seaView Software V3 provides a cutting-edge user interface for the setup and operation of Impact Subsea sensors.

Transcript

Hi! I’m Ben and in this video we’ll be looking at the ISA500 application in seaView software V3.

When you first run seaView software you’ll be presented with this window here.  On the left hand side. You have a list of applications within seaView software. On the right hand side you have a list of all communication ports and network connections on your pc. When you first run seaView software it will automatically scan all communication ports at every known baud rate. It will then automatically detect any sensors connected to your computer.

In this example two sensors have been detected, one is the ISS360 Sonar and the other is the ISA500 Altimeter, as shown in the center of the screen. If you look at the icon for the ISA500 Altimeter, you’ll find you’re given a little bit more information such as the serial number of the sensor, the firmware version and also how it’s connected to the software. In this particular example we can see it’s connected via COM Port 5 at a baud rate of 115,200. If you double click on the ISA500 icon you’ll be taken into the ISA500 application.

seaView Software Application main screen

Now in the application, the top left hand corner shows the distance reading being reported by the ISA500. Every time the sensor pings you will see a green flash of this light here and a distance reading reported. Below the distance reading you also get an energy and correlation value. Also reported is the temperature of the ISA500 internal electronics and if you have an ISA500 with integrated Heading, Pitch and Roll, you’ll also get Heading, Pitch and Roll readings with a little 3D model of the sensor to show you how it’s orientated at any one time.   

Acoustics settings

In the middle of the screen you’ve got a graph showing distance measurements over time. The left hand side of the screen you have a number of icons. Now if we start with the top icon, this is the ISA500 settings, so if you enter the settings you’ll be presented with a window like this. The first settings window is all to do with the ISA500 Acoustics.  

The ISA500 is a highly configurable altimeter. You can configure many parameters; for example you can change the detection mode you can operate in first detect, strongest or seabed tracking. First detection mode is ideal if you’re working in a confined space where there’s a lot of multi-path, multi-echo capability such as inside a tank. Strongest echo is better for open water activity and if you’re wanting to track the seabed then there’s a seabed tracking option as well.

You can also enable and disable tilt correction, so if you have an ISA500 with integrated AHRS, enabling tilt correction will automatically convert slant ranges into actual altitude so it’ll correct for pitch and roll of your vehicle and give you a more stable altitude reading. You can disable this if you wish and just have pure range readings from the sensor.

You can then configure minimum and maximum ranges, so for your minimum range anything below the set value will never be detected by the ISA500 and your maximum range anything above that value will never be detected by the ISA500 so you can basically gate the ranges that you’re wanting the sensor to look over.  

You can also set the frequency. The ISA500 is a broadband altimeter so you can run it anywhere from 400 to 600kHz. You can set the speed of sound to give you an accurate distance reading, you can set the pulse length and the pulse amplitude. You can also put in any distance offsets as required. Moving on to the next settings window the analogue output.

Analogue output

The ISA500 can provide you a serial ASCII output but it can also provide you a scaled output and it can provide a scaled current or it can provide a scaled voltage and you can set up the scaling. So you can set up the start and stop voltages and your minimum and maximum ranges to scale that over.

Echoes

The next setting option is your multiecho setup and this is the number of echoes to be reported on from a single ping. Most applications the ISA500 is used just to give a single range reading but it can also give you multiple range readings from a single ping and you can set how many range readings you want the sensor to report on.

Connection

The next option is your connection so in this window here you can select the serial mode which  can be RS232, RS485 or RS485 terminated. You can also set the required baud rate together with the word length, parity and the number of stop bits required.

Output string

The next option is the output string. This is the output string for the distance reading. There’s a number of pre-configured strings and all of which are detailed in the ISA500 manual so you’ve got a number of Impact Subsea strings and you have a number of third-party strings to allow the ISA500 to emulate other altimeters in the market. If the particular string you require is not there you also have the custom button which allows you to create your own ASCII output string in the exact format which you require.

You can also set up in this window what the ISA500 should do if no returns are received whether it outputs a zero reading or a maximum reading and you can also tell it how many times you want it to ping an output to reading anywhere from well a fraction of a second up to up to 100Hz.

You can also set up the interrogation method so if you want to interrogate the ISA500 and command it to ping you can enable that and also set the parameter for it to respond to. You can also select interrogate via TTL if you want to trigger it via TTL and you can select whether it’s the falling edge or the rising edge of the TTL pulse which it triggers on.

AHRS settings

Then if you have an ISA500 which has integrated AHRS you’ll have the AHRS settings option. In here you can configure everything to do with the Heading Pitch and Roll. To start off with you can select the orientation, by default it’s assumed that the ISA500 has the connector pointing upwards and the transducer pointing downwards, however you can change it to be inverted or pitched over or rolled over. And these just set the reference point for your your Pitch, Roll and Heading to make sure you get accurate readings.  

