Bionic lightweight design of limb leg units for hydraulic quadruped robots by additive manufacturing and topology optimization

Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.

BDS机载天线增益适航性分析与验证

基于航空无线电技术委员会(Radio Technical Committee for Aeronautics,RTCA)等的相关技术标准,结合卫星通信链路预算理论,给出全球导航卫星系统(Global Navigation Satellite System,GNSS)机载天线增益适航性分析的理论方法,并对北斗卫星导航系统(Beidou Navigation Satellite System,BDS)机载天线增益进行适航性分析计算。以BDS机载天线增益适航性分析结果为设计指标进行BDS B1I频段机载无源天线的验证设计与仿真。BDS机载无源天线仿真结果满足设计指标,并具有良好的低仰角增益与圆极化性能。证明了所给GNSS机载天线增益适航性分析方法的可行性与BDS机载天线增益适航性分析结果的合理性。

Design Principles of the Non-smooth Surface of Bionic Plow Moldboard

The diverse non-smooth body surfaces to reduce soil adhesion are the evolutional results for the soil animals to fit the adhesive and wet environment and can be used as a biological basis for the design of bionic plow moldboard. The model surfaces for bionic simulation should be taken from soil animal digging organs, on which the soil motion is similar to what is on the surface of moldboard. By analyzing the distribution of non-smooth units on the body surface of the ground beetle jaw and the soil moving stresses, the design principles of the bionic moldboard for the local and the whole moldboard were presented respectively. As well, the effect of soil moving speed on reducing adhesion, the dimensions relationship between soil particles and non-smooth convexes, the relationship between the enveloping surface of non-smooth convexes and the initial smooth surface of the plow body, and the convex types of the sphere coronal and the pangolin scales,etc.were discussed.

Lightweight Design and Verification of Gantry Machining Center Crossbeam Based on Structural Bionics

The lightweight and high efficiency of natural structures are the inexhaustible sources for engineering improvements. The goal of the study is to find innovative solutions for mechanical lightweight design through the application of structural bionic approaches. Giant waterlily leaf ribs and cactus stem are investigated for their optimal framework and superior performance. Their structural characteristics are extracted and used in the bio-inspired design of Lin MC6000 gantry machining center crossbeam. By mimicking analogous network structure, the bionic model is established, which has better load-carrying capacity than conventional distribution. Finite Element Method （FEM） is used for numerical simulation. Results show better specific stiffness of the bionic model, which is increased by 17.36%. Finally the scaled models are fabricated by precision casting for static and dynamic tests. The physical experiments are compared to numerical simulation. The results show that the maximum static deformation of the bionic model is reduced by about 16.22%, with 3.31% weight reduction. In addition, the first four natural frequencies are improved obviously. The structural bionic design is a valuable reference for updating conventional mechanical structures with better performance and less material consumption.

The Lightweight Design of Low RCS Pylon Based on Structural Bionics

A concept of Specific Structure Efficiency (SSE) was proposed that can be used in the lightweight effect evaluation ofstructures.The main procedures of bionic structure design were introduced systematically.The parameter relationship betweenhollow stem of plant and the minimum weight was deduced in detail.In order to improve SSE of pylons, the structural characteristicsof hollow stem were investigated and extracted.Bionic pylon was designed based on analogous biological structuralcharacteristics.Using finite element method based simulation, the displacements and stresses in the bionic pylon were comparedwith those of the conventional pylon.Results show that the SSE of bionic pylon is improved obviously.Static, dynamic andelectromagnetism tests were carried out on conventional and bionic pylons.The weight, stress, displacement and Radar CrossSection (RCS) of both pylons were measured.Experimental results illustrate that the SSE of bionic pylon is markedly improvedthat specific strength efficiency and specific stiffness efficiency of bionic pylon are increased by 52.9% and 43.6% respectively.The RCS of bionic pylon is reduced significantly.

