Power sensitivity of vibration energy harvester

This paper deals with a power sensitivity improvement of an electromagnetic vibration energy harvester which generates electrical energy from ambient vibrations. The harvester provides an autonomous source of energy for wireless applications, with an expected power consumption of several mW, placed in environment excited by ambient mechanical vibrations. An appropriately tuned up design of the harvester with adequate sensitivity provides sufficient generating of electrical energy for some wireless applications and maximal harvested power depends on a harvester mass, frequency and level of the vibration and sensitivity of the energy harvester. The design of our harvester is based on electromagnetic converter and it contains a unique spring-less resonance mechanism where stiffness is provided by repelled magnetic forces. The greater sensitivity of the harvester provides more generated power or decrease of the harvester size and weight.     

Artificial intelligence based optimization for vibration energy harvesting applications

This paper deals with optimization studies based on artificial intelligence methods. These modern optimization methods can be very useful for design improving of an electromagnetic vibration energy harvester. The vibration energy harvester is a complex mechatronic device which harvests electrical energy from ambient mechanical vibrations. The harvester design consists of a precise mechanical resonator, electromagnetic converter and electronics. The optimization study of such complex mechatronic device is complicated however artificial intelligence methods can be used for set up of optimal harvester parameters. Used optimization strategies are applied to optimize the design of the electro-magnetic vibration energy harvester according to multi-objective fitness functions. Optimization results of the harvester are summarized in this paper. Presented optimization algorithms can be used for a design of new energy harvesting systems or for improving on existing energy harvesting systems.     

Advanced model predictive control framework for autonomous intelligent mechatronic systems: A tutorial overview and perspectives

This paper presents a review on the development and application of model predictive control (MPC) for autonomous intelligent mechatronic systems (AIMS). Starting from the conceptual analysis of “mechatronics”, we analyze the characteristics and control system design requirements of AIMS. In order to fulfill the design requirements, we propose to develop a unified MPC framework for AIMS. The main MPC schemes, covering MPC basics, robust MPC, distributed MPC, Lyapunov-based MPC, event-based MPC, network-based MPC, switched MPC, fast MPC, are reviewed with an attempt to document some of the key achievements in the past decades. Furthermore, we provide the review and analysis of MPC applications to three types of mechatronic systems, including unmanned aerial vehicles (UAVs), autonomous marine vehicles (AMVs), and autonomous ground robots (AGRs). Some promising research directions and concluding remarks are presented.     

谐振频率转换机制振动能采集器研究进展

环境振动能采集器可为低功耗系统提供绿色环保、可再生能源,具有寿命长久、能量密度高、微型、易集成等优势.能量采集环境具有随机振动频率低、频域广、振源幅值小且多方向性等特点,频率转换机制可有效解决采集器与环境振动频率不匹配问题,提高其能量转换效率.发电装置中的拾振结构频变方式主要分为接触式和非接触式,具体操作方法包括直接或间接碰撞拾振体、驱使振动体形变、磁力耦合调频等.综合比较了各类频率转换机制的优缺点及其实用性,指出了低宽频、高效能、智能化是未来振动能采集微电源的研究趋势.     

Micro harvester using isotropic charging of electrets deposited on vertical sidewalls for conversion of 3D vibrational energy

The design and fabrication process of an integrated micro energy harvester capable of harvesting electrical energy from low amplitude mechanical vibrations is presented. A specific feature of the presented energy harvester design is its capability to harvest vibrational energy from different directions (3D). This is done through an innovative approach of electrets placed on vertical sidewalls, allowing miniaturization of 3D capacitive energy harvester fabrication on monolithic CMOS substrates. A new simple electret charging method using ionic hair-dryers is used. The charging performance of SiO₂ and CYTOP electrets are characterized for electrets in horizontal arrangement and electrets deposited on vertical sidewalls.     

Energy storage options for wireless sensors powered by aircraft specific thermoelectric energy harvester

This paper describes an approach for efficiently storing the harvested energy from a thermoelectric module for powering autonomous wireless sensor nodes in aircraft health monitoring applications. Thermoelectric devices are the preferred option due to the widespread availability of significant levels of energy from the temperature gradients or variations at the aircraft, such as the cabin, the engine compartment, the fuel tanks or the inner and outer frame of the fuselage. Batteries and supercapacitors are popular choices of storage device, but neither represents the ideal solution, with, supercapacitors possessing low energy densities while batteries have low power density. When using a battery-only solution for storage, the runtime of a typical sensor node is typically reduced by the battery’s relatively high internal impedance and thermal loss. Supercapacitors can overcome some of these problems, but generally do not provide sufficient long-term energy to allow aircraft health monitoring applications to be operated over an extended period. A hybrid energy storage solution can provide both energy and power density to a wireless sensor node simultaneously. Techniques such as acoustic–ultrasonic, acoustic-emission, strain and crack wire sensors require storage approaches that can provide immediate energy on demand, usually in short, high intensity bursts, and that can be sustained over long periods of time, storing up to 40–50 J of energy. This application requirement is considered as a significant constraint when working with battery-only and supercapacitor-only solutions. The hybrid system described here provides an alternate viable solution.     

