Robotic manipulation with large time delay on visual feedback systems

Abstract This paper is concerned with a linear time-delay circuit and its feedback control. We use electronic components such as resistors and capacitors to realize a linear time-delay system. The time-delays are generated by operational amplifiers and single-chip microcomputers. Based on the actual data measured by the oscilloscope, the parameters of the system are estimated using the least square method. Then a comparison study between the waveform image measured by the oscilloscope and the numerical simulation obtained by MATLAB verifies the effectiveness of the parameters estimations of the circuit system. Furthermore, the circuit system is unstable with a large time-delay, a feedback controller is designed to stabilize the circuit system using the optimization method in the literature. Finally, the experimental results in the linear time-delay circuit show the effectiveness of the optimization method.

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A Design Method for Modified Smith Predictors for Non-Minimum-Phase Time-Delay Plants with Multiple Feedback-Connected Time-Delays

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.36.253 ◽

2010 ◽

Vol 36 ◽

pp. 253-262 ◽

Cited By ~ 1

Author(s):

Iwanori Murakami ◽

Nghia Thi Mai ◽

Kou Yamada ◽

Takaaki Hagiwara ◽

Yoshinori Ando ◽

...

Keyword(s):

Steady State ◽

Time Delay ◽

Time Delays ◽

Large Time ◽

Design Method ◽

Smith Predictor ◽

Minimum Phase ◽

Effective Time ◽

Phase Time ◽

Step Disturbance

In this paper, we examine a design method for modified Smith predictors for non-minimum-phase time-delay plants with multiple feedback-connected time-delays. The Smith predictor is proposed by Smith to overcome time-delay and known as an effective time-delay compensator for a plant with large time-delay. The Smith predictor by Smith cannot be used for plants having an integral mode, because a step disturbance will result in a steady state error. Several papers considered the problem to design modified Smith predictors for unstable plants. However, no paper examines a design method for modified Smith predictors for non-minimum-phase time-delay plants with multiple feedback-connected time-delays. In this paper, we examine a design method for modified Smith predictors for non-minimum-phase time-delay plants with multiple feedback-connected time-delays.

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Modeling head tracking of visual targets

Journal of Vestibular Research ◽

10.3233/ves-2002-12103 ◽

2002 ◽

Vol 12 (1) ◽

pp. 25-33

Author(s):

K.J. Chen ◽

E.A. Keshner ◽

B.W. Peterson ◽

T.C. Hain

Keyword(s):

Control System ◽

Visual Feedback ◽

Human Head ◽

Feedback System ◽

Optimization Methods ◽

Head Tracking ◽

Feedback Systems ◽

Control Gain ◽

Head Control ◽

Visual Targets

Control of the head involves somatosensory, vestibular, and visual feedback. The dynamics of these three feedback systems must be identified in order to gain a greater understanding of the head control system. We have completed one step in the development of a head control model by identifying the dynamics of the visual feedback system. A mathematical model of human head tracking of visual targets in the horizontal plane was fit to experimental data from seven subjects performing a visual head tracking task. The model incorporates components based on the underlying physiology of the head control system. Using optimization methods, we were able to identify neural processing delay, visual control gain, and neck viscosity parameters in each experimental subject.

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