Novel Robotic System for Joint Mechanical Tests Using Velocity-Impedance Control

2011 ◽  
Author(s):  
Hiromichi Fujie ◽  
Hitoshi Yagi
Keyword(s):  
Impedance Control ◽  
Mechanical Tests ◽  
Robotic System ◽  
High Rate ◽  
Robotic Technology ◽  
High Speeds ◽  
Custom Made ◽  
Force Moment ◽  
Displacement Force ◽  
Large Work

The first study as regard with the application of robotic technology to the field of joint biomechaics was reported more than 20 years ago1). Since then, a variety of studies have employed commercially available articulated manipulators for the joint biomechanical studies1–4). However, such articulated manipulators are generally poor at stiffness and precision although they were basically designed to achieve high speeds of motion while performing tasks in a large work space. To solve the problem, we have previously developed a robotic system consisting of a custom-made 6-degree of freedom (6-DOF) manipulator and a universal force-moment sensor (UFS)5). Referring to the robotic system, the present study was aimed to develop a novel robotic system of rigid body/structure that allows a high-rate displacement/force control of the knee using a velocity-impedance control.

Static and Dynamic Properties of a 6-DOF Robotic System for Knee Joint Biomechanics Study

2013 ◽  
Author(s):  
Hiromichi Fujie ◽  
Kei Kimura ◽  
Satoshi Yamakawa
Keyword(s):  
Knee Joint ◽  
Dynamic Properties ◽  
Robotic System ◽  
Robotic Technology ◽  
Work Space ◽  
High Speeds ◽  
Custom Made ◽  
Force Moment ◽  
Joint Biomechanics ◽  
Large Work

The application of robotic technology to the field of joint biomechaics has started more than 20 years ago 1). Since then, a variety of studies have employed commercially available articulated manipulators for the joint biomechanical studies 1–5). However, such articulated manipulators are generally poor at stiffness and precision although they were basically designed to achieve high speeds of motion while performing tasks in a large work space. To solve the problem, we have previously developed a robotic system consisting of a custom-made 6-degree of freedom (6-DOF) manipulator and a universal force-moment sensor (UFS) 6). The present study was aimed to evaluate the static and dynamic properties of the system.

Development of an autonomous robotic system for beard shaving assistance of disabled people based on an adaptive force tracking impedance control

2021 ◽  
pp. 095440622098482
Author(s):  
Oladayo S Ajani ◽  
Samy FM Assal
Keyword(s):  
Impedance Control ◽  
Environmental Parameters ◽  
Robotic System ◽  
Robotic Systems ◽  
Full Potential ◽  
Robotic Assistance ◽  
Head Pose ◽  
Detection And Tracking ◽  
Control Scheme ◽  
Force Tracking

Recently, people with upper arm disabilities due to neurological disorders, stroke or old age are receiving robotic assistance to perform several activities such as shaving, eating, brushing and drinking. Although the full potential of robotic assistance lies in the use of fully autonomous robotic systems, these systems are limited in design due to the complexities and the associated risks. Hence, rather than the shared controlled or active robotic systems used for such tasks around the head, an adaptive compliance control scheme-based autonomous robotic system for beard shaving assistance is proposed. The system includes an autonomous online face detection and tracking as well as selected geometrical features-based beard region estimation using the Kinect RGB-D camera. Online trajectory planning for achieving the shaving task is enabled; with the capability of online re-planning trajectories in case of unintended head pose movement and occlusion. Based on the dynamics of the UR-10 6-DOF manipulator using ADAMS and MATLAB, an adaptive force tracking impedance controller whose parameters are tuned using Genetic Algorithm (GA) with force/torque constraints is developed. This controller can regulate the contact force under head pose changing and varying shaving region stiffness by adjusting the target stiffness of the controller. Simulation results demonstrate the system capability to achieve beard shaving autonomously with varying environmental parameters that can be extended for achieving other tasks around the head such as feeding, drinking and brushing.

Aortic Remodeling After Custom-Made Candy-Plug for Distal False Lumen Occlusion in Aortic Dissection

2021 ◽  
pp. 152660282199672
Author(s):  
Ahmed Eleshra ◽  
Fiona Rohlffs ◽  
Konstantinos Spanos ◽  
Giuseppe Panuccio ◽  
Franziska Heidemann ◽  
...  
Keyword(s):  
Aortic Dissection ◽  
Clinical Success ◽  
False Lumen ◽  
High Rate ◽  
Single Center ◽  
Original Design ◽  
Mortality And Morbidity ◽  
Custom Made ◽  
Aortic Remodeling

