Mariana Costea
@tuiasi.ro
Faculty of Industrial Design and Business Management
Gheorghe Asachi Technical University of Iasi
Scopus Publications
Scopus Publications
Arina Seul, Aura Mihai, Mariana Costea, Alexandra Bodoga, and Antonela Curteza
MDPI AG
The objective of this study was to analyse the influence of materials and their position within the upper assembly on the behaviour of casual footwear using finite element simulation tools. The study was carried out on three models of casual footwear, which are identical in terms of design lines, varying only in the materials of the upper assembly, namely calfskin leather (M1), knitted fabric (M2), and combination of knitted fabric and calfskin leather (M3). The footwear models were designed according to the design constraints specific to casual footwear. The foot was reconstructed based on the shoe last obtained based on anthropometric data. Material definition, 3D models editing, setting up analysis conditions, and constraints were performed using the Ansys 17.2 software. Gait biomechanics were taken into account to define the loading model, force distribution, force values, and constraints. The study evaluates footwear behaviour in terms of directional deformation (Z axis), equivalent von Mises stress, and equivalent elastic strain distribution. This paper explores a methodology that has the potential to enhance the footwear design and manufacturing process, providing designers with information about the deformations and stress distribution on upper parts of the footwear product.
MARIANA COSTEA, ARINA SEUL, and AURA MIHAI
The National Research and Development Institute for Textiles and Leather
The paper presents experimental research on the slit tear resistance of leather used for producing upholstery. A finite element analysis is done by simulating the product's behaviour, considering different factors and parameters, and materials are classified according to the normal stress results. The maximum force exerted during the tearing of the specimen has been observed at the SATRA tensile testing machine, with STM 466ST attachment and digital software control. The load at break, the extension at break, Young's Modulus, and the load-distance graphs were registered and the medium values were calculated. The Taguchi method based on orthogonal arrays was used to maximize the material characteristics significant for this type of analysis.
Mariana Costea, Aura Mihai, and Arina Seul
Springer International Publishing
Arina Seul, Diana-Roxana Viziteu, Aura Mihai, Antonela Curteza, and Mariana Costea
Springer International Publishing
Aura Mihai, Arina Seul, Antonela Curteza, and Mariana Costea
MDPI AG
This paper aimed to define two critical mechanical properties of leather—Young’s modulus and Poisson ratio—essential to the virtual simulation of the behaviour of the footwear uppers against the manufacturing operations of stitching and perforating. The following technological aspects were considered to analyse the materials from manufacturing conditions point of view: the number of layers (one layer and two layers), the nature of the materials used for uppers subgroups (calfskin-outer upper, sheep leather-lining, polyester knitted fabric-lining), the overlapping width in the stitching area, the number of parallel stitches (single stitch and double stitch), the punching interval and the type of perforations (simple and with eyelets), resulting in nine kinds of samples. Furthermore, the elasticity (Young’s modulus) and lateral contraction (Poisson’s ratio) were calculated during the tensile strength analysis performed on the SATRA STM 466 equipment. Both mechanical parameters are essential to simulate the behaviour of the virtual footwear prototypes in various conditions.
Angela Danila, Mariana Costea, Lenuta Profire, Cristina Mihaela Rimbu, Mihaela Baican, Florentina Lupascu, Simona-Maria Tatarusanu, Bianca-Stefania Profire, and Emil-Ioan Muresan
MDPI AG
This study presents the production, characterization, and application of celandine (Chelidonium majus L.) extracts (aqueous, acidic, alcoholic, and ultrasound) on wool fibers and their characterization. The study aims to obtain an ecologically dyed wool support that possesses biocompatible and antimicrobial activities. The plant extracts were characterized based on pH, total polyphenol content, and berberine content. Ecologically dyed wool supports were characterized based on scanning electron microscopy, levelness index, color measurements, contact angle indirect biocompatibility, and antibacterial analysis. According to the obtained results, celandine extract can be considered a potential candidate for the sustainable dyeing and functionalization of wool fibers.
Mariana COSTEA, Aura MIHAI, and Arina SEUL
Leather and Footwear Research Institute (INCDTP-ICPI)
Designing and manufacturing personalized lasts are the first steps in obtaining the right fitted footwear for various users, especially for sports or/and medical purposes. The accurate dimensional relationship between foot and last represents the key element for this activity. The critical shape of the last should always be determined by the shape of the foot and the cumulative relationship between lengths, widths, heights and girths, whatever method is used. Some corrections and constraints must always be considered because the shoe-last is not identical to the foot. The foot anthropometric measurements are modified based on biomechanical constraints and technological limitations and they are interactively transformed into last’s dimensions by using 3D modelling. The present study brings together the modern scanning technique with the new methodology for modifying a reference last, and it is aimed to explore the philosophy of re-designing functional lasts. It also tests and highlights the limits of the actual methodology for shoe-last virtual prototyping based on anthropometric data acquired from a commercially available 3D foot scanning system.
