Passive force control of multimodal astronaut training robot

For the purpose of solving the problem of astronaut training in weightlessness environment, this article proposes a multimodal astronaut training robot to enable astronauts to perform running, bench press and deep squat training in the weightless environment, so as to help them mitigate the adverse effects brought by the space adaptation syndrome. Taking the modularized wire driving unit as the research object, the dynamic model of the passive force servo system was established; and the passive force control strategy was designed. The experimental results show that the system is of good stability, high steady-state accuracy, and excellent dynamic quality after correction. When the given signal frequency is 10 Hz, the system phase lag is about 9°, and the loading error is about 5%. The passive force servo control strategy can effectively reduce the surplus force. When the speed disturbance frequency of carrying unit is within 3 Hz, the elimination rate of the surplus force can reach 90%.

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Hybrid active/passive force control strategy for grinding marks suppression and profile accuracy enhancement in robotic belt grinding of turbine blade

Robotics and Computer-Integrated Manufacturing ◽

10.1016/j.rcim.2020.102047 ◽

2021 ◽

Vol 67 ◽

pp. 102047 ◽

Cited By ~ 2

Author(s):

Xiaohu Xu ◽

Wei Chen ◽

Dahu Zhu ◽

Sijie Yan ◽

Han Ding

Keyword(s):

Turbine Blade ◽

Control Strategy ◽

Force Control ◽

Passive Force ◽

Belt Grinding ◽

Accuracy Enhancement ◽

Robotic Belt Grinding ◽

Profile Accuracy

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Constant force control for aluminum wheel hub grinding based on ESO + backstepping

Industrial Robot the international journal of robotics research and application ◽

10.1108/ir-09-2021-0193 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Shijie Dai ◽

Yufeng Zhao ◽

Wenbin Ji ◽

Jiaheng Mu ◽

Fengbao Hu

Keyword(s):

Control Strategy ◽

Force Control ◽

Control Method ◽

Response Speed ◽

Backstepping Control ◽

Constant Force ◽

Content Type ◽

Disturbance Rejection Control ◽

The Stability ◽

Differential Control

Purpose This paper aims to present a control method to realize the constant force grinding of automobile wheel hub. Design/methodology/approach A constant force control strategy combined by extended state observer (ESO) and backstepping control is proposed. ESO is used to estimate the total disturbance to improve the anti-interference and stability of the system and Backstepping control is used to improve the response speed of the system. Findings The simulation and grinding experimental results show that, compared with the proportional integral differential control and active disturbance rejection control, the designed controller can improve the dynamic response performance and anti-interference ability of the system and can quickly track the expected force and improve the grinding quality of the hub surface. Originality/value The main contribution of this paper lies in the proposed of a new constant force control strategy, which significantly improved the stability and precision of grinding force.

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Tire Force Control Strategy for Semi Active Magnetorheological Damper Suspension System Using Quarter Heavy Vehicle Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.789-790.957 ◽

2015 ◽

Vol 789-790 ◽

pp. 957-961

Author(s):

Syabillah Sulaiman ◽

Pakharuddin Mohd Samin ◽

Hishamuddin Jamaluddin ◽

Roslan Abd Rahman ◽

Saiful Anuar Abu Bakar

Keyword(s):

Simulation Model ◽

Control Strategy ◽

Force Control ◽

Mr Damper ◽

Magnetorheological Damper ◽

Vehicle Suspension ◽

Heavy Vehicle ◽

Vehicle Model ◽

Tire Force ◽

Simulation Results

This paper proposed semi active controller scheme for magnetorheological (MR) damper of a heavy vehicle suspension known as Tire Force Control (TFC). A reported algorithm in the literature to reduce tire force is Groundhook (GRD). Thus, the objective of this paper is to investigate the effectiveness of the proposed TFC algorithm compared to GRD. These algorithms are applied to a quarter heavy vehicle models, where the objective of the proposed controller is to reduce unsprung force (tire force). The simulation model was developed and simulated using MATLAB Simulink software. The use of semi active MR damper using TFC is analytically studied. Ride test was conducted at three different speeds and three bump heights, and the simulation results of TFC and GRD are compared and analysed. The results showed that the proposed controller is able to reduced tire force significantly compared to GRD control strategy.

