Reliable robotic handovers through tactile sensing

Joint manipulation and object exchange are common in many everyday scenarios. Although they are trivial tasks for humans, they are still very challenging for robots. Existing approaches for robot-to-human object handover assume that there is no fault during the transfer. However, unintentional perturbation forces can be occasionally applied to the object, resulting in the robot and the object being damaged, for example by being dropped. In this paper we present a novel approach to handover objects in a reliable manner while ensuring the safety of the robot and the object. Relying on tactile sensing, the system uses an effort controller to adapt the grasp forces in the presence of perturbations. Moreover, the proposed approach identifies a perturbation being applied on the object. When a perturbation event is detected, the algorithm classifies the direction of the pulling forces to decide whether to release it or not. The reliable handover system was implemented using a Shadow Robot hand equipped with BioTAC tactile sensors. Our results show that the system correctly adapts to the forces applied on the object to maintain the grasp and only releases the object if the human receiver pulls in the right direction

Multimodal material identification through recursive tactile sensing

Tactile sensing has recently been used in robotics for object identification, grasping, and material identification. Although human tactile sensing is multimodal, existing material recognition approaches use vibration information only. Moreover, material identification through tactile sensing can be solved as an continuous process, yet state of the art approaches use a batch approach where readings are taken for at least one second. This work proposes a recursive multimodal (vibration and thermal) tactile material identification approach. Using the frequency response of the vibration induced by the material and a set of thermal features, we show that it is possible to accurately identify materials in less than half a second. We conducted an exhaustive comparison of our approach with commonly used vibration descriptors and machine learning algorithms for material identification such as k-Nearest Neighbour, Artificial Neural Network and Support Vector Machines. Experimental results show that our approach identifies materials faster than existing techniques and increase the classification accuracy when multiple sensor modalities are used

SORGIN: A Software Framework For Behavior Control Implementation

This paper describes the software framework that has been developed and that it is being used to build a control architecture for the navigation of a B21 mobile robot. The subsumption architecture and the multi-agent based controller architectures are analyzed and a software framework named SORGIN is presented as a structured programming tool that allows to deal with the complexity of mobile robotic systems. We show how a task that performs safe wandering with a privileged compass orientation has been defined using di#erent behavior bricks in the SORGIN framework

Natural Landmark Based Navigation

The work described in this paper presents a goal oriented navigation system in a behavior-based manner. The main contributions are, in first place the in-depth study of local navigation strategies and, on the other hand, the use of natural landmarks, namely corridors and emergency exit panels. Eliminating the centralized control of modules the system performs the task as a result of the combination of many relatively simple and light weight behaviors that run concurrently

Electroacupuntura en un caso de neuralgia postherpética con afectación de la rama oftálmica del V par craneal

Postherpetic neuralgia consists of chronic neuropathic pain that appears as a complication of varicella-zoster virus infection and is characterized by intense and episodic pain. The treatment of choice is pharmacological but adequate therapeutic response is not always achieved, either due to drug intolerance or to inadequate pain control. We report the case of a woman with postherpetic neuralgia affecting the left ophthalmic branch of the trigeminal nerve, in whom distinct drug treatments failed to achieve adequate pain control. Given this situation, electroacupuncture sessions were started, combined with pharmacological therapy. The frequency and intensity of the pain exacerbations progressively diminished, allowing drug treatment to be discontinued. Electroacupuncture can constitute a therapeutic alternative in patients with drug intolerance or inadequate control of neuropathic pain with pharmacological treatment.Neuralgia postherpética: cuadro de dolor neuropático crónico que aparece como complicación de una infección por el virus de la varicela zóster. La clínica se caracteriza por un dolor intenso y episódico. El tratamiento de elección es farmacológico, pero en un porcentaje de pacientes no se consigue una adecuada respuesta terapéutica, bien por intolerancia a los fármacos bien por inadecuado control del dolor. Se presenta el caso clínico de una paciente con una neuralgia postherpética que afecta a la rama oftálmica izquierda del V par craneal, en la cual no conseguimos un adecuado manejo del cuadro doloroso tras probar diferentes pautas farmacológicas. Ante esta situación, se inició sesiones de electroacupuntura combinadas con fármacos. Se obtuvo una mejoría progresiva de las crisis dolorosas en intensidad y frecuencia, lo que permitió la supresión del tratamiento farmacológico. Alternativa terapéutica a pacientes que no toleran los tratamientos farmacológicos para su dolor neuropático o cuando éstos son ineficaces