MECHANISM DESIGN AND MOTION ANALYSIS OF A SPHERICAL MOBILE ROBOT

A new spherical mobile robot BHQ-1 is designed. The spherical robot is driven by two internally mounted motors that induce the ball to move straight and turn around on a fiat surface. A dynamic model of the robot is developed with Lagrange method and factors affecting the driving torque of two motors are analyzed. The relationship between the turning radius of the robot and the length of two links is discussed in order to optimize its mechanism design. Simulation and experimental results demonstrate the good controllability and motion performance of BHQ-1.

A reconfigurable tracked mobile robot based on four-linkage mechanism

A novel reconfigurable tracked robot based on four-link mechanism was proposed and released for the complicated terrain environment. This robot was modularly designed and developed, which is composed of one suspension and one pair of symmetrical deployed reconfigurable track modules. This robot can implement multiple locomotion configurations by changing the track configuration, and the geometric theory analysis shows that the track length keeps constant during the process of track reconfiguration. Furthermore, a parameterized geometric model of the robot was established to analyze the kinematic performance of the robot while overcoming various obstacles. To investigate the feasibility and correctness of design theory and robot scheme, an example robot was designed to climb 45° slopes and 200 mm steps, and a group of design parameters of the robot were determined. Finally, A prototype of this robot was developed, and the test results show that the robot own powerful mobility and obstacle overcoming performance, for example, running across obstacle like mantis, extending to stride over entrenchment, standing up to elevate height, and going ahead after overturn.

Design and motion analysis of reconfigurable wheel-legged mobile robot

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex terrain.The robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice versa.Each wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a leg.First,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is obtained.The results showed that the shape conversion can be better realized by increasing the friction factor of the trigger point.Next,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried out.The motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged mechanism.The parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ability.Finally,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype experiment.The results showed that the surmountable obstacle height of the robot is about3.05 times the spoke radius.The robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

Concept of Intelligent Mechanical Design for Autonomous Mobile Robots

The concept of Intelligent Mechanical Design （IMD） is presented to show how a mechanical structure can be designed to affect robot controllability, simplification and task performance. Exploring this concept produces landmarks in the territory of mechanical robot design in the form of seven design principles. The design principles, which we call the Mecha-Telligence Principles （MTP）, provide guidance on how to design mechanics for autonomous mobile robots. These principles guide us to ask the right questions when investigating issues concerning self-controllable, reliable, feasible, and compatible mechanics for autonomous mobile robots. To show how MTP can be applied in the design process we propose a novel methodology, named as Mecha-Telligence Methodology （MTM）. Mechanical design by the proposed methodology is based on preference classification of the robot specification described by interaction of the robot with its environment and the physical parameters of the robot mechatronics. After defining new terms, we investigate the feasibility of the proposed methodology to the mechanical design of an autonomous mobile sewer inspection robot. In this industrial project we show how a passive-active intelligent moving mechanism can be designed using the MTM and employed in the field.

Variable Curvature Modeling Method of Soft Continuum Robots with Constraints

The inherent compliance of continuum robots holds great promise in the fields of soft manipulation and safe human–robot interaction.This compliance reduces the risk of damage to the manipulated object and its surroundings.However,continuum robots possess theoretically infinite degrees of freedom,and this high flexibility usually leads to complex deformations when subjected to external forces and positional constraints.Describing these complex deformations is the main challenge in modeling continuum robots.In this study,we investigated a novel variable curvature modeling method for continuum robots,considering external forces and positional constraints.The robot configuration curve is described using the developed mechanical model,and then the robot is fitted to the curve.A ten-section continuum robot prototype with a length of 1 m was developed in order to validate the model.The feasibility and accuracy of the model were verified by the ability of the robot to reach target points and track complex trajectories with a load.This work was able to serve as a new perspective for the design analysis and motion control of continuum robots.

