In this paper a 4-4 cable-based system is presented for an application of aiding elderly people or patients with disabilities at lower limbs, in standing up and sitting operations. Cable-based manipulators have very good kinematic and dynamic characteristics, and they also show other properties such as good transportability and low-cost construction, which make them also suitable for medical applications and rehabilitation. The proposed application is analyzed through a kinetostatic analysis and simulation of the manipulator. An experimental validation of the proposed application is presented by means of an existent prototype, which is called CALOWI (CAssino LOw-cost WIre robot) that is available at LARM in Cassino. A low-cost system for tension monitoring has been used to monitor the forces in the cables during the experimental tests.