Application of hand-held laser rangefinder in house measurement
Housing measurement has always been a concern and painstaking work of the housing management department. The area map of housing survey is a drawing directly used as the title certificate and has legal effect. It is not only directly facing the people, but also directly related to the economic interests of the people, so it is particularly important to control the measurement error of the house. According to the past habits, measuring the building area and usable area with a tape measure or a steel tape measure can meet the basic requirements, but there are big errors in long-distance measurement, height measurement, and difficult-to-reach measurement, and there are shortcomings such as heavy labor intensity and complicated work. Today, with the rapid development of high technology, such primitive and traditional measurement methods have been adopted. Therefore, after the introduction of two Leica hand-held laser rangefinders, after several months of practical use, it is generally considered that the instruments are especially suitable for the measurement of buildings with complex building structures, middle and high-rise buildings and long distances. Easy to use, accurate measurement data (3 mm accuracy), improved work efficiency (non-contact measurement), completely abandoned the method of measuring houses with a tape measure (or steel tape measure), reduced the survey error, ensured the accuracy of area measurement, and the measurement results made the owners more convinced. Of course, the instrument also has some aspects that need to be improved urgently. For example, under the strong sunlight, it is difficult to see the long-distance target object clearly, and it needs the help of telescopes and other accessories. In addition, it is laborious to calibrate the level bubble every time, so it is best to calibrate it automatically. In a word, the instrument is still popular with us.
Laser rangefinder generally uses two ways to measure distance: pulse method and phase method. The process of pulse ranging is as follows: the laser emitted by the rangefinder is reflected by the measured object and then received by the rangefinder, and the rangefinder also records the round-trip time of the laser. Half of the product of the speed of light and the round trip time is the distance between the rangefinder and the measured object.
