This work deals with modeling and tracking of mechanical systems which are given as kinematic chains with restricted degrees of freedom. Such systems may involve many joints, but due to additional restrictions or mechanical properties the joints depend on each other. So-called closed-chain or parallel manipulators are examples for kinematic chains with additional constraints. Though the degrees of freedom are limited, the complexity of the dynamic equations increases rapidly when studied analytically. In this work, we suggest to avoid this kind of analytic integration of interconnection constraints and instead to model them numerically via soft constraints.