An alignment system for establishing and/or maintaining alignment of an automated robotic transfer mechanism in an automated detection system relative to a holding structure for holding one or more specimen containers, comprising: (a) an automated detection system configured to process specimen containers, said detection system having a housing enclosing an interior chamber; (b) a holding structure within said interior chamber, said holding structure having one or more holding wells configured to hold individual specimen containers, wherein said holding structure further comprises one or more fiducials; (c) an automated robotic transfer mechanism for the automated transfer of said specimen container within said interior chamber, said automated robotic transfer mechanism further comprising a gripping mechanism and a laser alignment device, said laser alignment device configured to detect said one or more fiducials and to thereby determine a home position of said automated transfer mechanism relative to said holding structure; and (d) a controller configured to determine the x and y positions of said one or more holding wells relative to said home position of said automated transfer mechanism relative to said holding structure; wherein said automated robotic transfer mechanism has at least one axis, a robotic head movable along said at least one axis, and a timing belt (62, 72); and a belt tensioning device (140, 200) configured to provide tension to said timing belt (62, 72); wherein the belt tensioning device comprises: a slide plate coupled to a tensioner housing and to an idler pulley; a fixed block and threaded shaft, wherein said threaded shaft is movable relative to said fixed block; said tensioner housing having a counter bore, a plunger and a compression mechanism configured to provide a force, wherein said plunger is movable relative to said counter bore and said compression mechanism; and wherein said threaded shaft is configured to drive said plunger into said counter bore, thereby compressing said compression mechanism and to provide tension to said timing belt; or wherein the belt tensioning device comprises: a stationary block having a threaded plunger, a compression mechanism and a plurality of teeth configured to engage a first end of said timing belt, wherein said stationary block is coupled to a carriage supporting the robotic transfer mechanism; and a slidable block having a counter bore and a plurality of teeth configured to engage a second end of said timing belt, wherein said threaded plunger is movable relative to said counter bore and said compression mechanism; and wherein said threaded plunger is configured to drive said threaded plunger into said counter bore, thereby compressing said compression mechanism and to provide tension to said timing belt. (a) an automated detection system configured to process specimen containers, said detection system having a housing enclosing an interior chamber; (b) a holding structure within said interior chamber, said holding structure having one or more holding wells configured to hold individual specimen containers, wherein said holding structure further comprises one or more fiducials; (c) an automated robotic transfer mechanism for the automated transfer of said specimen container within said interior chamber, said automated robotic transfer mechanism further comprising a gripping mechanism and a laser alignment device, said laser alignment device configured to detect said one or more fiducials and to thereby determine a home position of said automated transfer mechanism relative to said holding structure; and (d) a controller configured to determine the x and y positions of said one or more holding wells relative to said home position of said automated transfer mechanism relative to said holding structure; a slide plate coupled to a tensioner housing and to an idler pulley; a fixed block and threaded shaft, wherein said threaded shaft is movable relative to said fixed block; said tensioner housing having a counter bore, a plunger and a compression mechanism configured to provide a force, wherein said plunger is movable relative to said counter bore and said compression mechanism; and a stationary block having a threaded plunger, a compression mechanism and a plurality of teeth configured to engage a first end of said timing belt, wherein said stationary block is coupled to a carriage supporting the robotic transfer mechanism; and a slidable block having a counter bore and a plurality of teeth configured to engage a second end of said timing belt, wherein said threaded plunger is movable relative to said counter bore and said compression mechanism; and wherein said threaded plunger is configured to drive said threaded plunger into said counter bore, thereby compressing said compression mechanism and to provide tension to said timing belt.