Design of a Motor-Driven Mechanism to Conduct Experiments to Determine the Passive Joint Properties of the Human Index Finger

Author(s):  
Pei-Hsin Kuo ◽  
Jerod Hayes ◽  
Ashish D. Deshpande

Our long term goal is to develop a new generation of robotic-prosthetic hands that will incorporate key anatomical features of the human hand, especially, the passive dynamics defined by the joint stifftness and damping properties. This paper presents a design of a mechanism that can measure the passive moment of the human hand joint. We designed a motor-driven system, integrating a noninvasive and infrared motion capture system, that can control and record the angle, angular velocity and passive forces of the metacarpophalangeal (MCP) joint in the index finger. A total of 19 subjects participated in the experiments. We conducted two experiments to estimate the total passive moments of the MCP joint from the human subjects. The results showed that the novel design of the mechanism collected the precise passive moments and kinematic data, thus allowing us to develop a comprehensive understanding of the passive properties of the human hand joints.

2018 ◽  
Vol 76 (5) ◽  
pp. 515-537 ◽  
Author(s):  
Neeraj Bhandari ◽  
Dennis P. Scanlon ◽  
Yunfeng Shi ◽  
Rachel A. Smith

Despite growing investment in producing and releasing comparative provider quality information (CQI), consumer use of CQI has remained poor. We offer a framework to interpret and synthesize the existing literature’s diverse approaches to explaining the CQI’s low appeal for consumers. Our framework cautions CQI stakeholders against forming unrealistic expectations of pervasive consumer use and suggests that they focus their efforts more narrowly on consumers who may find CQI more salient for choosing providers. We review the consumer impact of stakeholder efforts to apply the burgeoning knowledge of consumers’ cognitive limitations to the design and dissemination of the new generation of report cards; we conclude that while it is too limited to draw firm conclusions, early evidence suggests consumers are responding to the novel design and dissemination strategies. We find that consumers continue to have difficulty accessing reliable report cards, while the media remains underused in the dissemination of report cards.


2015 ◽  
Vol 7 (3) ◽  
Author(s):  
Pei-Hsin Kuo ◽  
Jerod Hayes ◽  
Ashish D. Deshpande

Passive properties of the human hands, defined by the joint stiffness and damping, play an important role in hand biomechanics and neuromuscular control. Introduction of mechanical element that generates humanlike passive properties in a robotic form may lead to improved grasping and manipulation abilities of the next generation of robotic hands. This paper presents a novel mechanism, which is designed to conduct experiments with the human subjects in order to develop mathematical models of the passive properties at the metacarpophalangeal (MCP) joint. We designed a motor-driven system that integrates with a noninvasive and infrared motion capture system, and can control and record the MCP joint angle, angular velocity, and passive forces of the MCP joint in the index finger. A total of 19 subjects participated in the experiments. The modular and adjustable design was suitable for variant sizes of the human hands. Sample results of the viscoelastic moment, hysteresis loop, and complex module are presented in the paper. We also carried out an error analysis and a statistical test to validate the reliability and repeatability of the mechanism. The results show that the mechanism can precisely collect kinematic and kinetic data during static and dynamic tests, thus allowing us to further understand the insights of passive properties of the human hand joints. The viscoelastic behavior of the MCP joint showed a nonlinear dependency on the frequency. It implies that the elastic and viscous component of the hand joint coordinate to adapt to the external loading based on the applied frequency. The findings derived from the experiments with the mechanism can provide important guidelines for design of humanlike compliance of the robotic hands.


2019 ◽  
Vol 13 (3) ◽  
Author(s):  
Betul Mammadov ◽  
Gulsen Vural ◽  
Ersin Aytac ◽  
Emil Mammadov

Parents frequently report complaints regarding the excessive size of the clamp that create concerns of hooking to the clothes and inducing premature separation of the dried cord. We aimed to design three-dimensional (3D) print and test a novel umbilical clamp which would be smaller, more ergonomic, and would look more appealing to the parents. After the design and 3D printing process, the clamps were tested for fluid leak on fresh umbilical cord specimens. The umbilical vein was cannulated with a 4F feeding tube which was attached to the saline infusion bag inserted in a pressure infusion cuff. The compressed cord width was measured, and the cuff was inflated to 100 mmHg and 200 mmHg. Umbilical cord specimens of 152 patients were included in the main study. The mean umbilical cord diameter (UCD) was 11.1 ± 3.5 mm (range: 4.5–23.3 mm). The compressed cord width mean value after clamping with the novel design clamp was 17.3 ± 2.3 mm compared to the 23.5 ± 3.5 mm with the conventional clamp and this difference was statistically significant (p < 0.001). All of the novel clamps safely and efficiently clamped the umbilical cords without any fluid leak. The novel design umbilical cord clamp is a safe and efficient tool being able to clamp a wide range of umbilical cords. However, a prospective randomized trial on human subjects, safety-efficacy tests by independent healthcare providers, and patient satisfaction surveys are mandatory for the further approval of our claims.


2021 ◽  
Vol 7 ◽  
Author(s):  
John-John Cabibihan ◽  
Farah Alkhatib ◽  
Mohammed Mudassir ◽  
Laurent A. Lambert ◽  
Osama S. Al-Kwifi ◽  
...  

The field of rehabilitation and assistive devices is being disrupted by innovations in desktop 3D printers and open-source designs. For upper limb prosthetics, those technologies have demonstrated a strong potential to aid those with missing hands. However, there are basic interfacing issues that need to be addressed for long term usage. The functionality, durability, and the price need to be considered especially for those in difficult living conditions. We evaluated the most popular designs of body-powered, 3D printed prosthetic hands. We selected a representative sample and evaluated its suitability for its grasping postures, durability, and cost. The prosthetic hand can perform three grasping postures out of the 33 grasps that a human hand can do. This corresponds to grasping objects similar to a coin, a golf ball, and a credit card. Results showed that the material used in the hand and the cables can withstand a 22 N normal grasping force, which is acceptable based on standards for accessibility design. The cost model showed that a 3D printed hand could be produced for as low as $19. For the benefit of children with congenital missing limbs and for the war-wounded, the results can serve as a baseline study to advance the development of prosthetic hands that are functional yet low-cost.


2007 ◽  
Vol 361-363 ◽  
pp. 411-414 ◽  
Author(s):  
Gaelle Jouan ◽  
Eric Goyenvalle ◽  
Eric Aguado ◽  
Ronan Cognet ◽  
Françoise Moreau ◽  
...  

Resorbable osteosynthesis based on PLLA and derivatives will be associated to bone substitute for bone reconstruction. We have performed rand evaluated a composite combining PL DLLA and Biphasic calcium phosphate able to have a), a better controlled hydrolysis in the purpose to preserve on time the mechanical property, and b), for long term efficiency, bone ingrowth at the expense of the osteosynthesis and the associated bone substitute. A new calcium phosphate cement MCPC® was tested with such composite. The novel macroporous calcium phosphate cement MCPC sets to poorly crystalline apatite after mixing the powder component and an aqueous solution. Interconnective macroporosity was induced on time by resorption of one part of the MCPC®. The multiphasic calcium phosphate components in the cement, are resorbed at different rates allowing the replacement by newly formed bone. This study reports the biocompatibility and the interactions of a composite using PL DLLA (Poly [L-Lactide-co-D,L-Lactide] acid) charged with biphasic calcium phosphate granules and a self setting calcium phosphate cement of new generation.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Zachary Ray ◽  
Erik D. Engeberg