Once installed on the vehicle if there’s any inaccuracies and how it’s been installed you can apply minor offsets to the heading pitch and roll. You can also apply a magnetic declination offset enable inertial mode, calibrate the magnetometers and set up your turns counter for the sensor as well.

AHRS output string

The last option to look at here is your AHRS output so this configures the ASCII output string for the heading pitch and roll side of things. And as before the number of Impact Subsea strings and there’s a number of industry standard strings as well. All of which are documented in the ISA500 manual and again as before if there’s a string you require which isn’t there or you want a slightly different string you have the custom option to go in edit a string or create an entirely new string to meet exactly what you require.

Like the altitude or range output you can select how many times per second the string is output. You can also enable interrogation and set up the parameter for the ISA500 to respond to and you can also have the output output on a TTL interrogation as well so that’s all the core ISA500 settings so if we return to the main screen.

If we look at the left hand side again there’s a ping button so you can manually trigger a ping from the sensor and there’s also a ping rate and this sets the ping rate of the sensor when it’s connected to the seaview software so it’s currently set to 1Hz.

We can increase it to 5Hz or 10Hz or we can set the sensor to run at maximum rate. If we set to maximum it’ll basically ping as fast as it can given your minimum maximum range setting. And as we change the ping rate you can see that green light flashes at the designated rate and that basically flashes once per ping on the sensor.

Record log file

At any time you can enable a log file by clicking here and it will record all the ISA500 readings to a log file and time stamp them. You can clear the graph data here if you want to start afresh. You’ve got display options so you can set exactly which parameters you want to be showing on screen. For example you could turn off the temperature we turn off the heading pitch and roll so you’ve just got altitude in the little 3D model for the ISA500, or you can enable all those back on again. Turn on the turns counter, so it will show you the number of turns the ISA500 has made.

Multi-echo output

And the last item I’ll show you here is the multi-echo output capability. If you click show multi-echo it’ll bring up another graph at the bottom of the screen. You can click and make this graph a bit larger and this graph will essentially show you every single return that ISA500 sees from a single pulse being sent out. It gives you a good appreciation of exactly the acoustic environment in which ISA500 finds itself. Or if you want to make multiple measurements to different targets that fall within the six degree conical beam from the ISA500, this is a good way to do it.

Multi-echo output

And the last item I’ll show you here is the multi-echo output capability. If you click show multi-echo it’ll bring up another graph at the bottom of the screen. You can click and make this graph a bit larger and this graph will essentially show you every single return that ISA500 sees from a single pulse being sent out. It gives you a good appreciation of exactly the acoustic environment in which ISA500 finds itself. Or if you want to make multiple measurements to different targets that fall within the six degree conical beam from the ISA500, this is a good way to do it.

ECHOGRAM

Since the above video was created, a new feature was added to seaView. For ISA500 sensors with ECHOGRAM enabled, the ECHOGRAM graph can be shown.

This provides full sonar backscatter data (up to 2,000 samples per ping). A full technical overview of ECHOGRAM can be found here.

Graph options

One other item to consider, on the right hand side of the screen we have a graph options button and this allows you to edit the graph display so you can turn off the fill and you can have it draw points for every ping, can turn off draw lines you can basically alter things to get the exact graph that you want to have on screen.

That’s the ISA500 application in seaView Software V3, if you have any questions regarding this please do not hesitate to contact us at support@impactsubsea.co.uk

Take a look at the ISA500 Product Page: ISA500 Altimeter

Learn more about how our altimeter works in this in-depth technical guide

Watch seaView Software overviews on our other sensors: YouTube playlist

The ISA200 & ISA500 are widely used as underwater Altimeters on Remotely Operated and Autonomous Underwater Vehicles.  The sensors are also used as high accuracy underwater ranging devices, providing distance measurement to any target aimed at.

Measurement Range:

A critical consideration when choosing an underwater Altimeter is how far away will it be able to detect the seabed (or other target) from.

The use of a digital correlation echo detection technique combined with a highly sensitive composite transducer enable the ISA500 to provide market leading range performance from a 500kHz frequency Altimeter.

The ISA500 is characterised as having a range capability in excess of 120 meters / 393 feet.  The ISA200 has a range in excess of 250 meters / 820 feet.

Both sensors operate on sonar technology – they transmit a pulse of sound and time how long it takes for the sound to return.  Based on the time taken, it calculates the distance travelled by the sound and derives the range to target.

