Stiffness Evaluation of a Hexapod Machine Tool with Integrated Force Sensors
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TU Dresden, Institute of Mechatronic Engineering, Chair of Machine Tools Development and Adaptive Controls, Dresden, Germany
Submission date: 2019-11-13
Acceptance date: 2020-01-16
Online publication date: 2020-02-26
Publication date: 2020-03-06
Journal of Machine Engineering 2020;20(1):58-69
Today, in-process force measurement is required by many manufacturing applications, such as process monitoring, quality assurance, or adaptive process control. A very promising force measurement approach bases on sensor-integration into the machine structure and is particularly suitable for hexapod structures and kinematics, where it allows a measurement in 6 degrees of freedom. On the other hand, a sensor integration also affects the machine. Especially for strain-gauge-based force sensors, a stiffness reduction is predicted, as their measuring principle requires a deformation. The practical consequences of these influences are investigated in this contribution. In particular, this work presents extensive experimental studies of the stiffness change caused by sensor integration for a single hexapod strut as well as for the complete hexapod machine tool. The results are evaluated in comparison to compliances of other components, such as the kinematic joints, and to stiffness changes resulting from sensor-integration into the end-effector or the application of a commercial force/torque sensor at the end-effector. In conclusion, the studies support the approach of structure-integrated force measurement for parallel kinematics, as the stiffness loss is rather small in many cases.
The authors are grateful to the German Research Foundation (DFG) who supported this work with the projects "Fundamentals for structure-integrated measurement and control-integrated processing of spatial forces and torques in machine tools" (DFG No 202081830) and “Fundamentals for the use of eccentric joints in parallel kinematic machine tools” (DFG No 53530748). Further, the authors want to thank the editors and reviewers for their helpful comments and constructive suggestions with regard to the revision of this paper.
ALTINTAS Y., PARK S., 2004, Dynamic Compensation of Spindle-Integrated Force Sensors, CIRP Annals – Manufacturing Technology, 53/1, 305–308.
HESSELBACH J., BEHRENS B.A., DIETRICH F., POELMEYER J., RATHMANN S., 2008, Regelunskonzept für eine Umformmaschine auf Basis einer Parallelstruktur und simulative Ermittlung von prozessgerechten Maschinenparametern, Fertigungsmaschinen mit Parallelkinematiken, Shaker Verlag, 307–322.
DENKENA B., DAHLMANN D., BOUJNAH H., 2016, Sensory Workpieces for Process Monitoring – An Approach, Procedia Technology, 26, 129–135.
FRIEDRICH C., KAUSCHINGER B., IHLENFELDT S., 2019, Spatial force measurement using a rigid hexapod-based end-effector with structure-integrated force sensors in a hexapod parallel kinematic, Measurement, 145C, 350–360.
DESOGUS S., GERMAK A., MAZZOLENI F., QUAGLIOTTI D., BARBATO G., BARBIERI A., BIGOLIN G., BIN C., 2010, Developing multicomponent force transducers at INRiM, IMEKO World Congress, 17–19.
GENTA G., GERMAK A., BARBATO G., LEVI R., 2016, Metrological characterization of an hexapod-shaped Multicomponent Force Transducer, Measurement, 78, 202–206.
KANG C.-G., 2001, Closed-form force sensing of a 6-axis force transducer based on the Stewart platform, Sensors and Actuators A: Physical, 90/1, 31–37.
NITSCHE J., BAUMGARTEN S., PETZ M., RÖSKE D., KUMME R., TUTSCH R., 2017, Measurement uncertainty evaluation of a hexapod-structured calibration device for multi-component force and moment sensors, Metrologia, 54/2, 171–183.
OELHYDRAULIK HAGENBUCH AG, 2017, Kräfte messen mit Hexamove-Konzept, Produktprospekt: Hexamove – Bewegung leichtgemacht, 16, 17–17.
PALUMBO S., GERMAK A., MAZZOLENI F., DESOGUS S., BARBATO G., 2016, Design and metrological evaluation of the new 5 MN hexapod-shaped multicomponent build-up system, Metrologia, 53/3, 956–964.
RÖSKE D., 2003, Metrological characterization of a hexapod for a multi-component calibration device, XVII IMEKO World Congress (Metrology in the 3rd millennium), 347–351.
SEIBOLD U.S., 2013, An advanced force feedback tool design for minimally invasive robotic surgery, PhD thesis, Technische Universität München.
FRIEDRICH C., KAUSCHINGER B., IHLENFELDT S., 2016, Decentralized structure-integrated spatial force measurement in machine tools, Mechatronics, 40, 17–27.
KAUSCHINGER B., 2006, Verbesserung der Bewegungsgenauigkeit an einer Parallelkinematik einfacher Bauart, PhD thesis, TU Dresden.
ARCHENTI A., NICOLESCU M., CASTERMAN G., HJELM S., 2012, A new method for circular testing of machine tools under loaded condition, Procedia CIRP, 1, 575–580.
FRINDT M., 2001, Modulbasierte Synthese von Parallelstrukturen für Maschinen in der Produktionstechnik, PhD thesis, TU Braunschweig.
KREFFT M., 2006, Aufgabenangepasste Optimierung von Parallelstrukturen für Maschinen in der Produktionstechnik, PhD thesis, TU Braunschweig.
MERLET J.P., 2006, Parallel robots, 128. Springer Science & Business Media.
CARBONE G., 2011, Stiffness analysis and experimental validation of robotic systems, Frontiers of Mechanical Engineering, 6/2, 182–196.
NEUGEBAUER R. editor, 2006, Parallelkinematische Maschinen: Entwurf, Konstruktion, Anwendung, VDI-Buch, Springer.
RUDOLPH H., 2012, Ein Beitrag zur Analyse der nichtlinearen Systemdynamik in der Entwurfsphase von Werkzeugmaschinen, PhD thesis, TU Dresden.
GROSSMANN K., KAUSCHINGER B., RIEDEL M., 2013, Optische Verlagerungsmessung an Kardangelenken, WT Online, 103, 402–409.
GROSSMANN K., KAUSCHINGER B., RIEDEL M., 2012, Exzentrische Gelenke für parallelkinematische Werkzeugmaschinen, ZWF, 01–02, 25–32.
GROSSMANN K., KAUSCHINGER B., 2012, Eccentric universal joints for parallel kinematic machine tools: variants and kinematic transformations, Production Engineering, 6/4-5, 521–529.
CHEN S.F., KAO I., 2000, Conservative Congruence Transformation for Joint and Cartesian Stiffness Matrices of Robotic Hands and Fingers, The International Journal of Robotics Research, 19/9, 835–847.
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