We describe the design and performance of a hand-held actively stabilized tool to increase accuracy in micro-surgery or other precision manipulation. It removes involuntary motion such as tremor by actuating the tip to counteract the effect of the undesired handle motion. The key components are a three-degree-of-freedom piezoelectric manipulator that has 400 μm range of motion, 1 N force capability, and bandwidth over 100 Hz, and an optical position measurement subsystem that acquires the tool pose with 4 μm resolution at 2000 samples/s. A control system using these components attenuates hand motion by at least 15 dB (a fivefold reduction). By considering the effect of the frequency response of Micron on the human visual feedback loop, we have developed a filter that reduces unintentional motion, yet preserves intuitive eye-hand coordination. We evaluated the effectiveness of Micron by measuring the accuracy of the human/machine system in three simple manipulation tasks. Handheld testing by three eye surgeons and three non-surgeons showed a reduction in position error of between 32% and 52%, depending on the error metric.

Abstract-Recent research has exploited the inherent bending of a bevel-tipped needle during insertion, accomplishing steering of the needle by rotating the needle shaft. Combining this technique with the observation that a straight trajectory can be accomplished by spinning the needle at a constant rate during insertion, this paper presents a novel technique for proportional control of the curvature of the trajectory via duty-cycled spinning of the needle. In order to accommodate this technique to very soft tissues such as the brain, several custom needle prototypes have also been designed in order to increase the steering versatility of the system by maximizing the attainable curvature. The paper describes the needle-steering system and the needle prototypes, and presents preliminary results from tests in an artificial brain tissue substitute.

Abstract-The authors describe a minimally invasive flexible needle-steering system to access deep areas of the brain. The design exploits the inherent bending of a beveled-tip needle when passing through tissue. Precise control of the rotation of the needle allows for an unlimited variety of trajectories. Potential advantages to this system include the possibility of catheter-based therapy delivery within the brain with minimal trauma to surrounding structures, and the ability to navigate around critical cerebral structures to reach deep zones within the brainstem, thalamus or other subcortical regions.

We rigorously present the geometric issues related to binocular imaging. We identify the minimum number and most fundamental conceptual set of parameters needed to define 3D-stereoscopic camera and display systems; the fundamental parameter that is needed to specify a 3D-stereoscopic system but not a monocular system is the pupillary distance. We analyse the constraints that are imposed on the values of the parameters by the requirement that the imagery be geometrically indistinguishable from the reality that would be perceived by the "naked' human visual apparatus. We relate our approach to those employed by several well known textbooks and graphics engines.

Earth science research must bridge the gap between the atmosphere and the ocean to foster understanding of Earth's climate and ecology. Typical ocean sensing is done with satellites or in situ buoys and research ships which are slow to reposition. Cloud cover inhibits study of localized transient phenomena such as Harmful Algal Blooms (HAB). A fleet of extended-deployment surface autonomous vehicles will enable in situ study of characteristics of HAB, coastal pollutants, and related phenomena. We have developed a multiplatform telesupervision architecture that supports adaptive reconfiguration based on environmental sensor inputs. Our system allows the autonomous repositioning of smart sensors for HAB study by networking a fleet of NOAA OASIS (Ocean Atmosphere Sensor Integration System) surface autonomous vehicles. In situ measurements intelligently modify the search for areas of high concentration. Inference Grid and complementary information-theoretic techniques support sensor fusion and analysis. Telesupervision supports sliding autonomy from high-level mission tasking, through vehicle and data monitoring, to teleoperation when direct human interaction is appropriate. This paper reports on experimental results from multi-platform tests conducted in the Chesapeake Bay and in Pittsburgh, Pennsylvania waters using OASIS platforms, autonomous kayaks, and multiple simulated platforms to conduct cooperative sensing of chlorophyll-a and water quality.

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Aircraft flight pressurization/depressurization cycling causes the skin to inflate and deflate, stressing it around the rivets that fasten it to the airframe. The resulting strain, exacerbated by corrosion, drives the growth of initially microscopic cracks. To avoid catastrophe, aircraft are inspected periodically for cracks and corrosion. The inspection technology employed is ~90% naked-eye vision. We have developed and demonstrated robotic deployment of both remote enhanced 3D-stereoscopic video instrumentation for visual inspection and remote eddy current probes for instrumented inspection. This article describes the aircraft skin inspection application, how robotic deployment may alleviate human performance problems and workplace hazards during inspection, practical robotic deployment systems, their instrumentation packages, and our progress toward developing image enhancement and understanding techniques that could help aircraft inspectors to find cracks, corrosion, and other visually detectable damage.