scholarly journals An Adaptive Mechatronic Exoskeleton for Force-Controlled Finger Rehabilitation

2021 ◽  
Vol 8 ◽  
Author(s):  
Thomas Dickmann ◽  
Nikolas J. Wilhelm ◽  
Claudio Glowalla ◽  
Sami Haddadin ◽  
Patrick van der Smagt ◽  
...  
Keyword(s):  
Force Control ◽  
Healthy Subjects ◽  
Angular Position ◽  
Kinematic Structure ◽  
Joint Torques ◽  
Actuation Force ◽  
Subject Specific ◽  
Safety Features ◽  
And Control ◽  
Accurate Quantification

This paper presents a novel mechatronic exoskeleton architecture for finger rehabilitation. The system consists of an underactuated kinematic structure that enables the exoskeleton to act as an adaptive finger stimulator. The exoskeleton has sensors for motion detection and control. The proposed architecture offers three main advantages. First, the exoskeleton enables accurate quantification of subject-specific finger dynamics. The configuration of the exoskeleton can be fully reconstructed using measurements from three angular position sensors placed on the kinematic structure. In addition, the actuation force acting on the exoskeleton is recorded. Thus, the range of motion (ROM) and the force and torque trajectories of each finger joint can be determined. Second, the adaptive kinematic structure allows the patient to perform various functional tasks. The force control of the exoskeleton acts like a safeguard and limits the maximum possible joint torques during finger movement. Last, the system is compact, lightweight and does not require extensive peripherals. Due to its safety features, it is easy to use in the home. Applicability was tested in three healthy subjects.

scholarly journals Torque control of underactuated tendon-driven fingers

2011 ◽  
Vol 2 (1) ◽  
pp. 83-90 ◽  
Author(s):  
M. E. Abdallah ◽  
C. W. Wampler
Keyword(s):  
Force Control ◽  
Position Control ◽  
International Workshop ◽  
Torque Control ◽  
Joint Torques ◽  
Effective Performance ◽  
Joint Limits ◽  
And Control ◽  
Finger Posture ◽  
Humanoid Hand

Abstract. Given an underactuated tendon-driven finger, the finger posture is underdetermined and can move freely ("flop") in a region of slack tendons. This work shows that such an underactuated finger can be operated in tendon force control (rather than position control) with effective performance. The force control eliminates the indeterminate slack while commanding a parameterized space of desired torques. The torque will either push the finger to the joint limits or wrap around an external object with variable torque – behavior that is sufficient for primarily gripping fingers. In addition, introducing asymmetric joint radii to the design allows the finger to command an expanded range of joint torques and to scan an expanded set of external surfaces. This study is motivated by the design and control of the secondary fingers of the NASA-GM R2 humanoid hand. This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010), 19 August 2010, Montréal, Canada.

scholarly journals Evaluation of the phagocytic activity of peripheral blood monocytes of patients with Jorge Lobo's disease

2004 ◽  
Vol 37 (2) ◽  
pp. 165-168 ◽  
Author(s):  
Fátima Regina Vilani-Moreno ◽  
Luciana Moreira Silva ◽  
Diltor Vladimir Araújo Opromolla
Keyword(s):  
Incubation Time ◽  
Peripheral Blood ◽  
Phagocytic Activity ◽  
Healthy Subjects ◽  
Mononuclear Cells ◽  
Blood Monocytes ◽  
Peripheral Blood Monocytes ◽  
Significant Difference ◽  
Host Parasite ◽  
And Control

Studies on host-parasite interaction in Jorge Lobo's disease are scarce, with no report in the literature on the phagocytosis of Lacazia loboi by phagocytic mononuclear cells. Thus, the objective of the present study was to assess the phagocytic activity of blood monocytes in the presence of L. loboi in patients with the disease and in healthy subjects (controls) over 3 and 24 hours of incubation. Statistical analyses of the results showed no significant difference in percent phagocytosis of the fungus between patient and control monocytes. With respect to incubation time, however, there was a significant difference, in that percent phagocytosis was higher at 3 hours than at 24 hours (p <0.01). These results suggest that monocytes from patients with the mycosis are able to phagocyte the fungus, as also observed in control individuals.