Mariana COSTEA, Arina SEUL, and Aura MIHAI
Leather and Footwear Research Institute (INCDTP-ICPI)
Nowadays, one of the most critical health problems among young people is obesity. Because teenagers are still in the growing process, the foot shape and plantar footprints are very important to be analysed and potential problems to be identified. Young adulthood is a risky period for the development of obesity. This study aims to analyse the plantar footprints, the biomechanical parameters obtained through plantar pressure measurements, and the 3D shape of the foot and anthropometrical parameters obtained from scanning. By comparing the results, both feet have been demonstrated to be high arched, as well as high pressures were identified and differences from left to the right foot. With these results, prophylactic footwear and components can be designed, adapted to the subject’s feet.
Mariana COSTEA, Arina SEUL, and Aura MIHAI
Leather and Footwear Research Institute (INCDTP-ICPI)
As each person is different in terms of conformation of the foot and temporal and spatial peculiarities of the individual gait pattern, an extended biomechanical analysis was performed for four categories of foot identified by the authors in a previous research study, namely normal, pes cavus (high arched), pes planus (flat) and hallux-valgus foot, in the case of young people aged 20-30 years. A representative case study was selected and the plantar pressures obtained in dynamics were analysed, following the next sequence: framing the subject in the appropriate category, simultaneous visualisation of the footprint for the left and right foot, impulse analysis, recording the variation of plantar pressures and the forces exerted on the foot as a function of time, calculating the percentage values of balance on the rear-foot, heel and medial areas, positioning of the foot axis according to the direction of movement, identification of individual characteristics of walking phases and their temporal / spatial characterisation parameters, highlighting the hysteresis for heel and rear-foot areas, recommendations for the application of orthotic devices. These results are significant in the modelling and design of the bottom shoe assembly, thus proposing solutions for balancing the pressures on the plantar surface by choosing the appropriate dimensional and shape characteristics of the components of this assembly.
Mariana Costea, Aura Mihai, Arina Seul, and Bogdan Sarghie
ADL Romania
This article approaches the piloting stage of 42 trainees involved on MOOC courses for 3D CAD Footwear Developer, developed under Skills 4 Smart TCLF project. S4TCLF it is a project oriented to enhance the modernisation and competitiveness of the EU Textile, Clothing, Leather, and Footwear industry, through the development of a sustainable upskilling and reskilling strategy, which is supported by a communication campaign to attract social, economic and political actors. The project consortium is made from 22 partners within 9 European countries. The 3D CAD Footwear Developer is one of the 8 qualification profiles for which a training course was developed in our European partnership. The course responds to the industry needs and fulfil educational requirements by tackling knowledge and skills related to the footwear product design and styling process, manufacturing stages and technologies, 3D CAD modelling and virtual prototyping, 2D CAD pattern engineering, 3D/2D CAD of lasts, soles and heel, which all together correspond to the level 5 of the European Qualification Framework (EQF). The MOOC courses for 3D CAD Footwear Developer were published on the Iversity learning platform, part of the Springer Nature. A chapter of this course is structured in 3-5 video lectures supported by audio voice. At the end of the chapter an assignment task is proposed to be solved in order to continue with the next chapter/unit. The guided trainees were questioned and assessed by the S4TCLF project staff at different times. The aim of the piloting session was to obtain feedback and to assess the added value of the teaching materials.
Arina Seul, Aura Mihai, Antonela Curteza, and Mariana Costea
ADL Romania
Finite Element Analysis (FEA) is a numerical method widely used in industry, research, and education fields. FEA exploits the properties and dimensions of the model discretised in a series of small regions called finite elements linked together at specific points which are called nodes. This paper demonstrates how the FEA could be used in footwear engineering education as a sustainable tool to predict the designed product's behaviour before its manufacturing. FEA-based simulations have substantial potential in footwear engineering training and education as it allows the students/designer performing static and dynamic analyses to represent the interaction between ground-sole-footwear-foot by analysing the shoe's design parameters' effects on the foot's load transfer. Based on the Finite Element Method (FEM) principles, a methodology for investigating footwear behaviour during normal walking is proposed, including preparatory, pre-processing, analysis, and post-processing stages needed to perform an FEA simulation. This part of the study explains the preparing and pre-processing steps: choosing equipment and software and performing the simulation by modelling and editing the geometry, explaining the role of materials and defining their properties. The pre-processing stages presented in this paper are essential for preparing the simulation process. The 3D geometry and materials influence the accuracy of the FE model and improve the analysis efficiency in engineering applications. Three models of the same constructive type, namely Derby shoe, show the herby described procedure. For these three models, the bar stitch's position varies in a vertical direction, and the material's properties are specified: foot, sole, uppers and bar stitch.
Arina SEUL, Aura MIHAI, Antonela CURTEZA, Mariana COSTEA, and Bogdan SÂRGHIE
Leather and Footwear Research Institute (INCDTP-ICPI)
The biomechanical analysis allows to understand the normal and pathological gait, the mechanics of neuromuscular control, and last but not least, allows the visualisation of the effects of footwear on human gait or feet. Biomechanical analyses are very important for the footwear development process, as they can identify the incorrect loading of the foot or the incorrect gait pattern, thus avoiding the occurrence of deformations. This paper aims to create an average representative model of barefoot loading based on an extended group of participants by applying an optimal procedure for measuring biomechanical parameters. The variation of four basic biomechanical parameters, namely force, pressure, contact time and contact area, was measured using a pressure platform and a specialised software system. The data was collected from 32 healthy females, without particularities regarding foot health and the practice of performance sports, aged between 18 and 30 years, divided into three size groups – 36, 37 and 38. The T-Student test was applied to verify if there are significant differences between the left and right foot. Statistical indicators for each parameter were calculated, in order to characterize and establish the degree of variation of the obtained values, as follows: mean, standard deviation, minimum and maximum values, the amplitude of variation and coefficient of variation (CV). The study results confirm that the obtained mean values can be used as input data to load the foot and perform virtual simulations of footwear products.
Bogdan Sarghie
Stef92 Technology
Mariana Costea
Stef92 Technology
Bogdan Sarghie, Aura Mihai, Mariana Costea, and Elena Rezuş
Elsevier BV
Mariana Costea, Bogdan Sarghie, Aura Mihai, and Elena Rezus
Elsevier BV
Ana Maria Vasilescu, Dana Corina Deselnicu, Mirela Pantazi, Aura Mihai, Mariana Costea, Bogdan Sarghie, Ioan Prada, Despina Gherman, and Constantin Ştefan Petrescu
INCDTP - Division: Leather and Footwear Research Institute, Bucharest, RO
ANA MARIA VASILESCU, DANA CORINA DESELNICU, MIRELA PANTAZI, AURA MIHAI, MARIANA COSTEA, BOGDAN SÂRGHIE, IOAN PRADA, DESPINA GHERMAN, CONSTANTIN ŞTEFAN PETRESCU INCDTP Division Leather and Footwear Research Institute, 93 Ion Minulescu St., sector 3, Bucharest, Romania, icpi@icpi.ro Politehnica University of Bucharest “Gheorghe Asachi” Technical University of Iasi, Faculty of Textile, Leather and Industrial Management “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania KFP PROD IMPEX SRL
Mariana Costea, Bogdan Sarghie, Aura Mihai, and Elena Rezus
INCDTP - Division: Leather and Footwear Research Institute, Bucharest, RO
This paper approaches the relationship between obesity and foot disorders, an important topic in designing and producing preventive or palliative strategies to improve the quality of life for the elders. In spite the growth of old people, they are constrained to accept the footwear that the market is offering, which doesn’t meet their special requirements in case of feet parameters. The analyzed sample consisted in 67 women, aged between 52-84 years old. By comparing the values of body mass index for the analyzed group it is demonstrated that with age, the weight increases for a significant number of women, going from overweight to obese. The authors performed as well, a descriptive statistics and a Pearson correlation between the body mass index and several plantar footprints parameters obtained in a previous research. As an important instrument, the body mass index can be used by footwear producers to modify and customize the last and the elderly shoes. The results of this study are important in various stages of producing footwear, highly adapted to the needs of different pathologies for the elderly consumers.
