Tilt sensors

The basic layout of a laser guided AO system is shown in Fig. 1. Implementation of LGS referencing requires the addition of a laser and launch telescope, plus one or more additional wavefront sensors (WFS), including a tip-tilt sensor. Multiple LGSs require additional lasers and launch systems, or a multiplexing scheme. Multi-conjugate AO (MCAO) requires additional deformable mirrors, operating in series, plus multiple WFSs. 

LGS/AO System Integration. A number of modifications have been implemented in the Keck II AO system to accommodate LGS/AO (Contos et al., 2002) a tip-tilt sensor to provide NGS- based tip-tilt, a low bandwidth WFS (LBWFS) to measure long term focus using a NGS, focus tracking for the high bandwidth WFS (HBWFS) looking at the LGS, and a tip-tilt control loop for the laser pointing. 

To overcome the effects associated with laser uplink, a quadrupole tip-tilt sensor on the AO bench is interfaced with the tip-tilt mirror on laser table... 

Position, movements Tilt sensors, acceleration sensors... 

We expect these micromachined sensors to become more and more important in the household industry, in many domestic applications of silicon pressure sensors, acceleration sensors, tilt sensors, infrared detectors and thermopiles, flow meters, as well as gas sensors and liquid constituent sensors. 

Dai, R Stein, R.B. et al.. Application of tilt sensors in functional electrical stimulation, IEEE Trans. Rehab. Eng. TRE-4 63-72,1996. 

Wearable exo-skeleton Tilt sensor at torso Re Walk [80]... 

Recent tests by other workers Gust et al, 1994) seem to indicate that the flow around and inside sediment traps may have considerable effects on the trap collection efficiency at shallow depths, whereas the deep-ocean traps appear to collect the actual flux. We recommend, therefore, to equip the instruments with current meters, and depth and tilt sensors. This allows a description of the dynamics of the hydrographical field and its effects on mooring line motions as well as on the excursions of traps from the vertical position, and may even offer the basis for corrections of hydrodynamic biases in particle flux measurements. 

Tilt Sensor repeatability was studied for 38° tilt angles in both the clockwise and counter-clockwise directions. The maximum measurement error in this case was less than 2.0°, with a mean error of 0.73°. The mean measurement system result after ten trials was 37.27°, with a standard deviation of 0.63°. This implies that 90% of measured tilt for an actual tilt of 38° is in the range of 37.27+3x0.63 and 37.27-3x0.63 which is from 35.38 to 39.16°. 

Wadhams, P. and S. Wells, Ice surface oscillation measurements on SIMI using strain, heave and tilt sensors, Proc. of the Sea Ice Mechanics and Arctic Modeling Workshop, North West Research Assoc., Inc., Bellevue, WA, vol. 2, 176-189, 1995. 

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