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To realize the accurate tracking of the vehicle speed in the process of vehicle speed tracking, a neural network adaptive robust output feedback control (NAROFC) method for the driving robot is proposed. Firstly, considering the dynamic modeling error of the mechanical leg and the time-varying disturbance force, the dynamic model of the driving robot is established. Besides, an Extended State Observer (ESO) is designed to estimate the uncertainty and constant disturbance of modeling parameters in the system. In addition, the recurrent neural network (RNN) is used to estimate the time-varying disturbances existing in the system. Finally, the system control rate is redesigned with an ESO-designed adaptive robust controller, and the switching controller is combined to realize output feedback control. The stability of the designed controller is proved by Lyapunov theorem.

The noise, vibration, and harshness (NVH), also known as noise and vibration (N&V), is a critical feature for customers to assess the performance and quality of vehicles. NVH characteristics are higher among factors that customers use to judge the vehicle's quality.This book sets out to introduce the basic concepts, principles, and applications of the NVH development and refi nement of Battery Electric Vehicles (BEV), Hybrid Electric Vehicles (HEV), and Fuel Cell Electric Vehicles. Each type comes with its own set of challenges.

To improve torque management algorithms for drivability, the powertrain controller must be able to compensate for the nonlinear dynamics of the driveline. In particular, the presence of backlash in the transmission and drive shafts excites sharp torque fluctuations during tip-in or tip-out transients, leading to a deterioration of the vehicle drivability and NVH. This paper proposes a model-based estimator that predicts the wheel torque in an automotive drivetrain, accounting for the effects of backlash and drive shaft flexibility. The starting point of this work is a control-oriented model of the transmission and vehicle drivetrain dynamics that predicts the wheel torque during tip-in and tip-out transients at fixed gear. The estimator is based upon a switching structure that combines a Kalman Filter and an open-loop prediction based on the developed model.

Due to the multitude of external design constraints, such as increasing fuel economy standards, and the increasing number of global vehicle programs, developers of automotive transmission controls have to cope with increasing levels of powertrain system complexity. Achieving these requirements while improving system quality, reducing development cost and improving time to market is a very challenging task. To achieve this goal, a rapid prototype controller was used to develop a new transmission clutch temperature model. This model is used to detect clutch surface overheating, improve design and enhance shift quality.

Many experiments have demonstrated that clutch overheating is a major cause of clutch deterioration. Clutch friction material deterioration not only leads to clutch failure, but also causes poor shift quality. Unfortunately, it is not practical to monitor each individual clutch temperature in a production vehicle due to high costs or technical challenges. This paper introduces a proposal for a virtual clutch temperature sensor to monitor the real time clutch temperature changes in Chrysler transmissions with PWM solenoid based control systems. Both vehicle and laboratory dynamometer (dyno) tests demonstrate that the model results match very closely with the thermocouple temperature measurements under many different driving conditions. The real time virtual temperature sensor provides a tool for clutch surface overheat protection and for design improvement and enhancement to shift quality.

The Chrysler Ultradrive four-speed transaxle 41TE was the first production transmission to pioneer fully adaptive direct clutch-to-clutch electronic controls without overrunning clutches. "Single stage" high flow PWM solenoids have been used for transmission control since 1989 and still being used in the later-developed 545RFE and 62TE transmissions. The proposed target volume-based shift control method allows the usage of flow-based control device such as PWM solenoids to implement torque-based control strategy. Vehicle test results with this new method have shown excellent shift quality and improved system consistency.

Energy transport in nanostructures differs significantly from macrostructures because of classical and quantum size effects on energy carriers. Nanostructure-based materials such as superlattices have shown significant increases in thermoelectric figure-of-merit ZT compared to their bulk counterparts due mainly to the reduced phonon thermal conductivity of these structures. Materials with a high ZT can be used to develop efficient solid-state devices that convert waste heat into electricity. Superlattices grown by thin-film deposition techniques, however, are not suitable for large scale applications. Nanocomposites represent one approach that can lead to high ZT through both thermal conductivity reduction and possibly low energy electron filtering. This paper presents theoretical studies on thermoelectric properties in semiconducting nanocomposites, aiming at developing high efficiency thermoelectric energy conversion materials.

Piston design that incorporates the heat pipe cooling technology may provide a new approach for piston-temperature control. A simulated piston crown that contains an annular reciprocating heat pipe is developed to investigate the effect of heat pipe cooling on the piston crown temperature distribution. For this purpose, a reciprocating engine testing apparatus is designed and constructed. The experimental study focuses on the static and dynamic operational characteristics of the heat pipe and its cooling effect on the simulated piston crown under different power input. The experiment results indicate that a piston crown incorporating a heat pipe can yield a uniform temperature distribution in the ring-bank area of the piston crown. The testing results would also provide the needed information for a possible piston design that incorporates the heat pipe cooling technology for improved thermal-tribological performance.

Temperature variation and heat transfer phenomena in the intake port of a spark ignition engine with port injection play a significant role in the mixture preparation process, especially during the warm up period. Cold temperatures in the intake port result in a large amount of liquid-fuel film. Since the liquid-fuel film responds at a slower speed than the gas-phase flow during transient operations, the liquid-fuel film acts as a fuel sink (or source) and can degrade the vehicle's driveability, fuel economy, and emissions control. In this work, a one-dimensional, unsteady, multicomponent, multiphase flow model has been developed to study the mixture formation process in the intake port for a modern, multipoint-fuel-injection, gasoline engine. The droplet, liquid film and gas-phase mixture temperature variations and the effects of charge air, initial fuel and port wall temperatures involved in generating the air-fuel mixture are examined.

For spark ignition engines, the fuel-air mixture preparation process is known to have a significant influence on engine performance, exhaust emissions and fuel economy. In this work, a one-dimensional, unsteady, multicomponent, multiphase flow model has been developed to study the mixture formation process in the intake manifold for a port-injected gasoline engine. The model consists of three major parts: a gas-phase model, a multicomponent droplet vaporization model and a liquid-film model. Three subsets of equations are solved by a hybrid Eulerian-Lagrangian, explicit-implicit scheme. The model not only quantitatively identifies the effects of each parameter on the final mixture but also shows the interactive influences of three phases of the mixture during the process. As a development and calibration tool, the model helps to understand the behavior of multiphase flow in the intake port, and can give guidelines toward achieving more efficient, clean and smooth engine operation.

Most of the current fuel supply specifications, including the key parameters in the transient fuel control strategies, are experimentally determined since the complexity of multiphase fuel flow behavior inside the intake manifold is still not quantitatively understood. Optimizing these specifications, especially the parameters in transient fueling systems, is a key issue in improving fuel efficiency and reducing exhaust emissions. In this paper, a model of fuel spray, wall-film flow and wall-film vaporization has been developed to gain a better understanding of the multiphase fuel-flow behavior within the intake manifold which may help to determine the fuel supply specifications in a multi-point injection system.