A comparative study on continuous contact force models for constrained multibody systems

Fundacao para Ciencia e a Tecnologia (FCT) - BIOJOINTS - Development of advanced biological joint models for human locomotion biomechanics (PTDC/EME-PME/099764/2008), DACHOR - Multibody Dynamics and Control of Hybrid Active Orthoses (MITPt/BSHHM/0042/2008).