The overall range capability will largely depend on the acoustic reflectivity of the item it is pointed at.  For example, if pointed at a seabed with a large amount of marine growth on the surface,  a reasonable proportion of the pulse of sound will be absorbed.  In which case a range of 80 meters/ 262 feet or less may be achievable with the ISA500. On the other hand, if the seabed has a strong reflector, such as solid rock, ranges in excess of 175 meters / 575 feet can be achieved with the ISA500.

The sensitivity of the ISA200 and ISA500 ensures that the longest range possible for the environment it is operating in can be achieved. 

Measurement Accuracy:

For many applications, accuracy and repeatability of the distance measurement are highly critical.

As mentioned previously, the ISA200 & ISA500 use an advanced digital correlation technique to detect the reflected pulse of sound.  This digital correlation is run 2,000,000 times per second.  This gives the ISA200 & ISA500 an accuracy level of 0.7mm which is then rounded up to the nearest 1mm.

This allows the ISA200 & ISA500 to provide 1mm accuracy and repeatability in range measurements.  This introduces the sensor to applications where previously only technologies such as a laser-based measurement systems would suffice.

A critical point to appreciate is that the ISA200/ISA500 offers 1mm accuracy as well as resolution.

When defining the capability of an Altimeter, it is important to recognise the difference between resolution and accuracy. A number of alternative Altimeters are quoted as having ‘1mm resolution’ which in itself is a relatively meaningless statement unless the Altimeter also has 1mm accuracy.  Otherwise, the sensor is simply providing centimetre level of accuracy to 1mm precision.

When choosing an Altimeter, one should always check what the measurement accuracy is – not just the resolution.

The below is a short example of the ISA500 achieving 1mm accuracy in distance measurement over a 1 meter range: 

Measurement Quality:

A key question with every reading from an underwater Altimeter is: how trustworthy is the reading which has been made?

In addition to the distance measurement value, a number of serial output strings from the ISA200/ISA500 also report back the energy level of the echo and a correlation factor.

The energy level ranges from 0 to 1, where 1 represents full saturation of the ISA200/ISA500 receiver. An energy level of 0.707 (square root of 2) is the theoretical perfect level as it represents the energy of a pure sine wave with an amplitude utilising the maximum dynamic range of the ISA200/ISA500.

The correlation factor ranges from 0 to 1, which represents a quality factor of the returned echo. A value of 1 would represent a return echo of perfection with negligible noise and distortion.  

The correlation value alone can be used as a trust factor where low values such as 0.3 would indicate that a reading is likely incorrect.  In practice, ISA200/ISA500 sensors are pre-set to ignore all returning echoes with a correlation level below 0.5.  This ensures every reading produced by the sensor is of a high quality level. 

A more detailed picture can be built by combining this information with the energy level as shown in the table:

With energy and correlation values, the quality of the distance reading provided by the ISA200/ISA500 is always clear. 

Acoustic Bandwidth:

The ISA500 can be operated at any frequency from 400 to 600kHz.  The performance across this bandwidth is relatively uniform, with a slight increase in performance at the 500kHz point.

The available bandwidth allows for multiple ISA500 sensors to be operated in close proximity, all at slightly offset operational frequencies.  This ensures that there is no interference between sensors.

The available bandwidth also allows for the sensor to be adjusted to another frequency to move it out of band of other acoustic devices in operation (Sonars, Profilers, DVLs etc).  Thus, ensuring there is no interference with third party systems.

ISA200/ISA500 Altimeter Interfacing:

The ISA200/ISA500 comes as standard with both RS232 and RS485 serial interfaces integrated into the sensor. 

The sensor can run directly into Impact Subsea’s seaView software or it can output any number of ASCII strings for integration into third party systems.  This includes proprietary Impact Subsea strings, but also the ability to emulate any other underwater Altimeter – making the ISA200/ISA500 a very simple sensor to retrofit to existing systems.

In addition, the ISA200/ISA500 has a voltage and current analogue output as standard which can be scaled across a user defined distance and output voltage/current.

ISA200 & ISA500 Altimeter Software Configuration:

One of the key benefits of the ISA200/ISA500 Altimeter is that all settings are entirely software configurable.  There is never a requirement to open the sensor – all settings can be adjusted using the freely available seaView software.

From an acoustic perspective: the detection mode, minimum and maximum ranges, pulse length, operational frequency etc., can all be altered to allow the ISA200/ISA500 to achieve the best performance possible in the application to hand.

The communications mode, output strings, update rate etc., can all also be configured using the seaView software and then saved to the sensors firmware.

The below video provides an overview of the ISA200/ISA500 application showing where all the core elements of the user interface are and highlights the settings available on the ISA200/ISA500 sensor itself.

Multi-Echo:

Most underwater Altimeters will output a single distance reading.  The ISA200/ISA500 can do this, however it also has the option to output the distance reading of every echo that is returned to the sensor.  This allows multiple targets to be tracked within the acoustic beamwidth of a single ISA200/ISA500.

