Brandon D. Pereies e-mail: [email protected]
Andrew J. DeRouin e-mail: [email protected]
Keat Ghee Ong 8-maii: i
0.46
B
Coil
en 0.44
es
0.42
0.3
o
Han
§
es O
=0.044 kN R4= 0.067 kN .-•- R4= 0.089 kN .A..R4=o.lllkN • - R 4 =0.133 kN
0.4
0.38
0.36 0.04
•
0.35
0.06
0.08
0.1
0.12
Force (kN) Applied at R3 (b)
1
0.25
0.2
0.1'
-R4 = 0.044 kN -R4 = 0.067 kN • R4 = 0.089 kN •R4 = 0.111 kN -R4 =0.133 kN
0.15 0.04
0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3 (b)
Fig. 5 An increasing sensor response was observed while Fig. 6 A decreasing sensor response was observed while monitoring trom (a) coil 1 and (b) coil 3 with a changing load monitoring from (a) coil 2 and (b) coil 4 with a changing load applied to R1 and R3 and constant loading applied to R2 and R4 applied to R1 and R3 and constant loading applied to R2 and R4 Journal of Biomechanical Engineering
JANUARY2014, Vol. 136 / 011010-3
Figs. 5 and 6 were first curve-fitted with decaying exponential equations. (1) where S is the sensor response, A is the peak amplitude, B is the slope of the curve, C is the y-intercept of the curve,/is the applied force, and ; is the region being loaded. After performing this curve fitting, it was determined that the values of A and B were nearly constant between curve fits, while the value of C was affected from loading on the opposing region of each strip. The dependency of C towards force loading at the opposite region can be described with (2a)
C, = a , ( l -
c,
¡>2
(26)
Coefficient values for A, B, a, b, and c were then determined empirically from curves in Figs. 5 and 6, completing the algorithm. To determine force loading (f,) from the measurements {Si), the algorithm used an iterative process. As an illustration, to determine/i and/2, the algorithm first started with Rl (/ = 1) and set an
initial value for/2 (e-g->/2 = 0) in Eq. (la) to solve for C2. The calculated C2 was then plugged into Eq. (1) to solve for a predicted/2. The calculated/2 was then used in Eq. {2b) to solve for Cl, which was then substituted into Eq. (1) to solve for a new/i. This process was repeated until the calculated values for the expected forces and coefficients satisfied Eqs. (1) and (2) within an acceptable error. Using this method, the algorithm was used to recalculate the raw sensor response with a < l % maximum error (see Figs. l{a)-l{d)). Additionally, the maximum error of calculating the expected forces from sensor data was determined as less than 7% (see Figs. 8(a)-8(t/)). To reduce this en'or in future works, more rigorous calibrations and higher-resolution solving methods will be developed. Additionally, while the sensor illustrated little drift when loaded cyclically, the effects of changing position in relation to the detection coils on sensor response will need to be accounted for, as previous work has demonstrated that position does have an effect on the magnitude of sensor response [11]. To account for this, it is necessary for the sensors and coils to be properly aligned prior to use by adjusting the coils on unloaded sensors until receivhig the expected signals. An alternative technique is to develop a calibration algorithm using another nonloaded sensor strip as a force-independent input parameter. Figure 9 plots the change in measured harmonic amplitude at Rl when Rl was cyclically loaded from 0.044kN to 0.133 kN. The sensor illustrated little drift when loaded cyclically. To
