Search

This work addresses the magnetic-based control of a helical robot and the mitigation of the magnetic forces on its dipole moment during radial steering using rotating permanent magnets. A magnetic system with two synchronized permanent magnets that rotate quasistatically is used to move the helical robot (length and diameter of 12.5 mm and 4 mm, respectively). We experimentally demonstrate that using two synchronized permanent magnets for radial steering of a helical robot achieves higher motion stability, as opposed to propulsion using single rotating dipole field. The two synchronized dipole fields decrease the lateral oscillation (average peak-to-peak amplitude) of the helical robot by 37%, compared to the radial steering using a single dipole field at angular velocity of 31 rad/s. We also show that driving the helical robot using two synchronized rotating magnets achieves average swimming speed of 2.1 mm/s, whereas the single rotating dipole field achieves average swimming speed of 0.4 mm/s at angular velocity of 31 rad/s for the rotating permanent magnets. The proposed configuration of the helical propulsion allows us to decrease the magnetic forces that could cause tissue damage or potential trauma for in vivo applications.

Using Parallel Platforms as Climbing Robots

En este trabajo se presenta el desarrollo de un robot basado en la estructura tensegrity con el fin de realizar tareas de inspección y mantenimiento en tuberías petroleras. Debido a la naturaleza de la aplicación, el robot debe ser capaz de desplazarse verticalmente por el exterior de la tubería. Este tipo de estructura mecánica se caracteriza por su bajo peso y su alta capacidad de adaptación a los diferentes diámetros. La aplicación requiere que el dispositivo desarrollado se desplace a alta velocidad por las tuberías utilizadas en la extracción del petróleo. Cabe destacar que en dichas instalaciones se cuenta con Bombas Electro Sumergibles (BES) y Bombas de Cavidad Progresiva (BCP), ambas muy sensibles a las condiciones adversas del entorno. Consecuentemente se prevé que el robot incorpore una red de sensores específicos para medir aquellas variables que puedan interferir en el funcionamiento normal de las bombas. En este artículo se describen detalladamente las hipótesis de diseño realizadas y la metodología utilizada para el desarrollo del primer prototipo. Finalmente se presentan los resultados obtenidos de dicho desarrollo a través de los cuales se ha podido validar la potencialidad de la aplicación. This paper presents the development of a robot based on tensegrity structure with to perform inspection and maintenance in petroleum pipelines. Due to the nature of application, the robot must be able to move vertically on the outside of the pipe. This type of mechanical structure is characterized by low weight and high capacity to adapt to different diameters. The application requires that the device developed high-speed moving through the pipes used in oil extraction. Note that in these facilities has Submersible Electric Pumps and Progressive Cavity Pumps (PCP), both very sensitive to the environmental conditions, the robot will incorporate sensors to measure variables that may interfere with normal functioning pumps. This article describes in detail the design assumptions made and methodology used to develop the first prototype. Finally, we present the results obtained through the development which has been validated the potential of application.

Objective: In this article, we present the conceptual development of a robotics platform, called ALICE (Assistive Lower Limb Controlled Exoskeleton), for kinetic and kinematic gait characterization. The ALICE platform includes a robotics wearable exoskeleton and an on-board muscle driven simulator to estimate the user’s kinetic parameters. Background: Even when the kinematics patterns of the human gait are well studied and reported in the literature, there exists a considerable intra-subject variability in the kinetics of the movements. ALICE aims to be an advanced mechanical sensor that allows us to compute real-time information of both kinetic and kinematic data, opening up a new personalized rehabilitation concept. Methodology: We developed a full muscle driven simulator in an open source environment and validated it with real gait data obtained from patients diagnosed with multiple sclerosis. After that, we designed, modeled, and controlled a 6 DoF lower limb exoskeleton with inertial measurement units and a position/velocity sensor in each actuator. Significance: This novel concept aims to become a tool for improving the diagnosis of pathological gait and to design personalized robotics rehabilitation therapies. Conclusion: ALICE is the first robotics platform automatically adapted to the kinetic and kinematic gait parameters of each patient.