Unmanned Systems Technology 007 | UMEX 2016 report | Navya ARMA | Launch & recovery systems | AIE 225CS | AUVs | Electric motors | Lethal autonomous weapons

32 Dossier | Navya ARMA Power The power pack for the ARMA uses lithium-polymer cells with a lifetime of 1600 charge-discharge cycles, which are expected to last four years; they come from China Aviation Lithium Battery, and are integrated in a drawer system from Eve System. The ARMA is delivered to customers with 33 kWh of power, which can drive the low-voltage 15 kW motor (25 kW at peak power) for up to 13 hours, depending on the route and the speed. The motor can drive the vehicle when fully loaded up a maximum 12% slope. The drawer approach allows Navya to offer a version of the ARMA with 16 kWh depending on how long a vehicle needs to be used. This provides less power, but is lighter, so can provide around six hours of operation. There is also the option to add more power for air conditioning, for operation in hot countries for example, as this takes up to half the power of the batteries. The 33 kWh pack takes 6-8 hours to recharge, so the ARMA would operate until the charge in the batteries falls below the peak value. It then returns to base to recharge and another vehicle replaces it on the route. The power pack also contains an embedded charger and dc converters to power all the auxiliaries, making it a compact all-in-one power block. Wireless charging Navya is using an induction system for charging, which determines the battery architecture of a single pack: if there were two packs then two charging systems would be needed. The induction technology comes from a US supplier (unnamed) which also supplies systems to Nissan, Tesla and Chevrolet. Using wireless charging means the vehicle can autonomously position itself over an induction charging panel, eliminating the need for human intervention to recharge. Faster charging can be achieved by means of a plug but that of course requires manual intervention. April/May 2016 | Unmanned Systems Technology A single pack of batteries slots into the drawer in the ARMA design. Additional batteries can be added to power air-conditioning systems in hot climates The 15 kW motor drives the 2100 kg ARMA platform at speeds of up to 45 kph Wireless charging means the vehicle can position itself autonomously over an induction panel, eliminating the need for human intervention