Development of a hybrid flywheel/battery drive system for electric vehicle applications

Today's electric vehicles are severely limited in multistop and go driving range and accelerating capability by the lead acid battery's inability to handle high power peaks while maintaining maximum energy storage capability. A hybrid flywheel/battery system can be used to isolate the battery from the accelerating power peaks, and should recover a substantial part of the braking energy. This paper describes the development of a small, high speed, lightweight flywheel/ ac synchronous motor alternator sealed energy storage package coupled into the battery and dc drive motor system through a simple rectifier/inverter power circuit. This system stores just enough energy in the rotor of the machine for one start-stop cycle. Provision is made to add a flywheel to store energy for several cycles, or enough energy for climbing or descending long grades. The fields of the two machines are electronically controlled to achieve optimum performance and effective energy utilization.     

Ferrites for linear applications I?Properties

This two-part tutorial article describes properties and applications of magnetically soft ferrites. These materials, which are characterized by high permeability and low losses, are used in very large quantities as cores for inductors and transformers. This first installment provides an elementary introduction to the processes of magnetization in ferrites. It also includes a survey of available grades and a summary of the technical properties of typical modern ferrites. Part II, to appear in February, reviews the main applications, describing how the material properties and performance requirements come together in the design of the device.     

Control of hybrid nanopositioning systems for trajectory-tracking applications

In many industrial applications positioning systems are required to follow trajectory paths in the range of several centimeters and featuring at the same time a nanometre-range precision. Neither pure piezoelectric stages nor standard positioning systems with motor and spindle are able to meet such requirements as a single actuator, because of the small operation range on the one hand and inadequacies like backlash and friction on the other hand. Hybrid positioning systems, realized as a combination of a “coarse” and a “fine” actuator, aim to solve this problem. The wide range of applications enables a considerable market potential for such devices, but yields changing control requirements due to the high variety of possible positioned objects and positioning tasks and requires therefore a high-performance control system.In this paper a model-based control design for piezoelectric hybrid nanopositioning systems is presented. The proposed control consists of a multivariable state-feedback control on the basis of a novel plant representation offering a sufficient robustness. The designed control is realized and experimentally tested with a commercially available hybrid nanopositioning system featuring a DC drive, representing the coarse actuator, and a piezoelectric actuator utilized as fine actuator.     

Variable gain control circuit for linear applications

A new, simple gain control circuit is introduced for linear applications. It utilises a differential stage for the gain control function and a predistortion circuit to maintain linearity. The circuit provides a wide dynamic range and low intermodulation levels. Suitable applications are WCDMA cellular phone circuits such as variable-gain amplifiers or driver stages with gain control for power amplifiers     

Highly linear amplifier for high gain applications

A novel amplifier structure that compensates nonlinearities by means of a special type of feedback is proposed. The high linearity performance is combined with a high gain that is unreachable with the conventional feedback structure. A practical configuration of the structure is given as an improvement over both a conventional feedback amplifier and a typical feedforward amplifier. Experimental results are provided to verify the high linear characteristic of the practical structure     

基于三频应用的混合谐振器天线设计

提出了一种新的适用于三频应用的混合谐振器天线。该天线辐射结构采用H型金属辐射片并加载矩形介质谐振器,形成混合型谐振器。同时提出一种新的混合馈电方式,使得介质谐振器产生双高阶模,最终形成可工作于三频段的混合型天线。经过优化设计,天线工作频率为1.45～1.63 GHz,3.62～4.1 GHz和4.55～5.86 GHz,其相对带宽分别为11.6%,12.4%和25.2%,天线实测结果表明了该设计的有效性。     

Multi-band hybrid antenna for ultra-thin mobile phone applications

A compact hybrid antenna consisting of two PIFAs and a slot antenna is proposed for ultra-thin mobile phone applications. The antenna has a very compact volume of 46 x 10 x 4.2 mm3, and it operates at GSM 850/900, DCS, PCS, and UMTS bands, simultaneously. Results show that its bandwidth and efficiency are sufficient for these penta-band mobile phone applications.     

