Optimal Piezoelectric Potential Distribution for Controlling Multimode Vibrations

Abstract

Vibration damping is prominent in engineering; in fact, vibrations are related to many phenomena (e.g., the fatigue of structural elements). The advent of smart materials has significantly increased the number of available solutions in this field. Among smart materials, piezoelectric materials are most promising. However, their efficiency depends on their placement. There are many studies on their optimal placement for damping a particular mode, but few account for multimodal vibrations damping. In a previous work, an analytical method was proposed to find the optimal placement of piezoelectric plates to control the multimode vibrations of a cantilever beam. In this study, the efficiency of the above method has been improved, considering all plates active simultaneously, regardless of the eigenmodes that are excited, and changing, instead of the plates, the potential distribution. The method results indicate the optimal potential distribution for different excited eigenmodes. The results have been compared with those obtained by experimental tests and numerical simulations, exhibiting very good agreement.

A Feasibility Study of a Novel Piezo MEMS Tweezer for Soft Materials Characterization

“…Concerning the piezoelectric actions, many studies [63,[80][81][82] have confirmed that, under certain assumptions (piezoelectric plates are perfectly bonded to the structure, the ratio between their thickness and the thickness of the beam is very low and their inertia and mass negligible with respect to those of the beam) the stresses applied to the beam can be considered as they were concentrated at the piezoelectric plate ends. Moreover, if the electric field to the upper plate is opposite in sign to the one applied to the lower plate, such action is equivalent to a flexural moment (see Figure 3) applied to the end of the beam of magnitude equal to: By activating the piezoelectric plates pairs on the two jaws-beams of the tweezer in opposite manner the two moments M a will have opposite sign and the beams will bend in opposite direction allowing the gripper to grasp the soft tissue, as depicted in Figure 4.…”

Using Video Processing for the Full-Field Identification of Backbone Curves in Case of Large Vibrations

“…Indeed, MEMS sensors are generally the default choice for vibrational analysis, and new prototypes are continuously developed [10]. Recently, the use of piezoelectric patches glued to the structure, widely used for vibrational analysis and control [11,12], was also proposed for experimental nonlinear modal analysis [13]; however, patches’ mass, while distributed over a larger surface than in the case of accelerometers, is still not negligible for thin structures. No attempt to use contactless measures of the large deflections’ displacements for NLMA seems to have ever been performed via video recording, while optical methods are starting to be widely used for modal analysis at the current state (e.g., [14,15]).…”

Algorithm for the layout of a piezoelectric element in an elastic medium providing the maximal piezoelectric effect within a specified frequency range

“…• employment of a single piezoelectric element and a complicated branched shunting circuit that enables damping several vibration modes [2][3][4][5][6][7][8][9][10]; • employment of several piezoelectric elements [11][12][13][14][15][16][17][18][19][20].…”

“…Otherwise though, piezoelectric elements are generally not connected to each other and instead each one has its own shunting circuit [16,17]. In this regard, a number of researchers consider an array of piezoelectric elements uniformly distributed across a surface of a structure having the shape of a beam in order to realize multimodal control strategy [18][19][20].…”