Autonomously preventing grasped objects from slipping out of prosthetic hands is an important feature for limb-absent people since they cannot directly feel the grip force applied to grasped objects. Oftentimes, a satisfactory grip force in one situation will be inadequate in different situations, such as when the object is rotated or transported. Over time, people develop a grip reflex to prevent slip of grasped objects when they are rotated with respect to gravity by their natural hands. However, this reflexive trait is absent in commercially available prosthetic hands. This paper explores a human-inspired grasp reflex controller for prosthetic hands to prevent slip of objects when they are rotated. This novel human-inspired grasped object slip prevention controller is evaluated with 6 different objects in benchtop tests and by 12 able-bodied subjects during human experiments replicating realistic tasks of daily life. An analysis of variance showed highly significant improvement in the number of successfully completed cycles for both the benchtop and human tests when the slip prevention reflex was active. An object sorting task, which was designed to serve as a cognitive distraction for the human subjects while controlling the prosthetic hand, had a significant impact on many of the performance metrics. However, assistance from the novel slip prevention reflex mitigated the effects of the distraction, offering an effective method for reducing both object slip and the required cognitive load from the prosthetic hand user.


2013 ◽  
Vol 10 (02) ◽  
pp. 1350001 ◽  
Author(s):  
MICHAEL A. SALIBA ◽  
ALISTAIRE CHETCUTI ◽  
MATTHEW J. FARRUGIA

In this work, we take a new approach to the determination of the quantified contribution of various attributes of the human hand to its dexterity, with the aim of transposing this knowledge into supportive guidelines for the design of anthropomorphic robotic and prosthetic hands. We have carried out a number of standard dexterity tests on normal human subjects with various physical constraints applied to selected attributes of their hands, and have analyzed the results of the tests to extract knowledge on the quantified contribution of each attribute to overall manual dexterity. This knowledge is particularly significant in cases where it is important to optimize the trade-off between dexterity and complexity in the design of artificial hands. The data collection was made over 35 h of direct experimentation involving 40 volunteers during two separate runs, and the results represent empirically-derived upper limits on the achievable performance of humanoid robot hands having the specified deficiencies. We discuss the implications of our results in the context of a minimal anthropomorphic dexterous hand, which would incorporate the lowest possible number of degrees of freedom and other attributes while still retaining an acceptable level of dexterity. We end the paper with a suggestion on how the general approach presented herein could be extended to provide a platform for the quantification of the dexterity of anthropomorphic artificial hands.