Detection Mode:

The ISA200/ISA500 Altimeter has several detection modes available to select which returning echo is used when calculating the distance measurement.  

‘First’ detection mode will use the very first echo to be returned.  This mode is ideal for use in high multi-path environments such as water tanks.  Once the first echo has been returned, all other echoes will be ignored. 

‘Strongest’ detection mode will use the strongest (highest amplitude) echo returned.  In this mode smaller echoes will be ignored and only the largest reflected echo from the seabed used.  This provides very stable range measurements, especially helpful in applications with a large amount of suspended sediment (such as trenching). 

‘Seabed Tracking’ will use an algorithm to determine where the seabed is and will operate to track this range, ignoring any obviously incorrect readings. 

Echogram:

Optionally available on the ISA200/ISA500 is ECHOGRAM. This new feature adds a full backscatter capability to the ISa200/ISA500, enabling the underwater Altimeter to be upgraded to have a full single beam imaging sonar capability.

Underwater Altimeters typically provide only a single range reading per ping. However, with the addition of ECHOGRAM, the water column and seabed can be fully visualized, allowing for visual identification of targets. This provides up to 2,000 samples per ping, with each sample representing the correlation level of acoustic signal return at its particular point in the range.

Attitude & Heading Reference System:

The ISA200/ISA500 is optionally available with an in-built Attitude and Heading Reference System (AHRS).  This provides Heading, Pitch and Roll as a secondary output.

Aside from a useful additional measurement parameter, the AHRS can also be used internally within the ISA200/ISA500 to correct for Pitch and Roll.

Usually if the vehicle or asset which the Altimeter is mounted pitches or rolls, this causes the Altimeter to measure slant ranges and will make the Altitude reading rise up and down, despite there being no actual change in Altitude.  The AHRS can be used to correct for the pitch/roll by changing the slant range measurement into actual altitude through basic trigonometry.

This ability can be turned on and off in the ISA200/ISA500 settings.

ISA200 Altimeter – Physical Configuration:

Detailed chart of options available when purchasing an underwater altimeter

ISA500 Altimeter – Physical Configuration:

To ensure the ISA200/ISA500 is simple to integrate into any application, a variety of physical configurations exist. The ISA200/ISA500 is available in Titanium or Acetal materials, both used due to their longevity. 

The ISA200/ISA500 is also available in a forward looking or right angled housing and to a variety of depth ratings from 1,000 meters to 6,000 meters.  The ISA500 is also available to a depth rating of 11,000 meters. 

Alternative OEM options are also available for direct integration into your own housing if required.

For example, the Acetal Right Angled ISA500 sensors are a popular choice to use in towed Magnetometers.  OEM options are useful for small compact AUVs. The Titanium Forward Looking ISA200/ISA500 sensors are a popular choice for medium and workclass remotely operated vehicles. 

Robustness: 

The ISA200/ISA500 Altimeter has been designed and built with the highest levels of longevity and robustness in mind.

As already highlighted, the housing materials used are either Acetal or Titanium, chosen due to their longevity and strength.

The electronics are of commercial grade and are of single board design.  All components are low mass to ensure excellent shock and vibration performance.  No screws are used within the design, with a snap and lock together methodology being used to ensure no parts can come loose over time.  

The ISA200/ISA500 sensor has undergone vigorous environmental testing. This includes vibration, shock and thermal testing to meet the stringent requirements of API 17F qualification.

Overall:

The ISA200/ISA500 Altimeter/Echosounder/Ranger provides a long-range underwater measurement capability combined with a high level of accuracy.  

The ability to configure all aspects of the sensor via software enables the sensor to be easily tuned to suit the application at hand.

A robust design ensures that the ISA200/ISA500 is suitable for the most challenging of environments. 

If you would like to discuss the ISA2000 or ISA500 in more detail, and how it can be used in your underwater application, please drop us an email at support@impactsubsea.co.uk

Or alternatively, call us on +44 1224 460 850

The latest ISA200 and ISA500 Altimeter datasheet, manual, 3D models and further technical information can be found on the product page

Watch and learn more about the ISA200 & ISA500 Altimeter: YouTube playlist

Transcript – ISA200 & ISA500 Accuracy & Performance

Welcome to a deep dive into, well, the truly cutting edge world of advanced underwater sensing.

Today we’re putting the ISA200 and ISA500 Altimeters from Impact Subsea under the microscope. Yeah, these aren’t just any sensors. No, they promise really unparalleled perception beneath the waves. And we’re here to unpack exactly how they do it.

