Understanding frequency response of a flexural complaint stage for use in oscillatory orthogonal cutting

Ultramicrotomy is the process of cutting specimens into submicron-thickness slices for subsequent imaging using a scanning electron microscope (SEM). Ultramicrotomes, devices that employ this process, have incorporated oscillations into this process to reduce the damage done on each slice. Extensive research has been made in trying to identify the appropriate settings: frequency, amplitude of cut, and feed speed, to maximize the reduction of this damage. Currently, however, there exists no research that tries to understand why the introduction of oscillations provides such a reduction in damage. To understand the mechanics behind oscillatory orthogonal cutting, specifically in ultramicrotomy, the frequency response of a compliant mechanism must be understood. The frequency response of a complaint flexural stage driven by piezoelectric actuator was measured. Using a Linear Variable Differential Transformer (LVDT) and a dynamic signal analyzer via LabView, the frequency response of the stage was measured from 100Hz to 10000Hz. A model was then fitted to the measured response. Using this model, a comparison between a simulated-reference response of the position of the stage to the output response of the model showed that a controller was required to minimize the error in the position of the stage.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2015

Author dc:creator

• Barraza, Raul

Advisor dc:contributor.advisor

• Martin L. Culpepper.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/98952

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/98952