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For producing Carbon Fiber Reinforced Plastics (CFRP) with desired mechanical and physical properties, it is essential to monitor the polymerization process. Therefore, sensors will be embedded in the composite in order to monitor temperature, pressure and/or curing index online. Inlays are foreign-objects in CFRP and behave as a wound in the composite. The composite may resist to foreign-objects. The impact of embedding sensors (inlays) on homogeneity and structural integrity of CFRP is not known yet. The aim of this study is to investigate the influence of embedding inlay on the mechanical properties of CFRP. Inlays of different materials from thick and rigid (silicon with different thicknesses) to soft and flexible (Polyimide and SU8) were embedded in the CFRP composite. These inlays are considered as embedded sensors for online monitoring. The impact of the inlay's different sizes, types and patterns (existence of cavities) on composite were investigated by performing inter-laminar shear strength tests. The results of the inter-laminar shear strength tests clarified that not only can the flexibility of embedded sensors reduce the foreign-object effect of that in the composite, but also altering the size and substrate's patterning can play an important role in improving the properties of composite with the embedded sensors.

This paper presents a wireless system, designed for electrocortical (ECoG) neural recordings, consisting of an implantable flex-rigid ECoG array and a wireless electronic platform. The array is designed for implantation on top of the visual cortex of a Rhesus monkey. The electronic platform contains pre-amplifiers and multiplexer stages, analog-digital converters (ADCs), an in-house developed and reconfigurable ASIC, an RF data transceiver and an inductive energy link. Our ASIC provides user-defined selection of channels (≤128), adjustable channel resolution (1-16bit), sample rate (39S/s-10kS/s), and configurable analog filters. The functionality of the whole system is successfully demonstrated by an in vitro test.

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Implantable invasive neuronal interfaces to the brain are an important keystone for many interesting future medical applications. However, entering this field of research is difficult since such an implant requires components from many different fields of technology. Beside the required amplifiers, analog-digital-converters and data processing, the complete avoidance of wires is important because it reduces the risk of infection and prevents long-term bio-mechanical problems. Thus, means for wireless transmitting data and energy are also necessary.We present a module, containing the necessary components for wireless data transfer and inductive powering for such implantable neural systems, and its base station. They are completely built of commercial off-the-shelf (COTS) components and the design files are available as Open Hardware / Open Source. The data is transmitted via Microsemi ZL70102 transceivers and custom Tx/Rx antennas for bidirectional communication using frequencies in the MICS band, with a maximal data rate of 515 kbit/s. The energy is transmitted via a wireless inductive energy-link based on the Qi standard. On the implant site a handwound litz wire coil harvests energy from the magnetic field and delivers, over a short distance, more than enough inductive power to the fully implantable unit.Based on this wireless module we also present a fully wireless neuronal implant for simultaneously measuring electrocorticographic (ECoG) signals at 128 locations from the surface of the brain. The implant is based on a flexible printed circuit board and is aimed to be implanted under the skull. 1The application-specific integrated circuit (ASIC) was designed in-house and allows to adapt the data processing of the implant to changing user-defined parameters.