Our mission really is to show you why these devices are such a game changer. We’re talking precision, reliability in the toughest environments, too. Exactly. in the most unforgiving parts of the ocean. We’re looking at tech that tackles the real challenges of working deep underwater, bringing a whole new level of clarity.

Okay, so let’s dive into their capability first. These are sonar based devices, right? Using sound to measure distance. That’s right. And the ISA200, it can range over 250 m. That’s what about 820 ft. Yeah. Impressive range. And the ISA500 goes beyond 120 m. So 393 ft.

But what really gets me is how the environment itself changes that range. It’s not fixed. It’s true. And it makes sense when you think about it. What the sonar is actually pinging off makes a huge difference. Like what? Well, think about a solid reflective target like rock. That can give you a much greater distance reading, sometimes over 175m for the ISA500. Okay. But if you’re aiming at something softer, maybe marine growth or sediment plumes, much fuzzier target. Exactly, that range might drop to 80m maybe even less. The clever part here is how these altimeters actually optimize their sensitivity. Ah they adjust. They adjust. Yeah. To give you the best possible reading whatever conditions you’re facing down there. That’s incredible.

But how do they maintain any kind of precision with all that variability? I mean this is where it gets truly mind-blowing for me. These sensors boast an astounding 1mm accuracy and repeatability. 1 millimeter. That’s tiny. It is barely the thickness of a credit card. like you said. So, how do they achieve that kind of pinpoint precision through water which can be so murky and unpredictable? It’s a fantastic question and it’s down to a really advanced digital correlation technique. Imagine trying to pick out a tiny clear radio signal in a storm of static. This technique is like a super advanced filter, right? It rapidly sifts through literally millions of echoes, actually two million times per second to find the true signal, ignoring the noise. 2 million times a second. Wow. Yeah.

And this isn’t just about resolution, which lots of sensors talk about. What’s the difference there? Well, resolution just tells you the smallest change it can detect. Accuracy tells you how close that measurement is to the actual real world distance. I see. So, it’s not just detecting tiny changes. It’s knowing those changes are correct. Precisely. The ISA200 and ISA500 deliver both. And that’s absolutely critical for jobs that used to need much more complex, often fragile laser systems. Like what kind of jobs? Things like detailed pipeline surveys or maybe precisely docking an ROV with some subsea equipment. Tasks where being off by even a little bit matters a lot. This is a huge leap in underwater reliability.

Okay, so the sensor is incredibly precise, but how do you know the data itself is trustworthy, especially if the water is murky or full of particles? All right, good point. That’s where their correlation factor comes in. Think of it like a built-in quality check, a confidence score for each echo. A confidence score. Yeah. If the sensor isn’t at least say 50% confident that an echo is a genuine reflection, if it’s below a 0.5 correlation, it just ignores it. So, it filters out the dodgy readings automatically. Exactly. You’re only getting data that the system itself considers reliable. Every reading you get is one you can trust. That’s brilliant. Intelligent data right out of the box.

But, how adaptable are they? If you’re in a busy subsea area with other acoustic gear, maybe. Yeah, that’s key. Their adaptability is fantastic. The ISA500, for instance, lets you actually adjust its operating frequency. Oh, okay. Anywhere between 400 and 600 kHz. So, you can actively steer clear of interference from other sensors. Smart.

And what’s more, pretty much all their settings are fully software configurable through seaView. You can tweak detection modes, maybe use strongest detection if you’re navigating through suspended sediment. Or you can even use a multi-echo capability for tracking several targets at once. It’s like having a well Swiss Army knife for underwater sensing.

And it gets even more visual, doesn’t it? There’s an optional ECHOGRAM feature. That’s right. That essentially turns them into single beam imaging sonars. Imaging sonars. Wow. Yeah. It visualizes the whole water column and the seabed below. You get up to 2,000 data samples per ping, giving you a real-time picture. Really helps with visual ID of what’s down there. Okay, that’s impressive.

What about vehicle movement? If the ROV or AUV is tilted, yes. Slant range. A standard altimeter might just give you the distance along that tilted path, which isn’t your actual height off the bottom. Exactly. But with the optional built-in AHRS, that’s an attitude and heading reference system, like in drones. Sort of. Yeah. It constantly knows the vehicle’s pitch and roll. It does the trigonometry internally to correct that slant range and give you the true vertical altitude. So you always know your actual height regardless of tilt precisely. Very clever.

So okay, incredible intelligence, pinpoint precision, but underwater gear takes a beating. How tough are these things? How are they engineered for endurance? Well, they’re built for it. Seriously tough. Construction is from titanium or acetal. Very durable materials. And the depth ratings, the ISA500 is rated up to an incredible 11,000m. 11,000m. That’s deeper than Everest is tall. That’s Mariana Trench territory. Literally capable of reaching the deepest parts of our oceans.

