Delay-dependent robust stability for neutral systems with mixed discrete-and-neutral delays

摘要:This paper focuses on the problem of delay-dependent robust stability of neutral systems with different discrete-and-neutral delays and time-varying structured uncertainties.Some new criteria are presented,in which some free weighting matrices are used to express the relationships between the terms in the Leibniz-Newton formula.The criteria include the information on the size of both neutral-and-discrete delays.It is shown that the present results also include the results for identical discrete-and-neutral delays as special cases.A numerical example illustrates the improvement of the proposed methods over the previous methods and the influences between the discrete and neutral delays.

neutral systemsrobust stability
被引:21
Model predictive control for hybrid vehicle ecological driving using traffic signal and road slope information

摘要:This paper presents development of a control system for ecological driving of a hybrid vehicle. Prediction using traffic signal and road slope information is considered to improve the fuel economy. It is assumed that the automobile receives traffic signal information from intelligent transportation systems (ITS). Model predictive control is used to calculate optimal vehicle control inputs using traffic signal and road slope information. The performance of the proposed method was analyzed through computer simulation results. Both the fuel economy and the driving profile are optimized using the proposed approach. It was observed that fuel economy was improved compared with driving of a typical human driving model.

traffic signaltransportation systemssimulation resultspredictive controlcontrol systemdriving model
被引:20下载:12
Circle formation control for multi-agent systems with a leader

摘要:In this paper, we focus on circle formation control of multi-agent systems (MAS) with a leader. The circle formation is achieved based on the lead-following and the artificial potential field method. A distributed control law is given to make a group of agents form a circle and consequently achieve an expected angle. Finally, simulation results show that the proposed circle formation strategies are effective.

formation controlfield methodcontrol law
被引:19
Solving type-2 fuzzy relation equations via semi-tensor product of matrices

摘要:The problem of solving type-2 fuzzy relation equations is investigated. In order to apply semi-tensor product of matrices, a new matrix analysis method and tool, to solve type-2 fuzzy relation equations, a type-2 fuzzy relation is decomposed into two parts as principal sub-matrices and secondary sub-matrices;an r-ary symmetrical-valued type-2 fuzzy relation model and its corresponding symmetrical-valued type-2 fuzzy relation equation model are established. Then, two algorithms are developed for solving type-2 fuzzy relation equations, one of which gives a theoretical description for general type-2 fuzzy relation equations;the other one can find all the solutions to the symmetrical-valued ones. The results can improve designing type-2 fuzzy controllers, because it provides knowledge to search the optimal solutions or to find the reason if there is no solution. Finally some numerical examples verify the correctness of the results/algorithms.

fuzzy relation equationsoptimal solutionsfuzzy controllersanalysis method
被引:19
Model reference adaptive impedance control for physical human-robot interaction

摘要:This paper presents a novel enhanced human-robot interaction system based on model reference adaptive control. The presented method delivers guaranteed stability and task performance and has two control loops. A robot-specific inner loop, which is a neuroadaptive controller, learns the robot dynamics online and makes the robot respond like a prescribed impedance model. This loop uses no task information, including no prescribed trajectory. A task-specific outer loop takes into account the human operator dynamics and adapts the prescribed robot impedance model so that the combined human-robot system has desirable characteristics for task performance. This design is based on model reference adaptive control, but of a nonstandard form. The net result is a controller with both adaptive impedance characteristics and assistive inputs that augment the human operator to provide improved task performance of the human-robot team. Simulations verify the performance of the proposed controller in a repetitive point-to-point motion task. Actual experimental implementations on a PR2 robot further corroborate the effectiveness of the approach.

task performanceadaptive controlhuman operatorinteraction system
被引:19下载:1
Robust stability analysis of singular linear system with delay and parameter uncertainty

摘要:This paper deals with the problem of robust stability for continuous-time singular systems with state delay and parameter uncertainty.The uncertain singular systems with delay considered in this paper are assumed to be regular and impulse free.By decomposing the systems into slow and fast subsystems,a robust delay-dependent asymptotic stability criteria based on linear matrix inequality is proposed,which is derived by using Lyapunov-Krasovskii functionals,neither model transformation nor bounding for cross terms is required in the derivation of our delay-dependent result.The robust delay-dependent stability criterion proposed in this paper is a sufficient condition.Finally,numerical examples and Matlab simulation are provided to illustrate the effectiveness of the proposed method.

