A method for preparing navigation information for a robot having a payload for carrying out a domestic task within a working area, the method comprising: receiving sensor information relating to said working area, including a plurality of arrays of sensor data, which correspond to images taken at different locations and/or orientations with respect to said working area by one or more cameras; receiving user-provided information designating a reference trail within said working area; and processing: said sensor information relating to said working area, including said plurality of arrays of sensor data, and said information from the user designating the reference trail, said processing step producing navigation information for said robot that sufficiently defines said reference trail such that the robot can move along said reference trail substantially autonomously, characterized in that : said step of receiving information from a user designating a reference trail within said working area comprises presenting an interface to the user, which: presents a visual representation of said plurality of arrays of sensor data to the user; and enables the user to designate said reference trail, including by presenting a visual representation of both said reference trail and said plurality of arrays of sensor data, and said visual representation of the plurality of arrays of sensor data appears as an aerial photo of the working area. receiving sensor information relating to said working area, including a plurality of arrays of sensor data, which correspond to images taken at different locations and/or orientations with respect to said working area by one or more cameras; receiving user-provided information designating a reference trail within said working area; and processing: said sensor information relating to said working area, including said plurality of arrays of sensor data, and said information from the user designating the reference trail, said processing step producing navigation information for said robot that sufficiently defines said reference trail such that the robot can move along said reference trail substantially autonomously, said sensor information relating to said working area, including said plurality of arrays of sensor data, and said information from the user designating the reference trail, said processing step producing navigation information for said robot that sufficiently defines said reference trail such that the robot can move along said reference trail substantially autonomously, characterized in that : said step of receiving information from a user designating a reference trail within said working area comprises presenting an interface to the user, which: presents a visual representation of said plurality of arrays of sensor data to the user; and enables the user to designate said reference trail, including by presenting a visual representation of both said reference trail and said plurality of arrays of sensor data, and said visual representation of the plurality of arrays of sensor data appears as an aerial photo of the working area. presents a visual representation of said plurality of arrays of sensor data to the user; and enables the user to designate said reference trail, including by presenting a visual representation of both said reference trail and said plurality of arrays of sensor data, and said visual representation of the plurality of arrays of sensor data appears as an aerial photo of the working area. <EOS>