scholarly journals Performance Evaluation of Closed-loop Industrial Applications Over Imperfect Networks

2019 ◽  
pp. 32-38
Author(s):  
Sándor Rácz ◽  
Géza Szabó ◽  
József Pető

5G networks provide technology enablers targeting industrial applications. One key enabler is the Ultra Reliable Low Latency Communication (URLLC). This paper studies the performance impact of network delay on closed-loop control for industrial applications. We investigate the performance of the closed-loop control of an UR5 industrial robot arm assuming fix delay. The goal is to stress the system at the upper limit of the possible network delay. We prove that to achieve the maximum speed, URLLC is a must have.

2019 ◽  
Vol 256 ◽  
pp. 03004 ◽  
Author(s):  
Dong Luo ◽  
Xiaogang Xiong ◽  
Shanhai Jin ◽  
Wei Chen

The quasi-static operations of MEMS mirror are very sensitive to undesired oscillations due to its very low damping. It has been shown that closed-loop control can be superior to reduce those oscillations than open-loop control in the literature. For the closed-loop control, the conventional way of implementing sliding mode control (SMC) algorithm is forward Euler method, which results in numerical chattering in the control input and output. This paper proposes an implicit Euler implementation scheme of super twisting observer and twisting control for a commercial MEMS mirror actuated by an electrostatic staggered vertical comb (SVC) drive structure. The famous super-twisting algorithm is used as an observer and twisting SMC is used as a controller. Both are discretized by an implicit Euler integration method, and their implementation algorithms are provided. Simulations verify that, as compared to traditional sliding mode control implementation, the proposed scheme reduces the chattering both in trajectory tracking output and control input in presence of model uncertainties and external disturbances. The comparison demonstrates the potential applications of the proposed scheme in industrial applications in terms of feasibility and performance.


2020 ◽  
Vol 37 (6) ◽  
pp. 2017-2034
Author(s):  
Yu-Ting L.V. ◽  
Yong Li ◽  
De-Xing Yang ◽  
Zhenhua Bai ◽  
Jinlong Li ◽  
...  

Purpose Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve. Design/methodology/approach A shape model for the CA process is established in this study. Specifically, a virtual shapemeter and closed-loop control system based on the advanced parameter acquisition system and information transmission of CA units are developed in C++ programming language. This system realises real-time dynamic shape display, closed-loop control and shape prediction by collecting raw data of steel coils and parameters during CA. Findings Field test results show that the shape predicted by the virtual shapemeter coincides with the measured shape by over 90 per cent, which fully meets the precision requirement of industrial applications. Originality/value Moreover, shape quality is effectively improved without increasing hardware investments.


1986 ◽  
Vol 30 (1) ◽  
pp. 43-44 ◽  
Author(s):  
George C. Mohr

The Air Force sees a need for a militarized robot, designed to perform flight line maintenance and repair operations during a chemical/biological/radiological attack, or to assist man in space operations such as constructing a space station or performing such tasks as satellite inspection, diagnosis, repair, modification or deactivation. Obviously, these tasks require more than the pre-programmed behavior of an industrial robot. To obtain the high degree of adaptability required, the robot needs either the closed-loop control of a human operator, or a high level “artificial intelligence” capable of emulating human cognitive functions. Robotic telepresence is a novel approach to closed-loop control. By coupling the human operator's visual, tactile, motor and cognitive functions with a remote robot's “head, eyes, and hands,” the human operator is placed effectively “in-the-scene.” With this approach, the natural synergism between the human visual system and hands is exploited to endow the robotic system with human-like capacities to inspect, evaluate, and manipulate. Through robotic telepresence technology, the essential human operator tasks can then be performed in a lethally hazardous environment without exposing the human operator directly.


2012 ◽  
Vol 220 (1) ◽  
pp. 3-9 ◽  
Author(s):  
Sandra Sülzenbrück

For the effective use of modern tools, the inherent visuo-motor transformation needs to be mastered. The successful adjustment to and learning of these transformations crucially depends on practice conditions, particularly on the type of visual feedback during practice. Here, a review about empirical research exploring the influence of continuous and terminal visual feedback during practice on the mastery of visuo-motor transformations is provided. Two studies investigating the impact of the type of visual feedback on either direction-dependent visuo-motor gains or the complex visuo-motor transformation of a virtual two-sided lever are presented in more detail. The findings of these studies indicate that the continuous availability of visual feedback supports performance when closed-loop control is possible, but impairs performance when visual input is no longer available. Different approaches to explain these performance differences due to the type of visual feedback during practice are considered. For example, these differences could reflect a process of re-optimization of motor planning in a novel environment or represent effects of the specificity of practice. Furthermore, differences in the allocation of attention during movements with terminal and continuous visual feedback could account for the observed differences.


Sign in / Sign up

Export Citation Format

Share Document