parameter uncertaintylinear systemuncertain singular systemslinear matrix inequalitysufficient conditionmodel transformationasymptotic stabilitystability criterionMatlab simulationrobust stabilitystate delay
被引:19
Non-fragile hybrid guaranteed cost control for a class of uncertain switched linear systems

摘要:This paper focuses on the problem of non-fragile hybrid guaranteed cost control for a class of uncertain switched linear systems. The controller gain to be designed is assumed to have additive gain variations. Based on multiple-Lyapunov function technique, the design of non-fragile hybrid guaranteed cost controllers is derived to make the corresponding closed-loop system asymptotically stable for all admissible uncertainties. Furthermore, a convex optimization approach with LMIs constraints is introduced to select the optimal non-fragile guaranteed cost controllers. Finally, a simulation example illustrates the effectiveness of the proposed approach.

被引:19
Colony location algorithm for assignment problems

摘要:A novel algorithm called Colony Location Algorithm (CLA) is proposed. It mimics the phenomena in biotic conmunity that colonies of species could be located in the places most suitable to their growth. The factors working on the species location such as the nutrient of soil, resource competition between species, growth and decline process, and effect on environment were considered in CLA via the nutrient function, growth and decline rates, environment evaluation and fertilization strategy.CLA was applied to solve the classical assignment problems. The computation results show that CLA can achieve the optimal solution with higher possibility and shorter running time.

被引:18
Active disturbance rejection control: some recent experimental and industrial case studies

摘要:This paper presents a summary of some recent experimental and industrial case studies of active disturbance rejection control (ADRC).ADRC is a novel disturbance estimation and rejection concept,leading to a new technology with a distinct advantage where,unlike most existing methods,disturbances,internal and external,are actively estimated and rejected.Applications of the new approach in solving industry-wide bench mark problems have led to a slew of innovative solutions.The scope of the applications shown in this paper includes motion control,robotic-enhanced limb rehabilitation trainings,fuel cell systems,and the two-mass-spring benchmark problem.Recent production line validation results obtained are also included.

被引:18下载:5
An LMI approach to robust H-infinity control for uncertain singular time-delay systems

摘要:The problem of robust H-infinity control for a class of uncertain singular time-delay systems is studied in this paper. A new approach is proposed to describe the relationship between slow and fast subsystems of singular time-delay systems, based on which, a sufficient condition is presented for a singular time-delay system to be regular, impulse free and stable with an H-infinity performance. The robust H-infinity control problem is solved and an explicit expression of the desired state-feedback control law is also given. The obtained results are formulated in terms of strict linear matrix inequalities (LMIs) involving no decomposition of system matrices. A numerical example is given to show the effectiveness of the proposed method,

linear matrix inequalitiessufficient conditionno decompositioncontrol law
被引:18
Approximation property of partition of unity and its applications

摘要:The linear combination of certain partition of unity,subordinate to certain open covering of a compact set,is proved to be capable of approximating to a continuous function at arbitrarily precision.By using proper open covering and partition of unity,the robust nonlinear controllers and adaptive laws are designed for a class of nonlinear systems with uncertainties.The states and parameters of the closed-loop systems can be stabilized in the meaning of UUB (uniformly ultimately bounded) via the robust nonlinear controllers and adaptive laws.Finally,an example shows the validity of method in this paper.

partition of unityadaptive lawscontinuous functionlinear combinationnonlinear systems
被引:17
A practical fuzzy controllers scheme of overhead crane

摘要:This paper presents fuzzy-based design for the control of overhead crane.Instead of analyzing the complex nonlinear crane system,the proposed approach uses simple but effective way to control the crane.There are twin fuzzy controllers which deal with the feedback information,the position of trolley crane and the swing angle of load,to suppress the sway and accelerate the speed when the crane transports the heavy load.This approach simplifies the designing procedure of crane controller;besides,the twin controller method reduces the rule number when fulfilling the fuzzy system.Finally,experimental results through the crane model demonstrate the effectiveness of the scheme.

overhead cranefuzzy controllersfuzzy systemdeal with
被引:17下载:1