Annals of Warsaw University of Life Sciences - SGGW.

16 G. Viselga, J.R. KamińskiNumber of positions to corrections80706050403020100both tramlines of chassis not levelledone tramline levelled1 2 3 4Succession of correctionsFIGURE 2. The effects of tramline on the frequency of course correctionWhen moving along natural nonlevelledtramlines both tracks needlevelling, because levelling of onetramline even increases the number ofpositions to corrections and increases theinter-difference of the distance done bythe chassis in the direction of the courseduring correction. This results from thefact that when both chassis move alongnon-levelled tramlines their unevennesscompensate one another.When positioning trundle andphotodiodes of laser catcher with A = 30mm inter-axial distance were mountedon the same chassis (C = 0), mean coursedeviation of this chassis amounted to67.6 mm, and mean square deviation±15.0 mm (Fig. 3). Straight-line coursedeviations of the other chassis weredetermined by the unevenness of itstramline and other already-mentionedfactors, therefore its mean straight-linecourse deviation was higher (102.2mm), and mean square deviation wasconsiderably higher ±33.9 mm.When photodiodes are mounted in themiddle of the spar (C = 6 m) and the leftchassis is positioned by the trundle, meandeviation from the straight-line course ofthe right chassis significantly declines,compared with the first case (75.6 mm)(Fig. 4). Its average straight-line coursedeviation are smaller (25.5 mm). Meansquare deviations of straight-line coursedeviations were 4.1 mm bigger for theright chassis.Precision of positioning depends onthe speed of PGM. When increasing thespeed from 0.08 m/s to 0.24 m/s, thedistance between the left, positioned bya trundle, chassis stops in the positionsincreased by on average 31 mm, and thatof the right chassis by 20 mm. When thespeed is increased from 0.08 m/s to 0.39m/s, this distance increases by 61 mm and55 mm, respectively. Average positioningsquare deviation of the chassis positionedby a trundle is lower and at a speed of0.08 m/s it reached on average ±32 mm.An increase in the chassis speed resultsin an increases in mean square deviation.At a speed of 0.38 m/s it was ±50 mm.Average square deviations of thedistance between positions of the right