Optimum Design of Stair-Climbing Robots Using Taguchi Method

Environmental issues like pollution are major threats to human health.Many systems are developed to reduce pollution.In this paper,an optimal mobile robot design to reduce pollution in Green supply chain management system.Green supply chain management involves as similating environmentally and eco-nomically feasible solutions into the supply chain life-cycle.Smartness,advanced technologies,and advanced networks are becoming pillars of a sustainable supply chain management system.At the same time,there is much change happening in the logistics industry.They are moving towards a new logistics model.In the new model,robotic logistics has a vital role.The reasons for this change are the rapid growth of the e-commerce business and the shortage of workers.The advantages of using robotic logistics are reduction in human errors,faster delivery speed,better customer satisfaction,more safety for workers,and high workforce adaptability.A robot with rocker-bogie suspension is a six-wheeled mobile platform that has a distinctive potential to keep all wheels on the ground continuously.It has been designed to traverse rough and uneven terrain by distributing the load over its wheels equally.However,there is a limitation to achieving high-speed mobility against vertical barriers.In this research,an optimal design of product delivery wheeled robots for a sustainable supply chain system is proposed to ensure higher adaptability and maximum stability during climbing staircases.The design parameters of the proposed robot are optimized using Taguchi Method.The aim is to get a smooth trajectory of the robot’s center-of-mass.The proposed approach realizes a robot with much-improved stability which can climb over heights more than the size of the wheel(i.e.,3 times the radius of wheels).The results reveal that the modified rocker-bogie system not only increases the stair-climbing capability but also thwarts instability due to overturning of a wheel of the robot.

Design of A Novel Wheel-Legged Robot with Rim Shape Changeable Wheels

The wheel-legged hybrid structure has been utilized by ground mobile platforms in recent years to achieve good mobility on both flat surfaces and rough terrain.However,most of the wheel-legged robots only have one-directional obstacle-crossing ability.During the motion,most of the wheel-legged robots’centroid fluctuates violently,which damages the stability of the load.What’s more,many designs of the obstacle-crossing part and transformation-driving part of this structure are highly coupled,which limits its optimal performance in both aspects.This paper presents a novel wheel-legged robot with a rim-shaped changeable wheel,which has a bi-directional and smooth obstacle-crossing ability.Based on the kinematic model,the geometric parameters of the wheel structure and the design variables of the driving four-bar mechanism are optimized separately.The kinetostatics model of the mobile platform when climbing stairs is established to determine the body length and angular velocity of the driving wheels.A pro-totype is made according to the optimal parameters.Experiments show that the prototype installed with the novel transformable wheels can overcome steps with a height of 1.52 times of its wheel radius with less fluctuation of its centroid and performs good locomotion capabilities in different environments.

Motion design of a hybrid wheeled/legged robot for lunar exploration

The robot consists of a quadruped mechanism and two active dual-wheel casters possesses the advantages of wheeled and legged mechanism, and can quickly move on the relatively plane ground with the wheeled mechanism, and can walk on the extremely uneven terrain with the legged mechanism. The effectiveness of the motion design of the hybrid robot is iHustrated by simulation results.

移动机器人全覆盖路径的BINN-元胞自动机规划

为了实现机器人对工作区域的全覆盖,提出了基于生物激励神经网络-元胞自动机系统的全覆盖路径规划方法。介绍了生物激励神经网络算法的基本原理,分析了该算法在机器人陷入死区时无法逃逸的问题。基于元胞自动机系统设计了机器人逃逸机制,包括逃逸点的确定和逃逸路径的规划方法。在仿真环境下,将元胞系统逃逸机制与基本RRT、文献[10]的BINN-RRT逃逸机制进行对比,结果表明元胞系统逃逸机制的规划时间比基本RRT小2个数量级,比BINN-RRT小1个数量级,且逃逸路径短于另外两种方法,验证了元胞系统逃逸机制的有效性和优越性。基于BINN和元胞系统的全覆盖路径比BINN-RRT规划路径更加平滑,验证了全覆盖方法的优越性和有效性。

基于多弹簧片的变刚度柔性关节的设计与研究

机器人碰撞防护是必要的,人机交互安全是机器人设计的重要指标之一.本文基于双滑块和滚珠丝杆机构,提出了一种含有4弹簧片的闭环伺服可变刚度柔性关节.根据悬臂梁结合模型的非线性静力学关系,导出了关节刚度随弹簧片有效长度变化的表达式,以变刚度的动力模型为基础,设计了可编辑逻辑控制器刚度调节控制系统.在完成了变刚度关节的设计制作基础上,进行了关节的变刚度实验,验证了刚度控制系统的可靠性和刚度计算模型的正确性.该关节具有实时动态的刚度调节功能,可以满足机器人碰撞防护的安全保护需求.

