1. A robot apparatus comprising: an output unit configured to display an image including an object on a screen; an input unit configured to receive, based on an operation performed by a user, a first specification relating to an approximate range including the object in the image; an object extraction unit configured to extract information regarding a two-dimensional contour of the object based on the first specification received by the input unit; a position and attitude estimation unit configured to estimate information regarding a three-dimensional position and attitude of the object based on the information regarding the two-dimensional contour; a holding unit; and a holding planning unit configured to plan, without receiving a stored shape model from a database, a trajectory of the holding unit for holding the object based on the estimated information regarding the three-dimensional position and attitude of the object.