Skip to main content

LUP Student Papers

LUND UNIVERSITY LIBRARIES

Oscillator Based Readout System For Inductively Coupled Stretchable Resistive Strain Sensor

Mårtensson, Billy LU (2023) EITM01 20231
Department of Electrical and Information Technology
Abstract
The development and use of stretchable electronics is a relatively new research field.
However, the use of these kinds of electronics could prove fruitful when seeking to
improve medical sensors and equipment. Since the substrates and manufacturing
methods used when making stretchable electronics allows them to be extremely
thin, with a thickness in the μm range. At these thickness levels, the electronics
are capable of following and adhering to human skin as it bends and stretches.
This project proposes a wireless and stretchable reader and sensor system
which uses a simple oscillator circuit with an inductively coupled resonator to de-
tect resisitve strain in a fully stretchable RLC sensor circuit. By delving into the
malleable... (More)
The development and use of stretchable electronics is a relatively new research field.
However, the use of these kinds of electronics could prove fruitful when seeking to
improve medical sensors and equipment. Since the substrates and manufacturing
methods used when making stretchable electronics allows them to be extremely
thin, with a thickness in the μm range. At these thickness levels, the electronics
are capable of following and adhering to human skin as it bends and stretches.
This project proposes a wireless and stretchable reader and sensor system
which uses a simple oscillator circuit with an inductively coupled resonator to de-
tect resisitve strain in a fully stretchable RLC sensor circuit. By delving into the
malleable nature of these cutting-edge electronics, we determine the most effec-
tive circuit parameters to optimize signal behavior for specific applications. The
findings showed that the simulated frequency shift sensitivity to variations in sen-
sor resistance in a simple NIC based oscillator circuit could (in some cases) be
accurately modelled. The simulation was then confirmed via measurement with a
reader circuit inductively coupled to a stretchable sensor. Further resistive strain
experiments revealed a frequency shift of -0.129% per 1% of strain in the sensor re-
sistor, which was high enough to detect the relatively faint skin deformation caused
by a pulse wave from the heart. The system was then further capable of measur-
ing the heart rate of a person which was verified using a photoplethysmography
sensor. (Less)
Please use this url to cite or link to this publication:
author
Mårtensson, Billy LU
supervisor
organization
course
EITM01 20231
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Sensor, Wireless, Stretchable Electronics
report number
LU/LTH-EIT 2023-949
language
English
id
9137000
date added to LUP
2023-09-19 14:38:56
date last changed
2023-09-19 14:38:56
@misc{9137000,
  abstract     = {{The development and use of stretchable electronics is a relatively new research field.
However, the use of these kinds of electronics could prove fruitful when seeking to
improve medical sensors and equipment. Since the substrates and manufacturing
methods used when making stretchable electronics allows them to be extremely
thin, with a thickness in the μm range. At these thickness levels, the electronics
are capable of following and adhering to human skin as it bends and stretches.
This project proposes a wireless and stretchable reader and sensor system
which uses a simple oscillator circuit with an inductively coupled resonator to de-
tect resisitve strain in a fully stretchable RLC sensor circuit. By delving into the
malleable nature of these cutting-edge electronics, we determine the most effec-
tive circuit parameters to optimize signal behavior for specific applications. The
findings showed that the simulated frequency shift sensitivity to variations in sen-
sor resistance in a simple NIC based oscillator circuit could (in some cases) be
accurately modelled. The simulation was then confirmed via measurement with a
reader circuit inductively coupled to a stretchable sensor. Further resistive strain
experiments revealed a frequency shift of -0.129% per 1% of strain in the sensor re-
sistor, which was high enough to detect the relatively faint skin deformation caused
by a pulse wave from the heart. The system was then further capable of measur-
ing the heart rate of a person which was verified using a photoplethysmography
sensor.}},
  author       = {{Mårtensson, Billy}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Oscillator Based Readout System For Inductively Coupled Stretchable Resistive Strain Sensor}},
  year         = {{2023}},
}