An angle α is then obtained between the dust bag and wall and the space thereof is filled with pressure sensors that create {HEAD ~ signals} used in indicating {TAIL ~ relative fullness} as previously described 
used in indicating
An angle α is then obtained between the dust bag and wall and the space thereof is filled with pressure sensors that create { HEAD ~ signals } used in indicating { TAIL ~ relative fullness } as previously described
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 REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH