Performance of piezoelectric and triboelectric transducers under gait loading for energy harvesting and load monitoring in total knee replacements.

This study investigates the energy harvesting and sensing capabilities of piezoelectric nanogenerators (PENG) and triboelectric nanogenerators (TENG) for long-term load monitoring in total knee replacement (TKR). Multi-layered polyvinylidene fluoride (PVDF) films and cuboid-patterned silicone rubber embedded with dopamine-coated BaTiO particles (SR/BT@PDA) TENG are compared as energy harvesting-based load sensors. Unlike prior studies relying on simplified harmonic loading, this work utilizes physiologically relevant gait cycles covering realistic force ranges to precisely evaluate electrical output, sensitivity, and activity recognition capabilities.

3D printed CNT/TPU triboelectric nanogenerator for load monitoring of total knee replacement.

This study presents the development and characterization of a novel triboelectric nanogenerator (TENG) designed as a self-powered sensor for load monitoring in total knee replacement (TKR) implants. The triboelectric layers comprise a 3D-printed thermoplastic polyurethane (TPU) matrix with carbon nanotube (CNT) nanoparticles and kapton tape, sandwiched between two copper electrodes. To optimize sensor performance, the proposed CNT/TPU TENG sensor is fabricated with varying CNT concentrations and thicknesses, enabling a comprehensive analysis of how material composition and structural parameters influence energy harvesting efficiency.

Toward Self-Powered Load Imbalance Detection for Instrumented Knee Implants Using Quadrant Triboelectric Energy Harvesters.

In this study, we proposed a triboelectric nanogenerator (TENG) as a pressure sensor to measure the load imbalance on the tibial tray. To detect the load imbalance, we proposed a segmented quadrant design. The TENG pressure sensors with various micro-patterns, including pyramid, cylindrical, and bar patterns, are utilized to measure the axial forces with different sensitivity in different quadrants of the tibial tray.

Hybrid triboelectric-piezoelectric nanogenerator for long-term load monitoring in total knee replacements.

A self-powered and durable pressure sensor for large-scale pressure detection on the knee implant would be highly advantageous for designing long-lasting and reliable knee implants as well as obtaining information about knee function after the operation. The purpose of this study is to develop a robust energy harvester that can convert wide ranges of pressure to electricity to power a load sensor inside the knee implant. To efficiently convert loads to electricity, we design a cuboid-array-structured tribo-pizoelectric nanogenerator (TPENG) in vertical contact mode inside a knee implant package.

Covert Channel Communication as an Emerging Security Threat in 2.5D/3D Integrated Systems.

In this paper, first, a broad overview of existing covert channel communication-based security attacks is provided. Such covert channels establish a communication link between two entities that are not authorized to share data. The secret data is encoded into different forms of signals, such as delay, temperature, or hard drive location.

Self-Powered Load Sensing Circuitry for Total Knee Replacement.

There has been a significant increase in the number of total knee replacement (TKR) surgeries over the past few years, particularly among active young and elderly people suffering from knee pain. Continuous and optimal monitoring of the load on the knee is highly desirable for designing more reliable knee implants. This paper focuses on designing a smart knee implant consisting of a triboelectric energy harvester and a frontend electronic system to process the harvested signal for monitoring the knee load.

A Smart Knee Implant Using Triboelectric Energy Harvesters.

Although the number of total knee replacement (TKR) surgeries is growing rapidly, functionality and pain-reduction outcomes remain unsatisfactory for many patients. Continual monitoring of knee loads after surgery offers the potential to improve surgical procedures and implant designs. The goal of this study is to characterize a triboelectric energy harvester under body loads and to design compatible frontend electronics to digitize the load data.