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radial arm inclinometry - 970801
970801 imc
SCUBA2 observing crappy -
07:30 remove radial-arm inclinometer from the beam joining the
central bearing to the back right wheel (#3) and place it
on the beam going to the back left wheel (#2).
Also rotate it so that Y-axis points radially outwards,
X-axis points CW
This is to match the configuration of 951026 (and earlier ?)
gain low filter off
leg temps start middle end
09:10 inc970801cw 4.8 5.6 6.6
14:54 inc970801ccw 7.6 8.3 8.3
Analysis of c970801cw-ccw Each channel shows random noise + systematic structure. RX is the 'worst', RADY the best :
Ch 1 2 4 5 7 8
TX TY RADX RADY RX RY
rms scatter 0.9 1.1 1.6 0.6 3.0 1.7 "
As for previous CW-CCW comparisons, explanations for these
differences may be found in either thermal differences or
structural hysteresis ( see the report of
970717 ).
Step improvement The principal reason for changing the configuration was to enable a comparison with the pre-weld radial arm data of 951026. A comparison was made with the post-weld data from wheel 2 taken on 970712 (see the report of 970731 ) and qualitatively all of the joints could be seen to have been improved by the welding. But since the data were from different configurations, it was felt that a more secure conclusion could be drawn from data taken under circumstances as similar as possible. The 970801 data are included now in the plots available in the report of 970731 , and the conclusions of that report appear to need no correction. imc 970804 |