A hybrid chaotic map for communication security applications

Recently, the synchronization between two matching chaotic systems to provide confident communication has gained a lot of interest. Continuously, there is a necessity to produce a novel dynamical system to be used in synchronization to implement a strong security system. In this paper, a hybrid chaotic system is suggested and verified for the potential use of secure communication through chaos synchronization. The Lyapunov exponent (LE) and zero‐one (0‐1) tests have been used to verify the performance of the suggested hybrid chaotic system, while National Institute of Standard and Technology (NIST) tests have been applied to verify the randomness properties. And the synchronization has been achieved between master and slave systems by using nonlinear control laws. The simulation outcomes demonstration that the hybrid system has chaotic performance and outstanding randomness characteristic. The statistical results gained for LE test was 0.8822, and for frequency test (FT) was 0.2028, while for the run test (RT) was 0.1924. Accordingly, the suggested hybrid system can be used to evolve functional synchronization algorithms and encryption for image, video, and voice secure communication applications.     

A hybrid pipelined path-searching architecture for multiplecommunications applications

Many communications applications require similar processing functionality but are implemented independently. In particular, a number of applications (including trellis coding, encryption, and speech recognition) use techniques based on shortest path search algorithms. In this paper, we propose a high-throughput architecture that can search for the shortest path within a graph. The architecture can decode any data encoded with a finite state machine (FSM) or data encrypted in a dynamic trellis code and also serve as a specialized processor for other searching and matching applications. Balance between flexibility and hardware efficiency is achieved by an integrated design of architecture, in-place scheduling, and concurrent algorithms     

A hybrid inchworm linear motor

A hybrid linear motor that produces precise resolution with long travelling distance under inchworm motion principle is developed. The motor consists of one push and two clamping devices. The clamping device is innovated using multistack piezoelectric actuators with displacement amplifier since the displacement generated from multistack actuator is not enough for clamping. To secure the large push load and displacement, Terfenol-D magnetostrictive material is used for the push device. Design process of the push and clamping devices is conducted to meet the performance of the motor. The clamping and push devices are assembled and a control sequence is applied. The performance of the inchworm motor is tested in terms of speed and force. The moving speed is increasing when the input frequency and current are increased. To make the performance stable, time tuning between the push and clamping devices signals is necessary. Some remarks on improving the performance of the motor are addressed.     

Compact linear tapered slot antenna for UWB applications

A novel ultra-wideband (UWB) antenna consisting of a linear tapered slot in the ground plane and a microstrip to slotline transition is investigated. The antenna possesses a wide bandwidth from 2.95?14 GHz for |S₁₁| < - dB and shows stable radiation patterns with an average gain of 3 dBi throughout the band. Measured group delay and transmission characteristics indicate that the antenna has good pulse handling capabilities.     

A new design of a linear local-feedback MOS transconductor for low frequency applications

For medical devices, low frequency and low power applications are required, and a transconductor which has a low transconductance is needed. A conventional current division scheme for the low transconductance wastes operating current. This paper proposes an improved local-feedback MOS transconductor operating in subthreshold region. The proposed transconductor is optimally designed using maximally flat approximation method, Newton-Raphson method, and Downhill simplex method. From the optimization, two optimum values are obtained. Characteristics of the proposed transconductor are confirmed by simulation. Transfer characteristics of the proposed transconductor are linear, and the power consumption of the proposed transconductor is 1/60 as compared with the presented transconductor using current division scheme. The CMRR is around 70 dB, and the THD is lower than ?55 dB under a condition of that the frequency of the sinusoidal input is 100 Hz. As a demonstration of an application, the proposed transconductor is applied to a low frequency second order Butterworth filter. A cutoff frequency of the filter is 100 Hz. Simulation results show validities and availability of the proposed transconductor.     

