This paper presents a planar parallel threedegree-of-freedom underactuated cable-driven robot. The mechanism is first described and a dynamic model is derived. The proposed mechanism does not require any mechanical (e.g. pulleys) or electrical (e.g. actuators) hardware to be mounted on the end-effector. A trajectory planning approach is developed, which is based on the natural frequency of the pendulumlike free motion (unconstrained degree of freedom). Sine-like excitation functions are used and their frequency and phase delay are determined using simulation results. A prototype is then described and experimental results are provided together with a video clip of an example trajectory. The results confirm that the mechanism can be effectively used to perform pointto-point trajectories.

This paper presents the full proof of concept of a system for capturing the light field of an object. It is based on a single high resolution camera that is moved all around the object on a cable-driven end-effector. The main advantages of this system are its scalability and low interference with scene lighting. The camera is accurately positioned along hemispheric trajectories by observing target features. From the set of gathered images, the visual hull is extracted and can be used as an approximate geometry for mapping a surface light field. The paper describes the acquisition system as well as the modeling process. The ability of the system to produce models is validated with four different objects whose sizes range from 20 cm to 3 m.

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