语音交互与力感知式智能牙周探针开发

针对当前牙周探针在探诊力控制和探诊参数自动记录方面的不足,开发并验证了一种便携无线的语音交互与力感知式智能牙周探针,建立了探针力感知计算模型,完成了探针软硬件开发和语音交互探诊实验。其中,探针力感知模型计算值与实测均值的偏差小于2.49%,单条语音识别的正确率大于98%。探诊实验显示,探针语音交互流畅,探诊力分段显示正常,无线蓝牙通讯准确,是一种性能先进、使用便利、体验友好的新型牙周探诊工具。     

水下机器人手爪力感知系统研究

提出了一种水下机器人手爪力感知系统的组成结构,该力感知系统由一个六维力/力矩传感器和三指夹持器指端的三个指力传感器组成,本文介绍了上述两种传感器的设计和标定,并对利用该手爪系统抓取物体进行了实际测试和分析,实验结果表明;所设计的力感知系统能够实时地感知腕力和夹持力信息,可以满足机械手力控制的需要.     

基于力敏导电橡胶的新型三维力柔性触觉传感器仿真研究

针对目前触觉传感器研究中不能兼有柔韧性和多维力测量等难题,设计了一种基于力敏导电橡胶的具有整体两层非对称网状式结构的触觉传感器,通过检测导电橡胶的电阻值变化来分析三维力信息。本文介绍了该传感器的基本结构,并基于理想力敏导电橡胶的力学特性建立了三维力并行测量的数学模型,通过对该模型的求解解决了三维力及各受力点之间复杂的耦合问题。仿真实验结果表明该传感器能够实现对表面任意单点三维力、多点三维力以及三维面力信息的测量。     

模块化机器人的惯性参数辨识研究

提出了一种基于六维力／力矩传感器的模块化机器人惯性参数辨识的方法。首先，通过Newton-Euler方程建立模块化机器人的动力学方程,然后利用基座力旋量平衡原理建立辨识模型对动力学方程中的未知参数进行辨识，最后以德国AMTEC公司生产的PowerCube模块化机器人实体对这种方法进行了实验验证。     

基于Lyapunov优化的时变无线传感网路由研究

针对无线传感网应用中监测环境具有随机性和不可预测性等因素使得节点感知速率通常是时变的且某些时刻会超出链路容量的实际问题,设计了一种时变路由算法.在该算法中,将时变感知速率下的路由问题建立成以时均的网络能耗与丢弃感知数据代价的加权和最小为目标的随机优化模型,并利用Lyapunov优化技术求解该模型,进而得到一种路由策略来实时决策每条链路上的数据流量以及由于节点感知速率持续超出链路容量而不得不丢弃的数据量.进一步,讨论感知数据不被丢弃的条件,建立目标函数与感知信息最大传输时延之间的权衡关系.最后,通过仿真实验,验证了本文算法在能耗、感知数据的丢弃量及传输时延之间的均衡关系.还在不同的最大数据感知速率下,比较了本文算法与AVE算法的性能.     

模块化机器人的惯性参数辨识研究

提出了一种基于六维力/力矩传感器的模块化机器人惯性参数辨识的方法。首先,通过Newton-Euler方程建立模块化机器人的动力学方程,然后利用基座力旋量平衡原理建立辨识模型对动力学方程中的未知参数进行辨识,最后以德国AMTEC公司生产的PowerCube模块化机器人实体对这种方法进行了实验验证。     

一种基于导电橡胶的三维力柔性触觉传感器阵列机理与仿真研究

根据接触力学理论和导电橡胶的电阻应变关系,对一种基于压敏导电橡胶的三维力柔性触觉传感器阵列的传感机理进行深入的探索,并应用静电比拟法导出传感器节点间电阻与表面应力激励的关系,建立了传感器阵列表面三维力激励与输出电阻的物理模型。以此为基础对传感器输入输出特性进行了仿真,并基于仿真结果对传感器结构进行优化。仿真结果验证了该传感器结构设计的合理性。     

双层预紧式6维力传感器预紧力对精度影响分析

针对传统Stewart结构6维力传感器性能的不足,设计并研制了一种双层预紧式6维力传感器,并进行了精度分析与实验研究.首先,介绍了该6维力传感器的结构特点,基于螺旋理论建立了其数学模型以及预紧力的数学描述形式.为了提高传感器的测量精度,在分析预紧支路结构的基础上,通过增大预紧力来降低由于预紧支路结构变形产生的误差.其次,对不同预紧力下预紧支路的结构变形进行了有限元仿真.最后研制并开发了6维力传感器样机和标定系统,进行了不同预紧力情况下的标定实验.通过增大预紧力,传感器的最大Ⅰ类误差和Ⅱ类误差分别由满量程的2.73%、2.43%降低到0.41%、0.64%.实验结果表明,增大预紧力有效地降低了预紧支路变形带来的测量误差,提高了传感器的测量精度,从而验证了理论分析与仿真的正确性.     

