into the ISS pressurized module. Th e stand alone test also all ows pa rallel a ctivities to occu r on the ISS   module witho ut being con strained by the  CBM and lim iting acce ss to the module hatch way. 

On the Active  CBM half, all mecha nisms are exerci sed throug h thei r full motions,  representing the on-o rbit  pre-berthing f light ope rations. Powered  bolts a re extended and retracte d, cap ture latche s open ed a nd  closed and ready to lat ch assem blies depresse d and relea sed. Powe r, com mand i nitialization an d data  feedba ck are perfo rmed and mo nitored  throu gh a separate  supp ort equi pment control rack. Primary and  redundant po wer string s are used with comm unications verifie d using both p rimary and re dunda nt 1553   bus path s. Each Controlle r Panel Asse mbly is assi gned as the M aster controller throu gh th e powe r and  data chan ges.  A berthing  simulato r, rep resenting a Passive CBM half (with inte rface  seal) i s mated to the  Active CBM (Figure 5). T he simul ator is manually p ositione d to all ow powere d bolt eng agem ent. Powe red  bolts are act uated u sing flight comm and step s and allowin g load feedba ck to the sup port equipment  control rack. Final l oad is approximat ely 25% of fl ight level p re-load, suffici ent eno ugh to  allow seal  comp ression  and  full con tact at the  interface. With the simulato r mate d, me asurements are ta ken to  ensure suffici ent clea rances between th e coa rse an d fine alignin g feature s of the CBM. Inspectio ns are  perfo rmed to  assure cl earances of the  simulato r Passive CBM comp onents within the vo lume of the   Active CBM half and surroundi ng mo dule bul khead feature s. A seal l eak check is performed to en sure  integrity of the Active CB M seal surfa ce. De-berth ing comm ands are pe rform ed to rele ase the simulato r  for the Ac tive CBM half.  At this  point, the Ac tive CBM is  connec ted to the pressuriz ed module and  become s an integral u nit of that module.  

Integrated  Active CBM and   Pressu rized  modul e testing i s  perfo rmed  using flight p ower and  flight softwa re for a ctuation and   comm and of the Active CBM. Again,   each me chanism  is exercise d  throug h a  set of motions fo r  verification of control and data  feedba ck. Each  Controll er Pa nel  Asse mbly i s assign ed a s Maste r for  comm and and control  function s.  Conclusion of this testin g verifies th e  Active CBM ready for flight. 

On the Pa ssive CBM half  an Active   CBM simul ator is utilized.  This is a  more  simplified te st du e to no  powere d mech anisms on the  Passive half. The simulator is  manually po sitione d, attache d and  loade d to a spe cified g ap at the   interface seal between  the sim ulator an d Pa ssive CBM ha lf. T his gap represents the min imal  comp ression on the interfa ce seal for assuri ng le ak testing of the seal. The same mea sureme nts bet ween  aligning  featu res are p erformed and assuran ce of clearances wit hin the Pa ssive CBM volu me mad e. A  seal lea k check is perfo rmed to assure integrity of  both the Passi ve CBM seal  surfa ce and the installed   interface seal . The Active CBM Simulat or is removed and the Pa ssive CBM i s ready for flight . This set of  testing i s performed late in the Pressu rized Mod ule flow in preparation for flight  due to the  interface  seal  being expo sed at completi on of test an d the locatio n of the Passi ve CBM is g enerally the last hatchway  acce ssed an d clo sed for module p rocessing.  Figure 5.  CBM Be rthing  Simulator 

The com pletion of stan dalone and  integrated  testin g of the  CBM on th e Pressuri zed Module assu res  correct operation of the CBM and interchangeability of the CBM,  to allow any Passive to berth and deberth to any  Active, is maintained. This s et of verification  and te sting has resulted  in the current  successful twelve berthin g and six de -berthing on orbit operatio ns of  ISS pressuri zed mo dules. 

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