A Passivity-Based Approach for Simulating Satellite Dynamics With Robots: Discrete-Time Integration and Time-Delay Compensation

Abstract

This article proposes a passivity-based approach for simulating satellite dynamics on a position-controlled robot equipped with a force-torque sensor. Time delays intrinsic in the computational loop and discrete-time integration degrade the behavior of the satellite dynamics reproduced by the robot. These factors can generate an energy-inconsistent simulation and can even render the system unstable. In this article, time delay and discrete-time integration effects are analyzed from an energetic perspective and compensated through a passivity-based control strategy to ensure a faithful and stable dynamic simulation with position-controlled robots. The benefit of the proposed strategy is validated by simulations and experiments on the On-Orbit Servicing Simulator (OOS-SIM), a robotic facility used for simulating free-floating dynamics.

Robotic Manipulation and Capture in Space: A Survey

“…A control strategy considering the servicing vehicle base and the manipulator as a single multi-body system subject to coordinated control was presented in Sabatini et al (2017) , with the goal of approaching and grasping a target spacecraft. In De Stefano et al (2019) , a coordinated control was presented for end-effector tracking and base regulation, while focusing on the effects due to the different sampling rates of the manipulator and base controllers, which can generate stability issues. The approach task to a tumbling target with a fully actuated free-flying robot was addressed in Mishra et al (2020) , where a cascade interconnection of a geometric EKF observer and a geometric controller were validated in simulation.…”

A Relative Dynamics Formulation for Hardware- in-the-Loop Simulation of On-Orbit Robotic Missions

“…Dyn) in Fig. 2 represents the behavior to be simulated and it is usually expressed as the dynamics of a rigid body with desired mass and inertia parameters in an absolute form [6], [18]. This means that the motion (represented by the pose g g g in Fig.…”

“…( 18) is the equation to be integrated in V V V s s s to obtain a pose to be commanded to the industrial robot, g g g s s s . Note that in (18), the Coriolis forces from the simulated scenario are mapped into the dynamics that the robot will reproduce. Furthermore, F F F b b b will be the actuation force input provided by the OBSW controller.…”

Normalized passivity control for hardware-in-the-loop with contact

“…[15] reported that using the power error has the advantages that changes in α are smoother and that there is no integration necessary to retrieve the energy error from the power error. One of the latest publications in this field is [16], where also TDPC (consideration of the energy error) is applied. There, the PO monitors only the port between the numerical part and the transfer system and regards the combination of the transfer system and the experimental part as one subsystem.…”

“…There, the PO monitors only the port between the numerical part and the transfer system and regards the combination of the transfer system and the experimental part as one subsystem. Since the former explained PO monitors both ports of the transfer system, it is able to measure exactly the amount of energy that is added to the dynamical system (numerical and experimental part) by the transfer system, whereas the PO by [16] only detects an energy increase in the numerical part. In preliminary studies, it was investigated that the two-port implementation detects instability earlier than the one-port implementation, wherefore it is expected to be more accurate.…”