AI-based Object Detection and Tracking Software for UAV Surveillance & SAR

Using ViDAR for Surveillance at Sea

Feature Article by Sentient Vision Systems

Sentient Vision Systems has released the following article detailing the use of ViDAR (Visual Detection and Ranging) to help intercept illegal activities, provide advanced warning of threats and save lives at sea.


Using ViDAR for Surveillance at Sea

If you can’t see it, then you can’t protect yourself against it – whatever ‘it’ happens to be. And it doesn’t matter what domain you’re talking about.

For Sentient Vision Systems one of the key challenges lies at sea. The company helps its customers build up a picture of what’s out there, and then identify which of the multiple targets they’re looking at could represent some sort of threat or target. It does this on land as well, but let’s focus on the maritime domain for the time being.

The surveillance problem has a number of dimensions, all of which overlap:

  • Humanitarian – essentially Search and Rescue: detecting small boats that may be adrift and dismasted; detecting survivors in the water when only their heads may be visible; doing all this in a high sea state; and then, the hardest bit, doing it all at night. Also searching flotsam and jetsam after a natural disaster to spot survivors and even distressed livestock
  • Law enforcement – detecting manned as well as unmanned surface craft that could be fishing illegally, or travelling very fast with a cargo of illicit narcotics or contraband; detecting buoys which mark illegal fishing nets or contraband stashes; detecting semi-submerged smuggling craft loaded with narcotics or contraband; doing this in a high sea state; and, of course, doing it at night when criminals anticipate a lower risk of being detected and intercepted
  • Military – the same, except that the cost of failure can be much higher and more immediate: stealthy, autonomous unmanned vessels carrying sensors or offensive weapons, or even just crammed with high explosive; manned or unmanned semi-submersibles carrying terrorists or the appropriate mix of sensors and effectors; stealthy manned surface vessels moving to attack a friendly vessel; swarms of manned or unmanned vessels, possibly moving very fast and positioning for a concerted attack on a friendly vessel.

Any subject matter expert could add to this list, and probably shouldn’t: things start getting classified very quickly in the surveillance space.

The solution a customer adopts depends, naturally, on two main things: the immediacy and scale of the threat, and the resources the customer can bring to bear on the problem. But two things in turn will always underpin that solution: the need for Situational Awareness; and the fact there will never be enough money to satisfy every need.

All of this Sentient Vision Systems understands very well. The proven technology in its solutions addresses both issues.

The company is possibly best known as the developer of ViDAR, for Visual Detection and Ranging, which is the world’s first passive optical radar. This can be implemented as a software solution and integrated with a platform’s existing Electro-Optic and Infrared (EO/IR) sensors and mission management system (MMS), or as an external sensor/processor pod whose output is integrated with the platform’s MMS. It can be added to a surface ship but has been used mainly so far aboard manned and unmanned aircraft and helicopters.

What ViDAR does is to help build up situational awareness so that operators know exactly what’s out there. And it does so more efficiently and quickly than any other system, so it can significantly reduce time on station, time spent airborne and all the maintenance and crew readiness time issues that go with supporting an airborne SAR or surveillance capability.

How does it do this? ViDAR is an artificial intelligence (AI) product that employs Sentient AI and machine vision expertise built up over more than 20 years. It’s a Wide Area Motion Imagery (WAMI) system that examines every pixel in every frame in an EO/IR sensor’s imagery feed in real time to detect sub-pixel-size targets that a human operator would miss, regardless of the resolution of the sensor.

The ViDAR technology has already been proven on manned and unmanned platforms in service with the U.S. Coast Guard (USCG), Royal Australian Navy (RAN), Australian Maritime Safety Authority (AMSA), Mexican Navy and other coast guards. They have proven that ViDAR has a success rate of more than 96% at sea: that is, it will pick up targets as small as a human head in the water 96% of the time in up to Sea State 6 using an EO/IR sensor to scan the sea surface. The USCG has used ViDAR successfully to help it intercept drug smugglers using semi-submersibles which have only a small portion visible above the surface and are almost impossible to find using traditional radar.

When it detects the target, ViDAR puts a thumbnail of it on the screen of the operator’s MMS including its bearing and range. The operator can then slew the aircraft’s primary search sensor to examine the target more closely, while ViDAR continues to autonomously seek and process targets.

A typical ViDAR installation has a field of view of up to 180o. An airborne platform traveling at 90kts at about 1,500ft can very efficiently scan a surface swath up to 40nm wide and detect almost anything inside that zone. Similarly, flying at 5,000ft increases the swath width to about 84nm for larger targets. A single aircraft such as a helicopter or a UAV, operating off a ship, can build up situational awareness very quickly and provide early warning of emerging asymmetric threats around the ship itself.

How significant is ‘significantly’ when we’re talking operating costs?

Depending on the platform’s airspeed and altitude, ViDAR can help an operator cover a specific search area more than 300 times larger than a similar aerial platform using traditional EO/IR sensors and visual search techniques. Or it can search a specific area more than 30 times faster. Depending on how persistent the search or surveillance operation needs to be, the aircraft can be back at base in a fraction of the time, reducing its exposure to weather and sea, reducing engine, airframe and sensor wear and tear and reducing the amount of time human operators spend airborne. Or it can remain airborne and help build and maintain a highly detailed common operating picture (COP) of the operating area.

ViDAR can also download its feed in real time to a ground-based imagery analyst which means the airborne platform can be unmanned, which is how the USCG uses it aboard the Insitu Scan Eagle. And its integration and size, weight and power (SWAP) requirements are low.

Compared with an active radar sensor, the combination of ViDAR and an EO/IR sensor has important advantages. Firstly, it is entirely passive, so surveillance subjects don’t know if they’re being watched. Secondly, high sea states badly affect a radar’s detection performance against small targets – ViDAR is proven to operate up to sea state 6. Thirdly, it can detect targets such as stealthy surface vessels that are designed to avoid radar detection.

So, to summarise, an optical radar such as ViDAR provides continuous, wide-area surveillance of every bit of sea within sight of an airborne surveillance platform. It can detect targets that are invisible to radar or extremely hard to spot. And it’s passive, which means it doesn’t betray its presence to potential targets.
It’s also more economical: ViDAR reduces operator workload and fatigue; surveillance and search and rescue operations can be conducted faster and more efficiently, which reduces operating costs significantly.

However, there are no magic bullets – ViDAR still needs to be part of a suite of sensors and processors, but operational experience has proven that it works and makes a significant difference in SAR, law enforcement and military operations. ViDAR helps operators see ‘it’, whatever ‘it’ is, which is the vital first step towards protection, arrest or rescue.

To learn more, contact Sentient Vision Systems: Visit Website Send Message View Supplier Profile
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