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Force Control Strategy of Five-Digit Precision Grasping With Aligned and Unaligned Configurations

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/00187208211040914 ◽

2022 ◽

pp. 001872082110409

Author(s):

Po-Tsun Chen ◽

Hsiu-Yun Hsu ◽

You-Hua Su ◽

Chien-Ju Lin ◽

Hsiao-Feng Chieh ◽

...

Keyword(s):

Control Strategy ◽

Force Control ◽

Task Type ◽

Applied Force ◽

Force Variability ◽

Force Transducers ◽

Task Requirements ◽

Power Grasp ◽

Precision Grasping ◽

Large Moment

Objective To investigate the digit force control during a five-digit precision grasp in aligned (AG) and unaligned grasping (UG) configurations. Background The effects of various cylindrical handles for tools on power grasp performance have been previously investigated. However, there is little information on force control strategy of precision grasp to fit various grasping configurations. Method Twenty healthy young adults were recruited to perform a lift-hold-lower task. The AG and UG configurations on a cylindrical simulator with force transducers were adjusted for each individual. The applied force and moment, the force variability during holding, and force correlations between thumb and each finger were measured. Result No differences in applied force, force correlation, repeatability, and variability were found between configurations. However, the moments applied in UG were significantly larger than those in AG. Conclusion The force control during precision grasp did not change significantly across AG and UG except for the digit moment. The simulator is controlled efficiently with large moment during UG, which is thus the optimal configuration for precision grasping with a cylindrical handle. Further research should consider the effects of task type and handle design on force control, especially for individuals with hand disorders. Application To design the handle of specific tool, one should consider the appropriate configuration according to the task requirements of precision grasping to reduce the risk of accumulating extra loads on digits with a cylindrical handle.

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Effects of aging on motor control strategies during bimanual isometric force control

Adaptive Behavior ◽

10.1177/1059712319849896 ◽

2019 ◽

Vol 27 (4) ◽

pp. 267-275

Author(s):

Yan Jin ◽

JiWon Seong ◽

YoungChae Cho ◽

BumChul Yoon

Keyword(s):

Older Adults ◽

Motor Control ◽

Control Strategy ◽

Force Control ◽

Isometric Force ◽

Control Strategies ◽

Force Variability ◽

Dual Tasking ◽

Effects Of Aging ◽

Force Accuracy

Aging-induced degeneration of the neuromuscular system would result in deteriorated complex muscle force coordination and difficulty in executing daily activities that require both hands. The aim of this study was to provide a basic description of how aging and dual-task activity would affect the motor control strategy during bimanual isometric force control in healthy adults. In total, 17 young adults (aged 25.1 ± 2.4 years) and 14 older adults (aged 72.6 ± 3.4 years) participated in the study. The subjects were instructed to press both hands simultaneously to match the 1 Hz sine curve force under two conditions (with or without calculation) with continuous visual feedback. Differences in bimanual motor synergy, bimanual coordination, force accuracy, force variability, and calculation speed were compared. This study found that the specific motor control strategy of older adults involved a decreased bimanual force control ability with both increased VUCM and VORT, and was not influenced by dual tasking. These findings might have implications for establishing interventions for aging-induced hand force control deficits.

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Comparative Study on Several PQ and V/f Controller Models in Micro-Grid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1044-1045.738 ◽

2014 ◽

Vol 1044-1045 ◽

pp. 738-742

Author(s):

Wen Xia You ◽

Zi Heng Zhou ◽

Jun Xiao Chang ◽

Gang Sun

Keyword(s):

Comparative Study ◽

Control Strategy ◽

Matlab Simulink ◽

Micro Grid ◽

Simulation Results ◽

Dynamic Quality

Many references have been focused on PQ controllers and V/f controllers, but there are some models with different components share the same control strategy. These models have different simulation results of their own. In this paper, two ordinary PQ controllers and two ordinary V/f controllers have been chosen to study the simulation results of them by Matlab/Simulink. By analyzing voltage and current waveforms of load, it has been decided which PQ controller has result which contains less unbalanced current and less harmonics, and so it is with the V/f controllers. Then the chosen controllers have been applied to an example of Master-slave control strategy for a simple micro-grid, which furthermore proves the dynamic quality of the chosen models. In this way, the problem to choose better models is solved.

