This paper addresses the important issue of estimating realistic grasping p
ostures, and presents a methodology and algorithm to automate the generatio
n of hand and body postures during the grasp of arbitrary shaped objects. P
redefined body postures stored in a database are generalized to adapt to a
specific grasp using inverse kinematics. The reachable space is represented
discretely dividing into small subvolumes, which enables to construct the
database. The paper also addresses some common problems of articulated figu
re animation. A new approach for body positioning With kinematic constraint
s on both hands is described. An efficient and accurate manipulation of joi
nt constraints is presented. Obtained results are quite satisfactory, and s
ome of them are shown in the paper. The proposed algorithms can find applic
ation in the motion of virtual actors, all kinds of animation systems inclu
ding human motion, robotics and some other fields such as medicine, for ins
tance, to move the artificial limbs of handicapped people in a natural way.