Procedure "red pants"
The "Rote Hose" procedure is a procedure for eliminating a possible measurement deviation - the slope of the horizon - with the level .
Reasons for the measurement error
Due to their principle, compensators also never work completely error-free, they tend to over- or under-compensation.
If the level with a slight inclination of the vertical axis positioned, he is taken this through the compensator balanced, but the perpendicular line of sight is no longer in a horizontal but in an inclined plane ( vertical offset ). As a result of joint friction and similar influences, the compensator does not reach its ideal position, but remains at an incline that deviates slightly from the horizontal ( compensator residual deviation ).
Height offset and residual compensator deviation work together and lead to what is known as the slope of the horizon , which, however, is not worth mentioning if the circular level is carefully installed . Under the following conditions, the errors between a pair of viewpoints average out almost completely:
- same target ranges
- Staff - instrument - staff form a straight line
Procedure "red pants"
To make the measurement even more precise, the instrument is leveled as follows:
- Bring in the circular level from the first position to foresight
- Bring in the circular level at the next position to look back
- Bring in the circular level at the nearest position to foresight
- etc.
When working with two measuring assistants, the level is always placed on the same staff - and therefore always on the same staff carrier. To make it easier to remember, it was jokingly suggested that he should wear red trousers. Thus the process was given the name "Rote Hose".
literature
- Heribert Kahmen: Surveyors . 20th edition.
- Eberhard Baumann: surveying . 5th edition. Dummies.