Actuators
Monolithic Structures for Amplifying Motion or Force
Compliant mechanisms can produce significant amplification of small deflections (65X) in a compact, high-frequency system that does not rely on resonance to achieve desired displacement. This greatly extends the applicability of smart materials actuators, which by themselves are typically limited to small strains and correspondingly small deflections (10 µm - 1000 µm). By integrating a joint-less, backlash-free compliant mechanism with a smart materials actuator, the force and stroke can be tailored to suit specific needs.
Illustrated above shows how a compliant mechanism alters the force-displacement characteristic of a smart materials or conventional actuator or actuators. The compliant mechanism can increase the displacement (displacement multiplication), or increase the force (force multiplication). Using newly developed optimization techniques, it is possible to design compliant mechanisms that can achieve multiplication factors of 65X or more.
Application - Voice-Coil Actuator
A compliant displacement amplifier is mated to a linear voice coil actuator. The compliant mechanism can simultaneously provide rectilinear motion guidance while amplifying the force or displacement capability of the actuator. By exploiting low impedance motion amplification, it is possible to obtain large amplitude output motion at frequencies where the voice coil motor cannot directly produce the required motion alone. This device provides 20:1 amplification.
20X Monolithic Motion Amplifier (Voice Coil Actuated)
Application - Piezo Actuator
Mechanical motion amplifiers can be used with any actuation source. Employing these FlexSys amplification devices for use with piezo actuators greatly increases the working envelope of these smart material actuators. A 65X amplifier is shown and each actuator-amplifier weighs 17 grams and occupies a 22.5 mm x 53 mm x 5 mm envelope. The actuator-amplifier provides 4.1 N block force and 2.97 mm free-displacement. The first natural frequency of the system is 300 Hz. The performance capabilities of this actuator far exceed that of competing piezo-amplifier systems and bender-type configurations in terms of block force, stroke, and frequency capability - opening the door to new, compact, high-power actuation systems.
65X Monolithic Motion Amplifier (Piezo Actuated)
