Hexagon CPT7, Инструкция по установке и эксплуатации

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Chapter 4 SPAN Operation
CPT7 and CPT7700 Installation and Operation User Manual v9 90
4.4.6 Multi-Line Body to Vehicle Frame Rotation Calibration Routine
The single pass Body to Vehicle frame offset calibration feature assumes flat ground when estimating the roll
offsets between the IMU Body and Vehicle frames, as this component of the rotational offset is difficult to
observe through typical ground vehicle motion. In practice this can result in an outstanding roll offset error as
high as several degrees. For applications where vehicle roll must be well known, or pass-to-pass accuracy of
a highly offset position is especially important, the Multi-Line IMU Body to Vehicle frame offset calibration
routine offers higher calibrated accuracy in roll. This is done by running independent calibrations over the
same ground path in opposite directions; averaging the results cancels out the effect of any terrain induced
roll. A minimum of two iterations are required. Additional iteration pairs can be executed for increased
reliability.
Figure 28: Multi-Line IMU Body to Vehicle Calibration
The steps for the calibration routine are:
1. Apply power to the CPT7.
2. Configure the SPAN system, see SPAN Configuration for CPT7 on page 78.
3. Ensure that an accurate lever arm has been entered into the system.
4. Perform an initial system alignment using one of the methods described in System Start-Up and
Alignment Techniques on page 83. Ensure the system reaches Solution Good.
5. Enable a new calibration using the INSCALIBRATE command, with the optional standard deviation target
omitted:
INSCALIBRATE RBV NEW