0.42
>
0.4
^
0.38
O
U
0.48
0.36
01
X IN
_,
0.44
0.3
0.28 0.06
0.08
0.1
0.12
0.42
o
R2 = 0.044 kN R2 = 0.067 kN -— R2 = 0.089 kN R2 = 0.HlkN - —R2 = 0.133kN
0.32
0.26 0.04
0.46
"5 U
0.34
o
>
o
0.4
R4 = 0.044 kN R4 = 0.067 kN —- R4 = 0.089 kN R4 = 0.111kN • —R4 = 0.133 kN
••yy
0.38
0.36 0.04
0.14
0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3
Force (kN) Applied at Rl (a)
(b)
0.48 0.46
>
0.4
—
0.35
C8 O
0.3
0.44
o
0.42
o
0.4
ta o o
0.38 0.36 0.34
CM
"5 O
0.32 0.04
1
R2 = 0.044 kN R2 = 0.067 kN -— R2 = 0.089 kN R2 = 0.111kN - —R2 = 0.133kN 0.06
0.08
0.25
0.2
0.1
0.12
Force (kN) Applied at Rl (c)
0.14
0.04
R4 = 0.044 kN R4 = 0.067 kN •— R4 = 0.089 kN R4 = 0.111kN • —R4 = 0.133 kN 0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3 (d)
Fig. 7 The raw sensor data was recalculated using the developed algorithm for testing, where a changing load was applied to R1 and R3 and a constant ioad was heid on R2 and R4 when monitoring from (a) coil 1, (b) coil 3, (c) coil 2, and (d) coil 4
011010-4 / Vol. 136, JANUARY 2014
Transactions of the ASME
0.14
0.14 •"S •
g" 0.12
H-'
0.1 M'
o n O X +
0.08
Ô 0.06 J
0.04 0.04
0.06
0.08
0.08 -
J
0.12
M''
X R4 = 0.111kN + R 4 = 0.133 kN
0.04 0.04
0.14
0.06
Force (kN) Applied at RI (a) FÍ2-o:i33kÑ
— ^
0.12
. . — ^
.
i
"
lculated Force g P
2-0.089 m •
•
s
0.14
t
g 0.12
Fi2-O.lllkN
•
'S 0.08
1
0.12
0.14
:-R4^0;t3J
\
; iR4-O.ÏU;
;
-
y....
1
S 0.1 -o
0.1
...., ?2-0.067 kÑ
H.*
: T
0.08
•-
Force (kN) Applied at R3 (b)
i R4-0.089; i • i
*
CO
0.14
o R4 = 0.044 kN a R4 = 0.067 kN 0 R4 = 0.089 kN
Ö 0.06 0.' -
j
0.1
• '
-a
R2 = 0.044 kN R2= 0.067 kN R2= 0.089 kN R2 = 0.111 kN R2 =0.133 kN
*
\ R4-0.067
: ; i
:
(S
0 0.06
o 0.06 0.04 0.04
i R4-0.044;
R2-0.044 klk
«
.......... ._.......,
0.06
.........J...-..,....,.......,
0.08
0.1
0.12
0 04 0.14
•••""•
0.04
_ . ._ _ i
:*'. '.'
0.06
0.08
_L
i •
L
» .
i":''r':"r""":"r'r"". 0.1
0.12
0.14
Force (kN)
Force (kN) (c)
Fig. 8 The applied ioading was recaicuiated using the developed algorithm for testing, where a changing ioad was appiled to R1 and R3 and a constant ioad was held on R2 and R4 when monitoring from (a) coii 1, (b) coii 3, (c) coii 2, and (d) coii 4
characterize the stability of the sensor when under repetitive and changing loads at both ends of the sensor strip, the response at Rl and R3 was also monitored while force loading was cycled at Rl and R3 from 0.044 kN to 0.133 kN (five measurements were taken
> E
at each force loading) while force loading at R2 and R4 was held constant. Force loading at R2 and R4 was then increased at an interval of 0.022 kN after completion of each cycle at Rl and R3. Figure 10 illustrates that the sensor response showed symmetric "stepped pyramids," indicating low hysteresis and drift. There is also a consistent decrease in amplitude for each stepped pyramid, indicating that increased loading at R2 and R4 decreased the sensor signal when measured at Rl and R3. This is consistent with observations in Fig. 5.
