H∞ Measurement-feedback Control for Systems with Input and Measurement Delays

纸专注于与不仅输入延期而且测量延期为系统发现 H 测量反馈控制法律。和伪测量， Krein 空间被介绍以便在我们把原来的问题变换成最小化的以后，重新组织的技术能被利用。最后，我们得到需要的控制器并且看到分离原则也是适用的推迟系统到某程度。

Finite Frequency Fuzzy H∞Control for Uncertain Active Suspension Systems With Sensor Failure

This paper investigates the problem of finite frequency fuzzy H_∞ control for uncertain active vehicle suspension systems, in which sensor failure is taken into account. TakagiSugeno(T-S) fuzzy model is established for considered suspension systems. In order to describe the sensor fault effectively, a corresponding model is introduced. A vital performance index,H_∞ performance, is utilized to measure the drive comfort. In the framework of Kalman-Yakubovich-Popov theory, the H_∞ norm from external perturbation to controlled output is optimized effectively in the frequency domain of 4 Hz-8 Hz to enhance ride comfort level. Meanwhile, three suspension constrained requirements, i.e., ride comfort level, manipulation stability,suspension deflection are also guaranteed. Furthermore, sufficient conditions are developed to design a fuzzy controller to guarantee the desired performance of active suspension systems. Finally, the proposed control scheme is applied to a quarter-vehicle active suspension, and simulation results are given to illustrate the effectiveness of the proposed approach.

A comparing design of satellite attitude control system based on reaction wheel

The disturbance caused by the reaction wheel with a current controller greatly influences the accuracy and stability of the satellite attitude control system. To solve this problem, the idea of speed feedback compensation control reaction wheel is put forward. This paper introduces the comparison on design and performance of two satellite attitude control systems, which are separately based on the current control reaction wheel and the speed feedback compensation control reaction wheel. Analysis shows that the speed feedback compensation control flywheel system may effectively suppress the torque fluctuation. Simulation results indicate that the satellite attitude control system with the speed feedback compensation control flywheel has improved performance.

An ILMI Approach to RFDF for Uncertain Linear Systems with Nonlinear Perturbations

The robust fault detection filter design for uncertain linear systems with nonlinear perturbations is formulated as a two-objective optimization problem. Solvable conditions for the existence of such a robust fault detection filter are given in terms of matrix inequalities (MIs), which can be solved by applying iterative linear matrix inequality (ILMI) techniques. Particularly, compared with two existing LMI methods, the developed algorithm is more generalized and less conservative.An illustrative example is given to show the effectiveness of the proposed method.

Immunity clone algorithm with particle swarm evolution

Combining the clonal selection mechanism of the immune system with the evolution equations of particle swarm optimization, an advanced algorithm was introduced for functions optimization. The advantages of this algorithm lies in two aspects. Via immunity operation, the diversity of the antibodies was maintained, and the speed of convergent was improved by using particle swarm evolution equations. Simulation programme and three functions were used to check the effect of the algorithm. The advanced algorithm were compared with clonal selection algorithm and particle swarm algorithm. The results show that this advanced algorithm can converge to the global optimum at a great rate in a given range, the performance of optimization is improved effectively.

Cardiac electrical activity imaging of patients with CRBBB or CLBBB in magnetocardiography

A new method for the imaging of cardiac electrical activity in patients with complete right bundle branch block （CRBBB） or complete left bundle branch block （CLBBB） is investigated using magnetocardiographic recordings of the surface of the body. This is based on the assumption that an equivalent single-current dipole moves along the unblocked bundle branch, whose position in the measurement plane is expressed in terms of the maximum and minimum, as well as the maximum gradient value of the measured magnetic field. The trajectory of the moving dipole on the measurement plane is indicative of theexcitation conduction of the CRBBB or CLBBB subject during ventricular depolarization and repolarization, which is deduced by comparing each change between the dipole moment and the maximum current density in a corresponding pseudo-current density map. In summary, this method can distinguish CRBBB from CLBBB subjects by means of the dipole depth and two dipole moment components. The possibility of visualizing the excitation conduction in a CRBBB or CLBBB subject during ventricular depolarization and repolarization is then discussed.

Online gait programming of humanoid walking via NMPC

In order to satisfy the requirement of realtime gait programming of humanoid walking with foot rotation,a kind of modified Nonlinear Model Predictive Control (NMPC) scheme was proposed. Based on setting suitable kinetic and kinematic virtual constraints of Single Support Phase (SSP) and three subphases of Double Support Phase (DSP) ,complex realtime gait programming problem was simplified to four online NMPC dynamic optimization problems. A numerical approach was proposed to transform the dynamical optimization problem to the finite dimensional static optimization problem which can be solved by Sequential Quadratic Programming (SQP) . It can be concluded from simulation that using this method on BIP model can realize online gait programming of dynamic walking with foot rotation and the biped stability can be satisfied such that there is no sliding during walking.

Compound Product of Hypermatrices

The semi-tensor product(STP)of matrices is generalized to multidimensional arrays,called the compound product of hypermatrices.The product is first defined for three-dimensional hypermatrices with compatible orders and then extended to general cases.Three different types of hyperdeterminants are introduced and certain properties are revealed.The Lie groups and Lie algebras corresponding to the hypermatrix products are constructed.Finally,these results are applied to dynamical systems.

An MPC-based manoeuvre stability controller for full drive-by-wire vehicles

Aiming at the actuator time delay caused by the drive-by-wire technology,a novel manoeuvre stability controller based on model predictive control is proposed for full drive-by-wire vehicles.Firstly,the future vehicle dynamics are predicted by a twodegree-of-freedom vehicle model with input delay.Secondly,in order to prevent the vehicle from destabilizing due to excessive side slip angles,the determined ideal yaw rate and side slip angle are tracked simultaneously by optimizing the front wheel angle and additional yaw moment.Moreover,in order to improve the trajectory tracking ability,a side slip angle constraint determined by phase plane stability boundaries is added to the cost function.The results of Matlab and veDYNA co-simulation show that the regulated yaw rate can track the reference value well and the side slip angle decreases.Meanwhile,the trajectory tracking ability is improved obviously by compensating the time delay.

Real-Time nonlinear predictive controller design for drive-by-wire vehicle lateral stability with dynamic boundary conditions

Due to flexible drive-by-wire technology,vehicle stability control can improve handling and lateral stability under extreme conditions.However,this technology can also increase the probability of random transmission delay.This paper proposes a nonlinear model predictive control(NMPC)strategy to improve vehicle stability and compensate for the random time delay.First,by combining the nonlinear dynamic characteristics and driver behavior,we obtain a stable region of the yaw rate and the sideslip angle under complex driving conditions.Second,an NMPC controller is designed to track the reference values in the identified stable region to improve the handling and lateral stability.Finally,the actuator receives the optimized control sequence and compensates for the random time delay of the transmission channel.CarSim/Simulink simulation and hardware-in-the-loop experiment results show that the proposed controller with dynamic boundary conditions can better track the expected value of the yaw rate and suppress the sideslip angle under low adhesion road conditions.

Contracted product of hypermatrices via STP of matrices

An equivalent definition of hypermatrices is introduced.The matrix expression of hypermatrices is proposed.Using permu-tation matrices,the conversion between different matrix expressions is revealed.The various kinds of contracted products of hypermatrices are realized by semi-tensor products(STP)of matrices via matrix expressions of hypermatrices.