A measurement system based on SICK laser scanner for measuring sewer chambers.
During the measurement of sewer chambers, it is normally necessary to actually enter the sewers. A step descent through the vertical shaft, moisture, dirt and unforeseeable circumstances make this activity an unpleasant and to some extent dangerous experience for the authorities and surveyors. For this reason, an unmanned, portable, opto-electronic solution for recording 3D data was sought.
The result is a chamber measurement system based on SICK’s LMS500. Mounted on the chamber measurement system’s turntable, the LMS500 is lowered upside down using a telescopic support. Once at the bottom, the LMS500 is rotated by 360° for the measurement. During the measurement, the measured data from the LMS500 as well as the actual position on the turntable are recorded. In practice the distances measured are between 1 m and 30 m. The result of a three-minute all-round scan using the LMS500 is a set of data comprising more than a million individual measured points. The vertical resolution is limited to 0.25°, the horizontal resolution is, on the other hand, variable. The 3D model of the sewer chamber is then generated using the chamber measurement system’s evaluation software.
By using the chamber measurement system and the LMS500 it is no longer necessary to enter chambers to make the measurements. Darkness, dark walls or moist concrete surfaces do not impair the function of the LMS500 in the 3D chamber measurement system. Due to the fine resolution of the measured data – even the smallest duct or the rungs on the ladder are clearly visible within the set of data – a very exact 3D image of the chambers can be generated.