Scania’s NXT concept vehicle represents a vision of the future
NXT has been designed as a prototype for testing and evaluation, but also to exhibit to get feedback on the concept. But what would this new creature look like? “Many of the features have been designed with the future always-online generation in mind. Their lives will be closely intertwined with technology, and we think this concept vehicle will appeal to them,” says Transport Designer Michael Bedell, Scania. “From the start, our aim was that it should not be perceived as aggressive, but be assertive and command respect as a vehicle in traffic. At least in the beginning, some may try to provoke the autonomous vehicle to stop, and it should be clear that NXT is on the move.”
How NXT communicates with passengers and those around it
A key consideration with self-driving vehicles is the machine interaction with other road users, and, in the case of buses, also with passengers.
NXT is Scania’s vision of what the future for transport in cities could be. It is a self-driving electric vehicle that can change shape from a bus to a distribution truck to a refuse collector.
Communication for bus passengers
Many of the interior features in the concept vehicle’s bus module compensate for the lack of the driver. Lights in the ceiling inform passengers when the vehicle is about to start or stop. NXT is also equipped with a warning system to alert those disembarking of unsafe oncoming traffic.
Upon entering, passengers can immediately see information about public transport connections and communicate with a human operator via a sphere-shaped touchpad. Information on an additional screen could include, for example, news updates or tourist recommendations and tips.
Sensor system with a 360-degree view
The autonomous concept vehicle is equipped with state-of-the-art integrated sensor systems for driving and traffic detection. Cameras on the front, back and sides are complemented by radar and lidar – light detection and ranging – systems.
“This integrated sensor system enables the vehicle to scan the entire surroundings and obtain a 360-degree view,” explains Transport Designer Michael Bedell, Scania. “At present, vehicles may fall short of human processing capacity but in future, they will be superior to what humans can achieve simply because they will have access to much more information and the ability to process this mass of data.”
Warning system for surrounding pedestrians or cyclists Communication for bus passengers
People in the vicinity of the vehicle will be alerted to its approach by LED lighting throughout the front, sides and back. It also confirms through lighting and sound that it is aware of a passing pedestrian or cyclist. This is done in three steps: Initially the vehicle will signal through a laser beam that it has observed the person. If that warning goes unnoticed, the vehicle will amplify LED-lighting and finally emit a sound.
“The communication between a self-driving vehicle and the people moving around it has been highlighted as especially important since many pedestrians on city streets make, what to many, is an almost an unconscious contact with drivers of trucks and buses before crossing streets,” says Bedell. “However, when that slight nod from a driver disappears, it is clear how much value that contact adds. This is something that we need to program autonomous vehicles to handle.”
How Scania engineers designed a vehicle for 2030 and beyond
What today is Scania’s NXT concept vehicle started with the idea of finding a solution for future transport in cities. A group of Scania engineers rose to the challenge by developing a vehicle that represents a vision of the future. “When you ask ten different people about the future, you will get ten different answers. At the end of the day, no one knows what will happen in 2030,” says NXT Project Manager Robert Sjödin. “Throughout this project, we have brought together experts and made many choices that have lead us to this idea of what the future of urban transport could be.”
INTERCHANGEABLE FUNCTIONAL MODULES. Scania has now revealed the result of its two-year future-oriented project – the eight-metre-long NXT concept vehicle. What sets the concept vehicle apart is the use of separate drive modules, which control and steer the vehicle, and functional modules, which can be used for different applications. Energy is stored in each functional module’s battery unit, meaning that, when transitioning between applications, each functional module can be removed and replaced by another with a fully charged battery.
BATTERIES UNDER THE FLOOR. The cylindrical cell batteries – commercially available today – are placed under the bus floor and have a total capacity of 162 kWh. Combined with the low vehicle weight, simulations show that the vehicle can achieve a range of around 245 kilometres. “Normally batteries are placed on the roof or in the engine compartment. Instead, we make good use what otherwise would be a dead space,” says Linus Ährlig, NXT Technical Project Manager, Scania. “This placement is also beneficial for weight distribution.”
LOW WEIGHT. The bus module has the capacity for 20 seated passengers and 55 in total. Without a driver’s area, the entire interior area can be used to carry passengers. The bus body consists of one single composite material module, reducing the total vehicle weight to less than eight tonnes.
CRAB STEERING MODE. Ährlig continues: “Thanks to the hub engines and fully steered wheels, the concept vehicle is extremely agile on city streets. With crab steering mode, the front and rear wheels turn in the same direction. Crab steering enables the bus to align perfectly with the pavement for ease of passenger entry and exit.” The axle distance of six metres is similar to that of a standard bus. In contrast, however, the four fully steered wheels permit a turning radius of just 10.5 metres, better than many passenger cars.
SOLAR PANELS ON THE ROOF. For added power, the roof of the concept vehicle has been equipped with a limited number of solar panels. If the entire 20 m2 roof is covered with solar panels, this has the potential to generate nearly 3 kW of added power.
INFRARED HEATING SYSTEM. Innovation has also been the guiding light inside the vehicle. To save on power-consuming heating, NXT has been equipped with an infrared heating system, which, compared with traditional convection heaters, reduces energy requirements by 60 per cent. The system is substantially lighter as well. Rather than heating indoor air, the infrared heaters keep passengers warm while also warming seat fabrics for added comfort.