o
Conclusion
0.35 -I
0.3
10
15
20
25
30
35
40
Test Number Fig. 9 Cyciic ioading of the sensor was performed from 0.044 kN to 0.133kN over the course of ten ioading cycies with results iiiustrating low drift in sensor response Journal of Biomechanical Engineering
A wireless, passive sensor system capable of mapping the force on biomédical devices was developed. The proposed system was constructed with custom rectangular magnetoelastic sensing strips capable of measuring applied forces on two quadrants of a single strip simultaneously. In order to illustrate the ease with which the sensor system can be deployed, the sensor was adhered to the lower portion of a prosthetic. These advances are important due to the lack of wireless, longterm monitoring systems available to medical staff to diagnose force-related device malfunctions and failures. Overall, this device could drastically improve the quality of care for patients with an implantable device and assist in the further development of better implants and devices, such as prosthetics, by contributing JANUARY2014, Vol. 136 / 011010-5
0.42 0.4
0.38 0.36 0.34
Socket'
0.32 0.3 Í
0.28 100
200
300
400
Test Number (a)
Detection coils ElectronicsShank. Fig. 11 Illustration of the implementation of the stress/forcemonitoring system. To wireiessly monitor responses of the sensors, the system will feature attached electronics, including a power supply, excitation circuitry, and transceiver for wireless data transmission. The excitation/detection coils will be attached to the prosthetic, with the sensing strips sandwiched in between the coupler that connects the shank to the socket.
0.36 0
100
200
300
400
Test Number (b) Fig. 10 Stability testing of the sensor while applying a changing load from 0.044 kN to 0.133kN at (a) R1 and (d) R3 with constant loads, changed at 0.022 kN intervals between load cycles, held on R2 and R4. The sensor responses were monitored from coil 1 and coil 3 and illustrated stepped pyramid responses with low hysteresis and drift.
to the understanding of the dynamic loads that biomédical devices experience. Future works will focus on developments toward full in vivo testing, as illustrated in Fig. 11. Specifically, a process for fabricating more consistent sensor arrays, as opposed to the current shearing method, along with electronics capable of being attached to existing prosthetics will be pursued. Additionally, while the presented algorithm is fully functional, improvements will be necessary when the array is expanded to include more strips. Moreover, the current detection system connects directly to a personal computer (PC) for data processing and storage, and in the future, portable battery units, memory storage, and wireless data transmission to the PC will be incorporated into the system to develop a truly portable sensing platform.
Acknowledgment The authors would like to acknowledge Northem Orthotics & Prosthetics Inc. for their contributions to this work. This research was conducted in part with support under and awarded by Department of Defense, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168 a, and the Department of Defense of the Office of the 011010-6 / Vol. 136, JANUARY 2014
Congressionally Directed Medical Research Programs, Grant DR081026 Hypothesis Development.
Nomenclature A = peak amplitude B = slope of the curve C = y-intercept of curve / = applied force Í = region being loaded S = sensor response
References [1] Mak, A. F., Zhang, M., and Tam, E. W. C , 2010, "Biomechanics of Pressure Ulcer in Body Tissues Interacting With External Forces During Locomotion," Annu. Rev. Biomed. Eng., 12(1). pp. 29-53. [2] Gailey, R., Allen, K., Castles, J., Kucharik, K., and Roeder, M., 2008, "Review of Secondary Physical Conditions Associated With Lower-Limb Amputation and Long-Term Prosthesis Use," J. Rehabil. Res. Dev., 45(1), pp. 15-29. (3] Salawu, C , Middleton, A., Gilbertson, A., Kodavali, K., and Neumann. V., 2006, "Stump Ulcers and Continued Prosthetic Limb Use," Prosthet. Orthot. lnt.,30(3), pp. 279-285. ]4] Mak. A. F.. Zhang, M., and Boone. D. A., 2001, "State-Of-The-Art Research in Lower-Limb Prosthetic Biomechanics-Socket Interface: A Review," J. Rehabil. Res. Dev., 38(2), pp. 161-174. ]5] Polliack, A. A., Craig, D. D., Sieh, R. C , Landsberger, S., and McNeal, D. R., 2002. "Laboratory and Clinical Tests of a Prototype Pressure Sensor for Clinical Assessment of Prosthetic Socket Fit," Prosthet. Orthot. Int., 26(1), pp. 23-34. [6] Baars. E. C. T., and Geertzen, J. H. B., 2005, "Literature Review of the Possible Advantages of Silicon Liner Socket Use in Trans-Tibial Prostheses," Prosthet. Orthot. Int.. 29(1), pp. 27-37. [7] Meulenbelt, H. E. J., Dijkstra, P. U., Jonkman, M. F., and Geertzen, J. H. B., 2006, "Skin Problems in Lower Limb Amputees: A Systematic Review," Disabil. Rehabil., 28(10), pp. 603-608. [8] Ogawa, G., Obinata, K., Hase, K., Dutta, A., and Nakagawa, M., 2008, "Design of Lower Limb Prosthesis With Contact Pressure
Transactions of the ASME
Adjustment by MR Fluid." Conf. Proc. IEEE Eng. Med. Bid. Soc. 2008. pp. 330-333. ig] Frossard. L.. Beck, J., Dillon, M., and Evans, J., 2003. "Development and Preliminary Testing of a Device for the Direct Measurement of Forces and Moments in the Prosthetic Limb of Transfemoral Amputees During Activities of Daily Living," J. Prosthet. Orthot.. 15(4). pp. 135-142.
Journal of Biomechanical Engineering
[10] Sundara-Rajati, K., Bestick. A., Rowe. G. I.. Klute, G. K., Ledoux. W. R., Wang, H. C . and Mamishev, A. V., 2012, "An Intetfacial Stress Sensor for Biomechanical Applications." Meas. Sei. Techtiol., 23(8). p. 085701. [11] Pereles, B. D., DeRouin, A. J., Dienhart, T. A.. Tan. E. L., and Ong. K. G.. 2012. "A Wireless. Magnetoelastic-Based Sensor Array for Force Monitoring on a Hard Surface," Sens. Lett.. 10(3-4). pp. 806-813.
JANUARY 2014, Vol. 136 / 011010-7
Copyright of Journal of Biomechanical Engineering is the property of American Society of Mechanical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Andrew J. DeRouin e-mail: [email protected]
Keat Ghee Ong 8-maii: i
0.46
B
Coil
en 0.44
es
0.42
0.3
o
Han
§
es O
=0.044 kN R4= 0.067 kN .-•- R4= 0.089 kN .A..R4=o.lllkN • - R 4 =0.133 kN
0.4
0.38
0.36 0.04
•
0.35
0.06
0.08
0.1
0.12
Force (kN) Applied at R3 (b)
1
0.25
0.2
0.1'
-R4 = 0.044 kN -R4 = 0.067 kN • R4 = 0.089 kN •R4 = 0.111 kN -R4 =0.133 kN
0.15 0.04
0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3 (b)
Fig. 5 An increasing sensor response was observed while Fig. 6 A decreasing sensor response was observed while monitoring trom (a) coil 1 and (b) coil 3 with a changing load monitoring from (a) coil 2 and (b) coil 4 with a changing load applied to R1 and R3 and constant loading applied to R2 and R4 applied to R1 and R3 and constant loading applied to R2 and R4 Journal of Biomechanical Engineering
JANUARY2014, Vol. 136 / 011010-3
Figs. 5 and 6 were first curve-fitted with decaying exponential equations. (1) where S is the sensor response, A is the peak amplitude, B is the slope of the curve, C is the y-intercept of the curve,/is the applied force, and ; is the region being loaded. After performing this curve fitting, it was determined that the values of A and B were nearly constant between curve fits, while the value of C was affected from loading on the opposing region of each strip. The dependency of C towards force loading at the opposite region can be described with (2a)
