A non-conservative (angular momentum is not conserved) procedure is developed to safely retrieve a tethered passive astronaut on an extravehicular assignment (EVA). The safe retrieval of a tethered astronaut by conservative procedures has been shown to be impossible unless the conditions upon initiation of retrieval are exceptional. Safe recovery is defined as a max rotation rate of 0.5 rad/sec, a max impact velocity of 5.0 ft/sec, and a max centripetal acceleration of 8.0 ft/sec squared. This last requirement is treated by limiting the tether tension to 100.0 lfb as the astronaut's mass is taken as 13.04 slugs. To ensure the max impact velocity is not exceeded, the astronaut is reeled in at a constant rate of 5.0 ft/sec. A safe recovery is achieved by insisting that the space vehicle 'track' the astronaut during the EVA. Then, when retrieval is initiated, a force is applied through the center of mass of the space vehicle to null the angular acceleration of the astronaut with respect to the space vehicle.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    A Non-Conservative Retrieval of a Tethered Passive Astronaut


    Contributors:

    Publication date :

    1975


    Size :

    71 pages


    Type of media :

    Report


    Type of material :

    No indication


    Language :

    English




    Retrieving tethered astronaut

    Beasley, G.P. / Brissenden, R.F. / Straly, W.H. et al. | Engineering Index Backfile | 1965


    Three-mass retrieval study for gemini tethered astronaut

    Poli, C.R. / Hanavan, Jr., E.P. | Engineering Index Backfile | 1966



    Retrieving the tethered astronaut.

    Adlhoch, R. W. / Beasley, G. P. / Brissenden, R. F. et al. | NTRS | 1965


    Reversed-Thrust Laser Propulsion and Astronaut Retrieval

    Sinko, John E. / Schlecht, Clifford A. | AIAA | 2011