Results of experiment shows, that concentration of the hydrogen dissolved in the stainless steel type 304 after keeping in normal atmosphere is CH2 = 2*1019 at/sm3, instead of theoretically expected CH2 = 2*1019 at/sm3, similarly, for deuterium, dissolved at CD2 = 7*10-6Pa, its concentration, instead of theoretically expected C theorD2 = 8*1015 at/sm3 is CD2 = 1*1018 at/sm3. As for hydrogen also as for deuterium it is possible to explain their increased concentration by the relay dissociation of sorbed water The results show that the residual atmosphere of hydrogen or deuterium influences on ions exchange processes of deuterium and hydrogen in layers of sorbed water. So, in the submitted results it is enough 0,002% dissociation of sorbed water to ensure the pointed mentioned concentration. Experiment with the sample keeping (during 76 days) in the atmosphere of deuterium at pressure PD2 = 5*10-4Pa shows, that the maximal concentration of the dissolved deuterium is CD2 = 1*1018 at/sm3, that is about eight times less than expected theoretically. Concentration of the dissolved gases grows up to C maxH2 = 2*1021 at/sm3 and C maxD2 = 3*1019 at/sm3 as a result of mechanical action influence that corresponds to the 8,5% dissociation of H2O, and corresponds to 0,1% dissociation of HDO. So it was shown that the friction processes stimulates the process of sorbed water dissociation.
The control system of adaptive optic of a large astronomical segmentated telescope was designed and tested. The dynamic model and the amplitude-frequency analysis of the new magnetic rheology (MR) drive are presented. The loop controlled drive consists of hydrostatic carrier, MR hydraulic loop controlling system, elastic thin wall seal, stainless seal which are united in a single three coordinate manipulator. This combination ensures short positioning error δφ⪅50 nm and small time of response. The main feature of a large astronomical telescope (diameter 25 m) is the large number (in our case 512) of primary mirror segments usage, which are united in one reflecting system. This design makes easier the problem of the primary mirror manufacturing but brings another problem to ensure precise movement of every mirror segment movement and to provides a perfect coincidence of the mirror segments constantly. Suggested parameters of the drive, based on magnetic rheology (MR) liquid are: precision δφ⪅50 nm, time of response T≤0.2 s. Error of positioning of loop-controlled MR drive may be expressed: δφ = δr + δdb + δf + δi, where δr -- 'reproduction' error (depends on drive structure and controlling system, and in our case the drive ensures δr = 0); δdb -- 'disturbance' error (δdb = 5...10 nm); δf -- error, because of static friction forces action (δf equals kt x Fst = 2 x Is/ki = 30 nm, where kt -- transformation coefficient of the drive; Fst -- static force in the drive; Is -- 'starting' current in the drive; ki -- transformation coefficient of the measuring system); δi -- 'instrumental' error. In case of a laser interferometer usage δi = 10 nm and the summarized error is δφ≤50 nm. Time of response T of the drive depends mainly on the combination of time constants of the next elements: MR-valve Tm, elastic elements (pipes, thin-wall tubes, bellows) Tel, moved object (mirror segments) Ts. Experiments show what the MR drive ensures: Tm = 20 ms, Tcl = 20 ms, Ts = 100 ms. Analysis of the amplitude-frequency graphs shows, that the MR-drive ensures summarized time of response till T≤110 ms.
the development of the large-scale telescope building is pressingly putting the question of the 5-Th generation supertelescope development with 25 m diameter primary mirror, having penetrating ability about 29 magnitude. The volume of information obtained on the supertelescope, will allow to expand the idea about the Universe origin and evolution greatly.
KEYWORDS: Magnetism, Mirrors, Liquids, Control systems, Control systems design, Signal processing, Astronomical telescopes, Laminated object manufacturing, Manufacturing, Optical design
The design, parameters and the amplitude-frequency analysis of the new magnetic rheology (MR) drive are presented. The combination of hydrostatic carrier, MR hydraulic loop control, elastic thin wall seal joined in a single unit ensures small positioning error nm and small time of response T <EQ 200 ms.
KEYWORDS: Magnetism, Scanning tunneling microscopy, Control systems, Liquids, Actuators, Interferometers, Thulium, Error analysis, Control systems design, Photonics systems
The manipulators of scanning tunneling microscope (STM) usually use 'long-travel' mechanically drived X-Y stages with piezoceramic actuators together with piezoceramic tubes. Magnetic- and electric Rheology manipulators combine the functions of the both drives in single unit and ensure the precision and the length of the travel L <EQ 200 mm along X, Y axes and L <EQ 400 mic along Z axe. Error of positioning of loop-contorlled MR- and ER drive may be expressed.
KEYWORDS: Mirrors, Magnetism, Telescopes, Control systems, Actuators, Liquids, Control systems design, Reflector telescopes, Manufacturing, Analytical research
The main feature of large ten-meter telescope is usage of 84 primary mirror segments which are united in one reflecting system. This decision makes easier the problem of the primary mirror manufacturing but brings another task -- drives designing for every mirror segment moving with high precision (nanometer accuracy) which provides perfect coincidence of mirror segments constantly. There are suggested two variants of the drive construction based on magnetic-rheology liquid. This drive provides nanometer precision and millisecond quickaction.
The main feature of a large ten-meters telescope is application of 84 segment primary mirrors which are united in one reflecting system. This decision makes the problem of the primary mirror designing easier yet brings another task: the designing of every mirror segment high precision (nanometer accuracy) drive, which provides perfect coincidence of segment mirrors constantly. There are suggested two variants of the drive construction based on magnetic rheology liquid. This drive provides nanometer precision and millisecond quick action.
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