差分进化融合混合虚拟力的有向传感器网络覆盖算法

针对感知方向可调的有向传感器网络（DSN）,为最大限度减少覆盖空洞和重叠区,从而提高有效覆盖率,提出了差分进化融合混合虚拟力的DSN覆盖算法。首先,建立有向感知模型,分析节点之间、节点与障碍物之间及节点与边界之间的混合虚拟作用力,在此基础上建立节点旋转角度与作用力之间的调整公式;然后,为弱化混合虚拟力造成的局部次优解缺陷,引入差分进化模型,将虚拟力作为进化更新的一个影响因子,节点间经过变异、交叉及选择操作来寻找最佳适度值,提高有效覆盖率。覆盖仿真实验表明,在100 m×100 m监测区域下,求得100次随机部署后经过差分进化融合混合虚拟力算法网络有效覆盖率提高了19.68%,而经过混合虚拟力算法和差分进化算法的覆盖率分别提高了10.32%和11.35%;差分进化融合混合虚拟力算法在迭代80次左右网络趋于稳定,而混合虚拟力算法和差分进化算法分别需要130次和140次左右迭代。相对于混合虚拟力算法和差分进化算法,将两者相结合的差分进化融合混合虚拟力算法的收敛速度更快,有效覆盖率提高更明显。     

仿生湿吸二维微力传感器设计与试验研究

设计了一种L型的二维微力传感器,该二维微力传感器采用悬臂梁式结构。在弹性力学和材料力学基础上,利用Solidworks三维建模软件和ANSYS仿真软件对传感器分别进行模型建立和有限元应变分析。对该二维微力传感器的实体进行标定,得出了力和输出电压之间的关系。然后,在设计与分析二维微力传感器的基础上,研制了二维微力传感器阵列测试系统。最后,在测试系统实施了不同预压力下的湿吸力测试试验,验证了传感器和系统的可靠性。     

Development of a touch probe based on five-dimensional force/torque transducer for coordinate measuring machine (CMM)

Systematic errors due to the pre-travel variation and the probe tip shape are irreducible to the traditional touch trigger probing systems. This paper describes the development of a probing system based on five-dimensional force/torque transducer for coordinate measuring machines. The compensation for pre-travel variation is accomplished through the five-dimensional force/torque information acquired by the integrated transducer and the stiffness matrix of the stylus. From the relationship between the obtained force/torque information and the geometrical shape equation, coordinates of the exact contact point immune from the contact error are acquired. After calibration, the combined measurement uncertainty is estimated to be less than ±0.3 μm.     

Modeling and Simulation for a Microstructure Silicon Concentrated Force Sensor

Based on the sensing mechanism of microsensor, a simulation model of a practical silicon beam resonator attached to an E-type round diaphragm and used for measuring concentrated force is established. The relationship between the basic natural frequency of the beam resonator and the concentrated force is calculated, analyzed and investigated. As a microsensor FEM is used to study some important simulation results on the vibration features of the beam resonators. Based on the differential output signals, a se...     

Fabrication of improved piezoresistive silicon cantilever probes for the atomic force microscope

This paper describes an improved design for a monolithic silicon atomic force microscope (AFM) probe using piezoresistive sensing. The probe is V shaped, with a sharp tip at the free end and two piezoresistors at the root, and is fabricated using silicon-on-insulator (SOI) starting material. The maximum sensitivity of the AFM probe is measured to be 4.0(± 0.1) × 10⁻⁷ Å⁻¹, which is larger than that of the previous parallel-arm piezoresistive AFM probe. The measured results are in reasonable agreement with the values predicted by theory. The minimum detectable force and minimum detectable deflection of the AFM probes are predicted to be 1.0 × 10⁻¹⁰ N and 0.29 Å_r.m.s., respectively, using a Wheatstone bridge arrangement biased at a voltage of ± 5 V and bandwidth of 10 Hz–1 kHz.     

Reconstructing a convex polygon from binary perspective projections

The data obtained from a binary perspective projection of a convex planar set is equivalent to the data obtained by tactile measurements using a certain kind of geometric probe composed of two line probes rotating about a common axis point. The reconstruction of a convex polygon (with V vertices) using this type of data is considered and a measurement strategy which guarantees a unique reconstruction following no more than 3V − 3 measurements is proposed. It is also shown that no strategy can achieve complete reconstruction using less than 3V − 3 measurements. Duality implies that the same reconstruction performance is achieved when probing with a composite finger probe.     

