棘突间撑开器Rocker治疗腰椎间盘突出

目的探讨棘突间撑开器Rocker治疗腰椎间盘突出的临床效果。方法选取腰椎间盘突出患者32例作为研究对象,对其临床资料进行回顾性分析。所有患者均采用棘突间撑开器Rocker治疗,探讨其临床效果。结果术前ODI评分为(70.61±13.52)分,最后1次随访为(21.58±3.04)分,对比差异有统计学意义(P<0.05);术前VAS评分(9.03±2.17)分,最后1次随访为(3.04±0.76)分,对比差异有统计学意义(P<0.05)。结论对腰椎间盘突出患者采用棘突间撑开器Rocker治疗临床效果明显,可显著减轻患者疼痛,改善功能障碍,安全可靠,有推广价值。

Calculation on the pitch angle of rocker of a rocker lunar rover in uneven terrain and path planning

For the concerted motion of rocker lunar rover, the pitch angle of rocker of a rocker lunar rover in uneven terrain must be calculated. According to the character of passive shape-shifting adaptive suspension of rocker lunar rover, the model of rocker lunar rover and the model of terrain were both simplified. The pitch angle of rocker was calculated using forward solving, reverse solving and the method of offsetting the curve of terrain respectively. Because of the banishment of the nonlinearity of equation sets of calculation by reverse solving, the calculation of the pitch angle based on reverse solving was programmed by means of MATLAB. Simulations were carried out by means of ADAMS. The result verified the validity of the calculation based on reverse solving. It provides the theoretical foundation for motion planning and path planning of rocker lunar rover. As applications of the calculation of pitch angle of rocker, the multi-attribute decision making of path based on the concerted motion planning and the predictive control on lunar rover based on the Markov prediction model were introduced.

Mobile platform of rocker-type coal mine rescue robot

After a coal mine disaster,especially a gas and coal dust explosion,the space-restricted and unstructured underground terrain and explosive gas require coal mine rescue robots with good obstacle-surmounting performance and explosion-proof capability. For this type of environment,we designed a mobile platform for a rocker-type coal mine rescue robot with four independent drive wheels.The composition and operational principles of the mobile platform are introduced,we discuss the flameproof design of the rocker assembly,as well as the operational principles and mechanical structure of the bevel gear differential and the main parameters are provided.Motion simulation of the differential function and condition of the robot running on virtual,uneven terrain is carried out with ADAMS.The simulation results show that the differential device can maintain the main body of the robot at an average angle between two rockers.The robot model has good operating performance.Experiments on terrain adaptability and surmounting obstacle performance of the robot prototype have been carried out.The results indicate that the prototype has good terrain adaptability and strong obstacle-surmounting performance.

Kinematic Modeling and Characteristic Analysis of Eccentric Conjugate Non-circular Gear & Crank-Rocker & Gears Train Weft Insertion Mechanism

A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's weft insertion mechanism as well as reduce the manufacturing difficulty. Meanwhile, based on the working principle of this mechanism, kinematical mathematic models of this mechanism were established and an aided analysis and simulation software was compiled. The influences of eccentricity ratio, deformation coefficient, and other important parameters on the kinematics characteristics of this mechanism were analyzed by using the software. A group of preferable parameters which could meet the requirements of weft insertion technology were obtained by means of human-computer interactive optimization method. The maximum velocity, maximum acceleration, and variation of acceleration of this mechanism are smaller than those of the conjugate cam weft insertion mechanism applied on TT96 rapier loom under the conditions of the same unilateral total stroke of rapier head and the same rotary speed of loom spindle; meanwhile the other demands of weaving technology can be met by this novel weft insertion mechanism.

