1st ICAI 2020

International Conference on Automotive Industry 2020

Mladá Boleslav, Czech Republic

Hydro-pneumatic suspension system will allow the vehicle to change the stroke of each shock absorber in the real-time. This system will be used to level the whole platform into its original ground clearance after loading it up. This levelling process will be done automatically or by operator of the vehicle (depending on the situation) and it can be done in both possible ways – by lowering or increasing the ground clearance of the vehicle. Another use of this system will be vehicle body roll management for example during cornering or when driving on a tilted slope (shown in the Figure 3). Figure 3: Vehicle on a tilted slope - one shock absorber puts wheel into compression and the other to extension. Up to 8° of slope the platform stays levelled and the cargo stays on its place.

Source: own elaboration (2019)

It will be later decided whether mechanical anti-roll bars will be added or if this purely hydro-pneumatic solution will be used. The next level of system usage will be active control of each absorber. For example, to compensate pitch of the vehicle during braking and accelerating. This can help to prevent damage or loss of the cargo, especially for bulk cargo such as sand. The whole system will be robust and will take into account the current necessary parameters such as the centre of gravity position of the entire vehicle, which may change while driving - by changing the load or changing its position for bulk materials. 2.1.3 Battery design concept of TUL modular platform The autonomous mobile platform project addresses two approaches of traction battery design. The first approach is based on the use of a simplified design with 14 battery modules with a total amount of 196 prismatic lithium cells (shown in the Figure 4). Used NMC chemistry cells utilizes automotive VDA-PHEV2 format with nominal volumetric energy density of 456 Wh·l -1 and gravimetric 204 Wh·kg -1 . Total nominal battery energy is 36 kWh. The advantage of this particular design is that the robustness of used cells makes possible to omit the active temperature management of the battery without significantly affecting its battery life. The most significant disadvantage is the reduction of charging rate outside the ideal battery operating

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