Wow. And it’s not just about pressure. They’re rigorously tested to API 17F standards for shock and vibration, which means it means they’re basically put through hell in testing. Extreme shocks, crazy vibrations, way beyond normal operational use. So you can absolutely trust they won’t fail when it matters most thousands of meters down.

Okay, so we’ve really covered a lot. Incredible range, that pinpoint 1 millimeter accuracy, intelligent data quality, all wrapped up in a design that’s robust and amazingly adaptable. Yeah, what stands out, I think, is just the meticulous engineering. It brings real insight, genuine reliability to the underwater world. It transforms what’s actually possible in these really challenging environments.

So wrapping this up, what does this all mean for you? When every single millimeter counts, how might these kinds of precise, reliable eyes continue to shape how we understand and how we interact with our planet’s last unexplored frontiers? What new possibilities open up down there?

ISA500 – ECHOGRAM Transcript

Hi I’m Ben, Managing Director of Impact Subsea and today we’re looking at the ISA500 – ECHOGRAM feature within the ISA500.

Now when you run seaView V3, you’ll be presented with a screen very similar to this one and when you connect your ISA500 to seaView it’ll show up as a tile here. Double clicking on the ISA500 will bring up the ISA500 application.

Within the ISA500 application you’ve got your distance reading, the top left hand corner you’ve got the temperature of the sensor itself, inside the sensor. If you have AHRS enabled in the ISA500 you’ll also have heading, pitch and roll and a 3D model shown on screen. These values will update as the ISA500 is moved so if we move the ISA500 in real time you can see the heading, pitch and roll change along with the 3D model. We also have a turns counter on screen which will count the number of turns of the ISA500 about a specified axis. Below that we have a a graph of distance over time on the screen.

ISA500 – ECHOGRAM Capability

For those with an ISA500 – ECHOGRAM capability; if you navigate to the left hand side of the screen, click on ‘Show Echogram’ if you click on ‘Show Echogram’ it’ll bring up the ISA500 – ECHOGRAM graph and we can adjust the value of that graph.

I’ll just adjust it so its full size on screen just now and what we’re seeing being presented on screen is a graph slowly building up. Now at the moment the ISA500 is set to ping at just 1 Herz so doing one ping per second so the graph is quite slowly building up.

Ping Rate

We can adjust the ping rate of the ISA500. On the left hand side here there’s a ping interval button. If you click that you can select how many times a second the ISA500 should ping. You can select anywhere from 1 Herz to 10 Hertz & maximum. The maximum rate you can ping at will be dependent on the range at which the ISA500 is set over and also the bandwidth of your serial communications. For now we’ll set it to maximum so we’ll get it pinging as quickly as we can so we can see a graph building up a lot quicker on screen just now.

Demonstration in Test Tank

At the moment the ISA500 is just in our test tank behind me here and it’s sitting statically at a set height so we’re just getting quite a a flat line. If we take the ISA500 and move it in the water a little bit and lower it down you can see the the graph representing the lowering of the ISA500, if we rise it back up again you can see the is ISA500 coming back up on screen there. You move it up and down you’ll get a nice sinusoidal graph showing there and again if you just tie it off so it’s sitting there statically you get a flat line again.

Graph Display

On the left hand side you can adjust the the colour of the ISA500 – ECHOGRAM data so we’re using the multicoloured chart just now but you can also use a gold palette or a more blue palette. I’ll leave it on the multicoloured chart for the rest of the demo.

On that graph there you can also adjust the red box, lower part of the colour chart. That is a threshold so if you bring that up it’ll remove the weaker returns and only show you the stronger returns on screen. You bring it down, it’ll show you more and bring it right down to the bottom, it’ll show you every single return there. You can also move the tab at the top this acts as a compression on the color chart and it’ll increase the contrast on screen so you bring that down quite a lot, get a higher contrast image.

Samples Per Ping

On the right hand side of the software application you’ll find an ‘Echogram options’ button. If you click this it’ll bring up a few other options you can tweak. One is the number of lines on the X axis. If this is set to ‘Auto’ it’ll lock the number of lines in the X axis. The number of pixels on screen, in this case 1,492.

The ISA500 has the capability of outputting up to 2,000 samples per ping. That’s the the maximum number you can show on screen at one time. You can disable the auto feature and you can put in a set number of lines or samples to be returned. We can set that to any value from 0 to 2,000 that we want or we put it back to ‘Auto’ it’ll just lock it to the pixels on screen again.

ISA500 – ECHOGRAM Options

There’s a gain here which is purely a software gain so this will adjust the data which is on screen so you may want to tweak this. Turn it up if you’re looking for weaker echoes so you can see them more clearly.