C, = a , ( l -
c,
¡>2
(26)
Coefficient values for A, B, a, b, and c were then determined empirically from curves in Figs. 5 and 6, completing the algorithm. To determine force loading (f,) from the measurements {Si), the algorithm used an iterative process. As an illustration, to determine/i and/2, the algorithm first started with Rl (/ = 1) and set an
initial value for/2 (e-g->/2 = 0) in Eq. (la) to solve for C2. The calculated C2 was then plugged into Eq. (1) to solve for a predicted/2. The calculated/2 was then used in Eq. {2b) to solve for Cl, which was then substituted into Eq. (1) to solve for a new/i. This process was repeated until the calculated values for the expected forces and coefficients satisfied Eqs. (1) and (2) within an acceptable error. Using this method, the algorithm was used to recalculate the raw sensor response with a < l % maximum error (see Figs. l{a)-l{d)). Additionally, the maximum error of calculating the expected forces from sensor data was determined as less than 7% (see Figs. 8(a)-8(t/)). To reduce this en'or in future works, more rigorous calibrations and higher-resolution solving methods will be developed. Additionally, while the sensor illustrated little drift when loaded cyclically, the effects of changing position in relation to the detection coils on sensor response will need to be accounted for, as previous work has demonstrated that position does have an effect on the magnitude of sensor response [11]. To account for this, it is necessary for the sensors and coils to be properly aligned prior to use by adjusting the coils on unloaded sensors until receivhig the expected signals. An alternative technique is to develop a calibration algorithm using another nonloaded sensor strip as a force-independent input parameter. Figure 9 plots the change in measured harmonic amplitude at Rl when Rl was cyclically loaded from 0.044kN to 0.133 kN. The sensor illustrated little drift when loaded cyclically. To
0.42
>
0.4
^
0.38
O
U
0.48
0.36
01
X IN
_,
0.44
0.3
0.28 0.06
0.08
0.1
0.12
0.42
o
R2 = 0.044 kN R2 = 0.067 kN -— R2 = 0.089 kN R2 = 0.HlkN - —R2 = 0.133kN
0.32
0.26 0.04
0.46
"5 U
0.34
o
>
o
0.4
R4 = 0.044 kN R4 = 0.067 kN —- R4 = 0.089 kN R4 = 0.111kN • —R4 = 0.133 kN
••yy
0.38
0.36 0.04
0.14
0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3
Force (kN) Applied at Rl (a)
(b)
0.48 0.46
>
0.4
—
0.35
C8 O
0.3
0.44
o
0.42
o
0.4
ta o o
0.38 0.36 0.34
CM
"5 O
0.32 0.04
1
R2 = 0.044 kN R2 = 0.067 kN -— R2 = 0.089 kN R2 = 0.111kN - —R2 = 0.133kN 0.06
0.08
0.25
0.2
0.1
0.12
Force (kN) Applied at Rl (c)
0.14
0.04
R4 = 0.044 kN R4 = 0.067 kN •— R4 = 0.089 kN R4 = 0.111kN • —R4 = 0.133 kN 0.06
0.08
0.1
0.12
0.14
Force (kN) Applied at R3 (d)
Fig. 7 The raw sensor data was recalculated using the developed algorithm for testing, where a changing load was applied to R1 and R3 and a constant ioad was heid on R2 and R4 when monitoring from (a) coil 1, (b) coil 3, (c) coil 2, and (d) coil 4
011010-4 / Vol. 136, JANUARY 2014
Transactions of the ASME
0.14
0.14 •"S •
g" 0.12
H-'
0.1 M'
o n O X +
0.08
Ô 0.06 J
0.04 0.04
0.06
0.08
0.08 -
J
0.12
M''
X R4 = 0.111kN + R 4 = 0.133 kN
0.04 0.04
0.14
0.06
Force (kN) Applied at RI (a) FÍ2-o:i33kÑ
— ^
0.12
. . — ^
.
i
"
lculated Force g P
2-0.089 m •
•
s
0.14
t
g 0.12
Fi2-O.lllkN
•
'S 0.08
1
0.12
0.14
:-R4^0;t3J
\
; iR4-O.ÏU;
;
-
y....
