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The testing and certification of vehicles in succession to their development are usually achieved on chassis dynamometer testbeds. In this context, the execution of test cycles shall be performed as automatised as possible even if vehicles with manual transmission powertrain are under test. A particular challenge is the vehicle driveaway from standstill by actuating clutch and engine in accordance with each other. In this paper a non-linear decoupling multivariate control scheme based on feedback linearisation considering the accelerator and clutch pedal positions as manipulated variables is proposed. To obtain the required vehicle model for control in a time-saving manner, the clutch torque transmissibility and engine torque characteristic are identified incorporating a Wiener model structure from efficiently designed drive manoeuvres. By applying this model structure, the dynamics can be considered separately from the static non-linearity, which is beneficial for control. In addition to the successful demonstration of the presented workflow and an examination of the controller performance on vehicle system simulation software, the robustness with respect to parameter uncertainties is investigated. • An automated vehicle driveaway with manual transmission is considered. • A simple vehicle model is identified from efficiently designed drive manoeuvres. • A non-linear decoupling control scheme based on feedback linearisation is applied. • A successful simulation examination of the identification and control is shown. • The robustness with respect to parameter uncertainties is investigated. [ABSTRACT FROM AUTHOR]

In this work a new approach for a fully automated calibration of nonlinear PID controllers and feedforward maps is introduced. Controller design poses a particularly challenging task in the application to internal combustion engines due to the nonlinear controller structure, which is usually prescribed by the manufacturer of the engine control unit (ECU). A dynamic local model network is used to represent the actual physical process as its architecture can beneficially be adopted for scheduling of the nonlinear controller parameters. The presented calibration technique uses a genetic algorithm to calibrate the nonlinear PID controller and a static model inversion to determine the feedforward map. Closed-loop stability is taken into account by incorporating a Lyapunov function. Finally, an example demonstrates the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Highlights • A novel approach to analyze parameter-dependent separatrices in SRAM cells is proposed. • The method is constructed based on boundary-value problems solved via continuation techniques. • In this way, families of separatrices can be approximated in a computationally efficient manner. • The method is tested in a typical SRAM bit cell via the continuation platform COCO. • A comprehensive modelling of the cell is carried out using the EKV equations for CMOS transistors. Abstract The continued scaling of CMOS semiconductor technology, together with the corresponding reduction of operating voltages, pose serious challenges for SRAM arrays regarding susceptibility to parameter variations, reduction of stability margins and reliability of read and write operations. One approach, alternative to various noise margin definitions, is to characterize the robustness of SRAM cells via the computation of stability boundaries, also referred to as separatrices. These curves define threshold voltages producing a flip in the logical state of an SRAM cell, which may lead to data loss due to disturbances, e.g. during read operations. The present work proposes a numerical approach to compute families of parameter-dependent separatrices based on path-following (continuation) methods, exploiting the geometric features of one-dimensional stable manifolds around saddle equilibria. The proposed approach is tested on an SRAM cell whose mathematical description is carried out in detail, based on the EKV (Enz, Krummenacher and Vittoz) equations for MOS transistors. In addition, the present work includes a comprehensive numerical study of the effect of parameter perturbations on separatrices, in a computationally efficient manner. [ABSTRACT FROM AUTHOR]