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Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： med Amine LARIBI Lotfi ROMDHANE sad ZEGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with Denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method Denevit-Hartenberg parameters Mechanism synthesis

Regional Climate Models in the Simulation of the Drought of the 1970’s and 1980’s Years in Senegal (In West Africa)

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Journal of Water Resource and Protection 2024年第9期16卷 585-604页

作者： Mamadou sarr Adoum Mahamat Moussa Malick Wade el Hadji Deme Bouya Diop Laboratoire des Sciences de lAtmosphre et des Ocans Matriaux-Energies-Dispositifs (LsaO-med) Universit Gaston Berger Saint-Louis Sngal Ecole Nationale Suprieur des TIC (ENASTIC) NDjamena Tchad Laboratoire dEtudes et de Recherches en Statistique et Dveloppement (LERSTAD) Universit Gaston Berger Saint-Louis Sngal

West Africa was hit by an unprecedented drought in the 1970’s and 1980’s years, with dramatic consequences for surface and groundwater resources. In the context of climate change, there are many studies for the prediction of the increase in the occurrence of these droughts. To predict this situation in the Senegalese region, it is necessary to use regional climate models, which carrying out the study. This work deals with the interest to examine the capacity of the RCMs (regional climate models) in order to reproduce the deficit on the 1970’s year rainfall in Senegal. In this work, we used daily precipitation data from five (5) regional climate models to characterize the droughts in Senegal by using the SPI (Standardized Precipitation Index) on different time scales (3, 6, 12 and 24 months). For this purpose, the index was calculated over two distinct periods: 1951-1969 and 1970-1990. The results show that the period 1970-1990 was drier than the period 1951-1969. For the zonal average, the results show that the North of Senegal was more affected by this deficit rainfall than the South part. The analysis of the interannual variability of rainfall for some stations in Senegal shows that the drought did not start at the same time throughout the zone.

关键词： Climate Change Drought SPI (Standardised Precipitation Index) Senegal

On the Optimal Design of Cable Driven Parallel Robot with a Prescribed Workspace for Upper Limb Rehabilitation Tasks

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Journal of Bionic Engineering 2019年第3期16卷 503-513页

作者： Laribi med Amine Carbone Giuseppe Zeghloul said Department of GMSC Pprime Institute CNRS-University of Poitiers - ENSMA - UPR 3346 Poitiers France Department of Mechanical Energy and Management Engineering University of Calabria 87036 Rende Italy CESTER Technical University of Cluj-Napoca Muncii Ave. 103-105 400641 Cluj-Napoca Romania

This paper deals with an optimization approach to design a cable driven parallel robot intended for upper limb rehabilitation tasks. The cable driven parallel robots have characteristics that make them best candidate for rehabilitation exercise purposes such as large workspace, re-configurable architecture, portability and cost effectiveness. Here, both the cable tensions that are needed to move a wristband as well as the workspace need to be carefully optimized for fulfilling the prescribed operation tasks. A specific case of study is addressed in this work by referring to LA RM wire driven exercising device (LAWEX), which is applied to upper limbs exercises. To that end, a motion capture system is used to collect quantitative data on the prescribed workspace of a human upper limb. A specific optimization problem is settled up for considering combining two optimization goals, namely, the smallest robot size reaching a prescribed workspace and the minimum cable tension distributions. A sequence of optimization steps is defined using Genetic Algorithms (GAs) applied to LAWEX robot. The proposed objective function is based on a mathematical formulation of the power of a point with respect to bounding surfaces in combination with a performance index to show the distributions of the minimum cable tensions.

关键词： LAWEX robot design bionic robot cable-driven robots optimization power of the point rehabilitation tasks

Maternal Fetal Prognosis: Pregnancy and Delivery in Women of 40 Years Old and Over in a Second Reference Hospital in Bamako

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Open Journal of Obstetrics and Gynecology 2024年第4期14卷 509-519页

作者： samaké Alou Diarra Lasseny Keita Mamadou Haidara Dramane Haidara Mamadou Diallo Mamadou Konaté Moussa Maiga Mariam Mohamed saydi Ag med elmehdi elansari Kassogue Djibril Seydou Zana Dao samake Hawa Konate Karim Dembele Bertin Coulibaly Moussa Mariko Seydou Collarete Dohino Reference Health Center of Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (BDH) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Timbuktu Hospital Timbuktu Mali Reference Health Center of Commune II of the Bamako District Bamako Mali Reference Health Center in Commune V of the Bamako District Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Late pregnancies are considered a public health problem linked to maternal mortality due to their complications. These risks, which worsen with maternal age, should be better known and taken into account in monitoring these pregnancies. Objective: To evaluate the impact of age on the prevalence of obstetric and neonatal complications among parturients of 40 years old and over. Methodology: This was an 11-year retrospective analytical case control study from January 1, 2007 to December 31, 2017. The study population was female patients of 40 years old or older for cases and female patients younger than 40 years of control case. Results: In total, we collected 640 cases of parturients of 40 years old and over out of a total of 84,234 deliveries during the study period;i.e. a frequency of 0.76%. Spontaneous abortion increased in patients of 40 and over with 8.28%. Hypertension and diabetes were higher of women of 40 and over, 52.65%. Concerning the method of admission: 55% of parturients of 40 and over were referrals. Incidents occurring among women of 40 and over were more pronounced than in control cases. Complications during vaginal delivery, cervical tear, perineal tear, uterine dehiscence and uterine rupture are high in our cases, i.e. 11.88%;3.59%;2.19%;2.66. During our study, depending on the type of delivery, the cesarean rate was much higher among women of 40 and over than among control cases, i.e. 54.22% versus 12.24%. Hemorrhages in the 3rd trimester were the main indications for cesarean section. Hemorrhages in the 3rd trimester were more frequent with women of 40 and over, i.e. 10.47%;5.94% versus 1.74% and 0.42%. As for the different types of malformations in parturients, women under 40 years old fetal malformations were absent in 92.29%, on the other hand they were more frequent in patients with 40 years and over, i.e. a normal frequency of 36.72%. Conclusion: Pregnancy at a late age exposes the elderly patient and the newborn to several ri

