This work presents a novel protocol for analyzing ankle kinematics and characterizing its three-dimensional workspace using advanced motion capture techniques. The ankle, a key joint for mobility and balance, exhibits complex biomechanics that require accurate modeling for applications in rehabilitation and assistive device design. Using a VICON system and standardized marker placement, ankle motion was recorded during dorsiflexion-plantarflexion, inversion-eversion, and adduction-abduction tasks. A simplified kinematic model with cylindrical joints enabled the analysis of rotational and translational displacements between the leg, foot, and shoe. The results did not reveal significant relative movements between the knee and ankle joints, which were modeled as cylindrical joints; however, appreciable relative movements were observed between the foot and the shoe, highlighting the importance of accounting for foot-shoe decoupling. These observations support the validity of the proposed kinematic model and provide valuable insights for the development of wearable rehabilitation devices. The proposed methodology lays the groundwork for deriving the ankle’s functional workspace and supports future advancements in clinical and engineering contexts.