The invention provides an arrangment that automatically sets {HEAD ~ the rollers} of the grid of rollers into {TAIL ~ self rotation} 
into
The invention provides an arrangment that automatically sets { HEAD ~ the rollers } of the grid of rollers into { TAIL ~ self rotation }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL