Tactile Estimation of Molded Plastic Plates Based on the Estimated Impulse Responses of Mechanoreceptive Units

This study proposes a tactile estimation method of molded plastic plates based on human tactile perception characteristics. Plastic plates are often used in consumer products. The tactile evaluation plays an important role in product development. However, physical quantities not taking into account human tactile perception have been employed in previous tactile estimation procedures. Hence, in this study, we adopted the vibrational thresholds of the mechanoreceptive units—FA I, FA II, SA I and SA II—for stimuli detection and developed a tactile estimation method for plastic plates that clarified the mechanoreceptive units related to tactile sensation. The developed tactile sensor consists of a base and a silicone rubber pad that contains strain gauges in it. We detected vibration during touch by the sensor and calculated the estimation of the firing values of the cutaneous mechanoreceptors, which are the essential data obtained by humans during tactile perception, in comparison to the amplitude spectrum of the vibration with the threshold amplitude of each mechanoreceptive unit. Simultaneously, we calculated the relationship between the normal and tangential forces recorded while the sensor ran over the samples. As a result of stepwise linear regression analysis using these values as explanatory variables, the evaluation scores for Soft were successfully estimated using the firing value of FA II and the relationship between normal/tangential forces, and the evaluation scores for Rough were estimated using the SA I firing value

Artificial Skin in Robotics

Artificial Skin - A comprehensive interface for system-environment interaction - This thesis investigates a multifunctional artificial skin as touch sensitive whole-body cover for robotic systems. To further the evolution from tactile sensors to an implementable artificial skin a general concept for the design process is derived. A standard test procedure is proposed to evaluate the performance. The artificial skin contributes to a safe and intuitive physical human robot interaction

Tactile Estimation of Molded Plastic Plates Based on the Estimated Impulse Responses of Mechanoreceptive Units

This study proposes a tactile estimation method of molded plastic plates based on human tactile perception characteristics. Plastic plates are often used in consumer products. The tactile evaluation plays an important role in product development. However, physical quantities not taking into account human tactile perception have been employed in previous tactile estimation procedures. Hence, in this study, we adopted the vibrational thresholds of the mechanoreceptive units—FA I, FA II, SA I and SA II—for stimuli detection and developed a tactile estimation method for plastic plates that clarified the mechanoreceptive units related to tactile sensation. The developed tactile sensor consists of a base and a silicone rubber pad that contains strain gauges in it. We detected vibration during touch by the sensor and calculated the estimation of the firing values of the cutaneous mechanoreceptors, which are the essential data obtained by humans during tactile perception, in comparison to the amplitude spectrum of the vibration with the threshold amplitude of each mechanoreceptive unit. Simultaneously, we calculated the relationship between the normal and tangential forces recorded while the sensor ran over the samples. As a result of stepwise linear regression analysis using these values as explanatory variables, the evaluation scores for Soft were successfully estimated using the firing value of FA II and the relationship between normal/tangential forces, and the evaluation scores for Rough were estimated using the SA I firing value

Applying safe flooring in housing environments related to the independent elderly : evaluating suitability flooring technology to absorb impact in the event of a fall

