35 research outputs found
Electrical spin injection and detection in Germanium using three terminal geometry
In this letter, we report on successful electrical spin injection and
detection in \textit{n}-type germanium-on-insulator (GOI) using a
Co/Py/AlO spin injector and 3-terminal non-local measurements. We
observe an enhanced spin accumulation signal of the order of 1 meV consistent
with the sequential tunneling process via interface states in the vicinity of
the AlO/Ge interface. This spin signal is further observable up to
220 K. Moreover, the presence of a strong \textit{inverted} Hanle effect points
at the influence of random fields arising from interface roughness on the
injected spins.Comment: 4 pages, 3 figure
Accelerating Surgical Robotics Research: A Review of 10 Years With the da Vinci Research Kit
Robotic-assisted surgery is now well-established in clinical practice and has
become the gold standard clinical treatment option for several clinical
indications. The field of robotic-assisted surgery is expected to grow
substantially in the next decade with a range of new robotic devices emerging
to address unmet clinical needs across different specialities. A vibrant
surgical robotics research community is pivotal for conceptualizing such new
systems as well as for developing and training the engineers and scientists to
translate them into practice. The da Vinci Research Kit (dVRK), an academic and
industry collaborative effort to re-purpose decommissioned da Vinci surgical
systems (Intuitive Surgical Inc, CA, USA) as a research platform for surgical
robotics research, has been a key initiative for addressing a barrier to entry
for new research groups in surgical robotics. In this paper, we present an
extensive review of the publications that have been facilitated by the dVRK
over the past decade. We classify research efforts into different categories
and outline some of the major challenges and needs for the robotics community
to maintain this initiative and build upon it
A Collision Model for Rigid and Deformable Bodies
In this paper, we describe models and algorithms designed to produce efficient and physically consistent dynamic simulations. These models and algorithms have been implemented in a unique framework, modeling both deformations and contacts through visco-elastic relations. Since this model of interaction (known as "penalty based") is much debated, we present it in detail. Indeed, the "penalty" based model is said to have two major drawbacks : the difficulty in - determining visco-elastic parameters and in - choosing the computation time step. We present a solution for both problems based on physical concepts. Finally, we will show results comparing real data, "impulse" based simulation and "penalty" based simulation. Keywords --- Dynamic simulation, collision model, deformable bodies, penalty model. Contribution of the paper --- The contributions of this paper are an indepth study of the different problems raised by the penalty model of collision, an automatic way to identify the param..
A Collision Model for Deformable Bodies
In this paper, we describe models and algorithms designed to produce efficient and physically consistent dynamic simulations. These models and algorithms have been implemented in a unique framework, modeling both deformations and contacts through visco-elastic relations. Since this model of interaction (known as "penalty based") is much debated, we present a detailed study of this model. Indeed, the "penalty" based model is supposed to have two major drawbacks : - determining the visco-elastic parameters and - choosing the computation time step. We present a solution for both problems based on physical concepts. Finally, we will present results comparing real data, "impulse" based simulation and "penalty" based simulation. Keywords --- collision, interactions, deformable-objects, rigid-body-mechanics, dynamic-modelling, parameter-identification, animation, simulation, virtual-reality. Acknowledgements --- this work was partially supported by the France Berkeley Fund. A Collision Mo..
Tuning the electrostatic properties of silicon-on-insulating multilayer (SOIM) structures
International audienc
Bias controlled electrostrictive longitudinal resonance in X-cut lithium niobate thin films resonator
International audienceIn this letter, we show that a longitudinal acoustic wave can be generated in X-cut LiNbO(3) (LNO) thin films when a voltage bias is superimposed to the radio frequency signal. Although there is normally no coupling of this wave in X-cut LNO, its electrostrictive behavior combined with bias reaching 3.9 MV/cm induces an electromechanical coupling around 11%. This experiment was performed without acoustic isolation with the LNO substrate (high overtone bulk acoustic resonator configuration)
Surface Contact and Reaction Force Models for Laparoscopic Simulation
In surgery simulation, most existing methods assume that the contact between a virtual instrument and a soft tissue model occur at a single point. However, there is a gross approximation when simulating laparoscopic procedures since the instrument shaft is used in several surgical tasks. In this paper, we propose a new algorithm for modeling the collision response of a soft tissue when interacting with a volumetric virtual instrument involving both the shaft and the tip of the instrument. Th