You can also invert the Y axis you can blank the minimum range. If that’s turned off you’ll see the transmission burst of acoustic energy in the ISA500. You turn that on, it just blanks that out so you don’t need to see it.

If smoothing is turned on it’ll give a little bit of interpolation between each ping and just give the data a nicer smoother look. You can also turn on and off the the colour palette if you don’t want to have that showing on the screen.

Demonstration in Test Tank

I’ll just give a quick demo, so if we move it up to the highest point you can see the graph there showing a high reading, if we slowly lower it down, you can see that going down there. You can see most of the turns are quite red because we’re getting quite a high energy return off the base of our tank.

If you’re doing this in open water, if you had a stony kind of seabed, you’ll get quite high energy returns. If it’s sand, slightly less energy, if it’s covered in marine growth gets less energy still.

The benefit of ISA500 – ECHOGRAM is you’ll be able to see the marine growth sitting on top of the seabed.

If you wanted a full overview of the ISA500 application, including all ISA500 acoustic settings, check out our ISA500 overview video.

Thank you.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

► LETS CONNECT: ◄

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

2D Magnetic Calibration

This video shows how to conduct a 2D magnetic heading calibration on Impact Subsea sensors with AHRS.

This is a useful calibration procedure for the ISA500, ISD4000 or ISM3D when mounted to a Work Class ROV or other large underwater item where the full 3D calibration is unable to be performed.

The 2D calibration allows the heading to be calibrated by simply rotating the ROV 360 degrees.

Download seaView software here: https://www.impactsubsea.co.uk/seaview-v3/

You can also drop us an email at support@impactsubsea.co.uk and we’ll answer any technical questions that you have.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

► LETS CONNECT: ◄

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT

Inversion Reset V3 – Transcript

Hi, I’m Ben Grant, Managing Director of Impact Subsea.

In this video, we’re going to show you how to set your Impact Subsea sensor to a known communications protocol and baud rate. In this example we’ll use the ISA500 altimeter as shown here, however the same process works for any Impact Subsea sensor.

To set your sensor to a known communications protocol, have the sensor on a bench with the connector pointing upwards.

Take your communications and power cable and connect it to the sensor. Once connected and once power is supplied, you want to rotate the sensor three times within the first 10 seconds. That will set the sensor to RS232 9600 baud.

If you have a sensor with V3 firmware or newer if you continue the rotations beyond three and go up to a minimum of six rotations, the sensor will be set to RS485 9600 baud at which point you can connect through your serial interface into your computer and find the sensor within the seaView software.

Once you’re into the seaView software you can configure the sensor to have any permanent communications protocol and baud rate that you require.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

► LETS CONNECT: ◄

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT

Underwater Altimeter, How do I know the reading is accurate? – Transcript

I mentioned the ISA500 outputs range so it does a measurement; long distance, high accuracy. It can also output energy and correlation values for each reading it takes.

On the screen we show that as a colour bar chart. You can see that bar chart moving slightly with the altimeter pings, the yellow proportion of the bar chart is the energy that’s been received back to the ROV / AUV Altimeter – ISA500 from the energy it’s sent out into the water and the green proportion of that is how much of that energy correlates really nicely.

How much of it is a nice clean sign wave coming back and how much of it has distortion on it. This can be used, or thought of, as a trust factor for the distance reading. If you get a distance reading like this and you’ve got a lot of energy coming back, it’s quite a long yellow bar and most of it is green, there’s a high probability that that’s a very good reading.

It’s a really nice clean signal coming back. The underwater altimeter is certain, confident that the reading is correct. If you get a reading back where the yellow bar is very short, it would indicate only a small amount of energy has come back or if you get a reading back where the green bar is quite short, it suggests very noisy readings come back and if you get one where it’s low energy and low correlation it suggests it’s a bad reading, one that should have a low trust factor applied to it.

It gives you a little bit more knowledge than just pure distance reading.

ISA500 Underwater Altimeter – How do I know the reading is accurate? This is just one question we hope has been answered for you, if you have more please watch the full film here.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT

Does suspended sediment interfere with the altimeter and its ability to get readings? – Transcript

The last item you can change on the acoustic side is your detection mode. On the detection mode we have several options, the two main ones being; first echo and strongest echo.

First echo works by transmitting a pulse of sound and as soon as it hears any return coming back it’ll use that trigger on and give you a range reading. That works really well in enclosed spaces such as tanks that we have here today.

The other option is strongest echo so if you select strongest echo the ISA500 will send out an acoustic pulse, it’ll listen to every single echo that comes back again and it’ll select one of the highest amplitudes and use that to lock on and give you a range measurement. This is really useful for open water, if you’re working in the sea or in a lake then this is ideal. Using the strongest echo method we’ll send out the ping, it may get smaller returns from fish.

