Space graspers are complex systems, composed by robotic arms accommodated on an orbiting platform. In order to fulfill the maneuvers requirements, it is necessary to properly model all the forces acting on the space robot. A fully nonlinear model is used to describe the dynamics, based on a multibody approach. The model includes the orbital motion, gravity gradient, aerodynamic effects, as well as flexibility of the links. The present paper aims to design, thanks to nonlinear optimization algorithms, a class of maneuvers, that, given the same target to be grasped, are characterized by different mission objectives. A given grasping mission can be performed with the only objective to minimize the power consumption. Minimum time maneuvers can be also a frequent scenario. In this case, however, large elastic displacements should be expected, possibly leading to an inaccurate positioning of the end effector. Therefore different design strategies can require that the maneuver is accomplished with minimum vibration amplitude at the end effector. Performance of the different strategies is analyzed in terms of control effort, trajectory errors, flexible response of the manipulator, computational cost.
Optimal manoeuvring of a flexible space manipulator for a class of objectives / Toglia, Chiara; Sabatini, Marco; Gasbarri, Paolo; Palmerini, Giovanni Battista. - STAMPA. - 7:(2009), pp. 5489-5499. (Intervento presentato al convegno 60th International Astronautical Congress 2009, IAC 2009 tenutosi a Daejeon nel 12 October 2009 through 16 October 2009).
Optimal manoeuvring of a flexible space manipulator for a class of objectives
TOGLIA, CHIARA;SABATINI, MARCO;GASBARRI, Paolo;PALMERINI, Giovanni Battista
2009
Abstract
Space graspers are complex systems, composed by robotic arms accommodated on an orbiting platform. In order to fulfill the maneuvers requirements, it is necessary to properly model all the forces acting on the space robot. A fully nonlinear model is used to describe the dynamics, based on a multibody approach. The model includes the orbital motion, gravity gradient, aerodynamic effects, as well as flexibility of the links. The present paper aims to design, thanks to nonlinear optimization algorithms, a class of maneuvers, that, given the same target to be grasped, are characterized by different mission objectives. A given grasping mission can be performed with the only objective to minimize the power consumption. Minimum time maneuvers can be also a frequent scenario. In this case, however, large elastic displacements should be expected, possibly leading to an inaccurate positioning of the end effector. Therefore different design strategies can require that the maneuver is accomplished with minimum vibration amplitude at the end effector. Performance of the different strategies is analyzed in terms of control effort, trajectory errors, flexible response of the manipulator, computational cost.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.