How to check the three-axis relationship of rangefinder
In the process of using the rangefinder, the relationship between the three axes (telescope aiming axis, rangefinder transmitting axis and receiving axis) often changes due to vibration and collision during long-term work and transportation. Conventional calibration methods are simple to operate, but the calibration results are not accurate enough.
1. Calibration principle
By measuring the angular values of the range of the return light signal of the rangefinder in the horizontal direction and the vertical direction, the correct readings of the dial at four critical positions (weak return light signal) when the three-week relationship of the rangefinder meets the requirements are calculated. After rotating the inching screw to the correct reading position of the dial, correct the return light signal of the rangefinder to a critical state, so that the corrected sighting mirror mark is in the center of the return light signal range. Take the verification of three-axis relationship of DI2002 rangefinder as an example.
2. Test of parallelism in horizontal direction
(1) Place a reflector about 200m away from the range finder, aim the reflector mark with a telescope, and read the reading a (145 04' 30'') of the horizontal dial.
(2) Slowly rotate the horizontal inching screw of the theodolite to make the aiming direction deviate from the mirror mark to the left, and observe the change of the return light signal of the range finder until the return light signal is in a critical state (the return light signal keeps jumping between one grid and no signal), and read the levelness reading a (144 57' 59'').
(3) Use the same method to measure the horizontal dial reading a (145 07' 37'') when it deviates from the critical state on the right side of the mirror mark.
(4) Calculate the horizontal deviation angle according to the following formula:
3. Horizontal parallelism correction
(1) Calculate the correct angle value when it deviates from the critical state on the left and right of the mirror mark according to the following formula.