棘突间撑开器Rocker治疗腰椎间盘突出临床分析

目的探讨棘突间撑开器Rocker治疗腰椎间盘突出的临床效果。方法回顾性分析32例腰椎间盘突出患者的临床资料,探讨其临床效果。结果术前Osewstry功能障碍指数(ODI)评分为(70.61±13.52)分,最后1次随访为(21.58±3.04)分,对比差异有统计学意义(P<0.05);术前疼痛视觉模拟评分(VAS)评分(9.03±2.17)分,最后1次随访为(3.04±0.76)分,对比差异有统计学意义(P<0.05)。结论对腰椎间盘突出患者采用棘突间撑开器Rocker治疗临床效果明显,可显著减轻患者疼痛,改善功能障碍,安全可靠,有推广价值。

NOVEL METHOD OF REALIZING THE OPTIMAL TRANSMISSION OF THE CRANK-AND-ROCKERMECHANISM DESIGN

A novel method of realizing the optimal transmission of the crank-and-rockermechanism is presented. The optimal combination design is made by finding the related optimaltransmission parameters. The diagram of the optimal transmission is drawn. In the diagram, therelation among mini-mum transmission angle, the coefficient of travel speed variation, theoscillating angle of the rocker and the length of the bars is shown, concisely, conveniently anddirectly. The method possesses the main characteristic. That it is to achieve the optimaltransmission parameters under the transmission angle by directly choosing in the diagram, accordingto the given requirements. The characteristics of the mechanical transmission can be improved togain the optimal transmission effect by the method. Especially, the method is simple and convenientin practical use.

AK Rocker 200专用多媒体座椅

总是在家里的沙发或是地毯上玩游戏，看电影，生活虽然惬意，但难免千篇一律，用AK Rocker 200专用多媒体座椅给屁股和后背换个感觉怎么样？

DEVELOPMENT AND VIBRATION ANALYSIS OF CERAMIC ROCKER ARM

A ceramic rocker arm is proposed. Test for ICE performance and numerical analysis ofvalve system were earried out. The results show that ceramic rocker arm can replace ordinarysteel ones and meet the requiements of ICE practical operation, and reduce both the wear be-tween contact surfaee and the vibration of valve system.

FULLY NONLINEAR CALCULATION OF 2－D WATER WAVE GENERATED BY ROCKER FLAP WAVEMAKER

The BEM combined with the time-stepping scheme is employed in the fully nonlinear numerical calculation of 2-D free surface flow generated by large amplitude oscillation of rocker flap wavemaker. Special consideration is paid on the compatibility of free surface and body surface conditions at the intersection point. In the case study of weakly nonlinear regular wave, the comparison of elevations and hydrodynamic moments acting on the flap from the fully nonlinear calculation,second-order calculation in frequency domain and linear calculation in time domain is made, and the agreement indicates the feasibility of the numerical approach of the fully nonlinear calculation.

The interaction effects of rocker angle and apex location in rocker shoe design on foot biomechanics and Achilles tendon loading

The influences of rocker shoes on foot biomechanics were controversial because the interaction between two design factors—rocker angle and apex location,was usually omitted.This study investigated the interaction effects of rocker angle and apex location on plantar foot pressure,metatarsophalangeal/ankle angle,and Achilles tendon force during walking.Ten participants performed walking trials under six rocker shoe conditions:2 rocker angles(mild and severe)×3 apex locations(distal,standard,and proximal),wherein the plantar foot pressure was measured and the movement data were processed by musculoskeletal modeling to report joint angle and Achilles tendon force.A two-way ANOVA repeated measures was used for statistics.Significant interaction effects were reported in examinations of forefoot pressure,midfoot pressure,and metatarsophalangeal dorsiflexion.The standard apex significantly reduced peak forefoot and midfoot pressures(p=0.008–0.034,Hedges'g=0.75–0.84),which was further decreased by a severe rocker angle(p=0.006,Hedges'g=0.51–0.81).Moving the apex proximally reduced Achilles tendon forces(p<0.001,Hedges'g=0.80)and facilitated both metatarsophalangeal dorsiflexion and ankle plantarflexion during push-off(p=0.003–0.006,Hedges'g=0.03–0.82).Rocker angle seemed to have fewer effects on ankle joint angle and Achilles tendon force.We concluded that apex location was likely the dominant design factor of the rocker sole in influencing foot biomechanics,yet its interactions with rocker angle should be considered.The configuration of the two features could be varied to possess different therapeutic merits and adapt to specific application purposes.

