Search results for "Robotic"
showing 10 items of 636 documents
ART Azzurra Robot Team
1999
Azzurra Robot Team is the result of a joint effort of seven Italian research groups from Univ. of Brescia, Univ. of Genoa, Politecnico of Milano, Univ. of Padua, Univ. of Palermo, Univ. of Parma, Univ. of Roma "La Sapienza", and the Consorzio Padova Ricerche which has provided resources and a set up of the soccer field in its Center in Padua. Our goal at Robocup 1998 has been to provide a exible and low-cost experimental team to make experience before undertaking a larger project. Our long term goal is to foster the development of research and education projects on autonomous mobile robots by exploiting the RoboCup challenge.
Robust Control of Nonlinear Systems: An Unknown Input Observer Based Approach
2023
Questa tesi propone un controllore robusto per sistemi non lineari tramite l'utilizzo di un osservatore ad ingressi sconosciuti. Attraverso un'opportuna riformulazione dinamica del modello, un generico sistema non lineare viene descritto come la somma di due funzioni, la prima lineare e nota e la seconda altamente non lineare e sconosciuta, derivante dalla conoscenza imperfetta del modello dinamico, dei parametri, o di eventuali disturbi esogeni agenti sul sistema etc., modellabili come perturbazioni (disturbi) della funzione lineare. Questa semplificazione consente una vantaggiosa descrizione dinamica del sistema in forma matriciale. Le informazioni necessarie sono stimate attraverso l'uti…
Open-Loop Drug Delivery Strategy to the Cochlea using a Permanent Magnetic Actuator
2018
International audience; The use of robotic devices for drug delivery in sensitive area of the human body is an innovative and reliable solution. Most of them use magnetics fields, to steer micro-nanorobots into diseases locations. In this study, we use a magnetic actuator based on two permanent magnets as an end-effector of a robotic manipulator. The actuator offers the possibility to generate both pushing and pulling forces on the magnetic actuator axis in an open-loop control way. We describe in this paper the robotic drug delivery strategy that we implemented in a 6 degree of freedom robotic manipulator to push and to steer a magnetic microparticle from the round window to the apex of th…
Robotic versus laparoscopic sacrocolpopexy for apical prolapse: a case-control study
2016
The apical prolapse has always been considered the most complex of the defects of the pelvic floor, for both the difficulty of the surgical corrective technique and for the high post-surgical recurrence rate. Today, the laparoscopic sacrocolpopexy can be considered the standard treatment for apical prolapse. In the last years, several author performed robotic sacrocolpopexy, obtaining positive results. So, we developed a case-control study in order to compare the surgical outcome of robotic group with a control group of laparoscopic approach in patients with symptomatic apical pro-lapsed between January 2015 and December 2015 at University Hospital Policlinico “P. Giaccone” and Ospedali Riu…
Selective Actuation and Tomographic Imaging of Swarming Magnetite Nanoparticles
2021
International audience; Micro- and nanomotors have seen substantial progress in recent years for biomedical applications. However, three grand challenges remain: (i) high velocities to overcome the blood flow, (ii) spatially selective control to enable complex navigation, and (iii) integration of a medical, tomographic real-time imaging method to acquire feedback information. Here, we report the combination of active magnetic matter and a medical imaging technique, namely magnetic particle imaging (MPI), which addresses these needs. We synthesize ∼200 nm magnetic nanoparticles and observe a macroscopic, collective effect in a homogeneous magnetic field with a rotating field vector. The nano…
Controlling and learning motor functions
2018
Effective and adaptive motor functions are important for living beings and developing computational and learning mechanisms for roving robots is a crucial aspect in biorobotics. In this chapter we report a new architecture for motor learning to be applied in insect-like walking robots. The proposed model is based on the MB structure previously introduced able to memorize time evolutions of key parameters of the neural motor controller to improve existing motor primitives. The adopted control scheme enables the structure to efficiently cope with goal-oriented behavioural motor tasks. The problem of body-size evaluation is also considered and a model for the parallax-based estimation is provi…
Integration of Gravitational Torques in Cerebellar Pathways Allows for the Dynamic Inverse Computation of Vertical Pointing Movements of a Robot Arm
2008
BackgroundSeveral authors suggested that gravitational forces are centrally represented in the brain for planning, control and sensorimotor predictions of movements. Furthermore, some studies proposed that the cerebellum computes the inverse dynamics (internal inverse model) whereas others suggested that it computes sensorimotor predictions (internal forward model).Methodology/principal findingsThis study proposes a model of cerebellar pathways deduced from both biological and physical constraints. The model learns the dynamic inverse computation of the effect of gravitational torques from its sensorimotor predictions without calculating an explicit inverse computation. By using supervised …
Analysis of motor control and behavior in multi agent systems by means of artificial neural networks
2004
Abstract This article gives a short introduction to Self-Organizing Maps, a particular form of Artificial Neural Networks and shows by some examples, how these approaches can be used in order to analyze and visualize time series data originating from complex systems. The methods shown in this article have originally been developed for the analysis of RoboCup robot soccer games, a special kind of so-called Multi Agent Systems. Although this application has no direct connection to biomechanics, the examples shown here may give an impression of the abilities of Neural Networks in the field of Time Series Analysis in general. Because of the abstractness of the methods, it appears to be very lik…
A Study of the Simulated Evolution of the Spectral Sensitivity of Visual Agent Receptors
2001
In this article we study a model for the evolution of the spectral sensitivity of visual receptors for agents in a continuous virtual environment. The model uses a genetic algorithm (GA) to evolve the agent sensors along with the control of the agents by requiring the agents to solve certain tasks in the simulation environment. The properties of the evolved sensors are analyzed for different scenarios. In particular, it is shown that the GA is able to find a balance between sensor costs and agent performance in such a way that the spectral sensor sensitivity reflects the emission spectrum of the target objects and that the capability of the sensors to evolve can help the agents significantl…
A comparison between a two feedback control loop and a reinforcement learning algorithm for compliant low-cost series elastic actuators
2020
Highly-compliant elastic actuators have become progressively prominent over the last years for a variety of robotic applications. With remarkable shock tolerance, elastic actuators are appropriate for robots operating in unstructured environments. In accordance with this trend, a novel elastic actuator was recently designed by our research group for Serpens, a low-cost, open-source and highly-compliant multi-purpose modular snake robot. To control the newly designed elastic actuators of Serpens, a two-feedback loops position control algorithm was proposed. The inner controller loop is implemented as a model reference adaptive controller (MRAC), while the outer control loop adopts a fuzzy pr…