Probing the Parameter: Quick Attacks and Swarm Search
The Echthros section commander whose observation position sits astride the southern approach road is more excited than fearful at the sound of rockets bursting, rattling through the modest house his team have turned into a bunker. He feels vindicated. Two weeks of chastising his men to stay away from the windows and not even consider leaving the building. Two weeks of demanding that they remain civil to the surly family now living in one room, whose home it is. Two weeks of ensuring that the sentry is always positioned back from the window watching down the road to the north through the mesh curtains. Two weeks of watching the oblivious naval police at the checkpoint two hundred metres away surreptitiously extorting fresh vegetables from the farmers during the daylight hours when they can move.
The section commander happens to be taking his turn ‘on stag’ watching the road to the west when his eye is drawn to an odd movement. He spots something just above the roof of a house a hundred metres beyond the checkpoint on one side of the road. As he watches intently, he sees a pizza box sized object briefly appear above a building on the opposite side of the road. Then a peculiar almost spiderlike bushy object the size of a small car appears further down the road itself. His first reaction is professional curiosity, then amusement at the alarm and confusion evident in the agitation of the naval police sentry, but he does not hesitate to reach for the field telephone and call his section to ‘stand-to’.
The phone is an analogue model, nearly 40 years old, a quirk of their Brigadier General who fought in the mountains as a young officer. The section commander calmly describes the chaos at the checkpoint in front of him, reports that the naval police have fired a few shots and wrly comments that they are now demonstrating that “discretion is the better part of valour”. Listening Australian systems hear nothing of his conversation with headquarters, nor of their instruction to let the approaching vehicle pass. The Echthros commander looks around. Three of his men peer back expectantly over the lip of the sandbag bunker they have constructed within the room. Another looks outward over a belt fed machine gun through a porthole they have cut in an interior wall. He gives them a reassuring silent signal as they hear first the pounding of the running feet of the police, then the whine of a drone hopping over their building, next the rumbling sound of rubber treads and finally, moments later, barely perceptible sound of large plastic wheels – all quietly trundling past. Twenty seconds later, there is a shattering burst of explosions from behind them followed by the sound of debris raining onto the roof.
The defenders plan is working. An automatic grenade launcher sited to fire in defilade along the lateral street to their rear has hit the leading Australian Xtrak, which has exploded spectacularly. Through one of the many small loopholes that his men cut in the internal walls, the commander can look rearwards along the street in the direction of the town and the airbase. Broken tracks and wheels lie smoking on the junction where the southern approach road meets the lateral road. The following six wheeled Polywheeler moves cautiously across his view, it’s turret rotating as it scans to locate the threat – and again his Echthros comrades positioned in-depth behind him fire from their carefully concealed cellar position. The home ground advantage pays off once more as the second UGV is also destroyed, and he thinks he observes two objects flying from the wreck before his view is gradually obscured by smoke. Unseen by him, the two Xtraks immediately following the stricken vehicles have scuttled off their track have begun to generate smoke vapour.
Without human instruction, the contact initiates an immediate action. Standby UAV lift off from their position on the ground amongst the rice stalks in a field several hundred metres back: several unarmed Reccedrones and a Gundrone12 with its 6.5mm weapon and 40 mm grenade launcher. As witnessed 41
by the enemy section commander all the platforms around the contact begin generating smoke. Like the two closest XTraks, the four UGV moving along the parallel track move in to cover. On the back of all, and also, remarkably, from the crippled Polywheeler in front of them, canisters the size of hat boxes pop open and from them rise spindly hollow spheres. These mini drones and their cameras are surrounded by matrices of light plastic rods that protect it from collisions with walls.
The football sized Spheridrone2’s hop over their ‘parent’ UGV and move close to the walls of the buildings on either side of the street. Guided by a common preloaded memory of the shape of every building in the area and the location of every window and door they begin to move from aperture to aperture, above the wisps of the spreading smoke vapor clouds. They hover at each, moving erratically like a ping-pong ball bouncing in an upward jet of air at the fairground, rotating to capture images across 360° and compressing them for instant transmission back to Darwin via mesh radio and satellite link. Each pair of searching drones is overwatched from the opposite side of the street by an Xtrak, it’s weapon selector set to the 40 mm tubes and less lethal projectiles.
