Haptic Human Interfaces for Robotic Telemanipulation

Abstract -This paper proposes that there are ultimately only two topi cal tactile feedback generation modalities for haptic human interfaces which allow the human operator to handle either (i) temporary VR-based material replicas of the local geometric and/or force profile at the contact areas of an unlimited set of generic objects that could virtually be handled during the manipulation, or (ii) permanent material replicas of a limited set of typical objects. Examples of tactile human interfaces developed by the authors for telerobotic blind tactile exploration of objects, for telerobotic hapto-visual stylus-style tool manipulation are presented to illustrate the proposed approach. A NN architecture allowing for the modelling of the elastic properties of 3D objects from experimental tactile and range imaging data is also presented

Estimación de la forma de un objeto deformable mediante integración de visión y tacto

Desde hace varias décadas los robots industriales han demostrado su eficiencia para tareas desarrolladas en entornos perfectamente conocidos. No obstante, surgen importantes complicaciones operativas en entornos limitadamente conocidos, y esto dificulta de manera considerable su uso en muchas áreas de interés, limitando la expansión de la robótica. Esta tesis pretende aportar una pequeña contribución a este vasto problema y, para ello, focaliza su estudio sobre un problema concreto: la manipulación robotizada de objetos deformables. La operación sobre objetos rígidos no está exenta de problemas, muchos de ellos derivados de información imperfecta, pero al menos se sabe que la forma de estos objetos permanecerá inalterable cuando se los manipule. Es por ello que el trato con objetos deformables requiere abordar el problema desde una nueva perspectiva que pasa, necesariamente, por el uso de algún modelo del objeto que aporte información sobre su forma en función de la actuación del robot. Las dificultades surgen fundamentalmente por dos motivos: el modelo no es perfecto y la actuación del robot no es totalmente conocida. Esto obliga al uso de información externa con la que poder corregir ambas deficiencias, pero con ello tampoco queda resuelto el problema dado que esa nueva información tampoco es perfecta. Esta tesis aborda el problema de conseguir una buena información sobre la forma de una membrana de caucho natural fijada a una plataforma circular, cuando se la somete a una manipulación robotizada. Para ello se ha diseñado, implementado y validado el modelo exponencial de masas y muelles sobre el que se ha llevado a cabo un completo estudio del comportamiento de la membrana ante diferentes actuaciones del robot. A partir de ahí, y haciendo uso de información sensorial de fuerza, par y visión estereoscópica, se han diseñado, implementado y validado un conjunto de algoritmos de integración sensorial basados en el filtro de partículas y en la fusión probabilística, con los que se ha conseguido obtener una información de suficiente calidad como para operar debidamente.Industrial robots have proven their efficiency for several decades, when they operate in perfectly known environments. However, significant operational complications arise in limitedly known environments, and this difficult significantively its use in many areas of interest, hindering its expansion. This thesis aims to make a small contribution to this vast problem and, for this reason, the study focuses on a specific problem: the robotic manipulation of deformable objects. The operation on rigid objects is not exempt of problems. Many of them arise from an operation with non-perfect information, but at least we know that the shape of these objects remains unchanged when they are handled. But the handling of deformable objects requires the addressing of the problem from a new perspective, which necessarily needs the use of some object model that provides shape information based on the operation of the robot. The fundamental problem arises for two reasons: the model is not perfect and the operation of the robot is not fully known. This requires the use of independent information with which to correct both deficiencies, but even so, the problem is not totally solved because the new information is not perfect. This thesis addresses the problem of getting a proper information about the shape of a natural rubber membrane attached to a circular platform, when such membrane is subjected to a robotic manipulation. To address such problem, the exponential mass-spring model has been is designed, implemented and validated. A complete study has been made about the behavior of the membrane at different operations of the robot. Thereafter, making use of information obtained from force, torque and stereoscopic vision sensors, we have designed, implemented and validated a set of sensory integration algorithms. Such algorithms are based on particle filter and the probabilistic fusion, and it have allowed to obtain an information of sufficient quality to operate properly.Postprint (published version