A chair is coupled to the shaft by chair coupling member ; a device carriage is coupled to the shaft by a carriage coupling member ; and {HEAD ~ a footrest assembly} is coupled to the shaft by {TAIL ~ a footrest coupling member}  
A chair is coupled to the shaft by chair coupling member ; a device carriage is coupled to the shaft by a carriage coupling member ; and { HEAD ~ a footrest assembly } is coupled to the shaft by { TAIL ~ a footrest coupling member }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH