8/4-4分载式并联六维力传感器建模与分析

为增大传感器量程,适应大负载要求,基于8/4-4并联压电六维力传感器,提出了一种8/4-4分载式并联结构的六维力传感器。基于大力分载原理,在8/4-4并联压电六维力传感器的基础上,各个支链采用压电陶瓷作为敏感元件,增加中心承载梁,使其分载传感器的大部分外负载广义六维力。建立8/4-4分载式并联六维力传感器的数学模型,并推导其解耦算法。通过ADAMS算例仿真与理论模型进行对比,六维力传感器的数学模型及解耦算法的误差不超过0.14%,验证了其准确性。     

Dynamics modelling and control of the 3-RCC translational platform

The article presents the inverse dynamics model of a novel translating parallel machine and proposes the structure of a force controller for the execution of tasks characterised by interaction with the environment. The task space model of machine’s dynamics is obtained in an efficient and compact form by means of the principle of virtual work. A virtual prototyping environment has been set up to test by computer simulation the potential of such kinematic architecture: the resulting dynamics is rather poor, mainly due to the high moving masses, but it is shown that hybrid position/force control schemes should be able to provide good performances, including the case of rather difficult operations, such as the peg-in-hole assembly.     

Sensor data fusion using perception net for a precise assembly task

A sensor fusion method is presented for a peg-in-hole insertion task. Three kinds of sensor are fused for task execution. The vision and proximity sensors are mainly used for gross motion control, and the force/torque sensor is used for fine motion control of the robot. Covariance analysis is conducted for each sensor discussed in this paper, and the perception net is introduced to improve the usefulness of each sensor by optimally weighting its output.     

Hierarchical fuzzy force control for industrial robots

In this paper, we present a hierarchical force control framework consisting of a high-level control system based on fuzzy logic and the existing motion control system of a manipulator in the low level. In order to adapt various contact conditions, an adaptable fuzzy force control scheme has been proposed to improve the performance. The ability of the adaptable force control system is achieved by tuning the scaling factor of the fuzzy logic controller (FLC). A Mitsubishi MELFA RV-M1 industrial robot equipped with a BL Force/Torque sensor is utilized for implementing the hierarchical fuzzy force control system. Successful experiments for various contact motions are carried out. Additionally, discussion of a peg-in-hole insertion is presented, and the experimental results are given     

A low cost 3-DOF force sensing unit design for wrist rehabilitation robots

In this study, a low cost and modular three degree-of-freedom force sensor design is developed for the purposes of wrist rehabilitation. The proposed sensor in this study and the existing sensors in the literature are compared to each other considering nine main topics namely, measurement capability, design purpose, measurement approach, force limits, dimensions, producing & assembly complexity, producing cost, modularity and electronics. The comparison results are given as a table. Considering the sensors developed especially for the purpose of wrist rehabilitation in the literature, the proposed sensor has some advantages as follows: The proposed sensor has i) modular structure, ii) less producing & assembly complexity, iii) low cost and iv) integrated electronic and mechanical structures. A specific experimental setup is also developed for both performing force measurements and control of flexion/extension movements. Linearity, hysteresis and repeatability errors of proposed multi-axis force sensor unit are given as table. A set of force measurements is carried out using this experimental setup. Measurements are illustrated as figures. It can be concluded that the proposed force sensor can be used for human-robot interaction in wrist rehabilitation.     

Optimal design of a hyperstatic Stewart platform-based force/torque sensor with genetic algorithms

This paper proposes a novel hyperstatic six-component force/torque sensor structure based on the Stewart platform, and presents the parameter optimization of the sensor structure with genetic algorithms. The structure characteristic of the hyperstatic sensor is analyzed compared with the traditional Stewart platform-based sensor. The mathematical expression of the sensor’s force mapping matrix is built by using the screw theory. In this paper, the condition number and generalized amplifying index are used to evaluate the isotropy and sensitivity of the sensor, respectively. Based on genetic algorithms, the optimal design of the sensor structure is performed with the objective of achieving high measurement sensitivity and well-conditioned transformation between the input and output forces. The computed results prove the better performance of the proposed sensor structure and the effectiveness of the optimization algorithm.     

基于光纤光栅的机器人多维力传感技术研究

研究了一种光纤Bragg光栅(FBG)机器人多维力传 感器,进行了传感器弹性体的静 态、模态和动态有限元ANSYS模拟,获得弹性体在各方向受力与力矩时应力、应变的变化情 况。在模拟的基础上, 设计、制作出传感器机械结构,敷设FBG和搭建测试系统,并在压力与扭矩实验机上进行了 有关测试;为模拟机器 人腕部受冲击现象,进行传感器动态冲击实验。各种实验分析表明:本文传感器具有良好的 线性度和重复性,灵敏度 可达0.000nm/N,且具有结构设计简单、免受 电磁干扰、稳定性好和成本低等优点。     

Resonant sensors for multi-axis force and torque estimation in collaborative robotics

This paper presents a complete design methodology for a multi-axis resonant force sensor. The proposed device has been designed to be useable in a context of physical interaction between robots and humans. The proposed solution allows the three force components and the three torque components to be measured simultaneously and can be inserted into an interface handle or a robot end-effector. The information on wrench can then be used to detect and control interactions for cooperative tasks between humans and robots. In the context of sensors for robotic co-manipulation, it is imperative to guarantee not only a certain level of performance (accuracy, dynamics, size) but also to guarantee certain non-functional specifications associated with safety, measurement redundancy or functional integration of the sensor into its environment. The consideration of all these design specifications, both functional and non-functional, led to the principles and technologies used to develop this sensor. Multi-axis resonant sensors have excellent performance and safety characteristics, two key elements for collaborative robotics, but the literature review did not reveal any significant previous work in this area. Thus, this paper proposes an original sensor based on a breakthrough technology in the crucial field of multi-axis force sensors. The performances obtained on our prototype are already close to the performances of the best existing 6-axis industrial sensors, which suggests very good prospects for this new technology. In addition, and compared to alternative technologies, resonance technology offers new possibilities in terms of sensor fault detection, thus improving the intrinsic safety of these devices.     

红外吸收粉尘传感器的设计

基于粉尘对红外光的吸收原理提出了一种测量粉尘浓度的传感器新方案。以朗伯-比尔定律为理论依据,传感器采用空间双光路结构,应用差分算法,建立数学模型,采用MSP430F149,ICL7605和AD620等芯片进行数据处理,并用实验结果验证可靠性。提出的粉尘设计方案对于提高粉尘测量精度,特别是烟道、煤矿中高浓度的粉尘安全检测均有重要意义。     

一种简单的电容式三维力柔性触觉传感器设计

随着机器人智能化程度不断提高,机器触觉和机器视觉技术均得到了很大发展,但是目前大部分触觉传感器均不能满足触觉感知应用的要求。因此,提出了一种新型的具有滑觉检测功能的柔性三维力触觉传感器。该传感器能够将力量变化转化为气隙变化,进而引起电容发生变化。然后将接触力建模为实测电容的多项式函数,对传感器输出进行校正进而实现法向力测量和滑动检测。测试结果显示,提出的传感器能够以较高的精确度测量法向力,重复性好,并且能够检测滑动现象,在0-100mN测量范围内的法向灵敏度约为0.4 pF/N,均方根误差为1%。此外提出的传感器结构简单、成本较低,易于大规模生产和应用。     

压电石英推力与推力矢量传感器的研制

介绍了一种压电石英推力与推力矢量传感器,建立了传感器力系等效转换数学模型。采用有限元分析预估了推力与推力矢量传感器的固有频率,并通过实验模态分析法对传感器进行了精确测试,得出了传感器系统的前4阶固有频率、阻尼比和留数等模态参数;通过静态力加载实验获得了传感器的各项静态性能指标。结果表明:该压电石英推力与推力矢量传感器具有良好的静态和动态特性指标、线性度、重复性以及固有频率等参数都达到CIRP-STCC规定的测力仪使用标准。     

基于光纤光栅的软体机器人末端力测量方法研究

手术机器人的末端操作力测量是实现机器人精准控制的关键,对保证手术操作的安全性至关重要。文中针对微创手术软体机器人末端三维力测量的实际需求,提出一种基于光纤光栅的微创软体机器人末端三维力的测量方法。基于光纤光栅传感原理,分析光纤传感器植入在软体机器人中的传感特性,建立基于最小二乘法线性标定和基于伯恩斯坦多项式非线性补偿的软体机器人末端力解耦模型,研究光纤光栅中心波长漂移量和软体机器人末端三维力之间的关系。并通过实验测试和对比分析验证了基于线性标定和非线性解耦算法的光纤传感软体机器人末端力测量性能研究结果表明:光纤光栅传感的可重复性平均为1.5 pm,末端力在XYZ三个方向上的测量精度误差均低于满量程的5%,且残差分布大部分集中在可靠区间,具有良好的重复性。所提出的基于光纤光栅的软体机器人末端力解耦算法为微创手术软体机器人的末端力精确测量提供了有效的方法,在生物医学等软体机器人的末端力测量中具有应用前景。     

A novel wide measuring range FBG displacement sensor with variable measurement precision based on helical bevel gear

The goal of Optoelectronics Letters is to rapidly report original,new and important results in the fields of photonics and optoelec-tronics in English,to advance the international academic exchanges.Optoelectronics Letters pays a particularly attention to the cross topics between photonics and electronics.The scope of Optoelectronics Letters is as follows:Novel OEdevices and applications;New materials and functional components;Nano-structures and OE integration;Nano-quantum optoelectronics;     

Simply supported, ‘Joint less’ parallel mechanism based force–torque sensor

The platform of a hexapod is constrained to be a part of the structure whose six degrees of freedom are constrained by six linearly independent line constraints. The six line constraints are utilized for developing simply supported, ‘joint less’ six component parallel mechanism based force–torque sensor. The idea, model analysis, mechanical design and instrumentation are presented. The validity of the design is proved with prototype arrangements, two practical numerical examples and experimental results.     