Civilians peering fearfully out from their houses at the Spheridrones also notice little flags flying from their protective cages carry the image of the mythical creature that is the symbol of the region. From their over-watching positions loudspeakers on Xtraks make announcements in the Filia language: “Stay inside”, “Open windows and doors so we can see you are only civilians”. All this happens without the involvement of the humans who are focused on the lethal systems and the battle just begun.
The thermal camera on one of the Reccedrones circling around the rooftops records the muzzle flash of the Echthros weapon and in microseconds this is matched with the data from static acoustic sensors and those on the Polywheeler350 on the parallel track. The target building is presented for engagement authority to a distant operator in Darwin within couple of seconds, but for some reason the authorisation to use lethal force is not immediately forthcoming from Australia. The backup team in the swamp are there for exactly such moments and one of the soldiers concealed in the mangroves merely kilometres away touches his screen to provide the authority. Again, in fractions of a second, algorithms create, compare and assess tactical options and in another moment, select. It has compared times of flights of the available indirect weapons, assessed the relative risks of unmasking different systems, calculated the risks and probabilities associated with different manoeuvres of the UGV close to the enemy position – including hypothesising different supporting enemy positions. It achieves in three seconds far more than the most tactically adept human commander could weigh up in 30 minutes.
One of the rearmost Xtraks on the backstreet lane parallel to where the contact has occurred is already tucked beside a building less than 200m away. It elevates its tubes to a high angle and fires three rounds in succession, adjusting between each with slight track movements and shifts of elevation. With only one of the encapsulated propelling charges ignited, the time-of-flight is a few short seconds. The bombs burst straddling the crossroads and instantly blanket it in a dense cloud of hot smoke that blinds both visual and thermal sensors. With a speed beyond the slickest human section, the AI launches an attack at the moment the third smoke bomb impacts.
From the backstreet lane and screened by the billowing hot smoke, an Xtrack and a Polywheeler accelerate into the open. They travel the hundred metres that brings them to the cross junction, stopping there with the heavy tracked UGV just protruding around the corner building and the lighter six wheel vehicle sheltering behind it with its RWS arm raised to engage over the top. Neither can ‘see’ nor ‘be seen’, but this is of no consequence. They fight from ‘memory’. The smaller vehicle skid-turns towards the building where the Echthros grenade launcher is sited in a basement window. The RWS on the larger vehicle swings the same way. There is no hesitation.
The Xtrak ‘knows’. An 81 mm mortar bomb set to ‘delay’ and fired horizontally at full charge rocks the vehicles back on its tracks and smashes through the wall of the building 35m away. An instant later it detonates in the room beyond, shocking but not injuring the enemy launcher crew in their sandbag bunker in the cellar below. Even as the bomb detonates the machine gun on the RWS begins to fire, not in bursts, but a rapid series of single shots calculated to strike at 15 cm intervals across the front of the building starting at ground level and repeating at successively higher levels to distribute bullet strikes across the front of the building. The Echthros launcher crew flinch and duck from the fragments and dust being thrown through the firing loophole and rush to switch the weapon sight to thermal. By the time its circuitry has cooled sufficiently to see through the now-cooling smoke that is drifting into the bunker, it is too late. The all-electronic Polywheeler is faster, it discerns the loophole, the launcher and the helmeted shape of the heads of the Echthros crew and puts a long burst of fire through them all. Beneath the muzzle of the RWS the smaller UGV skids slightly as it aligns itself, then a second 81 mm mortar bomb vanishes into the basement loophole and an instant later blast and debris bounce right back out.
The engagement has all occurred behind the Echthros section commander in the forward observation position on the south road, who is still hunkered down undetected in his position and can hear more drones hovering in the streets outside. He speaks softly on the field telephone to his company commander who is in a command post in a basement of a building on the edge of town. The junior describes what he has heard of the fight. The Echthros senior offers praises the him for keeping his nerve and orders him to continue to lay low. “well done for not being located – I need you to keep hidden and tell me when you have a target big enough for the artillery or the hunter-killer drones – and after that wait until you have something worth using your anti-tank launcher on!”.
