Design of an electromechanical propulsion system for mobile robots and future vehicles

Introduction – Transportation accounts for about a quarter of energy use [1], so efficiency improvements in energy conversions allow reductions in fuel consumption and pollutant emissions of internal combustion engines used for vehicle propulsion. Our previous works [2-5] were devoted to important issues like energy storage techniques, power converters, hybrid vehicle configurations and zero-emissions-vehicles (ZEVs) powered by batteries, supercapacitors or fuel cells. A substantial gain in vehicle efficiency is primarily a matter of improved vehicle design and only secondarily depends on engine type and efficiency. In fact measures like reductions of vehicle mass, aerodynamic drag and rolling resistance contribute to less power and mass needed for both engine and drivetrain. The authors are now focused on innovative propulsion systems [6-8] in order to achieve greater vehicle efficiency and higher safety in transportation means (i.e. the propelling force is independent of drag between traction wheels and road ― useful especially in bad weather conditions