55 research outputs found
Articulación con rigidez controlable y dispositivo de medición de fuerza
El objeto de la invención es una articulación (1) con
rigidez controlable y medición de fuerza, comprende
un primer dispositivo (20), que comprende un marco
(4) con una cara curva, conectado con un primer
elemento motor (2), realizando este primer dispositivo
(20) la regulación de la posición de la articulación (1),
y un segundo dispositivo (22) que regula la rigidez de
la articulación (1), que comprende un elemento de
empuje (15) cuyo desplazamiento (D) determina una
pre-compresión de un elemento resistivo (11)
determinando de este modo la rigidez de la
articulación (1), y el primer elemento motor (2)
proporciona un giro al marco (4) tal que una rueda (8)
del segundo dispositivo (22) recorre la cara curva del
marco (4) generando una compresión (C) del
elemento resistivo (11) a través de una barra de
transmisión (7) asociada a dicha rueda (8) y al
elemento resistivo (11)Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad Politécnica de MadridB1 Patente sin examen previ
The AMP-Foot 3, new generation propulsive prosthetic feet with explosive motion characteristics: design and validation
The last decades, rehabilitation has become a challenging context for mechatronical engineering. From the state-of-the-art it is seen that the field of prosthetics offers very promising perspectives to roboticist. Today’s prosthetic feet tend to improve amputee walking experience by delivering the necessary push-off forces while walking. Therefore, several new types of (compliant) actuators are developed in order to fulfill the torque and power requirements of a sound ankle-foot complex with minimized power consumption. At the Vrije Universiteit Brussel, the Robotics and Multibody Mechanics research group puts a lot of effort in the design and development of new bionic feet. In 2013, the Ankle Mimicking Prosthetic (AMP-) Foot 2, as a proof-of-concept, showed the advantage of using the explosive elastic actuator capable of delivering the full ankle torques (
±
120
Nm) and power (
±
250
W) with only a 60 W motor. In this article, the authors present the AMP-Foot 3, using an improved actuation method and using two locking mechanisms for improved energy storage during walking. The article focusses on the mechanical design of the device and validation of its working principle.This work and the publication costs of this article have been funded by the European Commissions 7th Framework Program as part of the project Cyberlegs under grant no. 287894 and by the European Commission ERC Starting grant SPEAR under grant no. 337596.Peer reviewe
An Active Knee Orthesis for the Physical Therapy of NEurological Disorders
This paper presents the design of a new robotic orthotic solution aimed at improving the rehabilitation of a number of neurological disorders (Multiple Sclerosis, Post-Polio and Stroke). These neurological disorders are the most expensive for the European Health Systems, and the personalization of the therapy will contribute to a 47% cost reduction. Most orthotic devices have been evaluated as an aid to in-hospital training and rehabilitation in patients with motor disorders of various origins. The advancement of technology opens the possibility of new active orthoses able to improve function in the usual environment of the patient, providing added benefits to state-of-the-art devices in life quality. The active knee orthosis aims to serve as a basis to justify the prescription and adaptation of robotic orthoses in patients with impaired gait resulting from neurological processes.Peer Reviewe
Control motion approach of a lower limb orthosis to reduce energy consumption
By analysing the dynamic principles of the human gait, an economic gait‐control analysis is performed, and passive elements are included to increase the energy efficiency in the motion control of active orthoses. Traditional orthoses use position patterns from the clinical gait analyses (CGAs) of healthy people, which are then de‐normalized and adjusted to each user. These orthoses maintain a very rigid gait, and their energy cosT is very high, reducing the autonomy of the user. First, to take advantage of the inherent dynamics of the legs, a state machine pattern with different gains in eachstate is applied to reduce the actuator energy consumption. Next, different passive elements, such as springs and brakes in the joints, are analysed to further reduce energy consumption. After an off‐line parameter optimization and a heuristic improvement with genetic algorithms, a reduction in energy consumption of 16.8% is obtained by applying a state machine control pattern, and a reduction of 18.9% is obtained by using passive elements. Finally, by combining both strategies, a more natural gait is obtained, and energy consumption is reduced by 24.6%compared with a pure CGA pattern
