We investigate the exploitation of linear models of camera-object interacti
on for an efficient modeling and control of image-based visual servoing sys
tems. The approach includes a method for coping with those representation a
mbiguities typical of Linear interaction models which may affect both plann
ing and control. The implementation of an eye-in-hand servoing system based
on affine camera models and using image contours as relevant visual featur
es is described and discussed. The system, including an image planner, a tw
o-dimensional/three-dimensional (2-D/3-D) controller, and a visual analysis
module, allows an intuitive specification and execution of relative positi
oning tasks w.r.t. still or moving rigid objects. Results of real-time expe
riments with a robotic platform featuring a PUMA manipulator provide a furt
her insight into characteristics and performance of affine visual servoing
systems.