A wearable sensing glove for monitoring hand gestures and posture has been developed. The glove sensing capability is based on optical fiber Bragg gratings (FBGs) sensors. These sensors, due to their inherent self-referencing and multiplexing capability, are a value-added choice for this application. A single optical fiber would cross all the hand with Bragg structures in specific spots, as the finger joints. The functionality and performance of the glove was fully evaluated. The sensor response was linear to the hand movements for opening and closing down. Through the sensor response, it was possible to retrieve information about the joint angles from which other set of information like finger force can be estimated. The developed glove was able to provide numerical data about the angles of the hand posture in real time. The simplicity of the system and performance makes it well suitable for physical therapy applications, study of the human kinematics during sport activity, virtual reality or even remote control applications, among others.
6 April 2015 in IEEE Journal of Solid-State Circuits
A complementary p-n class-B oscillator with two magnetically coupled second harmonic tail resonators is presented and compared to an N-only reference one. An in depth analysis of phase noise, based on direct derivation of the Impulse Sensitivity Function (ISF), provides design insights on the optimization of the tail resonators. In principle the complementary p-n oscillator has the same optimum Figure of Merit (FoM) of the N-only at half the voltage swing. At a supply voltage of 1.5 V, the maximum allowed oscillation amplitude of the N-only is constrained, by reliability considerations, to be smaller than the value that corresponds to the optimum FoM even when 1.8 V thick oxide transistors are used. For an oscillation amplitude that ensures reliable operation and the same tank, the p-n oscillator achieves a FoM 2 to 3 dB better than the N, only depending on the safety margin taken in the design. After frequency division by 2, the p-n oscillator has a measured phase noise that ranges from -150.8 to -151.5 dBc/Hz at 10 MHz offset from the carrier when the frequency of oscillation is varied from 7.35 to 8.4 GHz. With a power consumption of 6.3 mW, a peak FoM of 195.6 dBc/Hz is achieved.
1 November 2010 in Sensors and Actuators A: Physical
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.
1 December 2014 in Sensors and Actuators B: Chemical