Certain dynamic stability characteristics of an alternate method of mounting a front-end loader to a farm tractor were compared to those of a conventionally mounted front-end loader operating on a specified terrain. One objective of the study was to determine if the alternate method of mounting a front-end loader resulted in better stability characteristics and, in turn, safer operation than a conventional front-end loader. Another objective was to determine if a three-dimensional sonic digitizer could monitor the motion of the scale model tractor-loader systems accurately enough to perform a comparison between the systems. This article describes the second objective of the study. A battery-powered, 1/4 scale model tractor-loader was used to perform experimental tests. Both tractor-loader systems were operated on two slopes and on random combinations of two sinusoidal bump heights, two load weights, two loader heights, and two velocities. Three replications were performed of each test condition. A three-dimensional sonic digitizer was utilized to monitor the motion of the scale model tractor-loader systems. The sonic digitizing system made it possible to record position of the tractor-loader systems versus time at levels of frequency and accuracy faster than any previous methods of obtaining this type of data. This greater number of observations allowed systems to be statistically compared, which was not possible with previous data collection systems. The digitizing system was able to locate each sound emitter accurately. Elapsed time between emitter firing sequences may have resulted in the measured roll and front axle rotation angles to be less than actual peaks.

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Published in Transactions of the ASAE, v. 39, issue 2, p. 435-441.

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This research was funded in part by a grant from the USDA-Agricultural Research Service.

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The investigation reported in this article (No. UK 94-2-117) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director.