The article presents the results of a large scale design space exploration for the hybridization of two off-road vehicles,
part of the Future Tactical Truck System (FTTS) family: Maneuver Sustainment Vehicle (MSV) and Utility Vehicle (UV). Series hybrid architectures are examined.
The objective of the paper is to illustrate a novel design methodology that allows for the choice of the optimal values of several vehicle parameters. The methodology consists in an extensive design space exploration, which involves running a large number of computer simulations with systematically varied vehicle design parameters, where each variant is paced through several different mission profiles, and multiple attributes of performance are measured. The resulting designs are filtered to choose the design tradeoffs that better satisfy the performance and fuel economy requirements. At the end, few promising vehicle configuration designs will be selected that will need additional detailed investigation including neglected metrics like ride and drivability.
Several powertrain architectures have been simulated. The design parameters include the number of axles in the vehicle (2 or 3), the number of electric motors per axle (1 or 2), the type of internal combustion engine, the type and quantity of energy storage system devices (batteries, electrochemical capacitors or both together).
An energy management control strategy has also been developed to provide efficiency and performance. The control parameters are tunable and have been included into the design space exploration.
The results show that the internal combustion engine and the energy storage system devices are extremely important for the vehicle performance.
This paper presents the development of an advanced concept for a next generation military vehicle based on state of the art technologies. The vehicle's platform will be directly suitable for high mobility applications for instance: Special Forces missions, Marine reconnaissance missions, and commercial racing in events such as Bajas and the Paris - Dakar. The platform will be a 10000 -14000 lbs high-speed multi-purpose vehicle, designed for extreme off-road operation. A completely new suspension concept is expected to be developed and the new vehicle topology will accommodate a new generation hybrid-electric power train. The dynamic performance targets are 125 mph off-road and 0-60 in 7 seconds. The concept design will focus also on survivability mainly through the use of a new vehicle topology (herein referred to as "island") specifically designed to enhance crew protection. The "island" topology consists in locating the powertrain and other vehicle equipment and subsystems around the crew compartment. Thus, even in the event of an external shield penetration the crew compartment remains protected by the surrounding equipment which serves in an additional role as a secondary shield.
The paper presents vehicle specifications, performance capabilities, simulation models and virtual models of the vehicle.
A large scale design space exploration can provide valuable insight into vehicle design tradeoffs being considered for the U.S. Army’s FMTV (Family of Medium Tactical Vehicles). Through a grant from TACOM (Tank-automotive and Armaments Command), researchers have generated detailed road, surface, and grade conditions representative of the performance criteria of this medium-sized truck and constructed a virtual powertrain simulator for both conventional and hybrid variants. The simulator incorporates the latest technology among vehicle design options, including scalable ultracapacitor and NiMH battery packs as well as a variety of generator and traction motor configurations. An energy management control strategy has also been developed to provide efficiency and performance.
A design space exploration for the family of vehicles involves running a large number of simulations with systematically varied vehicle design parameters, where each variant is paced through several different mission profiles and multiple attributes of performance are measured. The resulting designs are filtered to remove dominated designs, exposing the multi-criterial surface of optimality (Pareto optimal designs), and revealing the design tradeoffs as they impact vehicle performance and economy. The results are not yet definitive because ride and drivability measures were not included, and work is not finished on fine-tuning the modeled dynamics of some powertrain components. However, the work so far completed demonstrates the effectiveness of the approach to design space exploration, and the results to date suggest the powertrain configuration best suited to the FMTV mission.