2018 ◽  
Vol 6 (2) ◽  
pp. 122
Author(s):  
Widya Prana Rini

Abstrak             Penelitian ini membahas karya sastra yang membawa isu alam dan lingkungan tereksploitasi melalui sistem pertanian sebagai sarana merawat bumi. Perusakan lingkungan pertanian Desa Kailasa merupakan pokok permasalahan tokoh Yahya dalam penyelamatan alam dan lingkungan. Adanya gerak komunal petani yang bersifat antroposentris membuka kontestasi untuk mengakses sumber daya alam. Alam dimanfaatkan untuk mendapatkan keuntungan besar, baik pihak petani maupun pihak lain yang berkepentingan, akan tetapi tidak ada keseimbangan area pertanian jangka panjang. Melalui sudut pandang ekokritik mencermati narasi penyelamatan ekosistem dalam kontestasi kepentingan ekologis. Penelitian ini menggunakan teori ekokritik yang bertolak pada pandangan Cheryll Goltfelty. Metode yang digunakan deskriptif kualitatif. Antroposentris membuat alam dan lingkungan Kailasa terdegradasi terlihat dari manusia yang mengekploitasi alam. Teridentifikasi masyarakat Kailasa mengalami pergeseran kesadaran eko ke kesadaran ego, perubahan tersebut dilatarbelakangi oleh hidup yang berorientasi pada materi untuk kepentingan ekonomi. Ada kecenderungan yang mengarah ke kesadaran eko, terlihat pada generasi baru setelah lima belas tahun terjadi kontestasi, akan tetapi hanya berubah pada tanaman polikultur (tanaman carika). Narasi yang diuraikan terlihat mewakili pemikiran ekosentrisme yang melindungi dari kejahatan antroposentris, akan tetapi terdapat paradoks dalam memperjuangkan ekosistem yang direpresentasikan. Teridentifikasi dari masyarakat Kailasa yang tetap menggunakan cara pandang antroposentris walaupun alam dan lingkungan telah mengalami degradasi. Kata Kunci : ekologi,  ekosistem, antroposentris, ekosentris, ekstensifikas, intensifikasi, kontestasi.     Abstract This research discusses a literature that brings the issue about nature and environmental issues exploited by a farming system as means of caring for the earth. Environment represented in the novel entitled Kailasa by Jusuf AN as a form of ecology criticism and how the narrative of ecosystem rescuse in the contestation of ecological. The purpose of this research is to identify environmental damage and what attitude that should be taken as an act of saving nature and the environment in contestation of acosystem diversity. The destruction of the agricultural environment of Kailasa Village is the main issue of Yahya's character in saving nature and the environment. The anthropocentric nature of farmers' communal movements opens contestation to access natural resources. Nature is used to gain big profits, both farmers and other interested parties, but there is no balance of long-term agricultural areas. Through an ecocritical point of view, look at the narrative of saving ecosystems in the contestation of ecological interests. This research uses an ecocritism in literature that depart from the view of Cheryll Goltfelty. The method used is descriptive kualitative to dissect the problem. Anthropocentric make Kailasa nature and environment degraded which can be seen from humans who exploit nature. It is identified that there is a shift of eco to ego consiousness in Kailasa communitty while the change is motivated by material-oriented life for the sake of the economy. After nature is degraded, there is a tendency to back eco consiousness. Seen in the new generation after fifteen years of contestation, but changed on polyculture plants (carica). Narrative described appears to represent the ecocentric thinking that protects evil anthropocentris, but there is a paradox in the struggle for represented ecosystems. It is identefied from Kailasa community that they keep the antrhoposentric perspective though nature and the environment has been degraded.Keywords: ecocritic, ecosistem, antrophocentric, ecocentric, extensification, intencification, contestation.


VASA ◽  
2013 ◽  
Vol 42 (5) ◽  
pp. 340-349 ◽  
Author(s):  
Ivan Kralj ◽  
Irene Boos ◽  
Uwe Müller-Bühl

Background: Advances in stent technology have widened the field of indications for stent treatment of femoro-popliteal artery lesions, however the use of stents in bending arterial segments is restricted because some first- and second-generation nitinol stent designs did not respond well to the mechanical forces of femoro-popliteal segments in motion which pose a substantial risk of stent fracture inducing in-stent-stenosis. New generation nitinol stents are supposed to overcome these limitations but long-term results are rare. Patients and methods: In forty-five patients (mean age 68 y, range 50 - 85) with peripheral arterial disease (TASC II A-C, Rutherford category 2 - 5) forty-six lesions of the superficial femoral artery (37) or popliteal artery (9) were treated [25 high-grade stenoses, mean length 53 mm (range 30 - 145 mm); 21 chronic total occlusions, mean length 74 mm (range 30 - 180 mm)]. 74 % of lesions were located in the mobile bending arterial segments in the distal femoral or the popliteal segment. Clinical reevaluation performed at discharge, at 6, 12, 24, and 36 months included at least the measurement of ankle-brachial index (ABI) and duplex sonography. Results: Procedural success rate was 100 %. At 6, 12, 24, and 36 months, cumulative primary patency rate was 93.5 %, 84.8 %, 80.5 %, and 74.3 % (SE<10); freedom from target lesion revascularization rate was 95.7 %, 89.2 %, 84.9 %, and 79.3 % (SE<10); Rutherford category and ABI improved in all patients and clinical success was maintained in more than 85 % of patients. Conclusions: Sustained technical and clinical success and good clinical long-term results were achieved with Misago™ nitinol stent implantation in femoro-popliteal lesions with moderate risk for in-stent-stenosis, and in the distal femoral and popliteal mobile segment.


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