Design of compliant mechanisms based on rigid-body mechanisms. - In: Romanian journal of technical sciences, ISSN 2601-5811, Bd. 67 (2022), 1, S. 61-78
The design of compliant mechanisms is a much more complicated task than their analysis. Consequently, there are many more methods available for the analysis of compliant mechanisms than for their synthesis. In this article, a contribution to the synthesis of compliant mechanisms is made by presenting a comparison of two different methods for their design. In both methods rigid-body systems are used as a basis for compliant mechanisms. Depending on the task of the compliant mechanism, one of these methods can be selected and applied. The deviations between the results of the used theory and measurement results as well as FEM results are less than 5.5 % for displacements and acting forces. Selected mechanisms for the realization of a straight-line motion of a point and for given relative motions are presented as examples.
An analytical method for calculating the natural frequencies of spatial compliant mechanisms. - In: Mechanism and machine theory, Bd. 175 (2022), 104939, S. 1-17
Compliant mechanisms are becoming increasingly important in both research and industry. The design and the static analysis of such mechanisms has made much progress in recent years, yet comparatively little research has been done on their dynamic behaviour. The aim of this paper is to advance the dynamic analysis of spatial compliant mechanisms by pursuing the calculation of their natural frequencies. So far, their determination is only possible with time-consuming 3D-FEM simulations or via pseudo-rigid-body models and Lagrangian equations. An analytical method is developed to simplify and accelerate the calculation of the natural frequencies of compliant mechanisms. The method is integrated into an algorithm on which a graphical user interface is developed to allow the design and calculation of the system in the most time efficient and intuitive way. The results are verified by 3D-FEM simulations and validated through an experiment. The evaluation shows good agreement with the reference models. The results of this paper allow a reliable and efficient calculation of natural frequencies and serve to facilitate further work regarding the dynamic analysis of compliant mechanisms.
Modeling of corner-filleted flexure hinges under various loads. - In: Mechanism and machine theory, Bd. 175 (2022), 104937, S. 1-11
Compliant mechanisms are widely applied in precision engineering, measurement technology and microtechnology, due to their potential for the reduction of mass and assembly effort through the integration of functions into fewer parts and an increasing motion repeatability through less backlash and wear, if designed appropriately. However, a challenge during the design process is the handling of the multitude of geometric parameters and the complex relations between loads, deformations and strains. Furthermore, some tasks such as the dimensioning by means of optimization or the modeling for a controller design require a high number of analysis calculations. From this arises the need for sufficient computational analysis models with low calculation time. Existing studies of analysis models are mostly based on selected load cases, which may limits their general validity. The scope of this article is the comparison of models for the analysis of corner-filleted flexure hinges under various loads, to determine their advantages, disadvantages and application fields. The underlying methods of the study can further be used to evaluate future models based on a broad selection of possible load cases.
Development of a calculation tool for the natural frequencies of planar compliant mechanisms :
Entwicklung eines Berechnungstools für die Eigenfrequenzen von planaren nachgiebigen Mechanismen. - In: Achte IFToMM D-A-CH Konferenz 2022, (2022), insges. 2 S.
Analytical calculation of the deformation behavior of spatial compliant mechanisms :
Analytische Berechnung des Verformungsverhaltens räumlicher nachgiebiger Mechanismen. - In: Achte IFToMM D-A-CH Konferenz 2022, (2022), insges. 2 S.
CoMSys - a GUI-based calculation tool for the analysis and optimisation of compliant mechanisms :
CoMSys - ein GUI-basiertes Berechnungstool zur Analyse und Optimierung nachgiebiger Mechanismen. - In: Achte IFToMM D-A-CH Konferenz 2022, (2022), insges. 2 S.
On the influence of geometrical deviations of flexure hinges on the trajectory behaviour of straight-line compliant mechanisms for ultra-precision applications :
Zum Einfluss von geometrischen Abweichungen von Festkörpergelenken auf das Bahnverhalten von nachgiebigen Geradführungsmechanismen für Ultrapräzisionsanwendungen. - In: Achte IFToMM D-A-CH Konferenz 2022, (2022), insges. 2 S.
Improving energy efficiency of bipedal walking using nonlinear compliant mechanisms. - In: Proceedings in applied mathematics and mechanics, ISSN 1617-7061, Bd. 21 (2021), 1, e202100197, S. 1-3
A method to improve the energy efficiency of a bipedal robot by coupling its thighs with compliant smart mechanisms is introduced. The walking gaits are driven by electric motors in its revolute joints, whose reference trajectories are generated via numerical optimization. The optimized nonlinear characteristic of the compliant mechanism modifies the free oscillation frequency of the system that matches the current double step frequency even under different conditions, which results in a very high energy efficiency.
Synthesis of a compliant system from a given curve :
Synthese eines Nachgiebigen Systems mit gegebener Kennlinie. - In: IFToMM D-A-CH Konferenz 2021 der IFTOMM Member Organizations Austria, Germany, Switzerland, (2021), S. 87-88
Das Biege-Torsions-Steifigkeitsverhältnisses von Festkörpergelenken mit Standard- und Polynomkonturen :
The bending-torsion-stiffness ratio of flexure hinges with common and polynomial notch shapes. - In: IFToMM D-A-CH Konferenz 2021 der IFTOMM Member Organizations Austria, Germany, Switzerland, (2021), S. 74-75