The effects of dimensional parameters on sensing and energy harvesting of an embedded PZT in a total knee replacement

Mohsen Safaei; Steven R. Anton

doi:10.1117/12.2219462

15 April 2016 The effects of dimensional parameters on sensing and energy harvesting of an embedded PZT in a total knee replacement

Mohsen Safaei, Steven R. Anton

Author Affiliations +

Proceedings Volume 9799, Active and Passive Smart Structures and Integrated Systems 2016; 97992P (2016) https://doi.org/10.1117/12.2219462
Event: SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, 2016, Las Vegas, Nevada, United States

Abstract

Total Knee Replacement (TKR), one of the most common surgeries in the United States, is performed when the patient is experiencing significant amounts of pain or when knee functionality has become substantially degraded. Despite impressive recent developments, only about 85% of patients are satisfied with the pain reduction after one year. Therefore, structural health and performance monitoring are integral for intraoperative and postoperative feedback. In extension of the author's previous work, a new configuration for implementation of piezoelectric transducers in total knee replacement bearings is proposed and FEA modeling is performed to attain appropriate sensing and energy harvesting ability. The predicted force transmission ratio to the PZT (ratio of force applied to the bearing to force transferred to the embedded piezoelectric transducer) is about 6.2% compared to about 5% found for the previous encapsulated design. Dimensional parameters of the polyethylene bearing including the diameter and depth of the PZT pocket as well as the placement geometry of the PZT transducer within the bearing are hypothesized as the most influential parameters on the performance of the designed system. The results show a small change of 1% and 2.3% in the output of the system as a result of variation in the PZT location and pocket diameter, respectively. Whereas, the output of the system is significantly sensitive to the pocket depth; a pocket 0.01 mm deeper than the PZT transducer leads to no force transmission, and a pocket 0.15 mm shallower leads to full load transmission to the PZT. In order to develop a self-powered sensor, the amount of energy harvested from tibial forces for the proposed geometry is investigated.

Citation Download Citation

Mohsen Safaei and Steven R. Anton "The effects of dimensional parameters on sensing and energy harvesting of an embedded PZT in a total knee replacement", Proc. SPIE 9799, Active and Passive Smart Structures and Integrated Systems 2016, 97992P (15 April 2016); https://doi.org/10.1117/12.2219462

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available