scholarly journals Haptics control of an arm exoskeleton for virtual reality using PSO-based fixed structure H∞ control

2019 ◽  
Vol 16 (3) ◽  
pp. 172988141984919 ◽  
Author(s):  
Chaiyaporn Silawatchananai ◽  
Manukid Parnichkun

This article proposes a robust haptics control algorithm for an arm exoskeleton in virtual reality application that guarantees the robustness of the force displaying performance. The developed arm exoskeleton allows the user to sense the profile of virtual objects through joints at wrist, elbow, and shoulder. Forces exerted by the user are directly measured by load cells attached to the links, which are used to determine the corresponding velocity command based on virtual impedance. Due to the imperfection of modeling and the measurement noises from load cells and encoder quantization, the force displaying performance of the device tends to degrade with increasing oscillation, causing permanent damages to the device and user. To solve this problem, a Particle swarm optimization (PSO)-based fixed structure H∞ controller is proposed to control the developed arm exoskeleton. The control performance of the proposed controller is evaluated by both simulation and experiment. The results show that the proposed controller can achieve better tracking performance in comparison with proportional–integral–derivative controller in terms of less oscillation and fast response.

2012 ◽  
Vol 466-467 ◽  
pp. 981-985 ◽  
Author(s):  
Xin Yun Qiu ◽  
Yuan Gao

An adaptive PID controller based on single neuron is proposed. The properties, control algorithm, parameters tuning, the control law and the application condition of the controller are studied in the paper. To satisfy the properties of the requirements of the control system in an electromotor group, such as a broad dynamic changing range, a fast response, a little overshoot and time-variable parameter, a new-type self-optimizing PID controller based on artificial neural networks is proposed and studied. It is verified that the controller has few adjustable parameters and excellent robust performance. The results of simulation and experiment prove that the controller is superior to the traditional PID controller.


2014 ◽  
Vol 6 ◽  
pp. 203793 ◽  
Author(s):  
Changhao Piao ◽  
Chao Jiang ◽  
Hongtao Qiao ◽  
Chongdu Cho ◽  
Sheng Lu

The fast response, high efficiency, and good reliability are very important characteristics to electric vehicles (EVs) dc/dc converters. Two-stage dc-dc converter is a kind of dc-dc topologies that can offer those characteristics to EVs. Presently, nonlinear control is an active area of research in the field of the control algorithm of dc-dc converters. However, very few papers research on two-stage converter for EVs. In this paper, a fixed switching frequency sliding mode (FSFSM) controller and double-integral sliding mode (DISM) controller for two-stage dc-dc converter are proposed. And a conventional linear control (lag) is chosen as the comparison. The performances of the proposed FSFSM controller are compared with those obtained by the lag controller. In consequence, the satisfactory simulation and experiment results show that the FSFSM controller is capable of offering good large-signal operations with fast dynamical responses to the converter. At last, some other simulation results are presented to prove that the DISM controller is a promising method for the converter to eliminate the steady-state error.


2014 ◽  
Vol 685 ◽  
pp. 368-372 ◽  
Author(s):  
Hao Zhang ◽  
Ya Jie Zhang ◽  
Yan Gu Zhang

In this study, we presented a boiler combustion robust control method under load changes based on the least squares support vector machine, PID parameters are on-line adjusted and identified by LSSVM, optimum control output is obtained. The simulation result shows control performance of the intelligent control algorithm is superior to traditional control algorithm and fuzzy PID control algorithm, the study provides a new control method for strong non-linear boiler combustion control system.


Author(s):  
Abdulsamed Tabak

Purpose The purpose of this paper is to improve transient response and dynamic performance of automatic voltage regulator (AVR). Design/methodology/approach This paper proposes a novel fractional order proportional–integral–derivative plus derivative (PIλDµDµ2) controller called FOPIDD for AVR system. The FOPIDD controller has seven optimization parameters and the equilibrium optimizer algorithm is used for tuning of controller parameters. The utilized objective function is widely preferred in AVR systems and consists of transient response characteristics. Findings In this study, results of AVR system controlled by FOPIDD is compared with results of proportional–integral–derivative (PID), proportional–integral–derivative acceleration, PID plus second order derivative and fractional order PID controllers. FOPIDD outperforms compared controllers in terms of transient response criteria such as settling time, rise time and overshoot. Then, the frequency domain analysis is performed for the AVR system with FOPIDD controller, and the results are found satisfactory. In addition, robustness test is realized for evaluating performance of FOPIDD controller in perturbed system parameters. In robustness test, FOPIDD controller shows superior control performance. Originality/value The FOPIDD controller is introduced for the first time to improve the control performance of the AVR system. The proposed FOPIDD controller has shown superior performance on AVR systems because of having seven optimization parameters and being fractional order based.


