LIMITATIONS OF HARDWARE-IN-THE-LOOP SIMULATIONS OF SPACE ROBOTICS DYNAMICS USING INDUSTRIAL ROBOTS

Abstract

The utilization of space robotics components in operational missions requires intensive pre-mission simulations, especially if dynamic influences will occur in the robotic manipulator, in its platform and the handled objects. Forces and torques are caused by manipulator activities and influences of the attitude control system of the satellite platform and lead to deformations and oscillations of elastic system components. To cope with these problems in the first step software simulations of the kinematic and dynamic system behaviour have to be performed. Due to uncertainties in the modelling of tools, sensors and contact mechanics it would be advantageous to extend the simulation to a hybrid one integrating available flight hardware in the simulation loop. To simulate the manipulator's endeffector motion an industrial robot is used. However integrating hardware requires real-time conditions of the simulation. Due to limitations of the sampling rate and dead times in the signal flow instabilities of the simulations may occur depending of the dynamics of the handled object.