scholarly journals THE CORRELATION OF THE CATEGORIES OF “QUALITY” AND “SAFETY” OF PRODUCTS

2019 ◽  
pp. 74-78
Author(s):  
T.V. Malanchuk ◽  
E.A. Zaitsev
Keyword(s):  
Civil Rights ◽  
Legal Regulation ◽  
Poor Quality ◽  
Product Safety ◽  
Legal Rights ◽  
Safety Issues ◽  
State Supervision ◽  
Safety Features ◽  
And Control

The article analyzes the complex state of the modern legislative regulation of quality and product safety issues in the context of ensuring consumers’ rights to the proper quality of goods (works, services). It is stated that in view of the variety of different properties that make up the notion of quality, the most important are the defects, which are capable of damaging the life, health, or property of the consumer, that is, the defects, which indicate that the goods are dangerous. The safety of goods works, and services as a legal category are of particular importance and is one of the functions of the state to ensure public safety. State measures of influence on manufacturers and sellers of goods, persons who perform work and provide services should be aimed at ensuring the protection of fundamental civil rights. In most cases, these are imperative requirements for safety, which are approved by special legal acts, as well as measures of state supervision and control to ensure the safety of manufactured goods, works, and services. The legislator, when defining security, uses the term “safety of goods (works, services)”, but it would be advisable to carry out graduation of these concepts since the safety of goods is a state of goods that allows it to be sold, used, stored, transported, disposed of without harm for life, health, the property of the consumer and the environment in normal conditions, and the safety of works and services is the quality of protection of the legal rights of the consumer in carrying out the activities of persons who perform work and provide services, danger to life, health, the property should not manifest itself either in their implementation and providing or later. It is noted that quality requirements should be made mandatory when designing production specifications. It is stated that in order to ensure the effectiveness of legal regulation, the safety of a product, work, or service must be considered as a full-fledged property within the legal notion of quality. It is concluded that product safety is an integral feature of any product, work, and service, acting as an integral element of the quality category. Lack of safety features indicates that the product is of poor quality. Keywords: quality, safety, proper quality, improper quality, specifications, consumers.

Increased NOX1 and DOUX2 Expression in the Colonic Mucosa of Patients with Chronic Functional Constipation

2021 ◽  
Author(s):  
Xiuqin Wei ◽  
Chunbo Kang ◽  
Lei Gao ◽  
Mengqiao Zhang ◽  
Mei Xue ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Healthy Subjects ◽  
Mrna Level ◽  
Functional Constipation ◽  
Inflammatory Cells ◽  
Histological Structure ◽  
Mrna Levels ◽  
Significant Difference ◽  
And Control ◽  
Colonic Biopsies

Abstract Aim To determine whether oxidative stress and inflammation are associated with constipation by examining the expression of the main producers of reactive oxygen species, NADPH oxidases, and pro-inflammatory cytokines in the colon of patients with chronic functional constipation. Methods The colonic biopsies were collected from 32 patients with chronic functional constipation and 30 healthy subjects who underwent colonoscopy. Colonic mucosal histology was observed. IL-1β, IL-6, IL-8 mRNA, and four members of NADPH oxidase (NOX1, NOX2, DOUX2 and NOX4) protein and mRNA were assessed by immunohistochemistry, western blotting and RT-PCR. Results The tissues from both patients and healthy subjects showed normal histological structure without increase of inflammatory cells. NOX1 protein and mRNA levels were significantly increased compared to controls (P<0.05). DOUX2 protein, but not mRNA, was increased by twofold compared to controls (P<0.05). The levels of NOX2 and NOX4 protein and mRNA demonstrated no significant difference between patients and control subjects. The levels of IL-1β and IL-6 mRNA were significantly higher in constipation patients (P<0.05), while IL-8 mRNA level was no different between the two groups. Conclusion NADPH oxidase and pro-inflammatory cytokine might be involved in the pathogeneses of chronic functional constipation.

