Adaptive control methods can reduce the influence of structured disturbances on the positioning accuracy of nanopositioning devices. In this project, various approaches are to be investigated to improve the control accuracy. In addition, novel concepts of reset controllers for a robust nominal controller are to be investigated. There, friction effects have to be taken into account, causing hysteresis in the input/output representation. A key aspect is the stability investigation of an adaptive reset system, which results from the hybrid nominal controller and the adaptive disturbance compensation. The nominal reset controller is to be designed and tested simulatively with regard to the characterised disturbances. Finally, the elaborated concept is to be tested experimentally during positioning and can be adapted to further control tasks in the context of nanofabrication (e.g. control of laser power). Key categories:
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Cantilevers used for force measurement are currently calibrated in calibration setups by determining the force-displacement characteristic in a metrologically traceable way. There, a large uncertainty contribution is the relocation of the cantilever from the calibration setup to the actual application. Tilting and positioning deviations can only be estimated and impact the measurement uncertainty significantly in the application. In this project, approaches for a metrologically traceable, continuous in-situ calibration of cantilevers shall be studied to allow a seamless calibration and operation. The results can be experimentally investigated in NanoFab nanopositioning devices or in the cantilever calibration facility and are expected to improve the capabilities and the precision of cantilever-based nanofabrication and nanometrology techniques. Key categories:
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At NanoFab, a 6D nanopositioning system was realised, which is based on a combination of a 200 mm planar drive with a vertical system consisting of three stroke modules. The goal of this project is to expand this 6D positioning system into a measuring and processing system, investigate it and, in particular, characterize it metrologically. For this purpose, concepts for the integration of a probing system (e.g. atomic force microscopy, plasmonic and scanning probe lithography) into the existing set-up, an improvement of the dynamics and the realisation of a force-controlled probing mode are necessary. In addition to that, the effects of external and internal disturbances (vibration, temperature, pressure, air flow, etc.) are to be investigated model-based and experimentally. On this basis, new metrology concepts are to be developed and investigated in order to reduce the measurement uncertainty. Key categories:
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