Microscale Specificities

MATEC Web of Conferences

et al. 2015

Abstract. This paper presents a modeling for a 3DoF electrothermal actuated micro-electro-mechanical (MEMS) mirror used to achieve scanning for optical coherence tomography (OCT) imaging. The device is integrated into an OCT endoscopic probe, it is desired that the optical scanner have small footprint for minimum invasiveness, large and flat optical aperture for large scanning range, low driving voltage and low power consumption for safety reason. With a footprint of 2mm×2mm, the MEMS scanner which is also called as Tip-Tilt-Piston micromirror, can perform two rotations around x and y-axis and a vertical translation along z-axis. This work develops a complete model and experimental characterization. The modeling is divided into two parts: multiphysics characterization of the actuators and parallel kinematics studies of the overall system. With proper experimental procedures, we are able to validate the model via Visual Servoing Platform (ViSP). The results give a detailed overview on the performance of the mirror platform while varying the applied voltage at a stable working frequency. The paper also presents a discussion on the MEMS control system based on several scanning trajectories.

Section: Introductionmentioning

confidence: 99%

Multiphysics & Parallel Kinematics Modeling of a 3DOF MEMS Mirror

Mamat

Rabenorosoa

MATEC Web of Conferences

et al. 2015

“…Integrating force sensors in microsystems improves and facilitates the tasks by providing a force feedback which enables the force control of the system [7,8]. The force measurement at the microscale needs not only to integrate the sensors on or inside the system itself but also to perform measurement closest to the area of interest [9]. This avoids measuring what is happening outside the system itself, reduces the parameter variations of the system and reduces the noise, which are predominant factors at the microscale [10].…”

Section: Introductionmentioning

confidence: 99%

Prototyping of a highly performant and integrated piezoresistive force sensor for microscale applications

Komati

Agnus

J. Micromech. Microeng.

et al. 2014

In this paper, the prototyping of a new piezoresistive microforce sensor is presented. An original design taking advantage on both mechanical and bulk piezoresistive properties of silicon is presented and enables to easily fabricate a very small, large range, high sensitivity with high integration potential sensor. The sensor is made of two silicon strain gages for which widespread and known microfabrication processes are used. The strain gages present a high gage factor which allow a good sensitivity of this force sensor. The dimensions of this sensor are 700µm in length, 100µm in width and 12µm in thickness. These dimensions make its use convenient with many microscale applications notably its integration in a microgripper. The fabricated sensor is calibrated using an industrial force sensor. The design, microfabrication process, and performances of the fabricated piezoresistive force sensor are innovative thanks to its resolution of 100nN and its measurement range of 2mN. This force sensor presents also a high signal to noise ratio, typically 50dB when a 2mN force is applied at the tip of the force sensor.

Sliding Mode Impedance Controlled Smart Fingered Microgripper for Automated Grasp and Release Tasks at the Microscale

Komati

Precision Assembly in the Digital Age

Lutz

2018

Self Cite

The grasp and release of objects have been widely studied in robotics. At the microscale, this problem becomes more difficult due to the microscale specificities which are notably manifested by the high dynamics of microsystems, their small inertia, their fragility, the predominance of surface forces and the high complexity of integrating adapted sensors.In this paper, the problem of the grasp/release task is considered at the microscale. A new nonlinear controller design based on Sliding Mode Impedance Control (SMIC) is proposed to automate the grasp/release of the micropart. The proposed controller controls dexterously the dynamic interaction between the microgripper and the micropart and forces the system to follow the desired dynamic relation (impedance). To perform the grasp/release task, a new smart-fingeredmicrogripper is designed. The microgripper is composed of an active finger with integrated force sensor and a passive finger.The grasp/release of a micropart of size 50 µm×350µm×2mm is tested in experiments using the control scheme and the developed microgripper. The microgripper design and the control scheme tested show their effectiveness for the grasp/release at the microscale.