Cargo management unit A cargo management unit , or CMU , was a small utility craft in use by the Federation from the mid - 23rd century to the 24th century . Service history . CMUs existed during the mid 23rd century , often assigned to Starfleet shipyard s in orbit of Earth . They assisted in the refitting of the original at the San Francisco Fleet Yards as well as the launch of the . ( ; ) CMUs continued to be used into the 24th century and were numerous at Utopia Planitia Fleet Yards and Deep Space 9 . ( ) The CMUs at DS9 were generally gray in color . ( season 4 credits ) In 2364 , the acquired a CMU from Support Services on Relva VII in order to eliminate three older and bulkier units from the cargo bay s . ( ) By 2379 , new silver craft resembling CMUs were in use at the spacedock where the " Enterprise " - E was repaired following the Battle of the Bassen Rift . ( ) Technical data . The CMU was a single - occupant vehicle with seating for the pilot only . Generally , the pilot needed to be spacesuit ed , especially if the pilot was planning to perform a space walk . The front of the CMU featured several large windows . The craft also had a large headlight at its extreme forward end for illuminating a work area . As the CMU was primarily a maintenance craft , it could be equipped with a variety of tools , including a set of dual remote manipulator arms called the Grabber Sled . The CMU could also serve as a tug for cargo modules with the Cargo - Train Attachment . The CMU could operate both in the vacuum of space and within the atmospheric and gravitational conditions of a starship cargo bay or planet ary surface . ( ) Appendices . Background information . The Cargo Management Unit was never identified by name in dialogue ; the name was only seen , on a display in the episode " Coming of Age " . During the absence of a name , the moniker " Work Bee " was adopted by many publications , official and unofficial , including the reference work " " , co - created by Andrew Probert and David A . Kimble . The CMU was designed by Probert for . He later remarked , " " The work bee turned out just fine . " " The studio model of the CMU was filmed in the summer of , on one of Douglas Trumbull ' s stages at Future General Corporation . ( " " , p . 206 ) Despite being proud of the CMU ' s design , Probert also felt that , in " The Motion Picture " , not enough articulation was shown in the craft . For instance , he believed that " it would have been fun " to see the CMUs enter a garage area that was included in the film ' s drydock . " " There were supposed to have been numerous Bees , doing whatever tasks with their manipulator arms , or towing things , or whatever , and they didn ' t show enough of that , " " Probert commented . " " And [ . . . ] I would have liked to have seen them drifting , or moving , or gliding / crabbing sideways through space , or rotating . They do have one that kind of rolls . . . but there should have been a lot more of that . " " An unused design for the " Enterprise " cargo / shuttlebay showed several docking ports where CMUs could attach to the ship , which were described in " Mr . Scott ' s Guide to the Enterprise " . The CMU was additionally seen in footage recycled in and during the " Enterprise " - B launch in . The craft was physically brought to the 24th century when it was included in a montage of different scenes during the main titles of , beginning with that series ' fourth season . These scenes were also used for external shots of the station in various episodes . A computer - generated model was also created , and seen at Utopia Planitia during the flashbacks to the ' s launch during . Probert designed a follow - up craft to the CMU , dubbed the Sphinx Workpod , during the first season of " Star Trek : The Next Generation " . Although it was never built as a miniature or explicitly seen , it may have been included in the matte painting of Starbase 74 in . The new workpod was also featured in the " " and " " . Apocrypha . In " " s Borg Invasion 4D exhibit , Sphinx Workpods can clearly be seen repairing Copernicus Station after its brief encounter with a Borg cube . It remains the most visible and intricate use of this design . Other similar craft to the CMU include the Arkaria shuttle seen in and the aforementioned vehicles . In the " " game series , Work Bees construct the Federation installations .