Changes between Version 56 and Version 57 of Processing/LeverArmOffset

Timestamp:

Dec 14, 2022, 3:47:26 PM (2 years ago)

Author:

wja

Comment:

--

Processing/LeverArmOffset

@@ -12 +12 @@
 
 ----
+
+= 2022 =
+
+This year had two flight configurations:
+
+1) Owl attached to IPAS20 IMU, PhaseOne
+2) Optech LiDAR, IBIS, PhaseOne
+
+Units are the following:
+
+ * X: Positive towards starboard (right)
+ * Y: Positive towards the nose
+ * Z: Positive towards the sky
+
+'''Owl'''
+
+These measurements have been derived from the following:
+
+ * Aircraft survey (note this is not the usual twin otter!): `/users/rsg/arsf/arsf_data/2022/misc/aircraft_survey_VP-FBL/twin_otter.dwg`. Viewed with LibreCAD.
+
+ * Owl schematics: `/users/rsg/arsf/doc/schematics/owl/`
+
+'''X'''
+
+Back left corner offset from antennae was measured from survey. Offset to Owl pupil measured from schematic.
+
+-0.3970 - 0.1415 = '''-0.5385'''
+
+'''Y'''
+
+The same back left corner offset used from survey. Offset to pupil from schematic.
+
+0.799 - 0.09565 = '''0.70335'''
+
+'''Z'''
+
+Base of sensor offset from anntennae was measured from survey. Offset from this to the pupil was measured from the schematic.
+
+-1.541 + 0.1613 = '''-1.3797'''
+
+'''IPAS20 IMU'''
+
+This IMU is only to be used for processing Owl data. It was attached to the Owl, which was on a fixure allowing the viewing angle to me moved.
+
+Unfortunatly, we do not have information regarding the inside reference location of this IMU. The survey has been used to find the coordinates of the center of the top face of the instrument, and then half the length was offset for the Z offset. As per done previously, see `/users/rsg/arsf/arsf_data/2012/misc/dornier_survey/workings_out.txt`.
+
+These values are for the lengths from the antennae to the IMU, but for input into IPAS TC, these are reversed so that they are the distance from the IMU to the antennae.
+
+'''X'''
+
+-0.2415 - (0.093 / 2) = '''-0.288'''
+
+'''Y'''
+
+0.5915 + (0.093 / 2) = '''0.638'''
+
+'''Z'''
+
+-1.368 - ((-1.368 - -1.468) / 2) = '''-1.418'''
+
+'''IBIS'''
+
+Callum Middleton measured from the antennae to the back right corner of the IBIS. See image `ibis_ref_point.jpg` for the location of this corner.
+
+Using the schematic, the offset to the IBIS pupil has been calculated.
+
+'''X'''
+
+The 161 value on the schematic has been rounded down to 160 (0.16 below) to account for the 'cutaway' edge where the reference point was measured. We don't have the exact measurement for this axis otherwise.
+
+-0.583 - (0.160 / 2) = '''-1.383'''
+
+'''Y'''
+
+-0.814 - (0.230 - 0.075) = '''-0.969'''
+
+'''Z'''
+
+(-1.014 - (0.498 + 0.09)) + 0.062 = '''-1.54'''
+
 = 2015 =