一种新型微型仿生机器鱼控制系统的设计

针对ICPF（ionic conducting polymer film）驱动的微型智能仿生机器鱼进行研究.以鱼类为仿生对象,通过对鱼类游动机理的仿生学研究,设计了鱼形结构的主体框架、两自由度的胸鳍和尾鳍推进机构及基于AVR单片机的机器鱼硬件控制系统.针对微型仿生鱼运动特点,设计了直线巡游和转弯运动等运动模式及自动避障功能.最后建立了仿生机器鱼实验系统,进行了仿生机器鱼驱动性能测试和推进实验,实现了仿生机器鱼的避障功能,验证了系统设计的可行性.     

柔性仿生机器鱼的复合推进结构设计

针对目前柔性仿生机器鱼推进结构单一等问题，文章针对性地进行了柔性仿生机器鱼的复合推进结构的设计，主要包括鱼身驱动推进结构、鱼身摆动推进结构、胸鳍扑动结构以及胸鳍浮潜结构，以提高柔性仿生机器鱼的推进效率；以及通过对所设计齿轮的校核，设计一款安全可靠、用于水下监测、环境保护的柔性仿生机器鱼。     

仿生鲔科机器鱼的多机体协同推进效率优化

推进效率是水下潜器装备运行的核心问题,对机器装备的现实应用具有至关重要的影响.针对仿鲔科鱼类研制的机器鱼,根据鲔科鱼类波状运动特征,将机器鱼体离散为由鱼体、尾鳍、胸鳍等部分组成的多刚体系统,结合鱼体所受外力载荷,运用牛顿欧拉法建立了机器鱼动力学模型.基于该动力学模型,开展了以提高机器鱼的推进效率为目标的鱼体运动参数优化设计,以机器鱼的巡游效率为目标、以鱼体各机体的运动参数为优化设计变量、选用遗传算法为优化算法,进行参数匹配优化;通过优化实现了机器鱼尾鳍、鱼体及胸鳍的多机体协同,提高了机器鱼的推进效率.针对优化匹配设计结果,进一步开展了机器鱼的运动学数值模拟仿真,结果表明机器鱼的巡游速度在数值上为鱼体长度的1. 415倍时,机器鱼的推进效率最高,其值达到最大值49. 9%.     

基于UGNX的整体叶轮逆向建模与五轴编程

复杂的叶片曲面导致整体叶轮的测量、逆向再设计及数控编程非常困难.通过测量整体叶轮样品关键特征点,基于UGNX对点云进行逆向并用曲面模块生成了三维模型,应用UG/CAM中叶轮加工专用模块,实现了叶轮五轴数控编程.在利用IS&V消除干涉、过切等现象的前提下,用五轴加工中心加工出了叶轮.本方法也适合其他同类型的整体叶轮逆向、设计及五轴数控编程.     

基于OpenGL的数控铣削仿真研究

以Windows为平台,利用OpenGL的计算机仿真和动画技术,采用基于数控代码的仿真方法,设计了仿真模块,开发了在Windows系统下运行的数控铣削三维仿真加工系统,很好地实现了数控车削加工的三维仿真.     

虚拟数控铣床仿真系统的研究与开发

在研究虚拟制造技术、数控加工技术的基础上,采用Vc 程序语言开发了数控铣削过程的三维动态仿真系统.本仿真系统能够对数控加工程序进行编辑、检验和调试,实现了数控铣削加工过程的三维动态仿真,能够检测出加工中可能出现的干涉和碰撞.从而减少了用试切法检查所带来的资源浪费和设备损耗,提高了数控设备的利用率.     

基于机器视觉的数控精密磨削加工在线检测系统

针对目前数控精密磨削检测效率低的问题,构建了基于机器视觉的数控精密磨削加工在线检测系统.通过工业CCD相机在线采集被加工工件图像,经去噪、复原等预处理后,提取工件图像的轮廓曲线数据,并实时与设计轮廓曲线进行比较,得到加工轮廓误差,在此基础上,引导工作台进行自动在线补偿,实现工件轮廓精密磨削.实验结果表明,采用该系统能够有效地提高精密磨削加工检测的精度和自动化程度.     

