Parallel robots are used in rehabilitation, because they have advantages over serial robots. OpenSim let users add constraints. In parallel robotics field, geometric constraints are very important for analysis. The mechanical interaction between human body and robots is a growing research theme. This approach can be used as a tool. First,capturing information about human body, then, applying the toolchain analysis in OpenSim, scaling, kinematics and dynamics. Finally integrate the models and simulate the impact in forces and movements of robot in the musculoskeletal model.