Vision-based haptic feedback for remote micromanipulation in-SEM environment.

International audienceThis paper presents an intuitive environment for remote micromanipulation composed of both haptic feedback and virtual reconstruction of the scene. To enable non expert users to perform complex teleoperated micromanipulation tasks it is of utmost importance to provide them with information about the 3D relative positions of the objects and the tools. Haptic feedback is an intuitive way to transmit such information. Since position sensors are not available at this scale, visual feedback is used to derive information about the scene. In this work, three different techniques are implemented, evaluated and compared to derive the object positions from scanning electron microscope images. The modified correlation matching with generated template algorithm is accurate and provides reliable detection of objects. To track the tool, a marker based approach is chosen since fast detection is required for stable haptic feedback. Information derived from these algorithms is used to propose an intuitive remote manipulation system, that enables users situated in geographically distant sites to benefit from specific equipments such as SEMs. Stability of the haptic feedback is ensured by the minimization of the delays, the computational efficiency of vision algorithms and the proper tuning of the haptic coupling. Virtual guides are proposed to avoid any involuntary collisions between the tool and the objects. This approach is validated by a teleoperation involving melamine microspheres with a diameter of less than 2 m between Paris, France and Oldenburg, Germany

Magnetic Resonance Imaging of Magnetic Particles for Targeted Drug Delivery

ABSTRACT Recently there have been initial investigations towards magnetic resonance imaging (MRI) guided actuation and control of untethered devices inside the human cardiovascular system. This form of therapy has the potential to revolutionize today's treatment of cancer and other diseases by providing an accuracy of targeted drug application far beyond conventional approaches. Additionally it is based on standard MRI hardware and does not require any special or tailored hardware. In this article, we present recent work that is focused on visual feedback for the position control of untethered magnetic devices in the MRI. For reliable recognition and tracking, a thorough understanding of the impact of magnetic material on the process of MRI image acquisition is required. A simulation of the image formation process has been implemented. Additionally, initial experimental results of MRI artifact imaging are presented

Design and Waveform Assessment of a Flexible-Structure-Based Inertia-Drive Motor

This paper reports the mechanical design, waveform investigation and experimental validation of an flexible-structure-based inertia-drive linear motor. The flexible structure is designed and verified with finite element analysis to meet the bandwidth requirement for high-frequency actuation. In order to improve the output velocity, non-resonance low-harmonic driving waveform is implemented and evaluated. Experimental results show that the motor is capable of an output velocity of 2.41 mm/s with the waveform, compared to 0.73 mm/s with the classic saw-tooth waveform actuation. The improvement of the non-resonance low-harmonic waveform for the flexible-structure-based motor is confirmed