A platform is positioned above the conveyor and is capable of alternatingly moving in either one of a first direction, substantially similar to the direction of motion of the conveyor, and a second direction, substantially opposite to the direction of {HEAD ~ motion} of {TAIL ~ the conveyor} 
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A platform is positioned above the conveyor and is capable of alternatingly moving in either one of a first direction , substantially similar to the direction of motion of the conveyor , and a second direction , substantially opposite to the direction of { HEAD ~ motion } of { TAIL ~ the conveyor }
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