弧面分度凸轮的实体造型及数控加工

为了将复杂的凸轮机构可视化,实时地模拟其真实的运动状态,利用空间啮合原理,建立弧面分度凸轮的轮廓曲面方程.采用模块化设计思想,基于VC 面向对象的方法及UG二次开发技术,建立弧面分度凸轮参数化设计系统,实现具有真实感的弧面分度凸轮的三维实体造型.在UG环境下进行装配、仿真与干涉检测,验证设计的合理性.UG实体造型完成后生成数控加工程序,实现对弧面分度凸轮的数控加工.     

基于UG NX的烟灰缸设计与加工模拟研究

烟灰缸属于型腔类零件曲面复杂,常规的设计与加工效率低,在UG NX的建模和加工模块下对零件的三维辅助设计和三维辅助制造,实现了对型腔类零件的数控仿真加工,最后生成的数控加工代码在经过少量修改后可输入数控机床进行相应零件的加工,极大地减少了手工编程需要的时间,提高了生产效率。在对零件模拟加工时,能及时观察出操作上的问题并及时解决,避免了在实际加工时的错误.     

基于虚拟样机技术的六自由度机械手的仿真分析

六自由度加工机械手是采用计算机控制,液压、气压传动的高精度、高效率的先进数控加工仪器.本文采用Pro/E实体建模实现了机械手的三维设计,并描述了六自由度机械手工作状态,通过ADAMS运动分析、ANSYS仿真软件进行了虚拟样机的性能分析以验证设计的合理性和可行性.     

Mechanical design and implementation of a new biomimetic robot fish

A mechanical design method of robot fish is introduced in this paper.Based on this method an antonomous 3-Dimension(3D)locomotion robot fish with two pectoral fins and a caudal fin is developed.The pectoral fin mechanism has 3 degrees of freedom(3-DOFs),which enables the robot fish to realize yawing and pitching motions by controlling two pectoral fins.And the caudal fin mechanism is designed based on fish body wave curve fitting.The forward velocity can be adjusted by changing the caudal mechanism's oscillating frequency.Finally a physical implementation of the robot fish and experimental results are given.     

基于多点约束法的减摇鳍加强结构 CAD/CAE一体化设计

针对减摇鳍加强结构设计难度大和载荷复杂的特点,提出一种CAD/CAE一体化设计和分析方法.对减摇鳍加强结构进行三维结构设计、水动力分析和结构性能评估.其中,采用多点约束法实现模拟减摇鳍加强结构与鳍座的2种非协调性单元之间的载荷传递,应用自由面格林函数法和三维线性势流理论求解船体运动响应和水动压力.通过研究关键技术,为减摇鳍加强结构设计和分析提供新的技术途径.     

The pelvic fin and girdle of Panderichthys and the origin of tetrapod locomotion

One of the most marked transformations in the vertebrate transition to land was that of fins to limbs. This transformation involved not only the generation of morphological novelties (digits, sacrum) but also a shift in locomotory dominance from the pectoral to the pelvic appendage. Despite its importance, the transformation from pelvic fin to hindlimb is the least studied and least well-documented part of this transformation, which is bracketed by the osteolepiform Eusthenopteron and the early tetrapods Ichthyostega and Acanthostega, but is not directly illuminated by any intermediate form. Panderichthys is the closest tetrapod relative currently represented by complete fossils, but its pelvic fin skeleton has not been described. Here, I present the only known articulated pelvic fin endoskeleton and associated partial pelvis of Panderichthys. The pelvic girdle is even less tetrapod-like than that of the osteolepiform Eusthenopteron, but the pelvic fin endoskeleton shares derived characteristics with basal tetrapods despite being more primitive than the pectoral fin of Panderichthys. The evolution of tetrapod locomotion appears to have passed through a stage of body-flexion propulsion, in which the pelvic fins played a relatively minor anchoring part, before the emergence of hindlimb-powered propulsion in the interval between Panderichthys and Acanthostega.     

Multimodal swimming control of a robotic fish with pectoral fins using a CPG network

The neural-based approaches inspired by biological neural mechanisms of locomotion are becoming increasingly popular in robot control.This paper investigates a systematic method to formulate a Central Pattern Generator(CPG) based control model for mul-timodal swimming of a multi-articulated robotic fish with flexible pectoral fins.A CPG network is created to yield diverse swim-ming in three dimensions by coupling a set of nonlinear neural oscillators using nearest-neighbor interactions.In particular,a sensitivity analysis of characteristic parameters and a stability proof of the CPG network are given.Through the coordinated con-trol of the joint CPG,caudal fin CPG,and pectoral fin CPG,a diversity of swimming modes are defined and successfully imple-mented.The latest results obtained demonstrate the effectiveness of the proposed method.It is also confirmed that the CPG-based swimming control exhibits better dynamic invariability in preserving rhythm than the conventional body wave method.     

