54 Digest | IDV Viking UGV Modular architecture As a multirole defence UGV, modularity is inherent to the Viking’s subsystem layout: payload, sensor and comms integrations may change between missions, and maximising payload area and capacity were key targets from its earliest, blank-sheet design stages. Standard military power and data interfaces are also installed to aid this, and the control software is programmed to ‘discover’ payloads as they are integrated, and open new pages in the GCS accordingly to manage those payloads once fitted. “Those could be CBRN, ISTAR or other payloads, and we’ve also targeted a payload swapping time of less than one hour with the open payload bed, as customers are envisaging buying one family of UGVs and rerolling their platforms as requirements change in the field,” Davis says. Viking’s systems mount on a tubularframe chassis, designed by IDV-R and manufactured by Safety Devices, a nearby specialist in chassis and roll cages. This allows different body panels to be mounted, as defence organisations vary as to how much armour they want on their UGVs. Those prioritising weight savings can opt for aluminium body panels, and those wanting more protection can cycle up through the established classes of armoured vehicle protections for their desired types and thicknesses of body material. Davis continues: “The vehicle is low-profile, at 0.9 m height to the payload bed, so it’s hard to spot, compared to most vehicles. Combine that with its ability to run silently on electric power and to navigate without Lidar – or anything else actively sending out signals – and it’s stealthy enough that you don’t always need to protect it. “But if it’s going to be used for critical intelligence or ordnance, you don’t want it to be taken out, so allocating some of the 750 kg payload capacity to armour can be a good idea sometimes.” The UGV is assembled in-house at IDV-R’s workshop in Nuneaton, where the company can manufacture some tens of units per year, although an industrialisation process is underway (with considerable practical expertise on the matter coming from the new parent company, IDV) to make the Viking faster and less costly to produce. Hybrid 6x6 powertrain The Viking’s engineers wanted a vehicle with high mobility without resorting to tracks, as that would have reduced reliability, maintainability, and the speed of on- and off-road operations. This was a critical factor in choosing the six-wheel configuration, as was a shared desire for maximum gap crossing and soft ground capabilities. “Six-wheel-drive means very low ground pressure, and with the right power-to-weight ratio, enables climbing sand dunes,” Maloney says. “We’ve also chosen an independent, double wishbone suspension with dual-rate coil springs around adjustable dampers – both for mobility and to not shake payloads to pieces when we’re crossing very rough terrain. If something like a CBRN payload or remote weapons station fails when you need it, because it has suffered too much shock and vibration, it can be catastrophic.” The platform is designed with Ackermann steering, as IDV-R finds that skid-steering, the more popular choice among similar-sized defence UGVs, often results in excessive friction on tarmac or other grippy surfaces. When 7501000 kg payloads are added atop the mix, problems such as tracks coming off or burst tyres can ensue. “For added manoeuvrability, we’ve got four-wheel steer, which we switch to at 20 kph for tighter turning radii, with the Ackermann two-wheel steering at higher speeds, so it’s not too twitchy,” Maloney says. The four-wheel steer mode’s turning circle is 7 m kerb to kerb, while the two-wheel steer’s is 12 m. The parallelhybrid powertrain occupies most of the space inside the chassis, with June/July 2024 | Uncrewed Systems Technology The Viking runs on a parallel, hybrid powertrain, built around a Kohler diesel engine and a YASA motor-generator, which run into a 6x6 transfer box from Compact Orbital Gears
RkJQdWJsaXNoZXIy MjI2Mzk4