关键词： Advanced Maternal Age Childbirth Risk Mali

Maternal and Perinatal Prognosis of Arterial Hypertension and Pregnancy in a Peripheral Health Center in Mali

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Open Journal of Obstetrics and Gynecology 2024年第5期14卷 855-867页

作者： samaké Alou Diarra Lasseny Keita Mamadou Haidara Dramane Haidara Mamadou Diallo Mamadou Konaté Moussa Maiga Mariam MS Ag med elméhdi elansari Kassogue Djibril Dao Seydou Zana samake Hawa Konate Karim Dembele Bertin Coulibaly Moussa Mariko Seydou Colette Dohinnon Reference Health Center in Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (HDB) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Timbuktu Hospital Timbuktu Mali Reference Health Center of Commune II of the Bamako district Bamako Mali Reference Health Center in Commune V of the Bamako district Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Maternal mortality constitutes a public health problem and its rate is an indicator of a country’s development. Among the causes of maternal and perinatal death, high blood pressure associated with pregnancy occupies a significant part. It represents 5% of direct maternal deaths. Objective: to study the maternal and perinatal prognosis of high blood pressure during pregnancy in the Tenenkou reference health center in Mali. Methodology: This was a descriptive, analytical and retrospective cross-sectional study over a period of twelve months from January 1, 2021 to December 31, 2021 and involving 144 cases of high blood pressure associated with pregnancy. Results: We obtained a frequency of 11.75%. The majority of patients 70.9% were aged between 20 - 35 years. The important risk factor found was young age. During our study, 46.5% of patients had performed at least one CPN and only 13.9% performed 04 CPN. Pre-eclampsia was the most common type of high blood pressure during pregnancy, i.e. 61.1%. Eclampsia and retroplacental hematoma were the most common maternal complications, respectively 27.8% and 11.1%. The most common fetal complications were premature births and fetal distress with 20.9% and 17.4% respectively. Conclusion: Hypertension associated with pregnancy still remains a major cause of maternal-fetal morbidity and mortality in our context where diagnosis is often late. The main clinical form was preeclampsia. Eclampsia and retroplacental hematoma were the most frequent maternal complications. Fetal complications were mainly prematurity and fetal distress.

关键词： Pregnancy High Blood Pressure Prognosis

Epidemiological-Clinical Aspects of Uterine Leiomyoma at the Reference Health Center of Commune VI of the Bamako District

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Open Journal of Obstetrics and Gynecology 2024年第5期14卷 674-681页

作者： Alou samaké Lasseny Diarra Mamadou Keita Dramane Haidara Mamadou Haidara Coulibaly Soumana Mamadou Diallo Moussa Konaté Mariam Maiga MS Ag med elméhdi elansari Kassogue Djibril Dao Seydou Zana samake Hawa Konate Karim Dembele Bertin Coulibaly Moussa Mariko Seydou Colette Dohino Reference Health Center of Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (HDB) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Hangadoumbo Moulaye Touré Hospital in Gao Gao Mali Timbuktu Hospital Tomboctou Mali Reference Health Center of Commune II of the Bamako District Bamako Mali Reference Health Center in Commune V of the Bamako District Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Uterine fibroid is a mixed mesenchymal tumor, developing from smooth muscle cells of the myometrium, separated by connective tissue. The majority of fibroids are asymptomatic and do not require any intervention or other exploratory measures. However, in some cases fibroids are symptomatic, their treatment should aim to improve symptoms and quality of life. Objectives: Describe the epidemiological-clinical aspects of uterine fibroids in the gynecology and obstetrics department of the reference health center of commune VI of the Bamako district. Methodology: This was a retrospective descriptive study carried out over a period of one year. It concerns all patients seen in consultation in the gynecology and obstetrics department of the reference health center of commune VI. Results: during the study period, the uterine fibroid frequency was 1.80%. During this same period, fibroids represented 5.59% of gyneco-obstetric pathologies operated on in the department. The 30 - 45 year old age group was the most represented with a frequency of 75.63%. The average age was 36.87 years ± 6.2 years with extremes of 25 and 63 years. Married women were the most represented 97.48%. The vast majority of our patients 95.8% were not postmenopausal. The multigravidas were the most represented, i.e. 37.50% with a large part of the pauciparous 41.29%. In our patients, 96.64% had a clinical symptom on their fibroid with the main reason for consultation being the sensation of a pelvic mass in 97.48%. We recorded three cases of infertility as associated factors. Ultrasound was performed in all patients. The location of the myxomatous nuclei was subserosal in the majority in 42.86% and with multiple nodules in 84.85% of cases. The main indication for myomectomy was the failure of medical treatment in 86.49% of cases. Surgical treatment was mainly a myomectomy 93.30%, a hysterectomy was indicated in 6.70%. No cases of death were recorded. Conclusion: Uterine fibroid is a gynecologic

