LiDAR technology: Providing lightning fast security

Responsive innovation allows LiDAR technology to keep pace with ever-changing customer needs, says Rick Wakeham, Senior Technology Manager, OPTEX.

Many of us are familiar with the concept of laser technology in high-security systems.

In movies, robbers often hang from ceilings or perform acrobatic moves to dodge invisible infrared beams that crisscross floors or doorways, without setting off sophisticated alarms.

Whilst this is largely a figment of a directors’ imagination, the use of infrared to warn of potential security threats is nothing new. 

Today, advanced LiDAR (Light Detection and Ranging) technology is central to securing buildings, perimeter fences and tunnels because it is accurate, precise and creates real-time detection alerts.

What is LiDAR technology?

At its simplest, LiDAR systems fire pulses of infrared light towards an object and record the ‘time of flight’ – or how long it takes for the light to bounce back to the sensor.

The infrared pulses pass through a polygonal or multifaceted mirror spinning rapidly, dispersing the beams of light every quarter or eighth of a degree, allowing it to sweep across a target area.

The tighter the pulses, the more sensitive and quicker the detection becomes, making it especially useful for indoor security.

When the light pulses hit an object, they are reflected back to the sensor and recorded.

The security system’s processor then calculates the distance of objects using the time taken for the light to return, which enables it to determine the x,y position of the object.

This collection of data points is called the LiDAR point cloud. Algorithms are used to determine the exact location and size of the objects. 

The data points produced, in combination with the rapid speed of detection, enable the system to be calibrated so that only genuine objects or threats are detected. These features also allow the system to filter out or ignore irrelevant items, such as vegetation or small animals.

LiDAR’s evolution in security

LiDAR sensors for security were introduced in 2009 by OPTEX and were used to improve camera-based surveillance systems. Cameras rely on what can be seen and often struggle in the dark, fog, heavy rain and other adverse conditions.

LiDAR technology, on the other hand, can detect at night or in extreme conditions. It is reliable because it has a different wavelength from sunlight, headlights or fluorescent lights; there is no interference, much like using a radio channel that no one else is listening to.

Early LiDAR sensors also replaced the conventional point or line detection of lasers and cameras with a fan-shaped infrared detection area.

The new shape was possible using software developed by OPTEX engineers.

Now, LiDAR technology can pinpoint the object’s location, determine its size and distance and in all weather conditions. And if an intrusion was detected, surveillance teams could be notified in real time for the first time without false alarms.

However, there were gaps between the semi-circular detection zones and numerous overlapping beams were needed to achieve good, comprehensive coverage, which was expensive.

So the algorithm was adjusted to produce a rectangular detection zone. The simpler design, with fewer overlaps, allows for easier system design, alongside cost savings.

A wall of security

Modern LiDAR sensors, still produce invisible, high-resolution, customisable virtual detection walls or planes which today have multiple uses both internally and externally.

They can provide guaranteed detection over large perimeter fences, which is particularly useful for walls or fences surrounding critical infrastructure sites such as airports or power stations.

Different detection patterns can be used at various points along the perimeter.

In one specific area, it can monitor for people loitering; in another, it may simply detect the presence of an object, or it can track movement around the whole perimeter and provide early warning of an approaching vehicle, for example.

Indoors, the flat planes of REDSCAN LiDARs can cover server racks and cages in data centres, or can be used to monitor narrow aisles in a warehouse or skylights and glassfronted walls in commercial and office buildings.

Two types of LiDAR

Since LiDAR’s market entrance in the mid-2000s, most advances have come through software development, although hardware improvements, such as in-built cameras, have also emerged.

Notably, 3D LiDAR is now being adapted for some security purposes. 3D LiDAR emits multiple layers of light beams, which not only locate objects but also reveal details such as height, size, shape and movement.

It can identify where people are inside a room and whether they are standing, sitting or leaving the room using x,y,z coordinates.

The depth and richness of data produced by 3D LiDAR is extremely useful for highly complex situations where detail matters, such as in driverless car navigation, and is commonly used in mapping terrains for ecological studies, archaeological digs and surveys.

However, analysing such high volumes of data requires substantial processing power and typically requires server-based analytics, which is highly expensive.

More worrying, though, is the delay or latency in analysing this data in order to determine a valid threat. In a security setting, speed is of the essence.

Fast detection

By contrast, 2D LiDAR processes the data at the edge, concentrating solely on what is necessary for security purposes. This more focused data means that sufficient processing power can be integrated into the sensors themselves.

This reduces hardware, costs and data transfer latency. The analysis is significantly faster and an object’s distance and position are known within 100 milliseconds only.

In real-world settings, real-time detection is everything. A flash drive passed into a secure area, a vehicle moving surreptitiously into a blind spot or a trespasser running onto railway tracks takes just moments.

Intelligently configured 2D LiDAR sensors can rapidly process object size, location and distance to alert teams quickly and enable them to respond without delay. Every second counts – especially when teams need to travel to the opposite end of a building or across an industrial site.

Seamless integration

For many security staff real-time visual verification is now far simpler.

LiDAR provides a reliable trigger, sending an alert to the team when an intrusion is detected and the video footage can be live-streamed to a guard’s mobile device via any ONVIF-compliant network, system or IP device.

These systems also generate detailed logs for post-event review and potential prosecution of intruders.

Modern ONVIF-compliant platforms allow LiDAR systems to integrate as easily as CCTV cameras into an existing security system. For engineers, launching a Video Management System (VMS) is a straightforward, plug-and-play process.

For high security environments, such as data centres, government buildings or prisons, the sensors are now IEE802.1x compatible.

What’s next?

LiDAR is an extremely reliable solution for detection. It will enhance many security systems because, unlike CCTV, it is unaffected by weather, light and temperature.

Its software can be tailored to recognise potential intruders approaching a building, a malicious insider accessing a data rack or even a fallen rock on a railway track, while ignoring wildlife and foliage.

Few other technologies can provide the stable and reliable detection needed for the narrow corridors commonly found next to perimeter fences and inside retail or data centre facilities.

False alarms are reduced and alerts are delivered at lightning speed. So, why do many in the industry still rely on traditional CCTV alone?

Many engineers remain unsure about LiDAR technology. After decades of installing CCTV cameras, they are comfortable configuring what they know: The concept of a visible camera system.

LiDAR, by contrast, can feel less intuitive. Engineers are naturally wary as incorrectly installing a system can put their clients’ security at risk. There is, however, a solution.

OPTEX has worked with many engineers and learnt how to simplify and support the LiDAR installation process. The installation of LiDAR is also becoming easier and the company is now opening a network of training centres, where engineers can gain hands-on experience of how easy they are to install.

With training facilities in Spain, France and in the UK, along with online training courses and a team of technical experts across EMEA, consultants, installers and system designers can learn how LiDAR works, how LiDAR is installed and ultimately how they can offer their customers a smarter, faster and more secure solution for any project.