摘要 |
The invention relates to a system for directing an apparatus, such as a crane bridge (1), moving on wheels along rails, which apparatus comprises a specified drive arrangement (m1, m2, m3, m4; k1, k2) on both sides of a roadway defined by rails (3), and which system comprises in the apparatus at least on one side of the roadway at least two successive detectors (d1, d2) in the direction of the rail (3) for measuring a lateral distance (l1, l2) of a specific part of an edge (e1, e2) of the apparatus to be driven from the rail, a control loop (CS) guiding the drive arrangements, a controller of the loop being able to direct the distance measurements (l1, l2) of the detectors (d1, d2) to desired values so that the apparatus to be driven will move straight, and an outer control loop (CU) whose controller is able to direct the reference value of the controller of the inner control loop in such a manner that the average of the distance measurements (l1, l2) provided by the detectors (d1, d2) reaches the desired reference value so that the wheels (2) of the apparatus to be driven will move in the middle of the rails (3).
|