关键词： Myomas Surgery Myomectomy

Experimental Validation of Light Cable-Driven elbow-Assisting Device L-CADel Design

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Journal of Bionic Engineering 2022年第2期19卷 416-428页

作者： med Amine Laribi Marco Ceccarelli Juan sandoval Matteo Bottin Giulio Rosati Department GMSC Pprime InstituteCNRS-University of Poitiers-ENSMAUPR 334686073 PoitiersFrance Department of Industrial Engineering University of Rome Tor Vergata00133 RomeItaly Department of Industrial Engineering University of Padova35122 PaduaItaly

This paper presents a new design of CADel,a cable-driven elbow-assisting device,with light weighting and control *** new device design is appropriate to be more portable and user-oriented solution,presenting additional facilities with respect to the original *** of potential benefits of improved portability can be envisaged in the possibility of house and hospital usage keeping social distancing while allowing rehabilitation treatments even during a pandemic *** attention has been devoted to design main mechatronic components by developing specific kinematics *** design process includes an implementation of specific control hardware and *** kinematic model of the new design is formulated and features are evaluated through numerical simulations and experimental *** evaluation from original design highlights the proposed improvements mainly in terms of comfort,portability and user-oriented operation.

关键词： Rehabilitation robotics medical devices Design Simulations Cable-driven parallel robot Control

An Experimental Analysis of Overcoming Obstacle in Human Walking

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Journal of Bionic Engineering 2014年第4期11卷 497-505页

作者： Tao Li Marco Ceccarelli Minzhou Luo med Amine Laribi said Zeghloul Institute of Advanced Manufacturing Technology Hefei Institutes of Physical Science Chinese Academy of Sciences Changzhou 213164 P. R. China Laboratory of Robotics and Mechatronics University of Cassino and South Latium Cassino 03043 Italy Institute PPRIME- DGMSC CNRS-University of Poitiers- ENSMA 15 Rue de l'Hotel Dieu 86000 Poitiers France

In this paper, an experimental analysis of overcoming obstacle in human walking is carried out by means of a motion capture system. In the experiment, the lower body of an adult human is divided into seven segments, and three markers are pasted to each segment with the aim to obtain moving trajectory and to calculate joint variation during walking. Moreover, kinematic data in terms of displacement, velocity and acceleration are acquired as well. In addition, ground reaction forces are measured using force sensors. Based on the experimental results, features of overcoming obstacle in human walking are ana- lyzed. Experimental results show that the reason which leads to smooth walking can be identified as that the human has slight movement in the vertical direction during walking; the reason that human locomotion uses gravity effectively can be identified as that feet rotate around the toe joints during toe-off phase aiming at using gravitational potential energy to provide propulsion for swing phase. Furthermore, both normal walking gait and obstacle overcoming gait are characterized in a form that can provide necessary knowledge and useful databases for the implementation of motion planning and gait planning towards overcoming obstacle for humanoid robots.

关键词： human locomotion overcoming obstacle walking gait biped robot motion capture

Design Study of a Cable-based Gait Training Machine

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Journal of Bionic Engineering 2017年第2期14卷 232-244页

作者： Houssein Lamine med Amine Laribi sami Bennour Lotfi Romdhane said Zeghloul Mechanical Laboratory of Sousse (LMS) National Engineering School of Sousse University of Sousse Sousse 4000 Tunisia Department of GMSC Pprime Institute CNRS ENSMA University of Poitiers UPR 3346 France Mechanical Engineering Department American University of Sharjah PO Box 26666 Sharjah United Arab Emirates

This paper deals with a design approach of a gait training machine based on a quantitative gait analysis. The proposed training machine is composed of a body weight support device and a cable-driven parallel robot. This paper is focused on the cable-driven robot, which controls the pose of the lower limb through an orthosis placed on the patient＇s leg. The cable robot reproduces a normal gait movement through the motion of the orthosis. A motion capture system is used to perform the quantitative analysis of a normal gait, which will be used as an input to the inverse dynamic model of the cable robot. By means of an optimization algorithm, the optimal design parameters, which minimize the tensions in the cables, are determined. Two constraints are considered, i.e., a non-negative tension in the cables at all times, and a free cable/end-effector collision. Once the optimal solution is computed, a power analysis is carried out in order to size the robot actuators. The proposed approach can be easily extended for the design study of a similar type of cable robots.

关键词： gait rehabilitation cable-driven robots body weight support system design optimization