Design of the University of Idaho Formula Hybrid Vehicle 2015-01-0414
Over the last five years the Vandal Hybrid Racing team at the University of Idaho has developed a compact, lightweight, and mass centralized vehicle design with a rule-based energy management system. Major areas of innovation are a close fitting frame design made possible by the location of major components and engine modifications to improve performance. The innovative design features include a custom designed engine, battery pack and simplistic hybrid coupling system. The vehicle also incorporates a trailing link suspension, and realization of a rule-based Energy Management System (EMS) which determines the power split of the combustion and electric systems. The EMS oversees the operation of the Lynch electric motor and the YZ250F engine that is housed in a custom crankcase. The battery pack can initially store 2 MJ of energy in a single 50 lb. lithium polymer battery pack that is located underneath the cockpit. The gas tank of the vehicle holds 33 MJ of energy in a 1.5 inch wide, 1.01 gallon tank immediately behind the cockpit. The resulting vehicle weighs 550 lbs. without the driver, achieves a top speed of 55 mph on the 75 meter acceleration track, and exhibits a hybrid fuel economy on the endurance course of 29 mpg. This is achieved by the implementation of a supervisory controller that turns on and off the electric motor and throttles the internal combustion engine in response to vehicle's speed and the battery pack's state of charge. The vehicle described in this paper won the 2014 FHSAE competition in Loudon, New Hampshire. It is currently undergoing comprehensive performance testing that will inform the design and operation of a next generation vehicle.