It will then ignore all the smaller returns, focus on the seabed and give you that range reading. Using the strongest echo detection method ensures great stability when you’re in open water.

That’s about everything on the acoustic side. You can also set up an analog output if you want a scale voltage to be output from the ISA500 relative to the ranges measured and set this up there. You can set up multi-echo outputs so if you want the ISA500 to output more than just a single reading, you want it to output every single echo that it hears going back for the first 10 echoes or the first five echoes, you can configure that here.

The connection, you can configure it for 232485 or 485 terminated and you can set the baud rate and we get down to the output.

This is just one question we hope has been answered for you, if you have more please watch the full film here.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

LETS CONNECT:

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT

Which altimeter is right for me? – Transcript

This week we’re going to focus on looking at our range of underwater altimeters which is the ISA500 range.

One of the questions we often get asked by people first approaching us to learn more about the ISA500 altimeter is; ‘Which altimeter is right for me?’

In the ISA500 range we have around about 11 different configurations of altimeter so this range is different housing materials, different housing configurations and some without housings at all. What I’ll do initially is just talk you through some of the options that are available.

What does the forward looking, titanium altimeter look like?

One of the altimeters, this is the ISA500 in titanium and we refer to this as the forward-looking housing as the transducer looks straight out the end of it and this is the first model we launched back in 2015 and since then we’ve added additional models to the range.

The ISA500 in titanium, forward looking has the capability to measure up to 120 meters away from the seabed. Depending on the the seabed type you may actually get a longer range than this. We’ve had up to 175 meters when we have a rocky seabed which is a really good acoustic reflector to get long range measurement capability and you also get a very high degree of accuracy.

The ISA500 itself actually resolves range to 0.7 millimeters then rounds up the nearest millimeter. There’s a little example in the background here running.

We’ve got an ISA500 in our test tank just here, measuring distance here so you can see the distance being measured on the screen there. It’s measuring about 0.628 meters and so you can see the last digit there, that’s the millimeter value and you see it’s very stable very accurate.

As the altimeter is moved just slightly you’ll see that value change up and back down towards the base of our tank. The ISA500 provides long-range capability and very high degree of accuracy as well.

Optionally integrated into the altimeter is heading pitch and roll and so you can see that being fed out here, we’re heading to magnetic north and pitch and roll as well so it’s a magnetic north that’s accurate plus or minus half a degree and the pitch and roll is accurate to 0.2 degrees.

What does the right angled, titanium altimeter look like?

That’s the ISA500 in titanium, forward looking. We also do the same sensor, the same capabilities in terms of range and accuracy in what we call the right-angled housing configuration. Essentially instead of having the transducer pointing forward it points out to the side. This is quite a useful configuration if you want to put the ISA500 altimeter into a slimline form factor vehicle such as an AUV or if you want to put it onto a towed tool or towed sensor such as a magnetometer and it’s the right kind of profile to fit within the nose cone and point down to the seabed and give you range.

What does the plastic altimeter look like?

Then we also do the altimeter ISA500, in acetal plastic and forward-looking configuration and acetal plastic, right-angled configuration. The dimensions and capabilities in terms of range and accuracy are exactly the same as the titanium counterparts, the only things that change are the weight gets a little bit lighter in the plastic and also the depth rating.

The titanium sensors as standard, are depth rated to 6,000 meters, in acetal plastic they’re depth rated to 1,000 meters so still more than sufficient for a lot of shallow water application work.

Hopefully you know which altimeter is right for you now? This is just one question we hope has been answered for you, if you have more please take a look at the Altimeter Academy.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

LETS CONNECT:

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT

Does the altimeter take a multi echo output? – Transcript

In seaView we provide you with a multi echo output so you can click on this little multi echo button here and pull up a separate graph. This graph here will show you every echo the ISA500 hears going back across the range it sends a single ping out into the water and it listens to what comes back.

A lot of the time, if you’re in open water you’ll send a ping out into the water, it will travel, hit the seabed and come back again you just get one single return.

If on the other hand, you’re operating in a small test tank like we are today it sends one ping out then that ping then bounces hits the base of the tank bounces back, hit’s the top of the water, bounce back to base again, it sits there bouncing back and forth and for that reason the ISA500 ends up seeing a whole series of echoes going back.

This is just one question we hope has been answered for you, if you have more please watch the full film here.

► OUR PRODUCTS ◄

► SUBSCRIBE ◄

LETS CONNECT:

👉 LinkedIn

👉 Twitter

👉 Facebook

👉 Instagram

► GET IN TOUCH ◄

EMAIL: info@impactsubsea.co.uk

PHONE: +44 (0)1224 460 850

Monday – Friday, 9AM – 5PM GMT