For configuring a LabBot to function as a standard FDM 3D printer (printing things like 1.75mm filament), it is advantageous to use a motorized Z bed rather than the XY directional moving linear actuator. In this case the extruding nozzles would just move in the XY direction and the printing area would move up and down.
It is possible to have both options but for laboratory automation configurations the motorized Z bed is not a standard feature. So it is an accessory option. This thing can drop into a LabBot. It will look something like this.