Andador con mecanismo de asistencia en operaciones de levantado y sentado de un usuario
Andador (1) con mecanismo de asistencia en
operaciones de levantado y sentado de un usuario
(21) que comprende una estructura de soporte dotada
de medios de desplazamiento (2, 3), un dispositivo de
sujeción (20) del usuario al andador y un sistema de
bloqueo de los medios de desplazamiento, donde la
estructura de soporte comprende al menos un brazo
pivotante (14) que guía al dispositivo de sujeción (20)
del usuario (21), un soporte guía (11) fijado al
andador (1) y que guía al brazo (14) y un módulo de
control (15) que controla el sistema de bloqueo de los
medios de desplazamiento (2,3) y que comprende
medios de selección de un modo de trabajo del
andador seleccionado entre “modo andar” y “modo
sentarse/levantarse”Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad Politécnica de MadridB1 Patente sin examen previ
Identifying ground-robot impedance to improve terrain adaptability in running robots
To date, running robots are still outperformed by animals, but their dynamic behaviour can be described by the same model. This coincidence means that biomechanical studies can reveal much about the adaptability and energy efficiency of walking mechanisms. In particular, animals adjust their leg stiffness to negotiate terrains with different stiffnesses to keep the total leg-ground stiffness constant. In this work, we aim to provide one method to identify ground-robot impedance so that control can be applied to emulate the aforementioned animal behaviour. Experimental results of the method are presented, showing well-differentiated estimations on four different types of terrain. Additionally, an analysis of the convergence time is presented and compared with the contact time of humans while running, indicating that the method is suitable for use at high speeds
Estimating Overall and Cause-Specific Excess Mortality during the COVID-19 Pandemic: Methodological Approaches Compared
During the COVID-19 pandemic, excess mortality has been reported worldwide, but its magnitude has varied depending on methodological differences that hinder between-study comparability. Our aim was to estimate variability attributable to different methods, focusing on specific causes of death with different pre-pandemic trends. Monthly mortality figures observed in 2020 in the Veneto Region (Italy) were compared with those forecasted using: (1) 2018–2019 monthly average number of deaths; (2) 2015–2019 monthly average age-standardized mortality rates; (3) Seasonal Autoregressive Integrated Moving Average (SARIMA) models; (4) Generalized Estimating Equations (GEE) models. We analyzed deaths due to all-causes, circulatory diseases, cancer, and neurologic/mental disorders. Excess all-cause mortality estimates in 2020 across the four approaches were: +17.2% (2018–2019 average number of deaths), +9.5% (five-year average age-standardized rates), +15.2% (SARIMA), and +15.7% (GEE). For circulatory diseases (strong pre-pandemic decreasing trend), estimates were +7.1%, −4.4%, +8.4%, and +7.2%, respectively. Cancer mortality showed no relevant variations (ranging from −1.6% to −0.1%), except for the simple comparison of age-standardized mortality rates (−5.5%). The neurologic/mental disorders (with a pre-pandemic growing trend) estimated excess corresponded to +4.0%/+5.1% based on the first two approaches, while no major change could be detected based on the SARIMA and GEE models (−1.3%/+0.3%). The magnitude of excess mortality varied largely based on the methods applied to forecast mortality figures. The comparison with average age-standardized mortality rates in the previous five years diverged from the other approaches due to the lack of control over pre-existing trends. Differences across other methods were more limited, with GEE models probably representing the most versatile option
Q-ROBOT CAST FOR LADLE AREA: REACHING NEW LEVELS OF AUTOMATION AND SAFETY IN CONTINUOUS CASTING
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The AMP-Foot 3, new generation propulsive prosthetic feet with explosive motion characteristics: design and validation
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