Microfabricated Shear -Sensitive Tactile Sensor: Development and Application
Wang, Lin
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/80755
Description
Title
Microfabricated Shear -Sensitive Tactile Sensor: Development and Application
Author(s)
Wang, Lin
Issue Date
2001
Doctoral Committee Chair(s)
David J. Beebe
Department of Study
Electrical Engineering
Discipline
Electrical Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Engineering, Biomedical
Language
eng
Abstract
This research includes the sensor design, fabrication, modeling, characterization, and application. The sensor design is based on a silicon diaphragm structure instrumented with four piezoresistors. A square mesa on top of the diaphragm is used to convert an applied force into stress. Each of the four resistors is designed as an independent strain gage to allow the sensor to resolve both normal and shear forces. The sensor is fabricated using integrated circuit (IC) and MEMS technologies. KOH etching is used to make the diaphragm. Low-temperature wafer bonding is used to seal the cavities. EPON su-8 is used to construct the mesa. Silicon isotropic etching is used to release PI/Al/PI leads to realize flexible package. An analytical model is developed for describing applied forces, induced stress, the resistance variation, and their relationships. Bench characterization is performed with a 0--3 N force applied at elevation angles of 0°, 30°, 45° and 60°. At each elevation angle, the sensor is rotated from 0° to 360° at increments of 30°. The bench characterization results demonstrate shear-force sensing ability. The characterization of the sensor on human subjects is performed with 5--40 N shear and 0--30 N compressive hand grasping forces applied. The results demonstrate the sensor's capability of measuring forces at human-object interfaces. Finally, the sensor is used to measure the finger forces during cylinder grasping. The normal and shear forces are measured at torque levels of 6.9, 11.5, 16.1, 20.7, and 25.3 kg-cm. for three segments of the middle fingers on six subjects. The results show that both normal and shear forces vary linearly with torque. The shear force is dominant in the cylinder grasping. The distal phalanx played the major role in the turning activity, whereas the middle phalanx played the major role in holding activity.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