1
S 0.1 -o
0.1
...., ?2-0.067 kÑ
H.*
: T
0.08
•-
Force (kN) Applied at R3 (b)
i R4-0.089; i • i
*
CO
0.14
o R4 = 0.044 kN a R4 = 0.067 kN 0 R4 = 0.089 kN
Ö 0.06 0.' -
j
0.1
• '
-a
R2 = 0.044 kN R2= 0.067 kN R2= 0.089 kN R2 = 0.111 kN R2 =0.133 kN
*
\ R4-0.067
: ; i
:
(S
0 0.06
o 0.06 0.04 0.04
i R4-0.044;
R2-0.044 klk
«
.......... ._.......,
0.06
.........J...-..,....,.......,
0.08
0.1
0.12
0 04 0.14
•••""•
0.04
_ . ._ _ i
:*'. '.'
0.06
0.08
_L
i •
L
» .
i":''r':"r""":"r'r"". 0.1
0.12
0.14
Force (kN)
Force (kN) (c)
Fig. 8 The applied ioading was recaicuiated using the developed algorithm for testing, where a changing ioad was appiled to R1 and R3 and a constant ioad was held on R2 and R4 when monitoring from (a) coii 1, (b) coii 3, (c) coii 2, and (d) coii 4
characterize the stability of the sensor when under repetitive and changing loads at both ends of the sensor strip, the response at Rl and R3 was also monitored while force loading was cycled at Rl and R3 from 0.044 kN to 0.133 kN (five measurements were taken
> E
at each force loading) while force loading at R2 and R4 was held constant. Force loading at R2 and R4 was then increased at an interval of 0.022 kN after completion of each cycle at Rl and R3. Figure 10 illustrates that the sensor response showed symmetric "stepped pyramids," indicating low hysteresis and drift. There is also a consistent decrease in amplitude for each stepped pyramid, indicating that increased loading at R2 and R4 decreased the sensor signal when measured at Rl and R3. This is consistent with observations in Fig. 5.
o
Conclusion
0.35 -I
0.3
10
15
20
25
30
35
40
Test Number Fig. 9 Cyciic ioading of the sensor was performed from 0.044 kN to 0.133kN over the course of ten ioading cycies with results iiiustrating low drift in sensor response Journal of Biomechanical Engineering
A wireless, passive sensor system capable of mapping the force on biomédical devices was developed. The proposed system was constructed with custom rectangular magnetoelastic sensing strips capable of measuring applied forces on two quadrants of a single strip simultaneously. In order to illustrate the ease with which the sensor system can be deployed, the sensor was adhered to the lower portion of a prosthetic. These advances are important due to the lack of wireless, longterm monitoring systems available to medical staff to diagnose force-related device malfunctions and failures. Overall, this device could drastically improve the quality of care for patients with an implantable device and assist in the further development of better implants and devices, such as prosthetics, by contributing JANUARY2014, Vol. 136 / 011010-5
0.42 0.4
0.38 0.36 0.34
Socket'
0.32 0.3 Í
0.28 100
200
300
400
Test Number (a)
Detection coils ElectronicsShank. Fig. 11 Illustration of the implementation of the stress/forcemonitoring system. To wireiessly monitor responses of the sensors, the system will feature attached electronics, including a power supply, excitation circuitry, and transceiver for wireless data transmission. The excitation/detection coils will be attached to the prosthetic, with the sensing strips sandwiched in between the coupler that connects the shank to the socket.
0.36 0
100
200
300
400
Test Number (b) Fig. 10 Stability testing of the sensor while applying a changing load from 0.044 kN to 0.133kN at (a) R1 and (d) R3 with constant loads, changed at 0.022 kN intervals between load cycles, held on R2 and R4. The sensor responses were monitored from coil 1 and coil 3 and illustrated stepped pyramid responses with low hysteresis and drift.
to the understanding of the dynamic loads that biomédical devices experience. Future works will focus on developments toward full in vivo testing, as illustrated in Fig. 11. Specifically, a process for fabricating more consistent sensor arrays, as opposed to the current shearing method, along with electronics capable of being attached to existing prosthetics will be pursued. Additionally, while the presented algorithm is fully functional, improvements will be necessary when the array is expanded to include more strips. Moreover, the current detection system connects directly to a personal computer (PC) for data processing and storage, and in the future, portable battery units, memory storage, and wireless data transmission to the PC will be incorporated into the system to develop a truly portable sensing platform.