Aplicat embargament des de la data de defensa fins el dia 3/6/2022This research has been developed with the intention of investigating a different generation of pavements. Most of the current pavements have the same basic standard characteristics and this ensures that living conditions are comfortable, safe, and pleasant for the majority of citizens. But a small group of pavements is designed with a specific purpose: to reduce injuries related to people's falls to the ground; They are called CF (compliant flooring in English). A detailed study of CF flooring systems is warranted to assess their usability for vulnerable groups such as the elderly. This study is structured in six chapters. The first chapter has dealt mainly with bibliographic studies and statistical data consulted on official and international websites. This section evaluates the importance of the increase in the elderly population, life expectancy, and threats to the safety and health of the elderly, especially, and their secondary effects. The scope of the research has been carried out internationally, in Europe and within Spain, and finally, specifically for Catalonia. The second chapter presents a brief overview of the interior flooring, specifically considering its comfort and safety during use. The importance and direct relationship between the sole of the foot and the gait mechanism with respect to the type of pavement have been verified. Many factors that influence this have been investigated, such as the physics and biomechanics of the body when walking, the kinematics of falls, and the dynamics of impact. In addition, a general description of the behavior of materials for use in pavements has been made to better understand the behavior of CF systems. In addition, the most suitable strategies to cope with falls and reduce injuries are discussed. Examining other products with appreciable energy-absorbing and shock-reducing capabilities has been helpful in the proposed pre-designs, all of which have been made based on numerical analysis and related standards. The third chapter is already dedicated to the study of technology and research on the most suitable CF systems; studies from academic, commercial, and architecture departments, in general, are included. In this section, some standard tests related to the various selected materials are developed and several examples of similar products are studied. The fourth chapter includes field research (on-site) and analysis of case studies. Several notable flooring companies around the world were contacted by mail, specifically examining those products whose manufacturers claimed to be shock absorbers. This part of the investigation was slowed down by the delay in shipments. Once they arrived, a real environment was sought where they could obtain the opinion of the elderly and the personnel assigned to their care. All the practice tests were carried out in a residence for the elderly in Barcelona for about two months, focusing on the study of the current pavements of the center and the current derived problems related to users.This entire process was completed by interviewing users and caregivers with predefined questionnaires. It should be noted that this allowed us to contrast the quantitative characteristics of the study in combination with the elements of qualitative research. Chapter Five deals with the results, discussions, suggestions for installation and improvement of pavement safety in risk areas. Simulations were also carried out on a possible base structure of the pavements with the finite element method (FEM). Chapter six presents guidelines for future developments. The author further investigated the materials and their structure and is presented them as a basis for future technical developments.The author considers that, with more detailed studies, it would be possible to use as CF system other materials, either natural or recycled based on agricultural products, which would increase the diversity of the CF system offer and promote more sustainable architectureEsta investigación se ha desarrollado con la intención de investigar una generación diferente de pavimentos. La mayoría de los actuales pavimentos tienen las mismas características básicas estándar y ello garantiza que las condiciones de vida sean cómodas, seguras y agradables para la mayoría de los ciudadanos. Pero un grupo reducido de pavimentos está diseñado con un propósito específico: reducir las lesiones relacionadas con las caídas al suelo de las personas; son los denominados CF (compliant flooring en inglés). Un estudio detallado de los sistemas de pavimentos CF está justificado para evaluar su posibilidad de uso para grupos vulnerables como los ancianos. Este estudio se estructura en seis capítulos. En el primer capítulo se han abordado principalmente los estudios bibliográficos y datos estadísticos consultados en sitios web oficiales e internacionales. En esta sección se evalúa la importancia del aumento de la población anciana. El ámbito de la investigación se ha realizado a nivel internacional, en Europa y dentro de España, y finalmente, específicamente para Cataluña. El segundo capítulo se presenta una breve panorámica del pavimento interior. Se ha constatado la importancia y relación directa entre la planta del pie y el mecanismo de andar con respecto al tipo de pavimento. Se han investigado muchos factores que influyen en ello. Además, se ha realizado una descripción general del comportamiento de los materiales al uso en pavimentos para comprender mejor el comportamiento de los sistemas de CF. Además, se discuten las estrategias más idóneas para hacer frente a las caídas y reducir las lesiones. Examinar otros productos con apreciables capacidades de amortiguación de energía y reducción de impactos ha sido de gran ayuda en los prediseños propuestos, todos los cuales se han realizado sobre la base de análisis numérico y los estándares relacionados. El tercer capítulo está dedicado ya al estudio de la tecnología y la investigación sobre los sistemas de C más idóneos; se incluyen estudios procedentes de departamentos académicos, comerciales y de arquitectura en general. En esta sección se desarrollan algunas pruebas estándar relacionadas con los diversos materiales seleccionados y se estudian varios ejemplos de productos similares. El cuarto capítulo incluye investigación de campo (in situ) y análisis de estudios de casos. Se contactó por correo con varias empresas notables de pavimentos en todo el mundo, y se examinaron específicamente aquellos productos cuyos fabricantes afirmaban ser amortiguadores. Esta parte de la investigación se vio ralentizada por la demora en los envíos. Una vez llegados se buscó un ámbito real donde poder recabar la opinión de las personas mayores y del personal adscrito a su cuidado. Todas las pruebas prácticas se realizaron en una residencia de ancianos de Barcelona durante unos dos meses, centrándose en el estudio de los actuales pavimentos del centro y los problemas actuales derivados relacionados con los usuarios. Todo este proceso se completó mediante entrevistas a usuarios y cuidadores con cuestionarios predefinidos. El Capítulo Cinco se refiere a los resultados, discusiones, sugerencias para la instalación y mejora de la seguridad del pavimento en áreas de riesgo. También se realizaron simulaciones sobre una posible estructura base de los pavimentos con el método elemento finito (FEM). El capítulo seis presenta directrices para desarrollos futuros. El autor investigó más a fondo sobre los materiales y su estructura, y se presenta como una base para desarrollos técnicos futuros. El autor considera que, con estudios más detallados, sería posible utilizar como CF otros materiales, bien naturales o reciclados a base de productos agrícolas, lo cual aumentaría la diversidad de la oferta de CF y fomentaría la arquitectura más sostenible.Postprint (published version

Tongue-Palate Interaction in Discrete and Sequential Swallowing

Historically, swallowing motor control was thought to involve a central mechanism that generated patterned responses with little use of sensory input. Although increasing evidence of peripheral modulation has altered this concept, our knowledge about the flexibility in deglutitive motor control and performance is incomplete. This study sought to gain a better understanding by examining lingual motor strategies in light of changing bolus properties (volume, consistency) and task demands (discrete vs. sequential swallowing). Specifically, the timing and patterns of tongue-palate contact and the associated changes in tongue shape and action were examined in five normal adults using simultaneous electropalatography (EPG) and ultrasound. Tasks for discrete swallowing included 5 and 30 cc of water, 5 and 30 cc of gelatin, and saliva. Tasks for sequential swallowing involved drinking 200 cc of water at normal and fast rates. Two analysis schemes were used to make timing and percent-contact measurements: segmentation of the EPG time series into four stages (prepropulsion, propulsion, full contact, withdrawal), and compartmentalization of the pseudopalate into six bins (front, central, back, lateral, medial, midline). Results showed little variation in contact pattern as a function of bolus property or subject, suggesting considerable stereotypy in lingual motor strategies for movement sequencing. However, unlike the conventional description, tongue-palate contact during propulsion was multidimensional with two distinct degrees of freedom in the front-to-back and the lateral-to-midline continua. Significant (Q<. 0 I) timing differences were found in that larger and thinner boluses were propelled faster than smaller and thicker ones, and dry swallows had longer full contact than water. For sequential swallowing during continuous drinking, the tongue used faster movement speed and overlapping gestures to meet the task demands, while propulsive contact pattern remained invariant. Thus, the change was not in motor strategies per se but in the timing coordination of the "drink" and "swallow" sequences. A 3-D model of oral lingual action for swallowing was proposed. Clinical implications were discussed. In sum, results of this study support the theory that swallowing motor control includes a peripheral mechanism capable of modulating centrally generated responses, and that the deglutitive motor program has both invariant and variant parameters