The Echthros company commander then turns to the IT specialist who sits at an adjacent table in the underground room has made his headquarters. “Okay, time to deploy the jammer-bot – send it in passive mode.” The specialist gets up from the table, walks up the concrete basement stairs and up out of a fire door towards a large pile of rubbish. He pulls on a sheet of canvas to expose a wheeled UGV the size of a wheelie bin laid on its side. He bends to operate the power button on the control panel and waits for several small LED to turn green before heading back underground. As the fire door closes behind him the machine hums away down the centre of the street to its assigned operating area, a small open park where it will constantly move while alternately listening for mesh transmissions and then transmitting jamming signals on multiple bands.
The sounds of the firing and detonations from the first contact on the south approach road are soon joined by similar sounds from a few hundred metres further north on the central road. There the Echthros defenders follow the same pattern, allowing the leading UGV’s to pass the forward observation post positions. The engagement area is 150m behind that post and when the first two Australian UGV are both exposed, an APC concealed in a shopfront destroys them both in a few seconds with two bursts of its cannon. This time there is no system observing towards the enemy vehicle and it remains unlocated. The AI moves the following UGV into cover off the road to observe while the autonomously launched Spheridrones begin their systematic search.
When the Echthros APC crew report both their success in destroying two targets and the growing smoke cloud drifting from where the UGV’s came, their platoon commander orders one of his own drones launched. A Marine clambers out of their sandbag bunker built inside the building, picks a drone launched tube from a sandbag surrounded pile of ammunition, and cautiously opens a rear door and steps outside. There he rests one end of a tube on the ground, angled towards the threat and presses the launch button. With a modest pop and woosh a projectile is thrown skywards. The Marine is already back in cover before the drone reaches the height where wings deploy, and its thruster begins to spin. As it automatically begins to circle the camera in its nose starts to transmit thermal images to the platoon commanders monitor. The birds-eye view of his position and the streets around puzzles him. Nestled between buildings and up against them on the side of the streets he can see things that don’t belong. The bright spots of hot barrels and duller glow of warm wheels and tracks draw his eye and he discerns the indistinct rectangular shapes of the UGV despite the foam and fabric camouflage attenuating the heat signature. More robots. What he can’t see, and he searches for, is soldiers. Perhaps a little further to the rear? He decides to use the flying munition to continue to look and moves his joystick to shift the drone’s search. Peering intently at the view to the west from several hundred metres overhead he spots one or two moving platforms, but as he swivels the camera towards them, a firework-like starry brightness floods the screen and the image begins to spin. The cannon on an Australian CUAS-MAVOC have done their work.
On the northern approach road, the one nearest the deception beach landing, the initial contact comes 30 seconds later than at the two Echthros perimeter positions further south – and unfolds differently. The sentry on duty in the observation post shows a little more initiative but less caution. When he sees a strange machine approaching down the street, he grabs his smart phone to capture an image. He fails to notice another overwatching vehicle 250 m away, well behind the Xtrak. To get a good picture he moves up to the open window and is immediately detected by the thermal optics of the RWS on the Polywheeler which automatically lays the weapon barrel on him. Fortunately for the sentry, in the several seconds of delay before an operator in Darwin authorises lethal engagement, he has moved back from the window to the field telephone to make a report. The burst of fire into the room misses him and the cannon shells detonate on the rear wall. Deafened and shocked, he feels a stinging sensation on the back of his neck, and when his enquiring hand is withdrawn it is covered with blood. Before a further burst of fire follows, adrenaline powers a swift move to another room as he yells unnecessarily to alert his section commander.
The sentry heads, as rehearsed many times, to the loophole that is the alternate position for watching the road. Fate dictates that as he lifts his weapon to use the optical sight to get a better look at the still moving Xtrak, he sees the two fake MAVOC appear further behind it. He shouts: “tanks, comrade commander, I see tanks”. One of his teammates cowering in the sandbag bunker in the first room passes on the alarm using the field telephone. It is the last report from the position. On the far side of the street, the first Xtrak has turned through 90° and elevated its 81mm tube array to point at head height at the house which hides the observation post. The little vehicle jumps back violently from the recoil of the first 81 mm mortar bomb being fired, which smashes through the cinderblock wall to detonate at ceiling height, blowing smoke and debris out of every window. The two tracks of the UGV move slightly in opposite directions traversing the vehicle before it fires and jumps again, this time it’s bomb penetrating to blow the front door into the street, before turning back the other way to deliver a bomb that peels the roof of the building back as it explodes. The house begins to burn.
