Design, Fabrication, Testing and Simulation of a Rotary Double Comb Drives Actuated Microgripper

Abstract

This paper presents the development of a new microgripper actuated by means of rotary-comb drives equipped with two cooperating fingers arrays. The microsystem presents eight CSFH flexures (Conjugate Surface Flexure Hinge) that allow the designer to assign a prescribed motion to the gripping tips. In fact, the adoption of multiple CSFHs gives rise to the possibility of embedding quite a complex mechanical structure and, therefore, increasing the number of design parameters. For the case under study, a double four-bar linkage in a mirroring configuration was adopted. The presented microgripper has been fabricated by using a hard metal mask on a Silicon-on-Insulator (SOI) wafer, subject to DRIE (Deep Reactive Ion Etching) process, with a vapor releasing final stage. Some prototypes have been obtained and then tested in a lab. Finally, the experimental results have been used in order to assess simulation tools that can be used to minimize the amount of expensive equipment in operational environments.

Dynamic Model of a Conjugate-Surface Flexure Hinge Considering Impacts between Cylinders

“…As a consequence, several new devices, obtained by means of micromachining, were proposed in the literature. For example, biosensing acoustic wave based devices [2], CMOS-MEMS resonators [3], microgrippers [4], drug delivery micropumps [5], surgery [6], micromirror platforms [7], and more generally actuators [8,9] and sensors [10].…”

Downsizing Effects on Micro and Nano Comb Drives

“…Since the actuation is a key issue for a micro or nano mechanism to be suitable in operational scenarios [35], this investigation takes an electro-mechanical actuator as a test case to study the influence of the downscaling effects in both complex MEMS and (mainly) NEMS. More specifically, a rotary comb drive has been considered, as they are widely known for versatility, performance and operational simplicity at different scales [36][37][38][39]. Three main aspects of a device development has been investigated: design, simulation and fabrication.…”

Image quality comparison of two different experimental setups for MEMS actuators functional evaluation: a preliminary study

“…Microgrippers (MGs) are devices based on MEMS (Micro Electro-Mechanical System) technology, able to grasp and manipulate objects of microscopic size, suitable for a wide range of applications, especially in the biomedical field and in particular, the manipulation of cells and tissues where they can contribute to the development of minimally invasive surgery techniques and the characterization of biological samples [1][2][3]. In this regard, the present study is part of a research aimed at developing image analysis-based measurement methods and systems for the characterization of electrostatic actuated MGs [4][5][6][7][8][9]. The Device Under Test (DUT) is the MG prototype in Fig.…”

“…The Device Under Test (DUT) is the MG prototype in Fig. 1, fabricated by Deep Reactive Ion Etching (DRIE) process, using an aluminum hard mask on a silicon-oninsulator wafer [4][5]. Previous studies from the Authors [5][6][7][8] focused on measuring the displacement as a function of the supply voltage.…”

“…1, fabricated by Deep Reactive Ion Etching (DRIE) process, using an aluminum hard mask on a silicon-oninsulator wafer [4][5]. Previous studies from the Authors [5][6][7][8] focused on measuring the displacement as a function of the supply voltage. Due to the small displacement values obtained for low supply voltage values and the small size of some parts of the device (e.g., the fingers thickness in the comb-drives is 4 μm only), the optical setup should be able to acquire images whose quality guarantee the measurement of a few microns and therefore the performance of a digital imaging system for this type of analysis in optical microscopy strongly depends also on the camera used for image digitalization.…”