Energy storage for powering fine adjustment systems in hermetically sealed ultra-precision devices

Ultra-precision devices are often operated in hermetically sealed chambers to avoid external disturbances and maximize their performance. The remaining disturbing effects are mitigated through compensation or corrective methods. Compensation is frequently done in form of in-situ fine mechanical adjustments of highly sensitive units. Such adjustment systems utilize electromechanical drives to transform electrical energy into an intended motion. Electric cables are used as energy and signal carriers from an external control unit. The associated disturbing effects limit the adjustability. In particular, cable connections act as mechanical coupling elements, introducing indeterminate and time-varying forces. This paper deals with the conceptual design of a fine adjustment system for ultra-precision devices with an integrated energy storage. A spring-based mechanical energy storage system controlled by an optical signal is found to be the most suitable solution for the targeted field of application. The integration of an energy storage in the adjustment system to avoid electric cables and their disturbance effects will significantly improve the quality and stability of the adjustment and further increase the performance of precision devices.