Catastrophe Analysis of Planar Three-Spring Systems

1998 ◽  
Author(s):  
J. P. Yin ◽  
D. Marsh ◽  
J. Duffy
Keyword(s):  
Contact Force ◽  
Force Control ◽  
Energy Function ◽  
System A ◽  
Spring System ◽  
Spring Mechanism ◽  
And Control ◽  
Control Tool ◽  
Contact Force Control

Abstract A special planar three-spring mechanism is proposed for contact force control. An energy function is defined to describe the behavior of this kind of mechanism. It can be used to perform the catastrophe analysis of this mechanism. The analysis result can be used as a design and control tool. By comparing the three-spring system and a two-spring system, we found the three-spring mechanism has better stability than the two-spring system. A three-spring mechanism which can be used to control a general contact force in a plane is also analyzed.

Predictive value of the neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, platelet-to-neutrophil ratio, and neutrophil-to-monocyte ratio in lupus nephritis

Lupus ◽  
2020 ◽  
Vol 29 (9) ◽  
pp. 1031-1039
Author(s):  
Peng Liu ◽  
Peiyuan Li ◽  
Zhong Peng ◽  
Yazhou Xiang ◽  
Chenqi Xia ◽  
...  
Keyword(s):  
Lupus Nephritis ◽  
Healthy Subjects ◽  
Area Under The Curve ◽  
Neutrophil To Lymphocyte Ratio ◽  
Control Group ◽  
Receiver Operating Characteristic Curves ◽  
Lymphocyte Ratio ◽  
And Control ◽  
First Time

Objective To evaluate the role of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-neutrophil ratio (PNR), platelet-to-monocyte ratio (PMR), and neutrophil-to-monocyte ratio (NMR) as predictors for lupus nephritis (LN) patients without infection or as biomarkers for distinguishing between infection or flare with LN patients. Methods LN patients were divided into three groups: LN without infection, LN with infection, and LN with flare. A total of 57 healthy subjects were enrolled as controls. The differentiation was analyzed between LN without infection and control group, and LN with infection and LN with flare. Correlations among variables were assessed in the LN group without infection. Receiver operating characteristic curves were constructed in two comparable groups. Results NLR, PLR, and MLR were increased significantly in the LN group without infection as compared with those in healthy controls. NLR (area under the curve (AUC): 0.75) and MLR (AUC: 0.79) were useful for distinguishing between LN patients without infection and healthy subjects. In differentiating LN patients without infection from the controls, optimal cutoffs of NLR and MLR were 3.43 (sensitivity: 45.6%, specificity: 96.5%, and overall accuracy: 68.8%) and 0.24 (sensitivity: 75.0%, specificity: 73.7%, and overall accuracy: 73.6%), respectively. In addition, NLR ( r = 0.322, p = 0.011) and PLR ( r = 0.283, p = 0.026) were positively correlated with CRP. Importantly, NLR and NMR were increased while PNR was decreased in the LN group with infection in comparison with those in the LN group with flare. NLR (AUC: 0.80), NMR (AUC: 0.78), and PNR (AUC: 0.74) were useful in differentiating LN patients with infection and flare, and their optimal cutoffs were 4.02 (sensitivity: 82.6%, specificity: 69.6%, and overall accuracy: 75.5%), 12.19 (sensitivity: 80.4%, specificity: 73.9%, and overall accuracy: 77.5%), and 28.26 (sensitivity: 65.2%, specificity: 76.8%, and overall accuracy: 71.6%), respectively. Conclusions We demonstrated, for the first time, that MLR or NMR had the best accuracy in differentiating LN patients without infection from healthy subjects, or differentiating infection from flare in LN patients, respectively. Our results implied that NLR, MLR, PNR, and NMR may be useful biomarkers in predicting LN.

