Comprehensive and Highly Accurate Measurements of Crane Runways, Profiles and Fastenings

Abstract

The process of surveying crane runways has been continually refined due to the competitive situation, modern surveying instruments, additional sensors, accessories and evaluation procedures. Guidelines, such as the International Organization for Standardization (ISO) 12488-1, define target values that must be determined by survey. For a crane runway these are for example the span, the position and height of the rails. The process has to be objective and reproducible. However, common processes of surveying crane runways do not meet these requirements sufficiently. The evaluation of the protocols, ideally by an expert, requires many years of experience. Additionally, the recording of crucial parameters, e.g., the wear of the rail, or the condition of the rail fastening and rail joints, is not regulated and for that reason are often not considered during the measurement. To solve this deficit the Advanced Rail Track Inspection System (ARTIS) was developed. ARTIS is used to measure the 3D position of crane rails, the cross-section of the crane rails, joints and, for the first time, the (crane-rail) fastenings. The system consists of a monitoring vehicle and an external tracking sensor. It makes kinematic observations with the tracking sensor from outside the rail run, e.g., the floor of an overhead crane runway, possible. In this paper we present stages of the development process of ARTIS, new target values, calibration of sensors and results of a test measurement.

Self‐segmenting of rennet‐induced milk gel in cheesemaking tank

“…You can estimate the height of the displacement of the milk curds relative to each other, the width and depth of the boundaries between the segments by following the light section method widely used in the technique of measuring the roughness of various surfaces (Dennig et al . ). To do this, an image of regular linear stripes of a certain width (raster) was projected onto the surface of the milk gel in a cheesemaking tank using an LCD‐projector.…”

Simultaneous Hand–Eye and Intrinsic Calibration of a Laser Profilometer Mounted on a Robot Arm

“…However, we must emphasize that fixation of certain parameters also depends on the specific configuration of a laser profilometer, for example, the magnitude of optical distortions, which affects the degree of the measuring system nonlinearity. The Gauss–Helmert model with constraints [ 24 , 34 ] is one of the possible improvements of the optimization algorithm.…”

“…However, the 3D sensor was not attached to the robot arm or other type of actuator; thus, hand–eye parameters were not calculated. On the other hand, the rail track inspection system [ 24 ] based on laser profilometry and a 2D laser scanner attached to the portable mobile platform for mapping the outdoor environment [ 25 ] was calibrated using Gauss–Helmert model. The reference geometry composed of multiple nonparallel planes was measured in the first step, and numerical optimization of only extrinsic transformation parameters was executed in the second step.…”

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