A remotely-controlled locomotive IC driven by electrolytic bubbles and wireless powering

Wireless implantable and biodegradable sensors for postsurgery monitoring: current status and future perspectives

In in vivo postsurgery monitoring, the use of wireless biodegradable implantable sensors has gained and is gaining a lot of interest, particularly in cases of monitoring for a short period of time. The employment of biodegradable materials allows the circumvention of secondary surgery for device removal. Additionally, the use of wireless communication for data elaboration avoids the need for transcutaneous wires. As such, it is possible to prevent possible inflammation and infections associated with long-term implants which are not wireless. It is expected that microfabricated biodegradable sensors will have a strong impact in acute or transient biomedical applications. However, the design of such high-performing electronic systems, both fully biodegradable and wireless, is very complex, particularly at small scales. The associated technologies are still in their infancy and should be more deeply and extensively investigated in animal models and, successively, in humans, before being clinically implemented. In this context, the present review aims to provide a complete overview of wireless biodegradable implantable sensors, covering the vital signs to be monitored, the wireless technologies involved, and the biodegradable materials used for the production of the devices, as well as designed devices and their applications. In particular, both their advantages and drawbacks are highlighted, and the key challenges faced, mainly associated with fabrication techniques, and control over degradation kinetics and biocompatibility of the device, are reported and discussed.

Selective Carbon Material Engineering for Improved MEMS and NEMS

The development of micro and nano electromechanical systems and achievement of higher performances with increased quality and life time is confronted to searching and mastering of material with superior properties and quality. Those can affect many aspects of the MEMS, NEMS and MOMS design including geometric tolerances and reproducibility of many specific solid-state structures and properties. Among those: Mechanical, adhesion, thermal and chemical stability, electrical and heat conductance, optical, optoelectronic and semiconducting properties, porosity, bulk and surface properties. They can be affected by different kinds of phase transformations and degrading, which greatly depends on the conditions of use and the way the materials have been selected, elaborated, modified and assembled. Distribution of these properties cover several orders of magnitude and depend on the design, actually achieved structure, type and number of defects. It is then essential to be well aware about all these, and to distinguish and characterize all features that are able to affect the results. For this achievement, we point out and discuss the necessity to take into account several recently revisited fundamentals on carbon atomic rearrangement and revised carbon Raman spectroscopy characterizing in addition to several other aspects we will briefly describe. Correctly selected and implemented, these carbon materials can then open new routes for many new and more performing microsystems including improved energy generation, storage and conversion, 2D superconductivity, light switches, light pipes and quantum devices and with new improved sensor and mechanical functions and biomedical applications.

Extending the Limits of Wireless Power Transfer to Miniaturized Implantable Electronic Devices

Implantable electronic devices have been evolving at an astonishing pace, due to the development of fabrication techniques and consequent miniaturization, and a higher efficiency of sensors, actuators, processors and packaging. Implantable devices, with sensing, communication, actuation, and wireless power are of high demand, as they pave the way for new applications and therapies. Long-term and reliable powering of such devices has been a challenge since they were first introduced. This paper presents a review of representative state of the art implantable electronic devices, with wireless power capabilities, ranging from inductive coupling to ultrasounds. The different power transmission mechanisms are compared, to show that, without new methodologies, the power that can be safely transmitted to an implant is reaching its limit. Consequently, a new approach, capable of multiplying the available power inside a brain phantom for the same specific absorption rate (SAR) value, is proposed. In this paper, a setup was implemented to quadruple the power available in the implant, without breaking the SAR limits. A brain phantom was used for concept verification, with both simulation and measurement data.