一种电杆智能攀爬机器人的设计与开发

针对电杆施工检修工作效率低、安全隐患大的问题,结合四足攀爬动物的仿生学原理,设计了一种电杆智能攀爬机器人,提出了结构设计方案并对其进行基于三维模型的构建与控制系统分析.首先,结合实际的应用场景,确定攀爬机器人夹持结构、移动机构的设计方案.其次,根据分析结果进行三维模型建立,并进行主机结构的装配;移动机构由电机驱动,实现攀升、下降等运动;基于轮式夹持方式的可靠性和普适性,夹持结构采用轮式夹持方式;最后,采用模块化思想进行智能控制部分的设计.试制物理样机,验证攀爬机器人的可靠性,经测试,达到预期功能.

能耗优化下移动机器人路径规划的变约束仿真平台设计

能耗优化下移动机器人路径规划面临移动机器人数量、作业路况、电源更换等多变化约束条件情形。基于MATLAB-App Designer开发工具,结合团队前期研究成果,设计具有交互界面的能耗优化下移动机器人路径规划变约束仿真平台。该平台根据变约束要求特性,改变具有障碍的不同规模地图、移动机器人数量、移动机器人起始及目标位置等,调用嵌入的不同智能算法,仿真生成移动机器人规划路径,实时显示能量消耗和路径长度等信息,为实际情形下移动机器人路径规划提供可靠的参考价值。

网络爬虫行政、民事、刑事一体化治理路径构建研究

网络爬虫作为一项衍生于数据化时代的新兴技术在当下已然具有不可估量的积极效能,然而其中更值得给予关注的是其背后盘根错节的法律风险。在对网络爬虫的概念以及其正反层面的影响进行剖析后可发现,在实行客观违法并合主观故意的基础上,通过所爬取的数据类型映射的不同法益认定不同罪名的规制方式实然存在许多偏颇之处,因此需要通过健全行刑衔接机制、以广义授权整体外化客观行为、明晰所爬取数据法益实质归属等途径,联动行政、民事、刑事视域进行一体化治理,以创制网络爬虫治理的全新模式。

面向移动机器人大视角运动的图神经网络视觉SLAM算法

针对移动机器人在大视角运动下光照变化剧烈或遭遇纹理稀疏场景易出现特征点提取困难,极端角度下特征难以匹配导致对极几何计算误差较大问题,提出一种融合改进图神经网络的视觉SLAM算法。基于先验位置估计的特征提取网络,通过先验位置估计实现图像特征点快速均匀检测与描述,构建真实准确的特征点信息。基于图注意力机制的特征匹配网络,通过消息传递图神经网络聚合特征点信息,使用自我与联合注意力机制对前后图像帧分权重特征匹配。将特征提取与匹配图神经网络与ORB-SLAM2系统后端非线性优化、闭环修正、局部建图模块融合,提出一个完整的单目视觉GNN-SLAM系统。实验结果表明:该算法在KITTI数据集上与ORB-SLAM2算法相比,绝对轨迹误差降低37.59%,相对位姿误差降低19.67%。

船舱格子型角焊缝移动焊接机器人系统设计

针对大型船舱格子型角焊缝空间狭小,大型自动化设备与工人难以高质量完成焊接作业的现状,设计了一种可进行连贯直角角焊缝焊接的移动焊接机器人系统。该机器人由机械结构与电路控制系统组成,其中机械结构包括双轴后驱车体、可伸缩接触式传感器、机器人升降旋转复合机构、焊枪位姿调整机构;电控系统硬件包括PLC控制器、行程限位开关、步进电机与配套驱动器、直流减速电机和配套的运动状态调控板。另外,还建立了机器人在直角段角焊缝焊接过程的运动学模型,获取了该段焊缝在均分为10段后每段焊枪的伸缩速度与机器人旋转角速度的数值,为直角型角焊缝焊接的跟踪控制过程提供了PLC编程的数据基础;并基于可伸缩接触式传感器,实现了直线型角焊缝的路径跟踪。实验证明,该机器人能实现小空间直角型角焊缝与直线型角焊缝的连贯焊接,焊缝成型质量好,无焊穿、气孔、焊瘤、咬边、裂纹等不良状况。