ZG20SiMn铸钢摇臂壳体铸造过程数值仿真及工艺优化

摇臂壳体是采煤机的重要组成部件,具有多级壁厚、变截面等异形特征。为提高采煤机摇臂壳体铸造质量,解决因铸造工艺不成熟导致的缩松、缩孔等缺陷问题。以MG325型采煤机摇臂壳体为研究对象,设计顶注式和底注式两种铸造工艺方案,采用ProCAST软件探究不同浇注工艺方案下摇臂壳体铸件充型及凝固过程,分析铸件温度场、凝固场及缩松、缩孔铸造缺陷位置。基于Niyama判据和应力场分布对底注式铸造工艺方案进行优化。结果表明:优化后摇臂壳体铸件在凝固冷却过程中保持温度梯度递增,促进铸件实现顺序凝固,铸件缺陷率明显降低且充型效果更佳,缩孔体积仅占摇臂壳体体积的0.0049%,电机孔薄壁端面应力优化量为38.47%,输出端孔处应力优化量达到91.08%。本文研究成果为采煤机摇臂壳体的铸造工艺提供了理论基础和数据支撑。

曳引摇枝式板栗落果装置设计与试验

针对当前丘陵山地板栗采摘困难、人工收获工作强度大、采收效率低等问题,设计了一种由柔性钢丝绳曳引振动的小型摇枝式板栗落果装置。建立板栗果实-果枝单摆动力学模型,分析果实脱落条件,得到板栗果实振动脱落切向加速度为285.36 m/s~2,得出影响板栗果实脱落的主要因素为果枝振动频率、振幅、振动时间;进行板栗果枝振动特性试验,用Default Shaker液压振动台以0~30 Hz扫频方式确定垂直方向上板栗果枝共振频率,并在频率7~15 Hz段进行驻频试验,得出振动落果较优频率为10~12 Hz。根据果枝振动试验结果,利用ADAMS软件对摇振机构进行仿真,结果表明,摇杆振幅大于95 mm时,果枝末端加速度可满足板栗果振动脱落的加速度条件,确定了落果装置参数设计的合理性。设计了三因素三水平正交试验,试验结果表明,板栗落果最佳作业参数组合为摇振频率11 Hz、振幅135 mm、摇振时间30 s,此时板栗落果率为91.9%,树皮损伤率为8.8%,满足农业机械推广鉴定标准中树皮损伤标准。

发动机摇臂断裂原因分析

材料为QT600-3球墨铸铁的摇臂在发动机试车过程中断裂。对断裂的摇臂进行了断口的宏观和微观检验及能谱分析、化学成分分析、硬度检测和金相检验。结果表明:摇臂中有疏松和大面积夹渣,破坏了基体的连续性,并产生局部应力集中,从而导致裂纹萌生和扩展及摇臂断裂。此外,组织的球化不良也在一定程度上促进了摇臂的脆性断裂。

基于曲柄摇杆机构的仿生海扁虫水下机器人

针对现阶段MPF波动推进模式仿生机器人在体积、灵活度、运动性能等方面研究较少的问题,设计出了一种仿生海扁虫水下机器人。该机器人使用了一种无急回特性的曲柄摇杆机构作为动力传输零件,通过可传动柔性骨架实现动力的传输,带动鳍条往复摆动,形成稳定的波形推动机器人前进。进一步,通过对曲柄摇杆机构的理论计算和尺寸设计得出实际模型,运用SolidWorks Motion运动仿真进行无急回特性的验证。最后,通过3D打印件等材料制作仿生海扁虫机器人样机,进行水下运动试验,以此验证该设计可行性,在有效减小机器人体积和自身质量的同时,具有更佳的运动性能。

