Angular calibration of radar antenna system is composed of the calibration of angular error sensitivities (also called directional sensitivity), adjustment of cross-coupling of azimuth and elevation signals, and the calibrations of system errors such as antenna axial system error, dynamic delay and so on.
Machine tools and coordinate measurement machine (CMM) with rectangular coordinate system have 21 items of geometric errors, 18 of which are measured by ready-made interferometer, the rest 3 items rolling angle errors are the most difficult parameter to be measured.
The relative spiral angle and pressure angle errors were defined and introduced into the evaluation of the teeth mating precision,which had been carried out by the measurements of teeth form and pitch errors.
Simulation results show that, under the condition of big initial errors, after 360 seconds' alignment on moving base, the attitude angle errors of IMU can be decreased to no more than 10 angles second, and the position and velocity errors had been corrected effectively. So the alignment algorithm on moving base is proved to be effective.
The thesis discussed three methods of i angle error (angle between colhmating and level axis inspection. Compared the practical measurements of the methods ,merits ,and defects and accuracy of the methods are obtained. It's useful for i angle error inspection.
In addition, the interception accuracy increased when the target travel time was above the MPT, and the angular error was smaller in RM than in AM.
After local load to the knee muscles, a significant increase of absolute angular error was observed (2.56°).
The angular error of the system is small (1.3°), the reproducibility is high (0.2°), and the inherent angular noise is small (0.04°) and independent of the orientation of the device.
Extensive experiments on real and simulated motions proved the reliability (maximum angular error less than 1o, maximum point reconstruction less than 1mm) of the developed system, which is robust to false matching caused by marker occlusions.
If the extrapolative transducer is well designed, the amplitude error can be reduced to 2-3% and the angular error to 30-40'.
A decreased angular divergence or increased ultimate ion-beam current density is achieved by a change in the potential drop in the space charge sheath between the plasma and the ion optics.
It is demonstrated that ultrathin beams with an effective cross sectionh?100 nm and an angular divergence Δ??2' below the diffraction limit can be obtained.
The beam intensity, angular divergence, and spot size on the target should be at least 5 × 106protons per cycle, below 2.5 mrad, and no larger than 10 (horizontal) and 14 (vertical) mm, respectively.
It is shown that the beam width increases as the square root of the path length in an anisotropic medium, whereas the angular divergence varies in inverse proportion to the square root of the path length.
With account of the absence of deformation in the lowest mode due to selection, this implies that resonators containing dichroic media (including photon crystals) are promising for reducing the angular divergence of laser beams.