Annals of Warsaw University of Life Sciences - SGGW.

18 G. Viselga, J.R. Kamińskichassis positioned according to the bendof the spar were by on average 1.6––2.1 times higher due to differences intramline unevenness.The distance between photodiodes,when A = 20–30 mm did not have anysignificant effect on the positioningprecision of the right chassis positionedby a trundle. Mean deviations rangedbetween 62–64 mm, and mean squaredeviations amounted to 19–26 mm, meandeviations of the other chassis rangedwithin wider limits of 29–63 mm, andmean square deviation when increasingthe distance between photodiodes from50 to 67 mm, increased by 1.3 times,from 81 to 104 mm.On the basis of the above-mentioneddata we can find that positioning speedis a decisive factor for positioningprecision. With increasing speed, inertiaforces increase when stopping or startingduring positioning, which increasespositioning deviations.Variation of asynchronous motorspower of electromechanical transmitteris rather typical (Fig. 5a). Duringpositioning, the power depended onthe speed of chassis. During automaticactuation of chassis motors the powerslightly exceeded the mean value. At0.083 m/s speed of chassis the powerinappreciably fluctuated and amountedto on average 0.08 kW. During the coursecorrections when motors temporarilyswitched off, the power declined to zero.Duration of corrections was about 0.8––1.0 s. The power of individual motorsof chassis slightly differed, most likelydue to the different distances coveredduring skid.Motor power of electromechanicaltransmitter of rope stretcher of implementcarriage at actuation moments wasat its peak, up to 4.8 kW, and duringstabilisation of implement tractionresistance, declined to 0.74 kW. Thelength of peak was 0.8–1.2 s. Due tothese power peaks, the working width ofthe implements was limited.An increase in positioning speedof PGM with an electromechanicaltransmitter to over 0.1 m/s wascomplicated due to the impacts duringtransitional processes.Comparison of power utilisationgraphs presented in Figure 5 suggeststhat chassis speeds in the case ofelectromechanical transmitter were4.7 times lower, and the power ofchassis differed by 3.7 times, i.e. withincreasing speed the power increasesless. Implement speeds in the case ofhydromechanical transmitter were by1.76 times higher, and the power 3times higher compared with implementcarriage pulling using electromechanicaltransmitter. This increase in poweroccurred due to the flow in throttletransmitter. When throttling is reduced,i.e. when revolution frequency is reducedby a mechanical transmitter, the powerdoes not increase significantly.Low power requirement of chassisenables to position chassis even bya muscle power of man. The power ofimplement carriage stretcher is higherand increases with increasing the workingwidth of implements. The total requiredpower can be fully generated bysolar energy photoconverters, havingmounted over the spar and chassis. Thearea of PGM cover fitted up from thephotoconverters l s × 2b would be 80–100m 2 for 20 m long spar and would protectPGM mechanism from precipitation. In