On the mechatronic servo bandwidth of a stewart platform for active vibration isolating in a super antenna

As being independent of the magnitude of reference input signal, the conventional concept of servo bandwidth stemming from electronics fails to reflect the ability of the multiple degree-of-freedom (DOF) mechatronic system to perform vibration control. Considering the magnitude and frequency of reference input signal, a novel definition of mechatronic servo bandwidth of the Stewart platform-based active vibration isolator for a super antenna is proposed firstly. Then its mechatronic servo bandwidth is theoretically evaluated according to electrical and mechanical performances by using an optimization method. Experiments were conducted on the Stewart platform prototype, and the results validate the definition of and solution to the mechatronic servo bandwidth. From the application point of view, the mechatronic servo bandwidth can be employed to measure the manipulating rapidity of a multiple DOF mechatronic system and the range of vibrations that an isolator is able to overcome.     

基于GMM的轨道无线传感网络能量收集装置研究

随着轨道无线传感器网络技术的推广,改善无线传感器的供电问题显的刻不容缓。研究一种基于超磁致伸缩材料（GMM）的轨道振动能量收集器,将收集器安装于钢轨与轨道板之间,收集钢轨的振动能。建立车辆轨道垂向耦合模型,将钢轨垂向位移和支反力作为能量收集器的激振源。利用超磁致伸缩材料的维拉里效应,将振动能转换为电能。经过MATLAB理论分析,能量收集器大致能收集到能量大约237.1584 J。收集的电能足以解决无线传感器的供电问题。     

Wireless sensor node powered by aircraft specific thermoelectric energy harvesting

An energy autonomous wireless sensor system consisting of an energy harvesting power source, an energy management unit and a low power wireless sensor node is tested for aircraft applications. The autonomous power source combines aircraft specific outside temperature changes with a thermoelectric generator (TEG) and a heat storage unit. The temperature difference generated with the latter component artificially at the TEG is used to power the sensor node by thermoelectricity. Additionally, a high efficient low input voltage power management circuit is necessary to store the generated energy and to convert it to higher voltage levels needed to operate the sensor. The experimental data are compared with results from numerical simulation models to predict the energy conversion in the heat storage - TEG system. A new TEG prototype is tested and the energy output is improved by 14%. The power management storage capacitors are adapted to the available energy, thereby increasing storage voltage and conversion efficiency. Doing so, the efficiency of the complete system can be increased by around 50%.     

Electromagnetic vibration energy harvesting device optimization by synchronous energy extraction

This paper investigates a new application of nonlinear techniques for vibration energy harvesting. The Synchronous Electric Charge Extraction (SECE) energy harvesting technique for piezoelectric generators is extended and adapted to electromagnetic generators. This new circuit, which is the dual of the SECE circuit, is named SMFE for Synchronous Magnetic Flux Extraction. A theoretical model is developed, and the harvested power is simulated. Comparisons with a classical energy extraction approach show that between 2.5 more power and 10% less power can be harvested, depending on the generator characteristics. It also allows the maximum power to be harvested whatever the value of the load. Finally, the SMFE circuit was embedded and tested on a simple centimeter-scale electromagnetic harvester. Measurements confirm the theoretical operating principle of the circuit.     

圆片级低真空封装的MEMS压电振动能量收集器结构设计

MEMS低真空封装技术能为MEMS器件的可动部分提供低阻尼环境,降低能量损耗,有效提高器件的能量转换效率,具有重要的研究意义和应用前景,是MEMS技术的研究热点和难点。为了进一步提高MEMS压电振动能量收集器的输出性能,提出了圆片级低真空封装的共质量块MEMS压电悬臂梁阵列振动能量收集器新结构,通过有限元分析方法对器件结构参数进行了优化设计,在优化结构参数下仿真器件输出性能：在610 Hz、2 gn加速度下,器件的输出电压为8.88 V,输出功率为1220μW,能满足实际应用需求;根据器件结构设计了加工工艺流程,对低真空封装结构的实现和封装工艺探索具有重要意义。     

A general dynamic vision architecture for UGV and UAV

The expectation-based 4D approach to dynamic machine vision exploiting integral spatiotemporal models of objects in the real world is discussed in the application domains of unmanned ground and air vehicles. The method has demonstrated superior performance over the last half decade in autonomous road vehicle guidance with three different vans and busses, with an AGV on the factory floor and with completely autonomous relative state estimation for a twin turboprop aircraft in the landing approach to a runway without any external support; in all application areas only a small set of conventional microcomputers was sufficient for realizing the system. This shows the computational efficiency of the method combining both conventional engineering type algorithms and artificial intelligence components in a well balanced way.The modularity of the approach is demonstrated in a simulation set-up serving both the ground- and the air vehicle applications. Expermental results in both areas are discussed.     