Adaptive trajectory control of microcantilever's tip utilised in atomic force microscopy-based manipulation

This article presents a hybrid distributed-parameters model and an adaptive control framework for microcantilevers utilised in atomic force microscope systems for controlled force manipulations. The model assumes a general nonlinear interaction force between the microcantilever's tip and the surface of the sample. This interaction force includes the sample's surface and probe's tip distance as well as the first and second derivatives of this force implicitly. Despite such detailed modelling of interaction force, there are a number of uncertainties including tip mass, damping coefficients and nature of the interaction force that would affect the response of the system and hence, an adaptive controller is needed to compensate for these unmodelled dynamics and uncertainties. Unlike the current practices that deal with the lumped-parameters model of the cantilever, a comprehensive distributed-parameters model based on the Euler–Bernoulli theory is considered here. An adaptive controller is then designed such that by giving a force input to the base of the microcantilever, the tip of the microcantilever can track a desired trajectory despite the flexibility of the microcantilever and aforementioned uncertainties. Extensive simulation results are provided to illustrate that the microcantilever's tip can asymptotically follow a harmonic trajectory even for a system with higher modes of vibration when it is designed based on single-mode model.     

基于状态反馈的LQG半主动悬架控制策略研究

随着我国智能电网的建设以及电力市场的逐步推行,传统的集中式大电网供电模式已经无法满足当今社会对电力的需求,分布式电源的引入就成为了未来电网发展的一个新趋势。分布式发电技术的引入不仅可以解决集中式发电投资大、建设周期长、调节不灵活及事故范围大等弊端,还能有效地解决全世界所面临的能源危机和环境污染等问题。由于分布式电源的引入,配电网中将会出现很多新的节点类型,处理这些节点时如果采用传统的潮流算法往往难以达到预期的效果,而潮流计算是开展配电网其它研究工作的基础,因此,研究含分布式电源的配电网潮流计算显得尤为重要。本文详细论述了分布式发电的意义以及国内外对于含分布式电源的配电网潮流算法的研究现状。     

一种三维柔性力传感单元的设计与实验

设计一种敏感单元为正四面体结构的三维柔性力传感器,对传感器进行受力分析,建立传感器单元受力的数学模型,利用有限元仿真验证上述分析过程的合理性,并通过试验系统对传感器进行标定和验证,测试结果利用BP神经网络进行解耦,结果表明该传感器能够实现0~11 N量程的三维力检测.     

Design of a slave arm of a surgical robot system to estimate the contact force at the tip of the employed instruments

Acquisition of the contact force at the instrument tip can enable better performance, e.g. transparency of the haptic feedback in the surgical robot systems. It is, however, difficult to measure the contact force directly due to technical limitations in attaching sensors to the tip of the instruments. This paper proposes a method to estimate the forces by installing the sensors away from the instrument tip. The proposed method employs specially designed mechanical parts of the slave robot, i.e. a slider cover plate for the z-axis translational force along the insertion direction, and docking clamps for the rotational pivot torques around the fulcrum point. Strain gauges are attached to specially designed places with enhancing shapes. The simulation results of the force estimation are presented to confirm the strain concentration area. The proposed method is validated with quantitative experimental results. Calibrated weights are determined upon the comparison of the strain value with a calibrated 6-axis force/torque sensor. The percentage error in the force calibration is about 5~8% calculated by the root mean square error (RMSE) of force-sensing performance. In addition, it can be computed by considering only the bending phase of each sensor although the hysteresis is observed from the calibration graph.     

Active probing based Internet service fault management in uncertain and noisy environment

In Internet service fault management based on active probing, uncertainty and noises will affect service fault management. In order to reduce the impact, challenges of Internet service fault management are analyzed in this paper. Bipartite Bayesian network is chosen to model the dependency relationship between faults and probes, binary symmetric channel is chosen to model noises, and a service fault management approach using active probing is proposed for such an environment. This approach is composed of two phases： fault detection and fault diagnosis. In first phase, we propose a greedy approximation probe selection algorithm （GAPSA）, which selects a minimal set of probes while remaining a high probability of fault detection. In second phase, we propose a fault diagnosis probe selection algorithm （FDPSA）, which selects probes to obtain more system information based on the symptoms observed in previous phase. To deal with dynamic fault set caused by fault recovery mechanism, we propose a hypothesis inference algorithm based on fault persistent time statistic （FPTS）. Simulation results prove the validity and efficiency of our approach.