-- Explained
local dir_string = 'Pan.Tilt.Mesh'
local dir_tab = {}
for x in dir_string:gmatch('[^.]+') do -- ^. meaning not . and + meaning until interupted by .
    table.insert(dir_tab) -- add the string to the table
end
-- dir_tab is now {'Pan','Tilt','Mesh'}
-- it essentially does the opposite as table.concat(dir_tab, '.')

local d = workspaceb -- Set the starting location
for k, v in pairs({'Pan','Tilt','Mesh'}) -- The gmatch pattern essentially seperates it into the table specified in pairs()
    d = d[v] -- set current location to the child with the name v of current location
end
print(d:GetFullName()) -- > game.Workspace.Pan.Tilt.Mesh