Design of A Bionic Spudcan and Analysis of Penetration and Extraction Performances for Jack-up Platform

The mechanisms of soil structure interaction have drawn much attention in the past years in the installation and operation of jack-up platform. A bionic spudcan produced by biomimetic of egg and snail shell is proposed, and the performance of the penetration and extraction are analyzed by numerical method. The geometric contour of egg and snail shell is measured, and its mathematical model is established respectively. According to the structure of existing spudcan of jack-up platform, three kinds of typical biomimetic spudcan are designed. Furthermore, numerical analysis models of biomimetic spudcan are established respectively to study the soil structure interaction mechanism in the process of penetration and extraction, and contrastive analysis of resistance characteristics are carried out. To conclude, the results show that the biomimetic spudcan facilitates the platform installation, and it is also beneficial to the improvement of the bearing capacity of spudcan.

Porous structures of natural materials and bionic design

This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as the epidermis of apples, with SEM (Scanning Electronic Microscope) showed that natural structures’ pores can be classified into uniform pores, gradient pores and multi pores from the viewpoint of the distribution variation of pore density, size and geometry. Furthermore, an optimal design of porous bearings was for the first time developed based on the gradient configuration of natural materials. The bionic design of porous structures is predicted to be widely developed and applied in the fields of materials and mechanical engineering in the future.

Structural Bionic Design of Machine Tool Structures

A structural bionic design process is systematically presented for lightweight mechanical structures. By mimicking biological excellent structural principles, the stiffening ribs of a machining table and a moving column were redesigned for better load-bearing efficiency. Finite element method（FEM） simulation and model experiments were carried out for performance verification, which showed the increase of structural static and dynamic performance. Structural bionic offers a new solution to change conventional structures for high specific stiffness.

可持续理念下藤编家具形态仿生设计研究

目的为进一步提升产品的可持续性应用价值,提出了可持续理念下产品形态仿生设计路径,以藤家具为研究对象,探寻藤编家具的可持续设计创新。方法首先,采用文献研究与田野调查相结合的方法,梳理国内外藤编家具的设计研究现状,总结藤编家具行业的现存问题;其次,利用问卷调研法确定用户需求及仿生对象,借助AHP(层次分析法)决策分析原理选择最佳的仿生设计元素,并应用可持续设计策略对藤编家具进行设计创新;最后,采用LCA(生命周期评价)进行设计方案的可持续性评估,确定了综合水平高的方案。结论通过构建可持续理念下产品形态仿生设计路径,提出产品领域应用的可持续设计策略,并应用于藤编家具设计实践,结合用户调查和专家打分,从元素提取、方案设计和方案评估三个方面验证路径的可行性及有效性,为藤编家具的可持续创新提供新思路。

刚性扑动仿生蝠鲼鱼的设计

蝠鲼鱼通过胸鳍摆动,在低速条件下具有良好的操纵性和稳定性。对蝠鲼鱼胸鳍刚性摆动时的水动力学性能进行仿真分析,得到蝠鲼鱼胸鳍刚性扑动最佳参数,同时得到最大推进因数。在此基础上,对刚性扑动仿生蝠鲼鱼的结构和控制系统进行设计,并进行样机研制。通过仿真与样机试验对比,验证刚性扑动仿生蝠鲼鱼设计的合理性,运行效果良好。

向自然学习的设计创新方法研究——数字生物设计路径探索

本研究以向自然学习的视角,受生物皮肤变色机制启发,尝试将其原理应用于新材料的设计和制造中,以此探索设计融合生物学知识的设计创新方法。通过实验研究,成功开发出一种能够模拟生物变色原理的新材料,这种材料具有独特的色彩变化能力,可以随着环境或刺激的变化而呈现出不同的颜色,能够模拟显示三维动态色彩。本研究的意义在于打破了传统色彩设计的局限,总结出数字生物设计的技术路径,为设计学交叉学科研究提供了新的创新方法。

