Abstract
Public transportation and the transportation of goods in urban areas is becoming more and more complex task, especially due to increased awareness of its impact on the environment. One of the solutions could be a flexible transport system which could be fitted with different powertrain solutions, according to the region of its deployment. Croatia is a Mediterranean country and is in a need for such a solution. Its coastal cities are characterized by narrow streets which pose a problem for conventional city busses and delivery trucks. The objective of the project described in this paper was the development of a modular vehicle which could be used as a low floor minibus or as a commercial delivery vehicle fitted with an electric, hybrid or conventional powertrain and which could provide a suitable transportation solution for Croatia’s coastal cities and similar European cities. The project started in 2007 when the Chair of IC Engines and Motor Vehicles of the Faculty of Mechanical Engineering and Naval Architecture on the University of Zagreb joined forces with the newly formed company called AZ Crobus. AZ Crobus had an ambition to restart the bus production in Croatia and the idea was to offer a unique niche product along with a standard intercity bus. The development task was to develop a vehicle with a gross weight up to 6,000 kg and a high percentage of low floor area which could carry up to 35 passengers. During the development process two vehicle concepts were developed and evaluated. The better rated vehicle concept was further developed and design solutions for some critical components (axles and steering system) were developed. The cooperation between the Chair of IC Engines and Motor Vehicles and AZ Crobus ended by the end of 2008 due to financial reasons but the project was further developed on the Chair of IC Engines and Motor Vehicles. The design process was greatly supported with modern CAD tool, FEM (finite elements method) and MBD (multibody dynamics) simulation and optimization tools. The paper offers a review of the development of an innovative vehicle concept carried out in Croatia.