Open Workshops
Workshop 1: 15:30-18:30
“Spindle for Ultra-precision Technology Applications” (facilitated by O. Riemer)
“Measuring the error motion of a hydrostatic spindle, a case study” by Guido Florussen, IBS Precision Engineering
The error motion of a precision spindle equipped with a hydrostatic bearing is investigated in this case study. Capacitance sensors are used to measure the spindle’s error motion. The noise level of these sensors however can be distorted by electromagnetic fields i.e. radiated by a (linear) motor nearby. Measures to improve the sensor noise level by grounding are investigated in this case study.
The measurement setup used will be presented together with the obtained measurement results.
“Spindle analysis – limits to precision” by Sebastian Böhl, ETH
In case of using contactless capacitive transducers to test geometric accuracy of spindles electromagnetic disturbances may reduce the performance of the measurement device, may disturb the measurement and increase measurement uncertainty due to noise. In this presentation different examples of electromagnetic interference are discussed. Furthermore, measures to reduce or eliminate specific disturbance influences are suggested in order to enable full use of the capability of the measurement device in a machine tool environment. The potential of in-situ cap tests and corresponding signal analysis is shown in order to estimate the robustness of the measurement setup against electromagnetic disturbances.
“Proper performance testing of an ultra-precision air bearing spindle” by Dr. Byron Knapp, Professional Instruments
This talk describes design and testing of a new porous graphite air bearing workholding spindle for diamond turning. This spindle must pass a variety of performance tests including static stiffness, load capacity, dynamic stiffness, broad-band vibration, balancing, error motion, and cutting tests and each test is described.
“Applications and Spindle Solutions for Ultra-Precision CNC-Machining” by Dr. R. Dupont, Levicron GmbH
- Current trends in CNC machining targeting on surface finish and higher accuracy at reduced part size
- Next generation CNC machine tool
- Aerostatic tool spindle technology to bridge the gap between ultra-precision and CNC machining
- A direct comparison
- Customer parts and applications
“Precision Balancing” by Dr. M. Bobertag, PMB GmbH
We all put much effort in our highly accurate systems. If these systems contain rotating parts, the imbalance and resulting vibration has a very high influence on the achievable quality. To optimize this quality vibration analysis of the system and balancing of rotating parts go hand in hand – tools and methods will be presented here.
Workshop 2: 15:30-18:30“Areal Surface Metrology” Prof Liam Blunt Dr Carlos Bermudez |
The seminar cover two broad areas of areal surface metrology:
The first session delivered by Carlos Bermudez of the instrument manufacturer Sensofar Metrology will cover the major techniques for capturing areal surface information. The lecture will include an overview of both contact and non-contact areal measurement technologies, with a deep study of the following ones:
- Confocal microscopy
- Focus Variation
- Optical Interferometry
- Phase Shift Interferometry (PSI)
- Coherence Scanning Interferometry (CSI)
Every measurement technique is oriented to a certain range of applications. Therefore, current state of the art is evolving towards technology fusion to make them more versatile, such as:
- Confocal Fusion
- Extended PSI (ePSI)
Finally, some future applications will be presented:
- Optical CMM
- Large Areas measurement
- Sensors, inline integration
The second session delivered by Prof Liam of the Advanced Metrology Hub University of Huddersfield UK will cover the methodologies for surface data characterisation and will include areal parameters as outlined in ISO25178. The seminar will cover the distinction between field parameters and feature parameters. In addition the ideal of the scale limited surface will be introduced as will relevant data filtering tehniques. Where appropriate the seminar will be illustrated with appropriate case study exemplars.