Synthesis and Control of Piezoelectric Resonant Actuation Systems with Buckling-Beam Motion Amplifier

AIAA Journal ◽  
2008 ◽  
Vol 46 (3) ◽  
pp. 787-791 ◽  
Author(s):  
Jun-Sik Kim ◽  
K. W. Wang ◽  
E. C. Smith
Keyword(s):  
Buckling Beam ◽  
Motion Amplifier ◽  
Beam Motion ◽  
Actuation Systems ◽  
And Control

A Novel Motion Amplifier Using an Axially Driven Buckling Beam

Aerospace ◽  
2003 ◽  
Author(s):  
Jie Jiang ◽  
Eric M. Mockensturm
Keyword(s):  
Small Displacement ◽  
Compliant Structure ◽  
Euler’S Elastica ◽  
Large Rotations ◽  
Elastica Theory ◽  
End Conditions ◽  
Buckling Beam ◽  
Motion Amplifier ◽  
Piezoelectric Stacks ◽  
Measuring Instrumentation

For active materials such as piezoelectric stacks, which produce large force and small displacement, motion amplification mechanisms are often necessary—not simply to trade force for displacement, but to increase the output work transferred through a compliant structure. Here, a new concept for obtaining large rotations from small linear displacements produced by a piezoelectric stack is proposed and analyzed. The concept uses elastic (buckling) and dynamic instabilities of an axially driven buckling beam. The optimal design of the buckling beam end conditions was determined from a static analysis of the system using Euler’s elastica theory. This analysis was verified experimentally. A stack-driven, buckling beam prototype actuator consisting of a pre-compressed PZT stack (140 mm long, 10 mm diameter) and a thin steel beam (60 mm × 12 mm × 0.508 mm) was constructed. The buckling beam served as the motion amplifier, while the PZT stack provided the actuation. The experimental setup, measuring instrumentation and method, the beam preloading condition, and the excitation are fully described in the paper. Frequency responses of the system for three preloading levels and three stack driving amplitudes were obtained. A maximum 16° peak-to-peak rotation was measured when the stack was driven at an amplitude of 325 V and frequency of 39 Hz. The effects of beam preload were also studied.

Energy and Control Characteristics of a Novel Meter Out Hydraulic System for Mobile Applications

2017 ◽  
Author(s):  
Pietro Marani ◽  
Massimo Martelli
Keyword(s):  
Test Procedure ◽  
Distributed Parameter ◽  
The Novel ◽  
Proportional Control ◽  
Virtual Test ◽  
Sensing System ◽  
Automatic Activation ◽  
Control Technologies ◽  
Actuation Systems ◽  
And Control

The metering out sensing system represents the latest, and most promising, architectural concept for improving the performance of mobile multiple actuation systems through hydraulic proportional components control. The first part of the paper introduces the novel architecture of meter-out sensing control system, properly designed to distribute the flow rate directed to actuators according to the proportional control of the metering out element only. To do this, an innovative piloting subsystem controls the pump displacement, while a set of compensated proportional control valves applied to actuators outlet work to manage the load unbalance. The inlet doesn’t have any proportional throttle element thus reducing control losses with respect to state-of-the-art systems. In this way, the architecture is able to control both resisting and overrunning loads, and its design could easily include the automatic activation of the regenerative function to limit the requested hydraulic power. Then, the paper highlights how the proposed architecture of meter-out sensing system, which does not require complex sensor networks or complex electronic controls, could overcome the most important limitations affecting other control technologies currently adopted in mobile hydraulics. The third part of the paper depicts the main results obtained in the evaluation of the performance figures of merit for the metering out sensing system, performed through a Virtual Test Procedure applied to a lumped and distributed parameter numerical model.

