Ultrasound probing device comprising: - a box, - locating means designed to provide a position P B/O of the box in relation to a reference frame associated with an object to be examined, - means (114, 138) for determining a delay law on the basis of a desired position of a focal point in relation to a reference frame associated with the box, wherein this desired position is represented by focusing parameters referenced P F/B, - control means (114, 146) designed to provide control signals on the basis of the delay law, - transducers (120 1...120 N) attached to the box, designed to receive control signals and, in response, to transmit ultrasonic waves in the object which are delayed with respect to each other according to the delay law such that they focus at the focal point defined by the focusing parameters P F/B, characterised in that: - it comprises means for storing: • predetermined positions (S (i)) on a desired path of the box in relation to the reference frame associated with the object, and • predefined associations of several different desired positions (P ref (i) F/B) of the focal point in relation to the reference frame associated with the box at several different positions among said predetermined positions (S (i)) on this desired path, - it further comprises means for updating the desired position (P ref (i) F/B) of the focal point in relation to the reference frame associated with the box and thus the corresponding focusing parameters P F/B based, on the one hand, on said stored predefined associations and, on the other hand, on the position P B/O of the box, and - the means for determining (114, 138) are designed for an update of the delay law based on the update of the desired positon of the focal point in relation to the reference frame associated to the box and on the corresponding focusing parameters P F/B. - a box, - locating means designed to provide a position P B/O of the box in relation to a reference frame associated with an object to be examined, - means (114, 138) for determining a delay law on the basis of a desired position of a focal point in relation to a reference frame associated with the box, wherein this desired position is represented by focusing parameters referenced P F/B, - control means (114, 146) designed to provide control signals on the basis of the delay law, - transducers (120 1...120 N) attached to the box, designed to receive control signals and, in response, to transmit ultrasonic waves in the object which are delayed with respect to each other according to the delay law such that they focus at the focal point defined by the focusing parameters P F/B, - it comprises means for storing: • predetermined positions (S (i)) on a desired path of the box in relation to the reference frame associated with the object, and • predefined associations of several different desired positions (P ref (i) F/B) of the focal point in relation to the reference frame associated with the box at several different positions among said predetermined positions (S (i)) on this desired path, • predetermined positions (S (i)) on a desired path of the box in relation to the reference frame associated with the object, and • predefined associations of several different desired positions (P ref (i) F/B) of the focal point in relation to the reference frame associated with the box at several different positions among said predetermined positions (S (i)) on this desired path, - it further comprises means for updating the desired position (P ref (i) F/B) of the focal point in relation to the reference frame associated with the box and thus the corresponding focusing parameters P F/B based, on the one hand, on said stored predefined associations and, on the other hand, on the position P B/O of the box, and - the means for determining (114, 138) are designed for an update of the delay law based on the update of the desired positon of the focal point in relation to the reference frame associated to the box and on the corresponding focusing parameters P F/B.