Limits...
Detection of Prosthetic Knee Movement Phases via In-Socket Sensors: A Feasibility Study.

El-Sayed AM, Hamzaid NA, Tan KY, Abu Osman NA - ScientificWorldJournal (2015)

Bottom Line: In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand.FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states.In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia ; Mechatronics Section, Mechanical Engineering Department, Faculty of Engineering, Assiut University, Assiut 71516, Egypt.

ABSTRACT
This paper presents an approach of identifying prosthetic knee movements through pattern recognition of mechanical responses at the internal socket's wall. A quadrilateral double socket was custom made and instrumented with two force sensing resistors (FSR) attached to specific anterior and posterior sites of the socket's wall. A second setup was established by attaching three piezoelectric sensors at the anterior distal, anterior proximal, and posterior sites. Gait cycle and locomotion movements such as stair ascent and sit to stand were adopted to characterize the validity of the technique. FSR and piezoelectric outputs were measured with reference to the knee angle during each phase. Piezoelectric sensors could identify the movement of midswing and terminal swing, pre-full standing, pull-up at gait, sit to stand, and stair ascent. In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand. FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states. The study highlighted the capacity of using in-socket sensors for knee movement identification. In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types.

No MeSH data available.


(a) Basic dimensions, extensive parameters, polarization, and applied electric field acting on the bimorph generator [16]. (b) Dimensions of the used bimorph with two fixed ends.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4402191&req=5

fig2: (a) Basic dimensions, extensive parameters, polarization, and applied electric field acting on the bimorph generator [16]. (b) Dimensions of the used bimorph with two fixed ends.

Mentions: The adopted sensors (FSR and piezoelectric) in the current study were placed inside the socket wall (Figure 1). FSR was chosen based on its small size (1.25 mm thickness and 12.7 mm diameter) that will not affect the user comfort. Similarly the piezoelectric sensor has a configuration (Figure 2) as well as dynamic characteristics that make it suitable for such applications [16]. The sensors were tethered to transmit the data directly to the PC via wires. The minimal thickness did not affect the user's natural movements. These sensors were able to accurately characterize the knee movements during walking, stair climbing, and sit to stand.


Detection of Prosthetic Knee Movement Phases via In-Socket Sensors: A Feasibility Study.

El-Sayed AM, Hamzaid NA, Tan KY, Abu Osman NA - ScientificWorldJournal (2015)

(a) Basic dimensions, extensive parameters, polarization, and applied electric field acting on the bimorph generator [16]. (b) Dimensions of the used bimorph with two fixed ends.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4402191&req=5

fig2: (a) Basic dimensions, extensive parameters, polarization, and applied electric field acting on the bimorph generator [16]. (b) Dimensions of the used bimorph with two fixed ends.
Mentions: The adopted sensors (FSR and piezoelectric) in the current study were placed inside the socket wall (Figure 1). FSR was chosen based on its small size (1.25 mm thickness and 12.7 mm diameter) that will not affect the user comfort. Similarly the piezoelectric sensor has a configuration (Figure 2) as well as dynamic characteristics that make it suitable for such applications [16]. The sensors were tethered to transmit the data directly to the PC via wires. The minimal thickness did not affect the user's natural movements. These sensors were able to accurately characterize the knee movements during walking, stair climbing, and sit to stand.

Bottom Line: In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand.FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states.In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia ; Mechatronics Section, Mechanical Engineering Department, Faculty of Engineering, Assiut University, Assiut 71516, Egypt.

ABSTRACT
This paper presents an approach of identifying prosthetic knee movements through pattern recognition of mechanical responses at the internal socket's wall. A quadrilateral double socket was custom made and instrumented with two force sensing resistors (FSR) attached to specific anterior and posterior sites of the socket's wall. A second setup was established by attaching three piezoelectric sensors at the anterior distal, anterior proximal, and posterior sites. Gait cycle and locomotion movements such as stair ascent and sit to stand were adopted to characterize the validity of the technique. FSR and piezoelectric outputs were measured with reference to the knee angle during each phase. Piezoelectric sensors could identify the movement of midswing and terminal swing, pre-full standing, pull-up at gait, sit to stand, and stair ascent. In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand. FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states. The study highlighted the capacity of using in-socket sensors for knee movement identification. In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types.

No MeSH data available.