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In this article, we assess the string stability of seven 2018 model year adaptive cruise control (ACC) equipped vehicles that are widely available in the US market. Seven distinct vehicle models from two different vehicle makes are analyzed using data collected from more than 1,200 miles of driving in car-following experiments with ACC engaged by the follower vehicle. The resulting dataset is used to identify the parameters of a linear second order delay differential equation model that approximates the behavior of the black box ACC systems. The string stability of the data-fitted model associated with each vehicle is assessed, and the main finding is that all seven vehicle models have string unstable ACC systems. For one commonly available vehicle model that offers ACC as a standard feature on all trim levels, we validate the string stability finding with a multi-vehicle homogeneousplatoon experiment in which all vehicles are the same year, make, and model. In this test, an initial disturbance of 6 mph is amplified to a 25 mph disturbance, at which point the last vehicle in the platoon is observed to disengage the ACC. The data collected in the driving experiments is made available, representing the largest publicly available comparative driving dataset on ACC equipped vehicles. [ABSTRACT FROM AUTHOR]

This article develops autonomous-driving vehicle control with a composite velocity profile (CVP) planning. An innovative technique of path planning is presented in the vehicle coordinates to allow complete lane change from any position at the origin lane to the center of the target lane. A technique of control is also presented to allow lane-change control design with vehicle speed planning. The CVP consists of longitudinal and lateral velocity profiles in time and planar geometric domains in the vehicle coordinates, respectively. This article also develops an autonomous-driving control framework with decentralized speed/lateral control using the CVP. The stability of the autonomous-driving control system is mathematically proved. Some experimental results on a test vehicle are also presented to demonstrate the utility of the proposed autonomous-driving vehicle control with CVP planning. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive tube-based nonlinear model predictive control (AT-NMPC) approach to the design of autonomous cruise control systems. The proposed method utilizes two separate models to define the constrained receding horizon optimal control problem. A fixed nominal model is used to handle the problem constraints based on a robust tube-based approach. A separate adaptive model is used to define the objective function, which utilizes least square online parameter estimators for adaption. By having two separate models, this method takes into account uncertainties, modeling errors, and delayed data in the design of the controller and guaranties robust constraint handling, while adapting to them to improve control performance. Furthermore, to be able to implement the designed AT-NMPC in real-time, a Newton/GMRES fast solver is employed to solve the optimization problem. Simulations performed on a high-fidelity model of the baseline vehicle, the Toyota plug-in Prius, which is a plug-in hybrid electric vehicle, show that the proposed controller is able to handle the defined constraints in the presence of uncertainty, while improving the energy cost of the trip. Moreover, the result of the hardware-in-loop experiment demonstrates the performance of the proposed controller in a real-time application. [ABSTRACT FROM AUTHOR]

Intensive scaling for VLSI circuits is a key factor for gaining outstanding performance. However, this scaling has huge negative impact on the circuit reliability, as it increases the undesired effect of aging degradation on ultradeep submicrometer technologies. Nowadays, Bias Temperature Instability (BTI) aging process has a major negative impact on VLSI circuits reliability. This paper presents a comprehensive framework that assists in designing the fortified VLSI circuits against BTI aging degradation. The framework contains: 1) the novel circuit level techniques that eliminate the effect of BTI (these techniques successfully decrease the power dissipation by 36% and enhance the reliability of VLSI circuits); 2) the evaluation of the reliability of all circuit level techniques used to eliminate BTI aging degradation for 16 nm CMOS technology; and 3) the comparison between the efficiency of all circuit level techniques in terms of power consumption and area. [ABSTRACT FROM PUBLISHER]

Rear-end collision is a very serious problem in modern traffic situations, and there have been a great number of research reports on the longitudinal control method for road vehicles. In many cases, however, the control problem is formulated under platoon configuration and for some predictable noncollision situations. For predictable collision situations, regional and hierarchical approaches have been employed, but these approaches render difficulties due to ignorance for modeling error and logical error in a decision process. In this paper, the vehicle control for collision avoidance is studied with two control objectives, i.e., minimization of the safety distance error and regulation of the relative velocity between two vehicles. For this, a longitudinal controller using terminal sliding mode (TSM) with hierarchical structure is proposed for rear-end collision avoidance. The TSM is employed to achieve convergence in finite time, while the hierarchical approach is used for the system to accommodate the intelligence of the driver to handle various situations. The effectiveness of the proposed control scheme is verified by software simulations. [ABSTRACT FROM AUTHOR]

A new design for the collision prevention system based on cascaded fuzzy inference system (CFIS) for lane-changing maneuver and car-following is proposed. The lane-changing is combined with car-following to save the processing time of the lane-changing maneuver. The distance and speed relative to the vehicle in front or in target adjacent lane are measured by the spread spectrum radars and applied to the collision prevention system. The output acceleration or deceleration rate obtained from the CFIS collision prevention system is based on the characteristics of the vehicles. Monte Carlo simulations were conducted to demonstrate that the CFIS collision prevention system could provide a safe, reasonable, and comfortable drive for car-following and lane-changing. The system characteristics for car-following, lane-changing, and emergency braking are verified [ABSTRACT FROM AUTHOR]

Focuses on the design of automated vehicle guidance control. Implementation of guidance tasks using several individual controllers; Schematic diagram of the vehicle guidance control systems; Intelligent automotive guidance system; Determining control mode; Two-phase hybrid learning algorithm which combines genetic and gradient algorithms.

A dynamic RAM cell based on the field-effect diode (FED) is presented, and its operation is described and explained with the help of numerical device simulations. This new cell resembles the thin capacitively coupled thyristor (TCCT) cell in concept and operation, however it has important advantages. These advantages derive from the fact that the thyristor-like mode of operation of the FED is gate induced, whereas the TCCT is an actual, built-in thyristor. High read 0/1 current margin, fast write/read time, good retention, and densely packed cells are obtained. [ABSTRACT FROM PUBLISHER]