MICROFABRICATION OF TWEEZERS WITH LARGE GRIPPING FORCES AND A LARGE RANGE OF MOTION

This paper presents a novel passive redundant spherical joint with a very large range of motion. A kinematic model is first developed in order to provide a framework for the analysis. The principle of the redundant joint is then introduced. The proposed joint does not require any active component since the redundancy is passively handled using springs. A static model of the joint is developed in order to clearly demonstrate how all singularities or jamming configurations can be avoided. Two possible arrangements are presented, one using linear springs and one using a torsional spring. Finally, experimental prototypes are demonstrated that can attain a range of tilt angle of ±150 deg.

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A 3-DOF Translational Compliant Parallel Manipulator Based on Flexure Motion

Volume 7: 33rd Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2009-86075 ◽

2009 ◽

Cited By ~ 3

Author(s):

Guangbo Hao ◽

Xianwen Kong

Keyword(s):

Range Of Motion ◽

Parallel Manipulator ◽

Large Range ◽

Parallel Manipulators ◽

Mathematic Modeling ◽

Ultra Precision ◽

Cross Axis ◽

Force Displacement

This paper presents a novel class of 3-DOF translational compliant parallel manipulators (CPMs) based on flexure motion. The analytic mathematic modeling of CPMs is first developed. The analysis of CPMs is then implemented. It is shown that the proposed CPMs have many characteristics such as large range of motion, negligible cross-axis coupling, actuator complete isolation, and no loss motion and no rotational yaw. The inverse relationships of force-displacement of the 3-DOF CPM are further derived to calculate the input forces required for generating a specified path. In addition, the 3-DOF CPM can also be turned into a 2-DOF CPM. This work lays the foundation for the development of new spatial CPMs based on flexure motions for applications such as ultra precision manipulation.

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Narrative review of injuries in powerlifting with special reference to their association to the squat, bench press and deadlift

BMJ Open Sport & Exercise Medicine ◽

10.1136/bmjsem-2018-000382 ◽

2018 ◽

Vol 4 (1) ◽

pp. e000382 ◽

Cited By ~ 11

Author(s):

Victor Bengtsson ◽

Lars Berglund ◽

Ulrika Aasa

Keyword(s):

Special Reference ◽

Range Of Motion ◽

Bench Press ◽

Large Range ◽

Elite Athletes ◽

Narrative Review ◽

Previous Article ◽

Physical Demands ◽

Lifting Technique ◽

Heavy Loads

Pain and injuries are considered a common problem among elite athletes and recreational lifters performing the squat, bench press and deadlift. Since all three lifts engage multiple joints and expose the lifters’ bodies to high physical demands often several times a week, it has been suggested that their injuries might be related to the excessively heavy loads, the large range of motion during the exercises, insufficient resting times between training sessions and/or faulty lifting technique. However, no previous article has summarised what is known about specific injuries and the injury aetiology associated with the three lifts. Thus, the aim of this narrative review was to summarise what is known about the relationships between the powerlifting exercises and the specific injuries or movement impairments that are common among lifters and recreationally active individuals.

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Processing and Analysis of Long-Range Scans with an Atomic Force Microscope (AFM) in Combination with Nanopositioning and Nanomeasuring Technology for Defect Detection and Quality Control

Sensors ◽

10.3390/s21175862 ◽

2021 ◽

Vol 21 (17) ◽

pp. 5862

Author(s):

Ingo Ortlepp ◽

Jaqueline Stauffenberg ◽

Eberhard Manske

Keyword(s):

Quality Control ◽

High Resolution ◽

Atomic Force Microscope ◽

Range Of Motion ◽

Defect Detection ◽

Large Range ◽

The Other ◽

Atomic Force ◽

Measuring Machine ◽

The One

This paper deals with a planar nanopositioning and -measuring machine, the so-called nanofabrication machine (NFM-100), in combination with a mounted atomic force microscope (AFM). This planar machine has a circular moving range of 100 mm. Due to the possibility of detecting structures in the nanometre range with an atomic force microscope and the large range of motion of the NFM-100, structures can be analysed with high resolution and precision over large areas by combining the two systems, which was not possible before. On the basis of a grating sample, line scans over lengths in the millimetre range are demonstrated on the one hand; on the other hand, the accuracy as well as various evaluation methods are discussed and analysed.

