Several forms of X-Y Guiders are available.
The Guide-Acquire-Modules (GAMs) are provided with X-Y stages ranging from a manually moved guide probe to a remotely controlled (or by computer) X-Y -Focus stage with position encoding.
Custom designed X-Y-Focus stages are also available such as the very low profile system built for the University of Texas Lunar ranging station. Typically, a X-Y stage is needed to allow off axis guiding for long integrations (or exposures) when performing direct imaging.