旋翼无人机仿生栖息机械臂设计

为满足旋翼无人机执行林区内定点监测、侦查等任务,通过对鸟类栖息过程研究及腿足仿生研究,设计一种仿生栖息机械臂。对整机进行模块化设计及运动学分析,腿部模块使用机械系统动力学自动分析(Automatic Dynamic Analysis of Mechanical Systems,ADAMS)进行运动学轨迹仿真,爪部模块使用D-H(Denavit-Hartenberg)参数法取得趾尖运动学方程,通过MATLAB仿真得到爪部模块趾尖的工作空间点云分布。制作样机搭建试验系统,分别对趾部活动范围以及整机栖息能力进行试验验证。该设计结构简单,易操控,可完成试验室阶段的栖息行为。

偕老同穴海绵启发的仿生结构吸能特性研究

目的为得到质量更轻、吸能效果更好的结构,以自然界中偕老同穴海绵复杂硅质骨针结构为仿生原型,提出一种偕老同穴海绵仿生吸能结构。方法通过有限元仿真对偕老同穴仿生结构和4种对比结构进行准静态压缩仿真,并在此基础上分析不同构型参数对海绵仿生结构吸能性能的影响。结果结果表明,偕老同穴海绵仿生结构在压缩过程中呈现二次受力平台效应,使得其吸能效果优于传统结构,同时当斜肋板位置系数Rkl为0.3时仿生结构的吸能效果最佳。随着斜肋板厚度的增大,结构的比吸能线性增加。从压溃力效率来看,当斜肋板厚度是纵横筋板厚度的1.6倍时,结构的压溃力峰值基本等于平均压溃力,结构压溃力效率达到最优,结构的整体吸能性能效果达到最优。结论本文所提出偕老同穴海绵仿生结构为高刚轻质吸能结构设计提供了参考,在吸能防护领域具有一定的应用前景。

仿人表情机器人的下颌机构设计与运动

针对目前仿人表情机器人口部运动模式单一的问题,基于人类下颌的解剖学运动机理,设计了一种新颖的多自由度仿生下颌机构.建立了仿生下颌机构的逆向运动学模型,分析了其运动模式,实现了仿生下颌机构在空间中的多自由度运动.对多自由度仿生下颌机构进行了多刚体仿真,并通过实验验证了其可行性.仿真和实验结果表明,基于逆向运动学模型,该机构可以模拟人类下颌的张合、前推、偏移3种基本运动模式,以及咀嚼、咬唇等口部复杂运动模式,弥补了现有仿人表情机器人口部运动模式受限的问题.

基于反刍类动物臼齿仿生的平面磨具形貌结构设计与性能研究

目的 提高平面研磨加工效率及加工质量。方法 提取了反刍类动物臼齿齿面形貌特征,设计了一种模块化分布式平面研磨工具,采用ABAQUS分析了无特征规则排布磨具与仿生特征排布磨具在研磨抛光过程中对工件压力分布均匀性的影响;采用Fluent分析了仿生特征排布磨具形貌结构对磨削液流动性的影响;利用3D打印技术制备了仿生特征排布磨具与无特征规则排布磨具并进行了对比实验,通过响应面分析法讨论了转速、压力、表面结构特征等因素对磨具研磨性能的影响。结果 仿真结果表明,与无特征规则排布磨具相比,在4 N研磨压力下仿生特征排布磨具具有更优的工件表面应力分布均匀性;磨削液在磨具形貌特征间隙入口的流速为2.400 m/s时,与其他特征磨具相比,仿生特征模块化排布磨具的形貌特征间隙出口平均流速提升了29.45%。实验结果表明,与无特征规则排布磨具相比,在同等工艺下,使用仿生特征模块化排布磨具研磨的铝合金试件表面粗糙度由0.301μm降至0.188μm,下降了17.94%;当研磨压力为5 N时,材料去除速率由1.44μm/min提升至1.93μm/min,提升了34.47%。结论 平面磨具的形貌结构特征设计与排布对研磨过程中的工件接触压力分布、磨削液流动性具有重要影响。与无特征规则排布磨具相比,在相同工艺条件下臼齿仿生特征模块化排布磨具能够更有效地提升加工效率及加工质量。