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Differentials in Turnout Among Professional Classical Ballet Dancers

Medical Problems of Performing Artists ◽

10.21091/mppa.2016.3029 ◽

2016 ◽

Vol 31 (3) ◽

pp. 160-165 ◽

Cited By ~ 5

Author(s):

Isobel Washington ◽

Susan Mayes ◽

Charlotte Ganderton ◽

Tania Pizzari

Keyword(s):

Range Of Motion ◽

Lower Limb ◽

Large Range ◽

External Rotation ◽

Ballet Dancers ◽

Bony Landmarks ◽

Professional Dancers ◽

Classical Ballet ◽

Hip Rotation ◽

And Training

BACKGROUND: Screening and training of professional dancers is commonly based around beliefs that a large range of turnout is more advantageous in the ballet industry. This belief leads dancers who have limited hip external rotation to compensate by forcing turnout at the knee and ankle, which has been linked to injury. OBJECTIVE: To examine if there is a difference in degree of turnout between three levels of dancers (corps, soloist, principal) in a professional classical ballet company. An additional aim was to establish average values for the range of turnout and hip rotation present in the dancers. METHODS: Forty-five professional dancers from The Australian Ballet (25 female, 20 male) participated in the study. Active and passive hip external rotation (hip ER) was measured in supine using inclinometers, and functional turnout in ballet first position (lower limb external rotation, LLER) was measured using foot traces utilising bony landmarks. Below-hip external rotation (BHER) was also calculated. RESULTS: No relationship was found among level of dancer and passive hip ER, active hip ER, LLER, and BHER. Professional dancers had on average 50.2° of passive hip ER range, 35.2° of active hip ER, and 133.6° of functional turnout position. In addition, no correlation was found between LLER and hip ER, but significant correlations were found between LLER and BHER. CONCLUSIONS: Hip rotation range of motion is similar across all levels of professional dancers. Average values for passive and active hip ER and functional turnout were established.

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T-Flex: A fully flexure-based large range of motion precision hexapod

Precision Engineering ◽

10.1016/j.precisioneng.2021.08.015 ◽

2021 ◽

Author(s):

M. Naves ◽

M. Nijenhuis ◽

B. Seinhorst ◽

W.B.J. Hakvoort ◽

D.M. Brouwer

Keyword(s):

Range Of Motion ◽

Large Range

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Design of a Human-Like Range of Motion Hip Joint for Humanoid Robots

Volume 5B: 38th Mechanisms and Robotics Conference ◽

10.1115/detc2014-35214 ◽

2014 ◽

Cited By ~ 8

Author(s):

Bryce Lee ◽

Coleman Knabe ◽

Viktor Orekhov ◽

Dennis Hong

Keyword(s):

Range Of Motion ◽

Hip Joint ◽

Disaster Response ◽

Degrees Of Freedom ◽

Humanoid Robot ◽

Large Range ◽

Humanoid Robots ◽

Linkage Mechanism ◽

Joint Torques ◽

Similar Range

For a humanoid robot to have the versatility of humans, it needs to have similar motion capabilities. This paper presents the design of the hip joint of the Tactical Hazardous Operations Robot (THOR), which was created to perform disaster response duties in human-structured environments. The lower body of THOR was designed to have a similar range of motion to the average human. To accommodate the large range of motion requirements of the hip, it was divided into a parallel-actuated universal joint and a linkage-driven pin joint. The yaw and roll degrees of freedom are driven cooperatively by a pair of parallel series elastic linear actuators to provide high joint torques and low leg inertia. In yaw, the left hip can produce a peak of 115.02 [Nm] of torque with a range of motion of −20° to 45°. In roll, it can produce a peak of 174.72 [Nm] of torque with a range of motion of −30° to 45°. The pitch degree of freedom uses a Hoeken’s linkage mechanism to produce 100 [Nm] of torque with a range of motion of −120° to 30°.

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Design, control, and testing of a thumb exoskeleton with series elastic actuation

The International Journal of Robotics Research ◽

10.1177/0278364917694428 ◽

2017 ◽

Vol 36 (3) ◽

pp. 355-375 ◽

Cited By ~ 19

Author(s):

Priyanshu Agarwal ◽

Youngmok Yun ◽

Jonas Fox ◽

Kaci Madden ◽

Ashish D Deshpande

Keyword(s):

Range Of Motion ◽

Degrees Of Freedom ◽

Large Range ◽

Kinematic Model ◽

Torque Control ◽

Thumb Motion ◽

Performance Results ◽

High Degree ◽

Kinematic Mechanism ◽

Series Elastic

We present an exoskeleton capable of assisting the human thumb through a large range of motion. Our novel thumb exoskeleton has the following unique features: (i) an underlying kinematic mechanism that is optimized to achieve a large range of motion, (ii) a design that actuates four degrees of freedom of the thumb, and (iii) a series elastic actuation based on a Bowden cable, allowing for bidirectional torque control of each thumb joint individually. We present a kinematic model of the coupled thumb exoskeleton system and use it to maximize the range of motion of the thumb. Finally, we carry out tests with the designed device on four subjects to evaluate its workspace and kinematic transparency using a motion capture system and torque control performance. Results show that the device allows for a large workspace with the thumb, is kinematically transparent to natural thumb motion to a high degree, and is capable of accurate torque control.

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