The pectoral fin of Panderichthys and the origin of digits

One of the identifying characteristics of tetrapods (limbed vertebrates) is the presence of fingers and toes. Whereas the proximal part of the tetrapod limb skeleton can easily be homologized with the paired fin skeletons of sarcopterygian (lobe-finned) fish, there has been much debate about the origin of digits. Early hypotheses interpreted digits as derivatives of fin radials, but during the 1990s the idea gained acceptance that digits are evolutionary novelties without direct equivalents in fish fin skeletons. This was partly based on developmental genetic data, but also substantially on the pectoral fin skeleton of the elpistostegid (transitional fish/tetrapod) Panderichthys, which appeared to lack distal digit-like radials. Here we present a CT scan study of an undisturbed pectoral fin of Panderichthys demonstrating that the plate-like 'ulnare' of previous reconstructions is an artefact and that distal radials are in fact present. This distal portion is more tetrapod-like than that found in Tiktaalik and, in combination with new data about fin development in basal actinopterygians, sharks and lungfish, makes a strong case for fingers not being a novelty of tetrapods but derived from pre-existing distal radials present in all sarcopterygian fish.     

贵州省洞穴高原鳅属一新种

描记采于贵州省盘县保田镇一地下洞穴高原鳅属一新种,命名保田高原鳅Triplophysa baotianensis sp. nov..新种是贵州省南盘江水系的首个高原鳅发现.与贵州已记载的5种高原鳅比较,新种与北盘江水系的贞丰高原鳅性状相近,但有明显特征可区别.（1）新种胸腹鳍平展与躯体呈“十”字形,贞丰高原鳅胸腹鳍走向正常;（2）新种背鳍起点在腹鳍起点之前上方,贞丰高原鳅在腹鳍起点之后上方;（3）新种体表裸露无鳞,贞丰高原鳅体被明显细鳞;（4）新种鼻瓣发育成短须状,贞丰高原鳅鼻瓣不呈须状;（5）新种属于南盘江水系,贞丰高原鳅属于北盘江水系.     

云南省洞穴盲金线鲃一新种——额凸盲金线鲃

2015年10月,在云南省丘北县温浏乡一喀斯特洞穴因山洪爆发形成的小湖泊中,捕到1尾无眼盲金线鲃标本.经研究系一新种,以头上额前有一短粗凸起命名额凸盲金线鲃Sinocyclocheilus convexiforeheadus Li Yang et Li sp,nov.新种与透明金线鲃S. hylinus Chen et Yang（1994）、鹰喙角金线鲃S. aquihornes Li et Yang（2007）的区别是,额部凸起短粗VS棒状长角或鹰喙状长角,胸鳍不达腹鳍起点VS胸鳍超过腹鳍起点,背鳍起点在腹鳍起点之前VS背鳍起点在腹鳍起点之后.     

狭缝宽度对分离式柱肋冷却通道内传热与流动影响的数值计算

在雷诺数为8 200~52 500内分别针对宽度为1.0,1.5,2.0,2.5mm的分离式柱肋冷却通道和同类型的柱肋冷却通道进行了传热特性和流动性能的三维稳态数值计算研究.数值计算采用结合加强壁面处理的realizable k-ε模型.将计算结果进行网格独立性验证和实验验证以保证数值计算的准确性.在所研究的Re数范围内着重分析了分离式柱肋中间狭缝宽度对冷却通道内流场和局部换热特性的影响.数值计算结果表明:分离式柱肋狭缝宽度对冷却效果有很大的影响,在研究的Re数范围内,分离式柱肋存在一个最优宽度,使得冷却效果最佳.     

数字地面模型的加密与显示

介绍以航测数据重建三维地形模型,改进三次样条曲面算法用于格网加密,提出以格网为基础的地表、地物快速显示算法,实现地物造型、树木及地表纹理的三维表示。