Search

[Resumen] En el campo de la rehabilitación robótica de la marcha, a menudo es necesario controlar los dispositivos robóticos para que sigan trayectorias de referencia específicas similares a las humanas. En los últimos años, se han propuesto varios modelos de generadores de marcha que proporcionan patrones de marcha personalizados ajustables a una serie de alturas y velocidades de marcha. Estos trabajos se desarrollaron centrándose principalmente en dispositivos de rehabilitación de la marcha que controlan las trayectorias angulares de las articulaciones inferiores. Otros dispositivos de rehabilitación similares, como los robots de rehabilitación con efector final que controlan las trayectorias de posición y orientación de sus articulaciones en el espacio cartesiano, no pueden implementarlos fácilmente. En este artículo se propone un nuevo generador de patrones de marcha que genera trayectorias tridimensionales individualizadas para robots de rehabilitación de la marcha. El modelo utiliza predicciones de las trayectorias angulares de las articulaciones, basadas en modelos de regresión multivariable, proporciones antropométricas humanas y modulaciones espaciotemporales para predecir las trayectorias cartesianas de las articulaciones inferiores de la pelvis, la cadera, la rodilla y el tobillo durante la marcha. Las trayectorias reconstruidas se compararon con la cinemática medida de un conjunto de datos de la marcha con 42 participantes que caminaban a 8 velocidades diferentes cada uno. Las trayectorias generadas coincidieron con las medidas con un error medio RMSE de 15,27 mm y coeficiente de correlación R medio de 89% para todos los ejes articulares, lo que sugiere que se trata de una buena solución para su aplicación en dispositivos robóticos de rehabilitación de la marcha con efector final., [Abstract] In the robotic gait rehabilitation field, it is often required to control the robotic devices to follow specific human-like reference trajectories. In the recent years, various gait generator models have been proposed, providing customized gait patterns adjustable to a range of heights and gait speeds. These works were developed focusing mainly on gait rehabilitation devices that control the angular trajectories of the lower joints. Similar rehabilitation devices, such as end-effector rehabilitation robots that control their joint position and orientation trajectories in the Cartesian space cannot easily implement them. In this article, it is proposed a new gait pattern generator that outputs individualized three-dimensional joints' trajectories for gait rehabilitation robots. The algorithm uses joint’s angular trajectories predictions, based on multi-variable regressions-models, human anthropometric proportions and spatiotemporal modulations to predict the cartesian lower joints trajectories of the pelvis, hip, knee and ankle during gait. The reconstructed trajectories were compared to the measured joint kinematics of a gait dataset with 42 participants walking at 8 different velocities each. The predicted trajectories matched the measured ones with an RMSE average error of 15.27mm and mean R coefficient of 89% for all the joints axis, suggesting to be a good solution to be applied in end-effector gait robotic rehabilitation devices.

[Resumen] En la robótica de rehabilitación de la marcha es común controlar los dispositivos siguiendo trayectorias de referencia. Estas trayectorias de referencia consisten en ángulos articulares previamente medidos o generados mediante otros métodos. Normalmente estos dispositivos suelen controlarse con posiciones o velocidades angulares pero existen algunas plataformas que requieren un control tridimensional de la marcha. Es por ello que este artículo presenta un generador de patrones tridimensional dependiente de las dimensiones del usuario y velocidad de la marcha. El algoritmo desarrollado obtiene las trayectorias angulares acordes a la velocidad demandada y las dimensiones de los segmentos del tren inferior acordes a la altura de los pacientes, genera las trayectorias tridimensionales de todas las articulaciones, ajusta estas trayectorias según eventos clave de la marcha para obtener información espaciotemporal de la misma y modular la velocidad de generación de consignas. Este método por tanto aporta un componente extra de flexibilidad y adaptabilidad a las plataformas robóticas ya que permite la modulación tridimensional de la marcha de acuerdo a las características del usuario (dimensiones) y su intencionalidad (velocidad de marcha)., [Abstract] In gait rehabilitation robotics it is common to control devices following reference trajectories. These reference trajectories consist of joint angles previously measured or generated by other methods. Normally these devices are usually controlled with angular positions or velocities but there are some platforms that require a three-dimensional control of the movement. That is why this article presents a three-dimensional pattern generator dependent on the user's dimensions and walking speed. The developed algorithm obtains the angular trajectories according to the speed demanded and the dimensions of the segments of the lower body according to the height of the patients, generates the three-dimensional trajectories of all the joints, adjusts these trajectories according to key gait events to obtain information space-time of the same and modulate the speed of generation of slogans. Therefore, this method provides an extra component of flexibility and adaptability to robotic platforms since it allows the three-dimensional modulation of the gait according to the characteristics of the user (dimensions) and their intention (gait speed).

[Resumen] Avances recientes en el control de exoesqueletos se están centrando en mejorar la asistencia de equilibrio y disminuir la dependencia de las muletas. Sin embargo, métodos apropiados para cuantificar la estabilidad de estos exoesqueletos (y de sus usuarios) aún son escasos. Una evaluación del equilibrio cuantitativa es fundamental para enriquecer el desempeño de los exoesqueletos y su interacción con los seres humanos. En este trabajo presentamos el sistema BenchBalance, una soluci ón para realizar evaluaciones comparativas y reproducibles de equilibrio en exoesqueletos y sus usuarios. Al integrar dos elementos clave (perturbador manual y prenda inteligente), BenchBalance es una herramienta portátil y de bajo coste que proporciona una evaluación cuantitativa relacionada con la reacción y la capacidad de los exoesqueletos portátiles y sus usuarios para responder a perturbaciones externas controladas., [Abstract] Recent advances on the control of exoskeletons are being centered on improving balance support and decreasing the reliance on crutches. However, appropriate methods to quantify the stability of these exoskeletons (and and their users) are still under development. A reliable and reproducible balance assessment is critical to enrich exoskeletons’ performances and their interaction with human beings. In this work we present the BenchBalance system, a benchmarking solution to conduct reproducible balance assessments of exoskeleton and users. Integrating two key elements (manual perturbator and smart garment), BenchBalance is a portable and low-cost tool that provides a quantitative assessment related to the reaction and capacity of wearable exoskeletons and their users to respond to controlled external perturbations.

Recent advances in the control of overground exoskeletons are being centered on improving balance support and decreasing the reliance on crutches. However, appropriate methods to quantify the stability of these exoskeletons (and their users) are still under development. A reliable and reproducible balance assessment is critical to enrich exoskeletons’ performance and their interaction with humans. In this work, we present the BenchBalance system, which is a benchmarking solution to conduct reproducible balance assessments of exoskeletons and their users. Integrating two key elements, i.e., a hand-held perturbator and a smart garment, BenchBalance is a portable and low-cost system that provides a quantitative assessment related to the reaction and capacity of wearable exoskeletons and their users to respond to controlled external perturbations. A software interface is used to guide the experimenter throughout a predefined protocol of measurable perturbations, taking into account antero-posterior and mediolateral responses. In total, the protocol is composed of sixteen perturbation conditions, which vary in magnitude and location while still controlling their orientation. The data acquired by the interface are classified and saved for a subsequent analysis based on synthetic metrics. In this paper, we present a proof of principle of the BenchBalance system with a healthy user in two scenarios: subject not wearing and subject wearing the H2 lower-limb exoskeleton. After a brief training period, the experimenter was able to provide the manual perturbations of the protocol in a consistent and reproducible way. The balance metrics defined within the BenchBalance framework were able to detect differences in performance depending on the perturbation magnitude, location, and the presence or not of the exoskeleton. The BenchBalance system will be integrated at EUROBENCH facilities to benchmark the balance capabilities of wearable exoskeletons and their users.

Tremor is defined as a rhythmic, involuntary oscillatory movement of a body part. Although everyone exhibits a certain degree of tremor, some pathologies lead to very disabling tremors. These pathological tremors constitute the most prevalent movement disorder, and they imply severe difficulties in performing activities of daily living. Although tremors are currently managed through pharmacotherapy or surgery, these treatments present significant associated drawbacks: drugs often induce side effects and show decreased effectiveness over years of use, while surgery is a hazardous procedure for a very low percentage of eligible patients. In this context, recent research demonstrated the feasibility of managing upper limb tremors through wearable technologies that suppress tremors by modifying limb biomechanics or applying counteracting forces. Furthermore, recent experiments with transcutaneous afferent stimulation showed significant tremor attenuation. In this regard, this article reviews the devices developed following these tremor management paradigms, such as robotic exoskeletons, soft robotic exoskeletons, and transcutaneous neurostimulators. These works are presented, and their effectiveness is discussed. The article also evaluates the different metrics used for the validation of these devices and the lack of a standard validation procedure that allows the comparison among them.