A fundamental aspect of grasp analysis is the problem of formalizing stable grasps like an optimization problem and defining some cost functions on the set of possible solutions, used to select a solution that minimizes the problem. Those cost functions have the aim to predict the grasp forces during grasping, considering the geometry of the problem, the grasping forces and their spatial disposition, minimizing energy expenditure and maximizing stability of the grasp. Maximizing stability and minimizing energy expenditure are contrasting goals and are not pursued simultaneously. In this work, we use a model of the human hand with only the first three fingers (thumb, index and middle or ring) , because those fingers have more importance during a precision grasp. A model with only three fingers allows us to reduce the complexity of the problem, assuring at the same time to optimize grasp stability of the manipulated object with the minimum energy expenditure. Each cinematic chain is described with 4 links and 4 revolute joints, for a total of 12 DoF. This research theme is strictly connected with the themes Virtual Manipulation and Virtual Grasping.