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Study of Dominant Performance Characteristics in Robot Transmissions

Journal of Mechanical Design ◽

10.1115/1.2919214 ◽

1993 ◽

Vol 115 (3) ◽

pp. 472-482 ◽

Cited By ~ 22

Author(s):

H. Schempf ◽

D. R. Yoerger

Keyword(s):

Force Control ◽

Closed Loop ◽

Stability Margin ◽

Viscous Friction ◽

Open Loop ◽

Phase Lag ◽

Stability Margins ◽

Loop Bandwidth ◽

Hard Contact ◽

Following Error

Six different transmission types suitable for robotic manipulators were compared in an experimental and theoretical study. Single-degree-of-freedom mechanisms based on the different transmissions were evaluated in terms of force control performance, achievable bandwidth, and stability properties in hard contact tasks. Transmission types considered were (1) cable reducer, (2) harmonic drive, (3) cycloidal disk reducer, (4) cycloidal cam reducer, (5) ball reducer, and (6) planetary/cycloidal gear head. Open loop torque following error, attenuation and phase lag, and closed loop bandwidth and stability margin were found to be severely dominated by levels of inertia, stiffness distribution and variability, stiction, coulomb and viscous friction, and ripple torque. These aspects were quantified and shown to vary widely among all transmissions tested. The degree of nonlinearity inherent in each transmission affected its open and closed loop behavior directly, and limited the effectiveness of controller compensation schemes. Simple transmission models based on carefully measured transmission characteristics are shown to predict stability margins and achievable force-control bandwidths in hard contact to within a 5 to 15 percent error margin.

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Adaptive Position Tracking System and Force Control Strategy for Mobile Robot Manipulators Using Fuzzy Wavelet Neural Networks

Journal of Intelligent & Robotic Systems ◽

10.1007/s10846-013-0006-5 ◽

2014 ◽

Vol 79 (2) ◽

pp. 175-195 ◽

Cited By ~ 8

Author(s):

Mai Thang Long ◽

Wang Yao Nan

Keyword(s):

Neural Networks ◽

Mobile Robot ◽

Control Strategy ◽

Force Control ◽

Robot Manipulators ◽

Tracking System ◽

Position Tracking ◽

Wavelet Neural Networks ◽

Fuzzy Wavelet Neural Networks ◽

Mobile Robot Manipulators

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Analysis of Hand-Arm Coordinate Motion on Constraint Tasks

Journal of Robotics and Mechatronics ◽

10.20965/jrm.1991.p0497 ◽

1991 ◽

Vol 3 (6) ◽

pp. 497-505

Author(s):

Shigeki Sugano ◽

◽

Hideyo Namimoto ◽

Ichiro Kato

Keyword(s):

Control Strategy ◽

Force Control ◽

Degrees Of Freedom ◽

Control Mechanism ◽

Human Motion ◽

Degree Of Freedom ◽

Human Hand ◽

Human Motion Analysis ◽

Manipulator Control ◽

Arm Coordination

This research was conducted to study the control strategy of manipulator based on clarifying the force control mechanism of the human hand-arm by analyzing human constraint tasks with respect to biomechanism. In this paper; we describe an investigation of hand-arm function share. In addition, we apply hand-arm coordination to manipulator control using experimental results of analyzing the human tasks of moving bead balls on a shaft, which is an example of a constraint task with one degree of freedom (d.o.f.). In the human motion analysis, 6 axes of force on the task object are measured and compared in the case of constraining the hands degree of freedom and making hand free as well as in the case of with or without forced displacement along the translational direction during motion. As a result, we found that human work was performed smoothly through absorption of rotational force using hand d.o.f. and translational force using arm d.o.f. Also, it was found that there are the direction of motion and the posture easily absorbable translational force. Finally, we propose to apply the human hand-arm coordination compliance control strategy setting translational compliance by arms and rotational compliance by hands, to manipulator with more than 7 degrees of freedom. Thus, the setting of optional compliance applicable to circumstance and the resulting force control due to this become possible.

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