动态SHO-ACO的焊接机器人路径规划

移动焊接机器人在户外进行路径规划时的高效性和安全性尤为重要。针对蚁群算法(ACO)信息素以总长度为单个影响因子的缺陷,加入转向次数要素,建立环境适应度函数,从而改进轨迹上信息素增值状况;针对基本蚁群收敛速度慢的问题,借鉴自私羊群算法(SHO)的空间因素,改进启发函数;针对局部最优问题,将SHO的吸引力函数融入信息素变化中再结合环境适应度函数,动态指引蚁群朝向更加优良的轨迹前行;而且针对停滞僵局问题,提出撤离行动与预警行动,确保蚂蚁探路效率;针对传统轮转方法随机性问题,提出了评判拐弯机制以在有目的选择下一节点的同时,计算路径距离方法,降低了算法的复杂程度。SHO-ACO与势场蚁群和传统蚁群算法进行仿真对比实验,结果表明,SHO-ACO在简单环境与复杂环境中均具有优越性。

一种履带式爬绳机器人的设计及分析

丘陵地区地势较为复杂,传统交通工具难以实现运输要求。基于此,设计一种履带式爬绳机器人。该机器人整体采用双绳结构,从结构上解决了机器人在绳索上运行过程中的倾斜和侧翻问题。基于连续式爬绳装置原理,设计了履带式爬绳机构,实现了爬绳机器人在绳索上的稳定运行。履带式爬绳机构采用链传动和爬绳足相结合的结构,将爬绳足安装在带耳片的链条上。完成了爬绳机器人整体的结构设计和控制系统的开发,并对爬绳机器人关键零部件和整体框架开展有限元分析,验证了爬绳机器人结构的可靠性。该履带式爬绳机器人解决了复杂地形运输问题,为丘陵地区运输等领域提供了新方案。

Analysis of the constraint relation between ground and self-adaptive mobile mechanism of a transformable wheel-track robot

To maneuver in unstructured terrains where the ground might be soft, hard, flat or rough, a transformable wheel-track robot (NEZA-I) with a self-adaptive mobile mechanism is proposed and developed. The robot consists of a control system unit, two symmetric transformable wheel-track (TWT) units, and a rear-wheel unit. The TWT unit is the main mobile mechanism for the NEZA-I robot, with the rear-wheel unit acting as an assistant mechanism. Driven only by one servomotor, each TWT unit can efficiently select between track mode and wheel mode for optimal locomotion, autonomously switching locomotion mode and track configuration with changes in the terrain. In this paper, the mechanism structure, the self-adaptive drive system, the locomotion mode and posture of the NEZA-I robot are presented, the kinematic relation of the inside parts of the TWT unit is analysed, and the mathematic model of the constraint relation between the mobile mechanism and the ground, abbreviated to "MGCR model" is set up for the NEZA-I robot to go through some typical unstructured environments. The mechanism parameters, which influence the self-adaptability of the NEZA-I robot, are found and optimized. Basic experiments show that the mobile mechanism has the self-adaptability to navigate in unstructured terrains and has superior obstacle-negotiating performance, and that the MGCR model and the analysis method of mechanism parameters are reasonable. From a mechanism point of view, it can provide an idea for research on the adaptive control of the robot.

恒定轮距的多连杆式独立悬挂系统设计

为解决全方位轮式移动机器人搭载传统悬挂装置越障行驶时,轮距变化和轮毂中心面侧倾导致机器人运动控制难度大等问题,设计了一款由平行四边形机构、偏置曲柄滑块机构和摆动摇杆机构组成的多连杆式悬挂装置。通过ADAMS软件进行了不同地形环境的动力学仿真分析与优化设计,确定了最佳连杆结构参数。实物样机试验表明,机器人越障行驶过程中的操控性能以及轮子着地性与运动精度得到提高。

面向复杂地形的高速移动机器人设计与分析

为满足地图构建、无人驾驶等先进技术的需求,建立了面向复杂地形的轮式高速移动机器人在平地、上下坡、越障等情况下的理论力学模型,完成了移动底盘的力学分析,得到了移动底盘可实现平地、上下坡、越障三种运动的理论力学条件。根据目前对高速移动底盘的需求指标,确定了高速移动机器人的各项性能参数,完成了轮系、一体化底盘及移动机器人整体的结构设计,并对受力较大及扭矩较大的关键零部件进行了有限元仿真分析及运动学仿真分析。根据平台性能需求,完成了硬件设计及电气系统的搭建。为了验证理论研究的正确性,加工了实验样机,进行了相关实验。实验结果表明,所设计的面向复杂地形的高速移动机器人可以实现较高速度运行,具有较大的负载能力,可完成平地、上下坡、越障等运动,对于不同情况的路面具有较强的适应能力。