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24 speeds, there is no need for a higher voltage system. Barthelemy describes LiFePO4 as the most stable battery chemistry they could find on the market. It works reliably across a wide range of environments, from the ice and snow north of the Arctic Circle to the desert heat of Dubai. The cells, the battery pack and the battery management system are all supplied by the same French company, an unnamed specialist in LiFePO4 chemistry. The battery pack feeds power to e-axles at the front and rear, making the EZ10 an all-wheel-drive vehicle, to maximise traction as well as boost reliability through redundancy. Each e-axle has its own inverter which feeds a motor that drives through a single-speed reduction gearbox. For its primary structure, the EZ10 has a chassis made from three grades of aluminium alloy – 6060, 6082 and ZL111T6 – which are used in different areas requiring different strengths and curvatures; S235 steel is used for the subframes that hold the suspension and e-axles to the chassis. The separate body is made from glass-reinforced plastic, and bolts on to the chassis. The chassis is symmetrical front to back, even though the body on the third-generation EZ10 is not. That is because the first two generations were built as bidirectional vehicles. With the third generation, EasyMile has gone to a unidirectional configuration, partly to avoid the cost and complexity of fitting a complete sensor system at each end and partly because there is no advantage to running a bidirectional vehicle in mixed traffic on public roads, marketing director Olivier Pairot explains. Barthelemy adds that the authorities in some countries asked them to remove the bidirectional features because their rules don’t allow beams to be projected from the rear of a vehicle, only the stop lights and so on found on normal vehicles. He notes that the rear of the vehicle is still fitted with sensors, but fewer of them and with shorter ranges, because the vehicle’s speed in reverse will be lower still. There is some lateral asymmetry, as the sliding passenger doors, naturally, have to be on the kerb side. That means putting them on the right in countries that drive on the right and vice versa, and it also affects the positions of some of the sensors. Designed for autonomous operation, the EZ10 has no seat, steering wheel or pedals for a driver, but it can be controlled if needed by an onboard safety operator using a handset, and most of the vehicles in service operate in this way to respect local regulations. The 3130 kg vehicle localises itself with centimetric accuracy in real time using the company’s own algorithm that fuses data from differential GPS, Lidars, stereo cameras, radars, IMUs and odometry. At the same time, another set of Lidars and radars scan for any objects, vehicles, animals or people that might pose a collision threat, and feed that information to the vehicle’s control software. The high-level decision-making and path-planning software is known as EZDrive, and runs on a dedicated computer, while the safety software April/May 2020 | Unmanned Systems Technology A single charge of its 40 kWh, 48V lithium iron phosphate battery will power the EZ10 for up to 16 hours with the aircon switched off or 10 with it on. A full recharge takes about 6 hours Wheelchair anchor points, in addition to the ramp, were requested by one customer and are being standardised on new- build EZ10s. This approach is being taken to many detail features as the vehicle evolves