准静态电荷放大器的研究

准静态电荷放大器是压电传感器测试和标定系统的重要组成部分。为了对差动式压电六维力传感器做进一步的深入研究,该文对“力电”准静态电荷放大器进行了较深入的研究,推导了实现准静态电荷放大器的相关技术参数,制作了准静态电荷放大器,并将实验测试的下限频率与现有电荷放大器在同等条件下的低频下限进行了对比,实验结果达到了设计要求。     

红外传感器采样与光学模糊效应的仿真研究

准确逼真地生成红外目标的仿真图像需要准确模拟红外传感器效应。采样和光学模糊效应是红外传感器典型的主要效应。首先讨论了采样和模糊效应的数学模型。然后,同时考虑这两种效应,采用光线追迹的方法将两种效应的算法融合成一种,提出一种新的数学模型。根据建立的模型,得到采样与光学模糊效应共同作用的仿真图像。实验结果表明,所建立的仿真模型能够体现出采样和模糊效应对图像的退化作用,有利于提高计算的准确性和有效性,提高了红外图像模拟的置信度。     

三角剪切式微震监测压电加速度传感器设计

针对现有应用于矿井突水动力灾害防治微震监测传感器存在灵敏度低及频率范围窄的问题,该文提出了一种基于三角剪切式结构的微震监测压电加速度传感器。首先建立了压电加速度传感器的力学模型,对与固有频率和灵敏度有关的结构及材料参数进行了分析;然后设计了三角剪切型压电加速度传感器结构,探讨了压电陶瓷材料的选择,再利用ANSYS建立了压电加速度传感器有限元结构模型,分别对传感器进行模态分析、谐振响应分析与压电分析。仿真结果表明,设计的压电加速度传感器的工作频率和灵敏度满足微震监测要求。最后对设计的压电加速度传感器进行了标定和微震信号检测试验。结果表明,该传感器的谐振频率为6 300 Hz,工作频率为0.1~2 100 Hz,电荷灵敏度为34.626 pC/(m·s^-2)时,可完成对微震信号的检测,且具有宽频率范围和高灵敏度。     

嵌入元器件板推力研究

由于电子元器件组装及后续的设备安装运行过程中对于嵌入式器件与PCB的结合力（常用推出力表征）的严格要求,在制作含嵌入式器件PCB的过程中,需重点研究影响嵌入式器件推出力的因素及其控制方法。本项目设计正交试验,以PCB板厚、嵌入式器件锯齿数量、器件嵌入PCB开槽内的深度以及PCB开槽内镀铜厚度等四个因子各2两个水平进行试验研究,从而得出不同嵌入式器件推出力需求下的PCB板厚设计、嵌入式器件设计以及其它相关工艺参数等设计准则。     

Whole-Body Force Sensation by Force Sensor With Shell-Shaped End-Effector

This paper proposes a tactile-sensing mechanism for a robot. The mechanism is composed of a force-sensor device and an end-effector of shell shape. Since the end-effector plays the role of an outer shell, a force can be sensed at any position on the body. Due to the aspect of its intrinsic contact sensing, position of the single contact point is calculable without any sensor array. Another advantage is that the six-axis resultant force is measurable. This paper shows that the mechanism is also available for the end-effector with an angulated shape. The only condition for the shape is to be a convex hull. Some experimental results evaluate sources of error in practical measurement and show the validity of the proposed mechanism.     

基于安全火花试验装置的电感分断电弧电阻建模研究

研究电感分断放电电弧电阻模型是建立电感电路非爆炸本安性能评价的基础.运用IEC安全火花试验装置对电感分断电弧放电特性进行试验研究,深入分析电弧电阻随放电时间的变化规律,并采用非线性回归的方法得出分断电弧放电时间与电感和初始电流之间的函数关系式.考虑安全火花试验装置钨丝和镉盘电极结构特点,建立了一种极间电弧放电区域的物理模型,并推断出二维泊松方程的边界条件.基于此,利用分离变量法求解泊松方程,推导出电弧电阻的数学表达式,得出了电感分断电弧放电电压和电流的关系表达式.仿真分析及实验结果证明了理论分析及所提出电弧电阻数学模型的准确性和可行性.