糖果包装的趣味化设计研究

目的探讨糖果包装的趣味化设计,为糖果的包装设计提供创新的思路,使糖果包装更生动、更有趣、更符合消费者的心理。方法从糖果包装趣味化的重要价值入手,探讨我国糖果包装现状,并从四个层面对糖果包装的趣味化设计策略展开探讨。结论趣味性的糖果包装更能迅速地抓住这消费的眼球,激发他们的好奇心,让其形成购买欲。为此,在糖果包装设计中,要从色彩的趣味化、图形元素的趣味化、仿生设计趣味化、卡通拟人化趣味化四个层面强化包装的趣味化设计,从而更好地满足用户需求。

基于仿生设计学的交叉探究——以“猪笼草拟态元素”应用于灭蚊灯设计为

在设计过程中人工智能的辅助作用日趋显著,而人工智能的广泛应用使得设计思维的研究方式得到了极大的拓展和深化。在设计思维的教育、研究和应用方面,AI智导在仿生设计领域将人工智能与设计思维相结合,帮助设计师实现更高效、精准和创新的仿生设计,突破仿生设计的瓶颈并推动该领域的发展。本文首先介绍AI智导在仿生设计中的发展历程,然后重点介绍AI智导在仿生设计中的应用研究,最后,提出AI智导在仿生设计的挑战与未来展望。

BDS/GPS双系统软件接收机实现与性能分析

在经典的MATLAB GPS软件接收机的基础上,针对快速比特跳变的BDS信号给出了捕获跟踪和解帧策略,提出了BDS/GPS双系统伪距、载波相位、多普勒和载噪比观测量提取算法,推导了双系统定位定速的迭代式。采用NSL-STEREO射频前端采集实际的BDS B1和GPS L1双系统数字中频信号,设计了楼顶静态和动态实验,比较分析了实际场景下BDS/GPS双系统及各单系统的定位轨迹、定位定速误差和精度因子,验证了接收机性能并得到系统差异结论。

骨组织工程中传统与仿生支架结构设计的差异

背景:多孔支架作为新骨生长的临时基质在骨修复过程中起着关键作用,其中多孔支架的结构设计是骨修复过程中的研究重点。目的:综述传统支架(规则、均匀的支架)和仿生支架(不规则、不均匀的支架)在骨组织工程研究领域的应用。方法:检索中国知网(CNKI)、维普、万方、Web of Science、Science Direct、PubMed、EI等数据库,选取2008年1月至2024年3月发表的文献,中文检索词为“骨组织工程,仿生支架,骨小梁,传统支架,骨修复,三周期极小曲面”,英文检索词为“bone tissue engineering,bionic scaffolds,bone trabeculae,traditional scaffolds,bone repair,TPMS”。最终纳入81篇文献进行综述。结果与结论:骨支架的结构设计是实现骨修复和骨再生的关键,骨组织工程中的支架技术已取得显著进展。传统的规则多孔支架因简单的制造流程和良好的机械性能被广泛应用,然而这类支架往往缺乏生物活性,难以模拟自然骨组织的复杂微环境,限制了其在促进细胞增殖和骨再生方面的能力。相反,仿生支架通过模拟自然骨组织的结构特征,提供了更适宜的生理微环境,促进了成骨细胞的增殖、分化及新骨的形成,为骨缺损有效治疗提供了新的思路。尽管仿生支架在理论上具有巨大的潜力,但在实际应用中仍面临诸多挑战,支架的生物相容性、生物活性及长期稳定性等因素仍需通过临床试验进行进一步验证。

基于壁虎干黏附的刚柔耦合捕获单元力学性能研究

针对空间碎片清除和非合作目标捕获等在轨作业中的空间动态捕获问题,设计了基于壁虎干黏附机制的刚柔耦合黏附捕获单元,实现冲击接触下稳定黏附附着目标面。分析了碰撞黏附过程的动态特性;搭建捕获性能测试装置并测定黏附单元碰撞/脱附力和速度等参数的关系,分析了黏附捕获—剥离的力学特性,并指导微重力环境下黏附捕获的参数设置;最终测试装置在失重飞机上完成了微重力环境下的自主黏附捕获。结果表明:基于干黏附的捕获单元能够满足空间捕获的应用需求。