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Advances in astronomy led to the demand for measuring the spectra of multiple night sky objects simultaneously. Some of these Multi-Object Spectrographs use robotic systems that position optical fibers in the focal plane of the observing telescope. These systems rely on precise fiber placement in order to collect the light spectra of faint stars and galaxies. Here, we present how to design, control, and operate micro SCARA-like robots to position optical fibers to micrometer precision. As an illustrative example, we show the design and performance results of the SDSS-V fiber positioner, which has been build for the Apache Point Observatory and the Las Campanas Observatory with 500 units for each telescope.

Every year, several ten thousand patients die on mechanical ventilation. This happens because the lungs can currently not be monitored adequately in real-time, and thus sub optimal ventilator settings can cause severe lung tissue damage. Electrical Impedance Tomography (EIT) produces a real-time image sequence of the breathing lungs. So far, no automatic method has been available to detect the physiological regional lung states. We propose an algorithm that clusters the raw pixel based data of the EIT image sequence into clinically relevant regions with similar physiological behavior. Our implementation is very robust regarding bad signal quality due to low signal to noise ratio (SNR). It is also highly efficient in terms of computational complexity by considering additional physiological knowledge. The functionality of the algorithm has been verified using EIT data of a human subject with acute lung failure at various Positive End-Expiratory Pressure (PEEP) levels. The results are in agreement with the study protocol. This method brings EIT treatment one step closer towards protective ventilation therapy.

In the large-scale, Dark Energy Spectroscopic Instrument (DESI), thousands of fiber positioners will be used. Those are robotic positioners, with two axis, and having the size of a pen. They are tightly packed on the focal plane of the telescope. Dedicated micro-robots have been developed and they use 4mm brushless DC motors. To simplify the implementation and reduce the space occupancy, each actuator will integrate its own electronic control board. This board will be used to communicate with the central trajectory generator, manage low level control tasks and motor current feeding. In this context, we present a solution for a highly compact electronic. This electronic is composed of two layers. The first is the power stage that can drive simultaneously two brushless motors. The second one consists of a fast microcontroller and deals with different control tasks: communication, acquisition of the hall sensor signals, commutation of the motors phases, and performing position and current regulation. A set of diagnostic functions are also implemented to detect failure in the motors or the sensors, and to sense abnormal load change that may be the result of two robots colliding., Comment: 7 pages, 10 figures, SPIE Digital Library