Purpose: To report a single-center experience with the use of a custom-made Candy-Plug (CP) for distal false-lumen (FL) occlusion in subacute and chronic aortic dissection (AD). Materials and Methods: A retrospective single-center analysis was conducted on consecutive patients with subacute and chronic AD who were treated with a custom-made CP for distal FL occlusion using 3 design generations (CP I to CP III) from October 2013 to September 2019. Results: A custom-made CP was used in 57 patients. Of these, 34 patients (29 males, mean age 62±10 years) were treated with a CP I vs 23 patients (16 males, mean age 59±17 years) with CP II/III. Technical success was achieved in 57 (100%) patients. Clinical success was achieved in 54 (95%) patients; 33 (97%) in CP I group vs 21 (91%) patients in CP II/III group, p=0.116. The mean hospital stay was 10±8 days (9±5 days in CP I group vs 13±9 days in CP II/III, p=0.102). The 30-day computed tomography angiography (CTA) confirmed successful CP placement at the intended level in all patients within both groups. Early complete FL occlusion was achieved in 50 (88%) patients; 30 (88%) patients in CP I group vs 20 (87%) in CP II/III group, p=0.894. Follow up CTA was available in 44 (77%) patients. Of these; 30/34 (88%) patients in CP I group with mean follow-up 29±17 months) vs. 14/23 (61%) patients with mean follow-up 14±5 months in CP II/III group. Thoracic aortic remodeling was achieved in 34/44 (77%) patients; 25/30 (83%) patients in CP I group vs 9/14 (64%) patients in CP II/III group, p=0.197. The aneurysm size remained stable in 9/44 (20%) patients; 5/30 (17%) patients in CP I group vs 4/14 (29%) patients in CP II/III group, p=0.741. The thoracic aneurysm increased size was seen in 1/44 (2%) patient. This patient was in CPII/III group. Conclusion: CP technique using custom-made devices is technically feasible with a low mortality and morbidity, and a high rate of aortic remodeling. Both, the original design (CP I) and newer designs with a self-closing central sleeve (CP II and CP III) showed similar excellent outcomes.

High-rate deposition of Sb-doped SnO2 films by reactive sputtering using the impedance control method

2011 ◽  
Vol 520 (4) ◽  
pp. 1178-1181 ◽  
Author(s):  
Yu Muto ◽  
Nobuto Oka ◽  
Naoki Tsukamoto ◽  
Yoshinori Iwabuchi ◽  
Hidefumi Kotsubo ◽  
...  
Keyword(s):  
Control Method ◽  
Impedance Control ◽  
Reactive Sputtering ◽  
High Rate

High Rate of Early Revision After Custom-Made Unicondylar Knee Arthroplasty

2018 ◽  
Vol 33 (7) ◽  
pp. S100-S104
Author(s):  
Carl T. Talmo ◽  
Marie C. Anderson ◽  
Eliot S. Jia ◽  
Claire E. Robbins ◽  
Jason D. Rand ◽  
...  
Keyword(s):  
Knee Arthroplasty ◽  
Unicondylar Knee Arthroplasty ◽  
High Rate ◽  
Early Revision ◽  
Custom Made

Robust Impedance Control of Manipulators Carrying a Heavy Payload

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Farhad Aghili
Keyword(s):  
Force Measurement ◽  
Impedance Control ◽  
Stability And Convergence ◽  
Robot Dynamics ◽  
Control Input ◽  
Heavy Load ◽  
Impedance Model ◽  
Force Moment ◽  
Loop Feedback ◽  
The Stability

A heavy payload attached to the wrist force/moment (F/M) sensor of a manipulator can cause the conventional impedance controller to fail in establishing the desired impedance due to the noncontact components of the force measurement, i.e., the inertial and gravitational forces of the payload. This paper proposes an impedance control scheme for such a manipulator to accurately shape its force-response without needing any acceleration measurement. Therefore, no wrist accelerometer or a dynamic estimator for compensating the inertial load forces is required. The impedance controller is further developed using an inner/outer loop feedback approach that not only overcomes the robot dynamics uncertainty, but also allows the specification of the target impedance model in a general form, e.g., a nonlinear model. The stability and convergence of the impedance controller are analytically investigated, and the results show that the control input remains bounded provided that the desired inertia is selected to be different from the payload inertia. Experimental results demonstrate that the proposed impedance controller is able to accurately shape the impedance of a manipulator carrying a relatively heavy load according to the desired impedance model.

scholarly journals Investigation on Mechanical and Durability Properties of Rapid Strength Gaining Concrete

