This　paper　is　concerned　with　tracking　control　of　a　dynamic　model　consisting　of　a　flexible　beam　rotated　by　a　motor　in　a　horizontal　plane　at　the　one　end　and　a　tip　body　rigidly　attached　at　the　free　end.　The　well-posedness　of　the　closed　loop　systems　considering　the　dissipative　nonlinear　boundary　feedback　is　discussed　and　the　asymptotic　stability　about　difference　energy　of　the　hybrid　system　is　also　investigated.　©　1995,　by　North　Atlantic　Science　Publishing　Company.