Ana Maria Vasilescu, Dana Corina Deselnicu, Mirela Pantazi, Despina Gherman, Ioan Prada, Aura Mihai, Mariana Costea, Bogdan Sarghie, and Constantin Ştefan Petrescu
INCDTP - Division: Leather and Footwear Research Institute, Bucharest, RO
ANA MARIA VASILESCU, DANA CORINA DESELNICU, MIRELA PANTAZI, DESPINA GHERMAN, IOAN PRADA, AURA MIHAI, MARIANA COSTEA, BOGDAN SÂRGHIE, CONSTANTIN ŞTEFAN PETRESCU INCDTP Division Leather and Footwear Research Institute, 93 Ion Minulescu St., sector 3, Bucharest, Romania, icpi@icpi.ro Politehnica University of Bucharest “Carol Davila” University of Medicine and Pharmacy, Bucharest, Romania “Gheorghe Asachi” Technical University of Iasi, Faculty of Textile, Leather and Industrial Management KFP PROD IMPEX SRL
Mariana Costea and Aura Mihai
Leather and Footwear Research Institute (INCDTP-ICPI)
COMPARATIVE ANALYSIS OF DYNAMIC PLANTAR PRESSURE DISTRIBUTION ON DIFFERENT AREAS OF THE FOOT ABSTRACT. The plantar distribution between the foot and the contact surface provides valuable information about the foot's structure and functions. The plantar footprints were taken from 60 young women, aged between 20-30 and their foot typology was established by the authors in a previous study. The average values of the plantar pressures recorded on ten foot segments, in case of the four groups: normal foot, high arched foot, flat foot and Hallux-Valgus foot were analyzed in the present study. By comparing the pressures for the four identified groups, it was demonstrated that there are no significant differences between subjects, the maximum values being registered on the third metatarsal head bone, followed by the second metatarsal head bone and the heel. The findings of a Pearson correlation analysis demonstrate that some pressure areas are directly proportional to others (like for example toe areas with first, second, fourth metatarsal head bones and median area of the foot) and other pressure areas are indirectly proportional to others (like for example lateral heel, with second to fifth toe). An important result of the performed analysis is the negative correlation between toe area and the third and fifth metatarsals head bones. Therefore, when creating the footwear bottom components, the designer should use different materials and structures and design in order to redistribute the plantar pressures according to areas of the foot.
Aura Mihai, Mariana Costea, Bogdan Sarghie, Esperanza Almodovar Falco, Rosana Perez, Amaya San Martin, Carlos Ferriz, Carlos V. Carvalho, Claudia Azevedo, Lili Pavlinova Pavlova,et al.
Leather and Footwear Research Institute (INCDTP-ICPI)
INGA 3D project - Creative Transfer of Competence in 3D Footwear CAD to VET Professionals aims to transfer and extend innovative software solutions and 3D technologies for Footwear Computer Aided Design. The project brings together universities, research and training centres, adult education providers and IT companies from Romania, Spain, Portugal, and UK. The project products introduce innovative solutions for e-learning in order to test and to validate new teaching methodologies and approaches suitable for vocational training. The INGA 3D training content, its supportive guide as well as the online learning platform was designed, developed, tested and evaluated in line with the best practices identified by partners in their institutions, countries and elsewhere in Europe. INGA 3D project contributes to developing skills and competencies of VET teachers, trainers, tutors, in order to face the future challenges raised by the necessity of adding to the current curricula in VET institutions ICT skill sets that will enable their graduates to work with highly specialized footwear CAD technologies.
Mariana Driscu and Mariana Costea
Leather and Footwear Research Institute (INCDTP-ICPI)
In this paper the authors present a method of modelling the shoe last shape, namely the dimensional changes in order to produce a variety of footwear products for any category of users. For this, techniques were used to model the last in work sequences of Delcam Crispin 3D application. Using specific tools of this application, modules Model Tracer and Last Maker, this paper presents techniques to create a new shoe last. One can study new shoe lasts compared to the initial ones using the Comparing function. The method for creating new lasts is useful for footwear manufacturers who can always find the shoe last according to their product or can create a new last, similar in shape or different shape from the original one.
Mariana Costea, Ana Maria Vasilescu, Guillaume Hortal, and Aura Mihai
Leather and Footwear Research Institute (INCDTP-ICPI)
Bogdan Sarghie, Mariana Costea, and Aura Mihai
Leather and Footwear Research Institute (INCDTP-ICPI)
The article presents a method of designing templates for modelling shoe lasts, according to specific anthropometrical dimensions of a subject's foot, employed as military personnel. The subject's peculiarity lies in the type of professional activity that he is carrying out; the lower limbs have a much greater risk of injury and there is the need to prevent such problems by using special footwear, which will not restrict the conduct of his military activities. The design of last's templates consists in creating a geometrical construction based on the dimensional characteristics of the subject's feet. Using software such as Delcam Engineer and Last Maker new techniques for modelling shoe lasts were developed. The advantages of the presented method are represented by the decreased time of last's design and the accuracy of the results. Applying this method to a larger scale enables its development and allows footwear manufacturers to achieve a diverse range of products, faster and at lower costs than current possibilities.