A multirobot system for autonomous deployment and recovery of a blade crawler for operations and maintenance of offshore wind turbine blades

Offshore wind farms will play a vital role in the global ambition of net zero energy generation. Future offshore wind farms will be larger and further from the coast, meaning that traditional human-based operations and maintenance approaches will become infeasible due to safety, cost, and skills shortages. The use of remotely operated or autonomous robotic assistants to undertake these activities provides an attractive alternative solution. This paper presents an autonomous multirobot system which is able to transport, deploy and retrieve a wind turbine blade inspection robot using an unmanned aerial vehicle (UAV). The proposed solution is a fully autonomous system including a robot deployment interface for deployment, a mechatronic link-hook module (LHM) for retrieval, both installed on the underside of a UAV, a mechatronic on-load attaching module installed on the robotic payload and an intelligent global mission planner. The LHM is integrated with a 2-DOF hinge that can operate either passively or actively to reduce the swing motion of a slung load by approximately 30%. The mechatronic modules can be coupled and decoupled by special maneuvers of the UAV, and the intelligent global mission planner coordinates the operations of the UAV and the mechatronic modules for synchronous and seamless actions. For navigation in the vicinity of wind turbine blades, a visual-based localization merged with the location knowledge from Global Navigation Satellite System has been developed. A proof-of-concept system was field tested on a full-size decommissioned wind-turbine blade. The results show that the experimental system is able to deploy and retrieve a robotic payload onto and from a wind turbine blade safely and robustly without the need for human intervention. The vicinity localization and navigation system have shown an accuracy of 0.65 and 0.44 m in the horizontal and vertical directions, respectively. Furthermore, this study shows the feasibility of systems toward autonomous inspection and maintenance of offshore windfarms.     

A multi-agent methodology for multi-level modeling of mechatronic systems

Mechatronic design aims to integrate the models developed during the mechatronic design process, in order to be able to optimize the overall mechatronic system performance. A lot of work has been done in the last few years by researchers and software developers to achieve this objective. However, the level of integration does not yet meet the purposes of mechatronic system designers, particularly when dealing with modeling changes. Therefore, new methodologies are required to manage the multi-view complexity of mechatronic design. In this paper, we propose a multi-agent methodology for the multi-abstraction modeling issue of mechatronic systems. The major contribution deals with proposing a new method for the decomposition of the multi-level design into agents linked with relationships. Each agent is representing an abstraction level and both agent and relationships are managed with rules. By considering an application to a piezoelectric energy harvesting system, we show how we associate agents, rules and inter-level relationships to multi-abstraction modeling. We also show how modeling errors are identified using this approach.     

基于振动能量采集器的无源无线传感节点技术研究

随着以MEMS技术为依托,结合压电效应的振动能量采集技术的日臻完善,如何利用振动能量采集器构成高效的无源无线传感节点成为近期研究热点,而能量采集器输出的电能储存控制和低功耗发射技术是实现该节点的难点。在设计出对储能电容电压具有双阈值检测与控制功能的低功耗电路基础上,给出了一种自报警、无源无线低功耗传感节点。实验表明,在频率52 Hz正弦振动、振动加速度幅值为5 gn激励下,经过125 s的能量储存,节点能够以+10 dBm功率在16 ms内完成发射及无线报警,发射距离可达1.31 km。该节点构成的无线传感网络可广泛应用于石油管线、桥梁和军事侦察等外部供电极度受限环境的现场监控等用途。     

Simulations,fabrication, and characterization of d31 mode piezoelectric vibration energy harvester

This paper presents the development work on d₃₁ mode piezoelectric vibration energy harvester. The device structure consists of a fixed-free type cantilever beam with a seismic mass attached at the free end of the beam. On top of the cantilever beam, a ZnO piezoelectric layer is sandwiched between two metal electrodes. The harvester is designed using an FEM tool CoventorWare. The simulations are carried out to estimate the resonance frequency, mises stress, optimal load resistance, and generated power. The optimized design is then implemented using a five mask SOI bulk micromachining process. The fabricated harvester is characterized for frequency response using Polytec MSA-500 Micro System Analyzer. The experimental resonance frequency is found to be 235.38 Hz. The harvester is also evaluated for generated open-circuit voltage when subjected to harmonic acceleration. The open-circuit peak-to-peak voltage for 0.1 g acceleration is found to be 306 mV.

     

一个用于汽车HIL仿真器的三维虚拟现实的实现

自上个世纪八十年代以来，汽车行业在将机电一体化工程应用于汽车产品方面取得了突破性的进展。在这一过程中，各类仿真器被广泛运用于汽车产品的开发。这反过来又推动了相关仿真器本身的研究与发展。文中介绍了为一个汽车HIL实时仿真器开发的三维虚拟现实的实现方案。     

Efficient nonparametric identification for high-precision motion systems: A practical comparison based on a medical X-ray system

The need for accurate knowledge of complex dynamical behavior for high-performance mechatronic systems led to the development of a vast amount of nonparametric system identification approaches over the recent years. The aim of this paper is to compare several proposed methods based on experiments on a physical complex mechanical system to bridge the gap between identification theory and practical applications in industry where basic identification approaches are often the norm. Typical practical implications such as operation under closed-loop control, multivariable coupled behavior and nonlinear effects are included in the analysis. Finally, a possible approach for fast and reliable identification is illustrated based on measurement results of an interventional medical X-ray system.