2018 ◽  
Vol 7 (2.12) ◽  
pp. 406
Author(s):  
L Krishnaraj ◽  
P T. Ravichandran ◽  
Shaik AarifIlahi ◽  
V Ramanathan
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Cement Paste ◽  
Mechanical Tests ◽  
High Rate ◽  
Concrete Technology ◽  
Strength Concrete ◽  
Durability Properties ◽  
Content Ratio ◽  
Strength Tests

The strength of cement paste and aggregate components helps to decide the strength of the concrete, their properties of deformation, and the binding properties among the aggregate surface and cement paste. It is conceivable with many of the aggregates to form high strength concrete by increasing the cement paste strength, which can be controlled by choosing of water-content ratio and type of admixture dosage. The current scenario in the concrete technology and the accessibility of many kind of mineral and chemical admixtures, and special super plasticizer to gain the targeted compressive strength of a concrete. In this study MYK Remicrete PC30 and BASF Master Glennium ACE 30 were utilized as the admixtures as Add 1 and Add 2 which acts as high rate water reducing agents. These developments have led to increase uses of Rapid strength concrete. To compare the mechanical and durability properties of concrete using Fly ash and Admixtures the following tests were conducted on concrete tests specimens. Mechanical tests are to be conducted such as compressive strength tests, and tensile strength tests, durability tests like water absorption test, acid test by HCL, H2SO4 and HNO3. The result indicates that rate of development of compressive strength and tensile strength are higher for the concrete design mix which has HRWR admixture of 1% and FA of 20%.  

Impedance Control of Manipulators With Heavy Payload for Spacecraft Rendezvous and Docking Simulators

2009 ◽  
Author(s):  
Farhad Aghili
Keyword(s):  
Sensitivity Analysis ◽  
Rigid Body ◽  
Impedance Control ◽  
Sensor Noise ◽  
Combined System ◽  
Laboratory Environment ◽  
Force Moment ◽  
Applied Forces ◽  
The Stability ◽  
Rendezvous And Docking

This paper presents a method to control a manipulator system grasping a rigid-body payload so that the motion of the combined system in consequence of external applied forces to be the same as another free-floating rigid-body (with different inertial properties). This allows zero-g emulation of a scaled spacecraft prototype under the test in a 1-g laboratory environment. The controller consisting of motion feedback and force/moment feedback adjusts the motion of the test spacecraft so as to match that of the flight spacecraft. The stability of the overall system is analytically investigated, and the results show that the system remains stable provided that the inertial properties of two spacecraft are different and that an upperbound on the norm of the inertia ratio of the payload to manipulator is respected. Important practical issues such as calibration and sensitivity analysis to sensor noise and quantization are also presented. Finally, experimental results are presented.

scholarly journals Mid-term Outcomes of Using Custom-Made Implants for Revision Hip Arthroplasty

2019 ◽  
Vol 25 (3) ◽  
pp. 37-46 ◽  
Author(s):  
A. N. Kovalenko ◽  
A. A. Dzhavadov ◽  
I. I. Shubnyakov ◽  
S. S. Bilyk ◽  
A. O. Denisov ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Hip Joint ◽  
High Rate ◽  
Long Term Results ◽  
Porous Coating ◽  
Short Term ◽  
Custom Made ◽  
Acetabular Defects

Introduction. The matter of the replacement of acetabular defects is becoming increasingly relevant today. In their clinic the authors used custom-made implants with trabecular coating for replacement of defects in the acetabulum where and when it was necessary to ensure extended fixation of the component. Purpose — to evaluate short-term clinical and functional outcomes, osteointegration of porous coated custom-made implants, the overall survival of structural components and to identify the causes of failures and complications. Materials and Methods. During the study the authors interviewed and evaluated radiographs of 48 patients operated from October 2015 to June 2018. The patients were interviewed before and after the surgery using the Oxford hip joint scale, quality of life EQ-5D and visual analogue pain scale. Radiographs were evaluated for a period of at least 12 months for the signs of osteointegration. Results. The average OHS scores increased from 14.9 (±7) to 37.6 (±7) (p<0.01). Quality of life according to the EQ-5D index increased from 0.2 (±0.2) to 0.7 (±0.2) (p<0.01). The average value by general health scales: before operations — 49 (±17) and 73 (±18) scores after surgeries (p<0.01). The average VAS pain score decreased from 73 (±10) to 19 (±19) points (p<0.01). Osteointegration was observed in 98 percent of cases. Migration of the implant with fracture of a flange was observed in one case. Conclusions. In the short-term follow up the use of custom-made implants significantly improves hip joint function and the patients’ life quality. Custom-made implants enable primary reliable fixation in case of complex acetabular defects. High rate of osteointegration is observed for custom-made implants with porous coating within at least 12 months. Longer follow-up is needed to evaluate long-term results.

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