The overall goal of the Joint Research Project is a significant improvement of state-of-the-art measurement capabilities of multi-sensor coordinate measuring machines (CMMs) for microparts used, e.g. in automotive, medical and optical applications. The project will address the specific problems related to dimensional measurements of small complex features at high accuracy and all forms of sensors used for the measurement of microparts will be included. These specific problems have a strong influence on measurement uncertainties. The project will also address the issue of traceability, comparability, handling and fusion of measurement data from multiple sensors, which are important issues for the industrial application of multi-sensor coordinate metrology.


Microparts with complex geometry are becoming increasingly important for numerous industrial products found in many sectors, e.g. automotive, medical and telecommunications. The need for improved metrological capabilities in this field has been identified by several roadmap studies and has been expressed by instrument manufacturers and standardisation bodies. One of the most important development trends in industrial dimensional metrology, having the potential to fulfill the requirements to measure complex microparts, is multi-sensor coordinate metrology. This combines the speed of optical measurements with the accuracy and 3D capability of tactile measurements and, more recently, the ability to measure interior features using X-ray computed tomography (CT). While tactile and optical techniques are well-established for intermediate workpiece size and accuracy, less progress has been made for 3D measurement of small parts with sub-millimetre features and sub-micrometre tolerances (Microparts). The development of CT to measure microparts is still at an early phase.


The main challenges of the project are:

  • The 3D measurement of complex and ever smaller geometrical features of microparts at uncertainties well below 0.1 µm. For this, tactile sensors with smaller stylus diameters (< 50 µm) need to be further developed and characterised in full 3D.

  • For optical sensors and CT systems, traceability and comparability to tactile methods need to be assured and the accuracy needs to be increased.

  • Considering the geometrical complexity of microparts, and the large data sets produced by optical sensors and CT, intelligent handling of multi-sensor data is necessary. Therefore, intelligent data filtering and synergetic data acquisition from multiple sensors, capturing information from the same workpiece, need to be fused to produce a consistent multi-sensor data set.


Key applications of multi-sensor metrology of microparts will be demonstrated in cooperation with the industrial JRP-Partners. The key applications will be in the fields of medicine, automotive and plastic manufacturing. In addition to the demonstrations, the project and the results will be made public by a webpage, a workshop, etc. The incorporation of the project results into international standards will support the long-term impact of the project. The project will support innovative design and accelerated development of new production technologies for small mechanical components due to better measurement capabilities for geometrical specifications of micro components with improved accuracy and reliability. This will result in a reduction of manufacturing costs, in new products based on miniature components and in an increased market penetration of European manufacturers. The industrial sectors addressed by this project are mechanical engineering, measuring instrument manufacturers, process engineering and production technologies, automotive and medical.