Armstrong creates sculptures, paintings, drawings (from miniature to wall size), artist's books, multimedia artworks involving computers sound and light, and constructs permanent installations in atrium spaces.
She was an educator for several years at the University of Alabama at Birmingham, later she moved to New York City in 1981.
Her first exhibition in New York City was at PS1 in 1982, "'the Sound Corridor'" curated by William Hellermen.
This installation began her multimedia series of work entitled "'Airplayer'" which ended in 1992 at the CB's 313 Gallery and Bar (next door to CBGB) on the Bowery with "'Airplayer XIV'" – both installations utilized mechanisms for movement and sound.
[7] Armstrong's work is included in collections nationally and internationally among them Victoria and Albert Museum in London, UK, MoMA[12][13] in New York City, WAAND "Women Artists Archives National Directory, Ira Silverberg Papers, Sun and Moon Press Archive, Sackner Archive of Visual and Concrete Poetry.