Programmable 2D linear filter for video applications

A fully integrated 2-D linear filter including a line buffer for a 7×7 kernel is presented. To run the filter in real time at video clock frequencies, an array of pipelined carry-save adders was used as a very fast arithmetic unit. The filter chip contains 292451 transistors on a silicon area of 135 mm². The maximum clock frequency under worst-case conditions for technology and temperature was simulated to be 20 MHz. The main blocks are designed as independent parameterizable modules. The line buffer and the arithmetic unit are available as macros in a standard cell library for semicustom design. With these macros a semicustom chip for image enhancement in a X-ray system was produced. This chip works with a system frequency of 13 MHz. The line buffer module is used in another full-custom image processing chip-a two-dimensional rank order filter with a kernel size of also 7×7. This chip contains more than 300000 transistors on a silicon area of 103 mm². In this case the module containing the 1-D FIR (finite impulse response) filters is replaced by additional pixel delays and a sorter module. Simulations have shown that the chip could work with clock frequencies up to 20 MHz     

Ferrites for linear applications II?Performance requirements

The final installment of this article focuses on the applications and performance requirements of soft ferrite materials. Basic devices employing ferrites include inductors for FDM filters, wide-band and pulse transformers, and high-frequency power transformers. In the typical modern television receiver a total of about 0.6 kg of ferrite cores is used in a variety of applications, such as line output transformers, deflection yokes, and convergence systems.     

A linear compact tunable transconductor for Gm-C applications

A CMOS highly linear voltage-controlled transconductor suitable for Gm-C filter design is presented. The control loop to program the transconductance maintains the input transistors in triode region with a compact topology. Measurement results for the transconductor fabricated in a 0.5-??m CMOS technology feature a spurious-free dynamic range (SFDR) of 72?dB for 1 V_pp differential inputs at 1?MHz. The voltage to current converter ensures a high linearity level for a wide transconductance range. Functionality of the transconductor is shown in a fifth-order Gm-C tunable complex filter well suited for a dual-mode Bluetooth/Zigbee transceiver.     

The benefits of interdisciplinary scenario-building for hybrid radio applications

In this paper, we make the case for building interdisciplinary scenarios, integrating technological, business and user perspective during the fuzzy front-end of innovation. We start from a living lab framework, underpinning the iterative process to integrate insights from all three perspectives within research projects. Then, we explain how the approach was applied within the HRADIO project¹. This EU funded project focuses on the development of hybrid radio applications. We demonstrate how the process of building interdisciplinary scenarios and the involvement of multiple perspectives to evaluate these scenarios, has enabled both strategic decision making (1) and improved the technical development process within the HRADIO project (2). The first focuses on the (lack of) interest in certain scenarios from a business, technology and/or user perspective, to explain: (a) how these thresholds can be overcome and (b) what the consequences are for the project. The latter explains how we moved from interdisciplinary scenarios to a first Minimum Viable Product (MVP) that could be tested in the first pilot phase, to prototypes to be tested in the second pilot phase. To validate the importance of the scenarios, we also explain how the scenarios are integrated into the exploitation timeline. Finally, and importantly, we address how the process of multidisciplinary scenario building and evaluation can be improved.     

ANN-based design of hybrid fractal antenna for biomedical applications

In this research paper, the development of an artificial neural network (ANN) model for the designing of a compact dual-band hybrid fractal antenna (CDHFA) that covers Wireless Medical Telemetry Service and industrial, scientific and medical (ISM) bands are described. The projected CDHFA is designed by using 1.6mm thick, FR4 substrate whose permittivity is 4.4 and obtained by the combination of different fractal geometries. The dimensions of the projected CDHFA are interlinked with each other. A set of 80 CDHFAs with different dimensions is designed to obtain a data dictionary for the implementation of ANN. From the experimental results, it is depicted that the resonant frequencies are 1.4290 and 2.4380 GHz with S(1,1) values ?12.4 and ?15.72 dB, respectively. A comparison between feed forward back propagation network, generalised regression neural network and desired outputs in terms of average absolute error is also done. The simulation, experimental and ANN results are well matched that indicates the effectiveness and accuracy of the developed ANN model for biomedical applications.     

Development of a miniature pressure transducer for biomedical applications

Miniature absolute pressure transducers are needed for biomedical implant applications. The design parameters are: 1) sensitivity, 2) size, 3) hysteresis, 4) temperature coefficient, 5) long-term stability, and 6) biocompatibility. The present devices cannot meet all the requirements, particularly in size, long-term stability, and biocompatibility. The results of a development program on implantable and indwelling pressure transducers are reported with emphasis on the study of long-term stability and reproducibility associated with reduced size. The sensor is a resistive bridge diffused on a