Self-centering probes with parallel kinematics to verify machine-tools

• Published in: Precision engineering 2006-04, Vol.30 (2), p.165-179
• Main Authors: Trapet, Eugen, Aguilar Martín, Juan-José, Yagüe, José-Antonio, Spaan, Henny, Zelený, Vit
• Format: Article
• Language: English
• Subjects: Applied sciences; Ball artifacts; Exact sciences and technology; Industrial metrology. Testing; Machine-tools; Mechanical engineering. Machine design; Parallel kinematics; Precision engineering, watch making; Self-centering probe; Verification
• ISSN: 0141-6359; 1873-2372
• DOI: 10.1016/j.precisioneng.2005.07.002

In this paper, a new type of self-centering probe is presented to verify the performance of machine-tools in an efficient and rapid way using ball artifacts. A self-centering probe is placed in the spindle of the machine-tool and a ball artifact on the work table. The probe is moved to the calibrated center positions of the balls of the reference artifact. The probe touches these balls and, in a single measurement, it provides the X, Y, Z offset of the actual machine position from the desired (programmed) position. A non-conventional probe design has been chosen: three independently movable probe styli form a miniature coordinate measuring machine with parallel kinematics. The development process of two variants of such a self-centering probe is presented in this paper. The results obtained in laboratory tests show a repeatability of less than 0.5 μm and an error range of less than 2 μm throughout the large measurement range (2 mm × 2 mm × 2 mm) of the probe.