Quantitative feedback theory and zero phase error tracking control combined robust control for radar truck leveling simulator

Radar leveling system is the key equipment for improving the radar mobility and survival capability. A combined quantitative feedback theory (QFT) controller is designed for the radar truck leveling simulator in this paper, which suffers from strong nonlinearities and system parameter uncertainties. QFT can reduce the plant uncertainties and stabilize the system, but it fails to obtain high-precision tracking. This drawback can be solved by a robust QFT control scheme based on zero phase error tracking control (ZPETC) compensation. The combined controller not only possesses high robustness, but greatly improves the system performance. To verify the effiectiveness and the potential of the proposed controller, a series of experiments have been carried out. Experimental results have demonstrated its robustness against a large range of parameters variation and high tracking precision performance, as well as its capability of restraining the load coupling among channels. The combined QFT controller can drive the radar truck leveling platform accurately, quickly and stably.

Research of Compound Controller for Flight Simulator with Disturbance Observer

A compound controller is proposed to alleviate the considerable chattering in output of zero phase error tracking controller （ZPETC）, when the flight simulator losses command data of simulation signal. Besides, the shortcomings, caused by conventional differential methods in retrieving velocity and acceleration signals, are avoided to a certain extent. The compound controller based on disturbance observer （DOB） is composed of a feed-forward controller and a feedback controller. It estimates velocity and acceleration of unknown tracking signal, and also velocity response with an approximate method for differential. The experiments on a single-axis flight simulator show that the proposed method has strong robustness against parameter perturbations and external disturbances, owing to the introduced DOB. Compared with the scheme with ZPETC, the proposed scheme possesses more simple design and better tracking performance. Moreover, it is less sensitive to position command distortion of flight simulator.

Study on Control Technology of Tendon Bionic Driving Robot System

Although traditional position-controlled industrial robots can be competent for most assembly tasks,they cannot complete complex tasks that frequently interact with the external environment.The current research on exoskeleton robots also has problems such as excessive inertia of exoskeleton robots,poor system integration and difficult human–computer interaction control.To solve these problems,this paper independently develops a tendon driving robotic system composed of a tendon driving robotic arm and an upper limb exoskeleton,and studies its control technology.First,the robot system is selected,configured,and constructed.Second,the kinematics of the robot is analyzed,and then the dynamics are studied,and the parameter identification experiment of single degree of freedom is completed.Finally,the research on zero-force control and impedance control of the robot has effectively improved the robot’s human–machine integration ability,ensured the flexibility and compliance in the process of human–computer interaction.The compliant control problem expands the usage scenarios and application scope of robots and contributes to the realization of complex operations of this group of robots in unstructured environments.

PERFORMANCE LIMITATIONS FOR A CLASS OF KLEINMAN CONTROL SYSTEMS

This paper provides preliminary results on performance limitations for a class of discrete time Kleinman control systems whose open loop poles lie strictly outside the unit circle. By exploiting the properties of the Kleinman controllers and using of Mgebraic Riccati equation （ARE）, the relationship between total control energy of Kleinman control systems and the minimum energy needed to stabilize the open-loop systems is revealed. The result reflects how the horizon length of Kleinman controllers affects the performance of the closed-loop systems and quantifies how close the performance of Kleinman control systems is to the minimum energy.

Electromechanical wave in power systems:theory and applications

The continuum model is a key paradigm describing the behavior of electromechanical transients in power systems.In the past two decades,much research work has been done on applying the continuum model to analyze the electromechanical wave in power systems.In this work,the uniform and non-uniform continuum models are first briefly described,and some explanations borrowing concepts and tools from other fields are given.Then,the existing approaches of investigating the resulting wave equations are summarized.An application named the zero reflection controller based on the idea of the wave equations is next presented.