Gain-Scheduled Control Approach by Logarithm Transformation for Electrical Vehicle Traction Force Control

2014 ◽  
Vol 619 ◽  
pp. 283-287
Author(s):  
Jieh Shian Young ◽  
Yu Bang Lin ◽  
Kuan Jie Chen ◽  
Po Ting Chen
Keyword(s):  
Force Control ◽  
Traction Force ◽  
Road Surface ◽  
Real Situation ◽  
Slip Ratio ◽  
Control Approach ◽  
Electrical Vehicle ◽  
And Control ◽  
Gain Scheduled

This paper proposes an approach by logarithm to evaluating the electrical vehicle traction force control directly instead of the slip ratio measurements. Utilizing the built character database of the driven motor, or so-called current-RPM-torque database, a gain-scheduled approach by logarithm transformation is developed to provide the appropriate traction force while one traction wheel of the vehicle is traveling into different road surface. An illustrated simulation with a scenario close to real situation is also given to show the feasibility to evaluate and control the traction force through the database of the motor.

Optimal Control Design of a Bimorph Optical Beam Deflector

2001 ◽  
Author(s):  
Chang-Po Chao ◽  
Jeng-Sheng Huang ◽  
Ching-Lung Ou Yung ◽  
Rong-Fong Fung
Keyword(s):  
Optimal Control ◽  
Position Control ◽  
Angular Position ◽  
Control Design ◽  
Element Model ◽  
Optical Beam ◽  
Optimal Feedback Control ◽  
Central Position ◽  
Control Effort ◽  
And Control

Abstract The optical beam deflector is composed of two piezoelectric layers, one sandwiched brass layer in the middle with both ends clamped and a mirror attached to the upper surface of the top piezoelectric layer in the central position. This structure is designed to deflect the mirror to a certain angular position by applying external voltage supply to piezo-layers. This study proposes an optimal angular position control scheme of the attached mirror. The governing partial differential equations are first derived for the ensuing analysis and control design, which is followed by the establishment of finite element model in ten nodes specified at some longitudinal points of the optical beam deflector. In order to achieve a faster convergent rate for the deflector to reach the desired angular position, the optimal control of LQ regulator with final states fixed is employed to explore the possibility of shorter transient response and less cost of control effort and states. The optimal feedback control is obtained based on solving a dynamic Riccati equation backward in time. The numerical simulation results are finally provided to validate the theoretical control design.

scholarly journals A new active asymmetry monitoring and control technique applied to critical aircraft flap control system failures

2019 ◽  
Vol 304 ◽  
pp. 04011
Author(s):  
Dario Belmonte ◽  
Matteo Davide Lorenzo Dalla Vedova ◽  
Gaetano Quattrocchi
Keyword(s):  
Control System ◽  
Flight Control ◽  
Angular Position ◽  
Control Technique ◽  
Monitoring And Control ◽  
Active Monitoring ◽  
Actuation System ◽  
Left And Right ◽  
And Control ◽  
Current Monitoring

Asymmetry limitation requirements between left and right wing flap surfaces play an important role in the design of the implementation of the secondary flight control system of modern airplanes. In fact, especially in the case of sudden breaking of one of the torsion bars of the flap transmission line, the huge asymmetries that can rapidly develop could compromise the lateral-directional controllability of the whole aircraft (up to cause catastrophic occurrences). Therefore, in order to guarantee the aircraft safety (especially during take-off and landing flight phase in which the effects of asymmetries could generate uncontrollable aircraft attitudes), it is mandatory to timely detect and neutralize these asymmetries. The current monitoring techniques generally evaluate the differential angular position between left and right surfaces and, in most the events, limit the Flaps Control System (FCS) asymmetries, but in severe fault conditions (e.g. under very high aerodynamic loads), unacceptable asymmetries could be generated, compromising the controllability of the aircraft. To this purpose, in this paper the authors propose a new active monitoring and control technique capable of detecting the increasing angular error between the different flap surfaces and that, after stopping the whole actuation system, acts on the portion of the actuation line still connected to the PDU to minimize the FCS asymmetries.

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