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

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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Motor control strategies during bimanual isometric force control among healthy individuals

Adaptive Behavior ◽

10.1177/1059712318822737 ◽

2019 ◽

Vol 27 (2) ◽

pp. 127-136 ◽

Cited By ~ 2

Author(s):

Yan Jin ◽

Minhee Kim ◽

Sejun Oh ◽

BumChul Yoon

Keyword(s):

Young Adults ◽

Motor Control ◽

Control Strategy ◽

Force Control ◽

Isometric Force ◽

Control Strategies ◽

Force Variability ◽

Force Level ◽

Target Force ◽

Motor Synergy

This study aimed to provide a basic description of the motor control strategy during bimanual isometric force control in healthy young adults. Thirty healthy young adults (mean age: 27.4 ± 3.7 years) participated in the study. The subjects were instructed to press both hands simultaneously to match the target force level of 5%, 25%, and 50% bimanual maximum voluntary force using continuous visual feedback. Bimanual motor synergy and bimanual coordination, as well as force asymmetry, force accuracy, and force variability were compared. This study identified the specific motor control strategy of healthy young adults during bimanual isometric force control, indicating that they proportionally increased “good” and “bad” variabilities, resulting in comparable bimanual motor synergy as the target force level increased.

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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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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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Is Power Grasping Contact Continuous or Discrete?

Journal of Applied Biomechanics ◽

10.1123/jab.29.5.554 ◽

2013 ◽

Vol 29 (5) ◽

pp. 554-562 ◽

Cited By ~ 3

Author(s):

Todd C. Pataky ◽

Greg P. Slota ◽

Mark L. Latash ◽

Vladimir M. Zatsiorsky

Keyword(s):

Force Control ◽

Continuous Contact ◽

Local Maxima ◽

External Forces ◽

Power Grasp ◽

Anatomical Constraints ◽

Pushing And Pulling

During power grasp, the number of local force maxima reflects either the central nervous system’s preferential use of particular hand regions, or anatomical constraints, or both. Previously, both bimodal and trimodal force maxima have been hypothesized for power grasp of a cylindrical handle. Here we measure the number of local force maxima, with a resolution of 4.8°, when performing pushing and pulling efforts in the plane perpendicular to the cylinder’s long axis. Twelve participants produced external forces to eight targets. The number of contacts was defined as the number of local maxima exceeding background variance. A minimum of four and a maximum of five discrete contacts were observed in all subjects at the distal phalanges and metacarpal heads. We thus reject previous hypotheses of bimodal or trimodal force control for cylindrical power grasping. Since we presently observed only 4–5 contacts, which is rather low considering the hand’s kinematic flexibility in the flexion plane, we also reject hypotheses of continuous contact, which are inherent to current grasping taxonomy. A modification to current grasping taxonomy is proposed wherein power grasp contains separate branches for continuous and discrete contacts, and where power and precision grasps are distinguished only by grasp manipulability.

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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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