On the Validation of SPDM Task Verification Facility

TLDR

The SPDM task verification facility, developed by the Canadian Space Agency, enables ground‑based testing of the special purpose dexterous manipulator’s contact dynamics for ISS maintenance tasks that cannot be performed in 3‑D on Earth due to gravity. This paper presents a methodology for validating that ground‑based, hardware‑in‑the‑loop simulation facility. The facility drives a hydraulic robot using a high‑fidelity SPDM truth model and evaluates techniques to ensure the simulation preserves the robot’s dynamics for contact tasks. The study produced a practical validation strategy with detailed test cases and quantitative criteria for judging the simulation’s fidelity. © 2004 Wiley Periodicals, Inc.

Abstract

This paper describes a methodology for validating a ground-based, hardware-in-the-loop, space-robot simulation facility. This facility, called “SPDM task verification facility,” is being developed by the Canadian Space Agency for the purpose of verifying the contact dynamics performance of the special purpose dexterous manipulator (SPDM) performing various maintenance tasks on the International Space Station because the real SPDM cannot be physically tested for 3D operations on the ground due to the gravity. The facility uses a high-fidelity SPDM mathematical model, known as the “truth model” of the space robot, to drive a hydraulic robot to mimic the space robot performing contact operations. In this research different techniques were studied for practically verifying that the complex simulation facility preserves the dynamics of the truth model of the space robot for space-representative contact robotic tasks. Based upon the study and many years of experience in developing and verifying space robotic systems, a practical validation strategy including detailed test cases was developed along with a set of quantitative criteria for judging the validation test results. © 2004 Wiley Periodicals, Inc.