2018 ◽  
Vol 10 (12) ◽  
pp. 168781401881536 ◽  
Author(s):  
Yong Zhou ◽  
Xiaogang Zhou

The reliable and repeatable experimental ground testing of aircraft actuator is an essential phase before flight testing. It is not an easy task to simulate the alternating aerodynamic forces on actuators reasonably and accurately in a laboratory. In this article, an experimental test bench is designed to simulate the aerodynamic forces by a hydraulic actuator, which replicates the operating conditions that the actuator will encounter in service. In order to improve the force control performance, a feed-forward compensator and a fuzzy proportional–integral–derivative controller are designed. Both simulation and experimental results show that the designed method can improve the control performance.


2021 ◽  
pp. 107754632110501
Author(s):  
Ji-Won Lee ◽  
Nguyen Xuan-Mung ◽  
Ngoc Phi Nguyen ◽  
Sung Kyung Hong

In recent years, the boom of the quadcopter industry resulted in a broad range of real-world applications which highlighted the urgent need to improve quadcopter control quality. Typically, external disturbances, such as wind, parameter uncertainties caused by payload variations, or the ground effect, can severely degrade the quadcopter’s altitude control performance. Meanwhile, widely used controllers like the proportional-integral-derivative control cannot guarantee control performance when the system is critically affected by factors that exhibit a high degree of variability with time. In this paper, an adaptive control algorithm is proposed to improve quadcopter altitude tracking performance in the presence of both the ground effect and a time-varying payload. First, we derive an adaptive altitude control algorithm using the sliding mode control technique to account for these uncertainties in the quadcopter dynamics model. Second, we apply Lyapunov theory to analyze the stability of the closed-loop system. Finally, we conduct several numerical simulations and experiments to validate the effectiveness of the proposed method.


Energies ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2915 ◽  
Author(s):  
Sang Min Park ◽  
Eunsu Jang ◽  
Dongmyoung Joo ◽  
Byoung Kuk Lee

Typical domestic induction cooktops can only heat ferromagnetic pots/vessels. However, to increase the availability and marketability of induction heating (IH) cooktop products, heating techniques for all types of metallic pots (i.e., created from metals such as aluminum, copper, and stainless steel) are required. To satisfy the requirements of induction cooktops, this paper proposes the design of an all-metal domestic IH system that can heat any type of metallic pot while considering the temperature variation of the working-coil. A control algorithm using a power curve-fitting method (CFM) is presented to quickly respond to load parameter variations in the IH. In addition, the CFM control algorithm is established to compensate for the power reference value by reflecting the increase in the working-coil temperature during the heating of the non-ferromagnetic pot. To evaluate the performance of the proposed system, the control algorithm strategy and experimental results based on a 3.2 kW all-metal IH cooktop are presented.


2017 ◽  
Vol 79 (6) ◽  
Author(s):  
Andi Adriansyah ◽  
Shamsudin H. M. Amin ◽  
Anwar Minarso ◽  
Eko Ihsanto

The rapid development of microprocessor, electrical, sensors and advanced control technology make a quadrotor fast expansion. Unfortunately, a quadrotor is unstable and impossible to fly in fully open loop system. PID controller is one of methodology that has been proposed to control the flight control system. Unfortunately, adjustment of PID parameters for robust control performance is not easy and still problems. The paper proposed a flight controller system based on a PID controller. The PID parameters are tuned automatically using Particle Swarm Optimization (PSO). Objective of this method is to improve the flight control system performance. Several experiments have been performed. According to these experiments the proposed system able to generate optimal and reliable PID parameters for robust flight controller. The system also has 41.57 % improvement in settling time response.


2014 ◽  
Vol 525 ◽  
pp. 583-587
Author(s):  
Bing Tu ◽  
Wei Zhang ◽  
Teng Xi Zhan

This paper presented a excitation liquid-cooled retarder control system based on a microprocessor MC9SXS128. In order to achieve the constant speed, It used PWM to adjust the output current of excitation liquid-cooled retarder. It analyzed and calculated the inductance value in PWM output circuit and also analyzed the excitation liquid-cooled retarder control systematical mathematical model . It divided the brake stalls based on the current flowing through the field coil. by adding the PID closed-loop control system, the retarder could quickly reach the set speed. It tested the PID control algorithm at the experiments in retarder drum test rig and the results show that the control algorithm has good control performance to meet the application requirements.


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