As the robotic platforms probe the Echthros perimeter force, the human operators in Darwin concentrate on overseeing the lethal systems, while the ‘swarm-search’ of the immediate area by unarmed drones continues autonomously. Reccedrones hover above and Spheridrones move around buildings like bees moving around flowers. Systematically they move along walls, constantly moving and stopping, all the while capturing and transmitting compressed geo-located thermal or visual spectrum images. The pictures themselves reveal mostly empty rooms, sometimes fearful civilians cowering and vitally, occasional signs of enemy presence or defensive preparations. Where there is suspicion of a Echthros position, the AI prompts an operator in the Darwin control room to authorise a closer inspection of ambiguity. Approval brings an UGV closer to knock open a door or has a Polywheeler fire a less-lethal rubber ring foil munition to break windows and allow drones enter and check inside.
When the unarmed Spheridrones appear in the smoke and close in on or enter Echthros positions, they draw fire from unnerved defenders. One or two drones are destroyed this way and others are physically knocked down by hand, often continuing to transmit images for long enough to confirm enemy presence. When gunfire destroys a drone the moment of loss of signal is matched to a firing source revealed to array of acoustic sensors, giving similar confirmation. The AI then offers lethal engagement options to operators, initially by default applying 40mm enhanced-blast munitions from a Gundrone12, as their non-fragmenting detonations are less likely to damage nearby Spheridrones. As the unarmed drones move clear of newly identified enemy positions the latter are treated with 81mm mortar bombs fired directly from an overwatching Xtrak. Once the identified positions have been engaged several Perchdrone1 are deployed to nearby walls and roofs to observe, with a Gundrone12 perched nearby while the UGV fleet pushes forwards, reflecting the vulnerability of uncrewed platforms that remain static.
Except to authorise lethal engagement, the RAS data communication is almost entirely one-way and back-to-base, mesh radio to the nearest UGV, fibre-optic link back to the microsatellite dish, then upwards and back to Australia. There at Home Control a virtual three-dimensional ‘wire model’ of the entire town and every building in it is progressively ‘detailed’ by being overlaid with captured images that form rich mosaics in the areas scanned by the flying robots. The model has already been ‘populated’ by cross-referencing against databases of public records, social media activity, utility bills and similar sources – the work of a joint team of Filia and Australian human environment specialists. A synthesis of ‘human intelligence’ data, with imagery from the drones, including battle damage assessments after lethal engagements, all overlaid with professional assessment of likely tactical disposition quickly narrows down the likely enemy remaining positions in the area that has been ‘swarm searched’.
The perimeter battle is complete in less than 10 minutes. This was close reconnaissance by drone ‘swarm-search’ backed up by UGV lethality. The One-star back in Darwin has no illusions that the all Echthros positions have been eliminated. Nor does he aspire to that yet. He does have confidence that most or all of them have been located. The loss of no more than a dozen uncrewed systems has prepared a doorway to the outer defences. Opening it can wait.
Dr Charles Knight developed this narrative as part of concept development and design activity with EOS Defence Systems to inform current and future Australian autonomous and remote operations technology development. Many of the concepts covered in this narrative are being actively pursued by EOS Defence and numerous other Australian industry players.
Images by James Wilson-Knight
Dr Charles Knight
Dr Charles Knight explores how to reduce the risks and costs of combat amongst structures and populations – an interest sparked when as a Parachute Regiment officer he was tasked to develop urban combat and subterranean capabilities for confronting the Soviets in the German city of Hildesheim. He is a senior researcher at the University of NSW, Canberra and an adjunct lecturer at Charles Sturt University. HisMasters research analysed vulnerabilities to asymmetric attacks in citiesandhis PhDexamined coercion duringcounterinsurgency– both informed by field research in the Lebanon and Cambodia, as well as by uniformedservice with the RAF, British and Omani Armies and in Asia. In Australia he served in 1 Commando Regiment, commanded 2/17 Bn, Royal New South Wales Regiment, spent a decade in the Special Operations development branch, drove reform of close combat training and wrote the Australian Army urban doctrine.