Walter D'Ambrogio

Regularisation Techniques for Dynamic Model Updating using Input Residual

The updating process to correct finite element models using experimental data is generally an ill conditioned problem. The method here presented is based on the use of the input residual, that presents some important advantages over other proposed techniques. The actions required to limit the solution instability due to ill conditioning are discussed. The importance of using regularisation techniques to minimise the influence of experimental errors is demonstrated. Several procedures are analysed through simulated and experimental tests, finally showing that the most reliable results are obtained using a priori information and the singular values truncation technique based on the minimisation of the output residual.

Development of a pneumatic soft actuator as a hand finger for a collaborative robot

Pneumatic soft actuators produce flexion and meet the new needs of collaborative robotics, which is rapidly emerging in the industry landscape 4.0. The soft actuators are not only aimed at industrial progress, but their application ranges in the field of medicine and rehabilitation. Safety and reliability are the main requirements for coexistence and human-robot interaction; such requirements, together with the versatility and lightness, are the precious advantages that is offered by this new category of actuators. The objective is to develop an actuator with high compliance, low cost, high versatility and easy to produce, aimed at the realization of the fingers of a robotic hand that can faithfully reproduce the motion of a real hand. The proposed actuator is equipped with an intrinsic compliance thanks to the hyper-elastic silicone rubber used for its realization; the bending is allowed by the high compliance of the silicone and by a square-meshed gauze which contains the expansion and guides the movement through appropriate cuts in correspondence of the joints. A numerical model of the actuator is developed and an optimal configuration of the five fingers of the hand is achieved; finally, the index finger is built, on which the experimental validation tests are carried out.