This paper presents a method for the design of compliant micro transmission mechanisms which multiply the motion frequency of a cyclic input motion. Compliant embodiments are generated based on exploiting the singularity in a double-slider mechanism, which provides building blocks with a frequency multiplication factor of two. It is shown that the proposed building blocks can be concatenated for higher frequency multiplication ratios, and that the maximum number of blocks is limited by the desired travel range of the output. The input-output kinematics and the different stiffness characteristics of the building blocks are discussed based on pseudo-rigid-body model (PRBM). To validate the building block approach, a compliant micro transmission mechanism is presented which quadruples the frequency of a cyclic rectilinear input motion. Furthermore, a micro scale prototype was dimensioned and fabricated out of silicon using deep reactive ion etching to evaluate the design experimentally and validate the PRBM and finite element models. [2017-0318]@en

Usage of compliant micromechanical oscillators has increased in recent years, due to their reliable performance despite the growing demand for miniaturization. However, ambient vibrations affect the momentum of such oscillators, causing inaccuracy, malfunction, or even failure. Therefore, this paper presents a compliant force-balanced mechanism based on rectilinear motion, enabling usage of prismatic oscillators in translational accelerating environments. The proposed mechanism is based on the opposite motion of two coplanar prismatic joints along noncollinear axes via a shape-optimized linkage system. Rigid-body replacement with shape optimized X-bob, Q-LITF, and LITF joints yielded a harmonic (R>0.999), low frequency (f=27 Hz) single piece force-balanced micromechanical oscillator (Ø 35 mm). The experimental evaluation of large-scale prototypes showed a low ratio of the center of mass (CoM) shift compared to the stroke of the device (≈ 0.01) and proper decoupling of the mechanism from the base, as the oscillating frequency of the balanced devices during ambient disturbances was unaffected, whereas unbalanced devices had frequency deviations up to 1.6%. Moreover, the balanced device reduced the resultant inertial forces transmitted to the base by 95%.@en

Micro-electromechanical systems (MEMS) often require tuning to correct for fabrication errors such as changed dimensions or to adapt for a different scenario such as changed temperature. To prevent continuous power consumption for maintaining system behavior, a locking system can be added which does not require any power during operation. A new comb finger locking mechanism design is proposed using an orthogonal spring force on a moving shuttle to generate a locking force in the motion direction through friction. Multiple contact points are placed in line with the spring force to increase the locking force in a volumetric efficient way. The spring is optimized for high locking force but low sensitivity to fabrication errors. Mechanism design is illustrated and successfully tested using a case study example.

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Usage of compliant micro mechanical oscillators has increased in recent years, due to their reliable performance despite the growing demand for miniaturization. However, ambient vibrations affect the momentum of the oscillator, causing inaccuracy, malfunction or even failure of these devices. herefore, this paper presents a compliant force balanced mechanism comprising at least a prismatic joint, thereby creating the opportunity for usage of prismatic oscillators in translational accelerating environments. The proposed mechanism entails the symmetric displacement of two coplanar prismatic joints along non-collinear axes via a shape optimized linkage system. Rigid-body replacement with shape optimized X-bob, Q-LITF and LITF joints yielded a harmonic (R>0.999), low frequency (f = 27 Hz) single piece force balanced micro mechanical oscillator (∅35 mm). Experimental evaluation of large scale prototypes showed a limited ratio of the center of mass compared to the stroke of the device (≈0.01) and proper decoupling of the mechanism from the base, as the oscillating frequency of the balanced devices during ambient disturbances was unaffected, whereas unbalanced devices had frequency deviations up to 1.6%. Moreover, the balanced device reduced the resultant inertial forces transmitted to the base by 95%.@en