be installed on ice classed vessels.
Ground-Truth: Seeing What's There and Not What Isn't
The ultimate purpose of our 3D sonar products is very simple. We want to let users see dangers hidden under the water's surface. With our forward looking navigation sonars, this means seeing the obstacles that ship operators want to avoid. In terms of our ship protection systems, this also means seeing underwater intruder threats. This objective seems straight forward. However, the marine world is a complicated environment with lots of objects that can reflect sonar signals. Sometimes localized environmental conditions can even prevent sonar signals from propogating effectively. We want to make sure that the output from our sonars reflect (pun intended) the reality of what is under the water. This means that somehow we need to get an idea of what is actually there to determine if the outputs of our sonars are correct. This information is called "Ground Truth" and is the bain (or bounty) of every scientist and engineer who works on sensing technologies. It is impractical to cover all the procedures and techniques of effectively collecting ground truth data for a marine field-test in a blog posting. However, we can highlight a few interesting aspects of this never ending quest that makes working at FarSounder so interesting.
Marine Mammal Safety
Ship strike is a major cause of death for great whales (see footnotes 1,2,3). Our sonar can be used to help avoid these ship strikes, but we need to be sure we do so without introducing new problems. Motivation for FarSounder's technology began with an interest in helping vessels avoid hitting whales. We've done this by developing sonar products able to detect many types of whale sized objects. There are many types of sonars, and some are generally believed to be harmful. Our sonar products, however, are not in that class. Our systems operate at sound levels, frequencies, and durations that are safe for marine mammals and are environmentally benign.
DAMUS: FarSounder's Sonar Performance Prediction Tool
Given an echo returned from an environment within sonar's field of view, the ultimate goal of a FarSounder product is to decide whether the echo corresponds to a true target in the 3D space. The target could be the sea floor, an in-water obstacles, marine life, a diver, etc. This detection problem is fundamental to all of our products irrespective of their purpose: navigation or threat detection. FarSounder engineers have developed several tools that make their life easier when they need to unravel the complexity of underwater detection problems. One of the tools central to research and development at FarSounder is our sonar performance prediction tool, code named: DAMUS.
Doing it for Science: 3D Forward Looking Sonar for Research Vessels
As FarSounder's customer base grows, we are continually learning about new applications for our navigation sonar products. As a marine company focused on engineering unique technologies, we obviously have an interest in the greater world of marine science. Though we do not study the occean per se, our products can be used as tools to help others study the ocean. This blog entry is intended to highlight some of the applications of our 3D navigation sonars for Research Vessels. With these products, we hope not only to provide safer navigation to users but also add some compelling reasons to add our tool to the researcher's arsenal of tools.
Protocol Buffers and FarSounder
As technical people interested in the "magic" behind the scenes, FarSounder's engineers often are curious about technology behind many of the products we use. Sometimes, some of those companies share a little bit about the choices and technologies that went into their products. We thought we'd do the same and discuss some of FarSounder's behind the scenes technology as it relates to our recently open sourced protobuf-matlab project.
Installing New Sonar on Old Vessels: Breaking Down the Refit Process
For an end user new to FarSounder sonars, the idea of retrofitting a sonar into an existing hull can seem daunting. However, once the details are examined, the process is relatively straight forward. Approximately 50% of our customer installations are refits to older hulls. Even some of the New Builds that have our sonars have approached integration of our systems as a "refit" when our products have been added to the ship's specifications late in the build process. When beginning to consider one of our 3-dimensional forward looking navigation or diver detection sonar systems, potential customers are often concerned with the installation design process and any potential hydrodynamic impact on the hull. These are important questions to which we believe there are some simple answers. The purpose of this blog posting is to explain the basics of refitting a vessel for our 3-dimensional forward looking navigation and diver detection sonar systems.
Advantages of Array Processing Over Scanning Sonar
When considering a sonar product for use in navigation, it is important to consider a number of parameters and system characteristics. Obviously, the ability to look ahead is important. However, "where", "how", and "when" the sonar looks ahead are characteristics that will determine if a particular sonar is suitable for navigation and practical obstacle avoidance. A sonar's overall system design impacts these characteristics significantly. Scanning sonars are one of the most common system designs for advanced sonar solutions as they are relatively inexpensive and relatively small. This makes them a good solution for many applications. Unfortunately, real-time navigation is not one of them. This blog post illustrates the advantage of phased array processing sonars over scanning sonars for navigation applications.