Towards Measurement of Advanced Mobile Manipulator Performance for Assembly Applications
Roger V. Bostelman, YaShian Li-Baboud, Soocheol Yoon, Mili Shah, Omar Y. Aboul-Enein
Advanced mobile manipulators offer the manufacturing industry the potential of a highly flexible system to perform precision assembly tasks where the environment and the system are subject to uncertainties. Developing precision performance measurement capabilities supports the advancement of manipulator-vehicle coordination, precision and accuracy robustness. The National Institute of Standards and Technology (NIST), Intelligent Systems Division (ISD) developed a measurement methodology for advanced mobile manipulators, mobile robots with an onboard robot arm, each from a different manufacturer and with a different controller. The measurement methodology is designed to assess the performance of mobile manipulators for manufacturing applications such as assembly. The methodology uses an artifact designed at NIST in conjunction with an optical tracking system (OTS), the mobile base controller, which measured the base position and orientation and the manipulator end-of-arm tool (EOAT) position uncertainty. The experimental data collected, using three different system computers, was timestamped using local clocks synchronized via the local area network (LAN) to ensure proper data stream alignment. The mobile manipulator system, the experimental methodology, the analysis of the data, and the results of the mobile manipulator performance measurements using the novel artifacts are described in this paper. The results demonstrate a methodology for assessing the mobile manipulator uncertainty using the artifact method and that for the system tested, detection of 2 mm diameter fiducials can be achieved after registration. The measurement metrics included mobile base stability.