打包采棉机打包机构关键部件轻量化设计

为进一步改善打包采棉机打包机构的工作性能,以联合生产的4MZD-6型打包采棉机打包机构的关键部件摇臂组件为研究对象,结合尺寸优化和拓扑优化对摇臂组件进行轻量化设计,对优化前后的静动态特性进行对比分析。结果表明,摇臂组件质量减少9.46%,总质量减少23.6kg;优化后摇臂组件最大变形量基本不变,最大等效应力降低13.34MPa,固有频率有所增加,摇臂组件静动态特性得到进一步改善。实际工程应用证明了轻量化设计结果的有效性与可行性,可为打包采棉机其他结构或其他农业机械的轻量化设计提供方法指导。

智能手指关节功能康复训练器创新结构设计

因运动、年龄老化等因素导致手指功能损伤患者数量不断增加。针对这类人群进行手指康复器的设计,与传统康复产品相比,具有控制简单、方便、成本相对较低特点。通过分析仿手指运动的自由度,建立了曲柄摇杆机构,可以应用于手指康复器的结构设计;以主要机械构件和手指关节转动角度为参考因素,得出了机构的运动轨迹,在此基础上,得到各机械构件的合理尺寸,从而完成对机械构件的结构设计。通过模拟手指拉伸、弯曲来实现手指的康复功能。通过分析运动的角位移、角速度使得所得的机构更加符合手指的合理运动范围。运动仿真实验表明,该机构能带动手指在一定角度范围进行弯曲拉伸运动,可以满足手指损伤患者的康复训练需求。

摇臂连杆加工工艺与钻专夹设计

文章根据摇臂连杆的结构特点和技术要求,制订了该零件的机械加工工艺规程;在对定位装置、夹具装置及夹具体进行分析的基础上,设计并制造了用于第六道工序Φ35孔的钻孔专用夹具。应用结果表明,该夹具做到了加工精度保证、设计方案合理、结构简单实用,能有效提高摇臂连杆的加工质量及效率。

火炮摇架焊缝缺陷智能分类

针对火炮摇架结构复杂,焊缝内部缺陷检测效果不理想,选择对非平面物体和复杂结构体均适用的超声相控阵检测技术对摇架焊缝缺陷进行检测。将得到的超声相控阵图谱与ResNeXt网络模型相结合,实现焊缝缺陷的智能分类。将SK卷积单元引入ResNeXt网络模型,对摇架焊缝缺陷进行定性分析。改进后的网络模型比原ResNeXt网络的分类准确率提升5.5%,最终达到98.2%。

三指机器人手爪设计与抓取研究

传统的多指仿人灵巧手虽然已实现较高的灵巧性与仿人性,但存在设计制作繁琐或价格昂贵以及手指末端抓力偏弱的弊端。而三指机械手作为一种简化形式一般又存在灵巧性不高的问题。针对以上弊端设计了一款基于滑块-摇杆机构的三指机器人手爪。将该结构直接类比人手所设计的手指关节能够实现中节指骨与远节指骨的耦合运动,且指尖力会随手指弯曲程度的增加而增大,有利于对细小目标物进行指尖捏取;采取与传统偏航-俯仰型不同的翻滚-俯仰型掌指结构,在增加了沿掌根关节的旋转自由度的同时尽可能地丰富了手爪的抓取姿态,使其能够适应更多的目标物,增加了灵巧性。在MATLAB中建立手指运动学模型并求得手指末端工作空间。经由实验验证得出该手爪具备较大的抓取力与丰富的抓取姿态。

振动式大葱分苗装置设计与试验

为了解决大葱秧苗移栽机需人工分苗的问题设计了一种振动式大葱分苗装置,原理是利用斜抛运动的原理,通过曲柄摇杆机构施加一个振动,将堆叠的大葱秧苗分离开来。首先,分析大葱秧苗状态和运动,确定了锯齿板高为10.6mm、长为21.2mm,曲柄半径为13.4mm;其次,对大葱秧苗进行运动仿真,得到不同因素对分苗效果的影响范围;最后,以分苗率为评价指标,以电机转速、摇杆长度、单次投苗数量为试验因素进行三因素三水平的正交试验,确定较优的参数组合。用Design-Expert软件分析得到:在连杆长度为373.943mm、单次投苗数量为15棵、电机转速为368.027r/min时,分苗率达到最佳为78.20%,满足工作要求。