Soft Photochemical Actuation Systems: Tuning Performance Through Solvent Selection

2017 ◽  
Author(s):  
Michael P. M. Dicker ◽  
Anna B. Baker ◽  
Ian P. Bond ◽  
Charl F. J. Faul ◽  
Jonathan M. Rossiter ◽  
...  
Keyword(s):  
Lessons Learned ◽  
Cycle Life ◽  
Activation Time ◽  
Power And Control ◽  
Great Hope ◽  
Relative Activation ◽  
Smart Machines ◽  
Actuation Systems ◽  
And Control ◽  
Selection Of

Photochemical actuation systems, those that employ coupled photo-stimuli and chemical reactions to power and control mechanical motion, have the potential to combine the benefits of precise light driven control with chemical energy storage. Furthermore, these systems are inherently soft, making them ideal for use in the emerging field of soft robotics. However, such systems have received comparatively little attention, perhaps due to the poor cycle life and limited activation time of past systems. Here we address these two challenges by switching from the technique of past systems, that of aqueous photoacid solutions and pH-responsive hydrogel actuators, to one employing organic solvents instead. While this switch of solvents successfully eliminates cycle life constraints and allows for tuning of the activation recovery time it also shifts the relative activation point of the hydrogel actuator in such a way that actuation is no longer observed. Several options for addressing this are discussed, with the prospect of using the lessons learned within to make a more informed selection of a different photoacid compound considered the most feasible. While the exploration of photochemical actuation systems is still in a nascent stage, we have great hope for such systems to form the basis of future smart machines with unique functionality.

A Motion Amplifier Using an Axially Driven Buckling Beam: I. Design and Experiments

2006 ◽  
Vol 43 (4) ◽  
pp. 391-409 ◽  
Author(s):  
Jie Jiang ◽  
Eric Mockensturm
Keyword(s):  
Buckling Beam ◽  
Motion Amplifier

Modeling and control of a torque load system with servo actuator's dynamics

2016 ◽  
Vol 231 (9) ◽  
pp. 1676-1685 ◽  
Author(s):  
Xin Wang
Keyword(s):  
Control Method ◽  
Dynamic Performance ◽  
Torque Control ◽  
Control Surface ◽  
Phase Lag ◽  
Load Torque ◽  
Modeling And Control ◽  
Torque Load ◽  
Actuation Systems ◽  
And Control

In this work, the models and control strategy of the Electric Servo-torque System(ESS) which is used as an experiment rig for conducting dynamic performance and stability tests of aerial vehicle control surface actuation systems are presented. The detailed dynamics of the load motor and loaded flight actuator’s rotating movement in the ESS are analyzed, leading to an integrated load torque synchronization system. The kinematic dynamics of the loaded control surface driving actuator is an important consideration to estimate the trend of torque variation and to improve the performance of the load system. The load control method is expressed in terms of a multi-loop torque control law, which uses feedback and feedforward loops to meet system design requirements. Numerical examples together with experimental results are included to illustrate the effectiveness of the proposed models and control parameters. This brief addressed a specific utilization of the loaded actuator’s dynamics, revealing that it can reduce both the phase lag and the amplitude gain of the load torque in the Electric Servo-torque System.

Rate regulation of a suborbital reentry payload by moving-mass actuators

2012 ◽  
Vol 227 (1) ◽  
pp. 80-92 ◽  
Author(s):  
Aidin Mohammadi ◽  
Morteza Tayefi ◽  
Hamed Kashani
Keyword(s):  
Linear Time ◽  
Moving Mass ◽  
Mass System ◽  
Rate Regulation ◽  
Stability And Control ◽  
Aerospace Applications ◽  
Critical Issues ◽  
Significant Performance ◽  
Actuation Systems ◽  
And Control

In order to save cost and time, sounding rockets are effectively used to develop space technologies. In a biological payload that is under the study on this investigation, reentry rate regulation is one of the critical issues to be solved. Because of non-linear time-varying dynamics of these payloads and presence of high aerodynamic disturbances during reentry, choosing an appropriate stability and control mechanism can be an engineering challenge. Having a lot of benefits, nowadays, moving-mass actuation systems are used in a variety of aerospace applications. As an innovative approach, a moving-mass system is designed and analysed to regulate the payload body rates during reentry phase. Simulation results indicate significant performance of suggested application for moving-mass control systems.

Sign in / Sign up

Export Citation Format

Share Document