Acknowledgment The authors would like to acknowledge Northem Orthotics & Prosthetics Inc. for their contributions to this work. This research was conducted in part with support under and awarded by Department of Defense, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168 a, and the Department of Defense of the Office of the 011010-6 / Vol. 136, JANUARY 2014
Congressionally Directed Medical Research Programs, Grant DR081026 Hypothesis Development.
Nomenclature A = peak amplitude B = slope of the curve C = y-intercept of curve / = applied force Í = region being loaded S = sensor response
References [1] Mak, A. F., Zhang, M., and Tam, E. W. C , 2010, "Biomechanics of Pressure Ulcer in Body Tissues Interacting With External Forces During Locomotion," Annu. Rev. Biomed. Eng., 12(1). pp. 29-53. [2] Gailey, R., Allen, K., Castles, J., Kucharik, K., and Roeder, M., 2008, "Review of Secondary Physical Conditions Associated With Lower-Limb Amputation and Long-Term Prosthesis Use," J. Rehabil. Res. Dev., 45(1), pp. 15-29. (3] Salawu, C , Middleton, A., Gilbertson, A., Kodavali, K., and Neumann. V., 2006, "Stump Ulcers and Continued Prosthetic Limb Use," Prosthet. Orthot. lnt.,30(3), pp. 279-285. ]4] Mak. A. F.. Zhang, M., and Boone. D. A., 2001, "State-Of-The-Art Research in Lower-Limb Prosthetic Biomechanics-Socket Interface: A Review," J. Rehabil. Res. Dev., 38(2), pp. 161-174. ]5] Polliack, A. A., Craig, D. D., Sieh, R. C , Landsberger, S., and McNeal, D. R., 2002. "Laboratory and Clinical Tests of a Prototype Pressure Sensor for Clinical Assessment of Prosthetic Socket Fit," Prosthet. Orthot. Int., 26(1), pp. 23-34. [6] Baars. E. C. T., and Geertzen, J. H. B., 2005, "Literature Review of the Possible Advantages of Silicon Liner Socket Use in Trans-Tibial Prostheses," Prosthet. Orthot. Int.. 29(1), pp. 27-37. [7] Meulenbelt, H. E. J., Dijkstra, P. U., Jonkman, M. F., and Geertzen, J. H. B., 2006, "Skin Problems in Lower Limb Amputees: A Systematic Review," Disabil. Rehabil., 28(10), pp. 603-608. [8] Ogawa, G., Obinata, K., Hase, K., Dutta, A., and Nakagawa, M., 2008, "Design of Lower Limb Prosthesis With Contact Pressure
Transactions of the ASME
Adjustment by MR Fluid." Conf. Proc. IEEE Eng. Med. Bid. Soc. 2008. pp. 330-333. ig] Frossard. L.. Beck, J., Dillon, M., and Evans, J., 2003. "Development and Preliminary Testing of a Device for the Direct Measurement of Forces and Moments in the Prosthetic Limb of Transfemoral Amputees During Activities of Daily Living," J. Prosthet. Orthot.. 15(4). pp. 135-142.
Journal of Biomechanical Engineering
[10] Sundara-Rajati, K., Bestick. A., Rowe. G. I.. Klute, G. K., Ledoux. W. R., Wang, H. C . and Mamishev, A. V., 2012, "An Intetfacial Stress Sensor for Biomechanical Applications." Meas. Sei. Techtiol., 23(8). p. 085701. [11] Pereles, B. D., DeRouin, A. J., Dienhart, T. A.. Tan. E. L., and Ong. K. G.. 2012. "A Wireless. Magnetoelastic-Based Sensor Array for Force Monitoring on a Hard Surface," Sens. Lett.. 10(3-4). pp. 806-813.
JANUARY 2014, Vol. 136 / 011010-7
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