基于变质量系统力学理论的爬壁机器人动力学分析

一类工作在高空危险环境下的爬壁机器人,自身拖曳的电缆或携带的作业原料（如清洗液、油漆等）的质量随着作业高度和进度可能发生变化,势必会影响机器人的壁面牵引驱动能力,而牵引能力决定了机器人的运动能力和工作可靠性．基于变质量系统力学理论,将这一类爬壁机器人系统看作变质量物体．首先,针对质点动力学的两类基本问题,利用变质量牛顿力学原理建立其动力学模型;进一步针对轮式爬壁机器人,建立了非完整约束条件下的变质量系统分析动力学模型．仿真分析表明,将这一类在高空作业的爬壁机器人作为变质量物体进行动力学分析是合理和必要的,为提高其壁面工作能力和适应性提供了一种新的研究思路．     

基于DSP技术的爬壁机器人吸附控制系统设计

壁面吸附是爬壁机器人的基本功能之一,其吸附程度直接影响爬壁机器人的稳定性和移动速度;为此,设计了基于DSP技术的爬壁机器人吸附控制系统;选择爬壁机器人传感器装置,加设DSP数字信号处理器,设计爬壁机器人吸附控制器;在硬件结构的支持下,根据爬壁机器人的组成结构和工作原理,构建相应的数学模型;在该模型下,利用DSP技术计算爬壁机器人吸附力;通过爬壁机器人在壁面环境下的受力分析结果,确定爬壁机器人安全吸附条件;以吸附控制器作为执行机构,实现爬壁机器人的吸附控制;选择负压爬壁机器人作为测试样机,通过系统测试表明,在瓷砖、木板、玻璃三种壁面环境下,与两个对比系统相比,应用此次设计系统得出爬壁机器人吸附力的控制误差降低了2.04 N,倾覆风险系数降低了0.29,具有较好的吸附控制效果。     

基于ADAMS的仿壁虎爬壁机器人的运动仿真

为实现在不同环境的壁面上自由爬行,设计了应用仿壁虎微纳米粘附阵列的爬壁机器人,建立了机器人的动力学模型及足部与壁面之间的接触模型,并利用机械系统动力学软件ADAMS的仿真功能,对机器人沿垂直壁面爬行的运动特性进行了仿真.利用ADAMS的后处理模块的分析功能,重点研究了在一个运动周期内,模型整体质心的位移、电机转矩以及足部与壁面之间的接触力随时间的变化情况.仿真结果表明该仿壁虎爬壁机器人能够以约26mm/s的速度沿着垂直的壁面平稳地运动,不存在波动和偏离.这为下一步研制仿壁虎爬壁机器人的物理样机提供了理论指导,也为其他仿生机器人的研究提供了参考.     

储罐壁面爬壁机器人吸附结构设计与优化

为了解决爬壁机器人在运动过程中由于吸附力不足而产生的倾覆问题,设计了一种具有曲面自适应性的永磁爬壁机器人。该机构区别于以往的爬壁机器人,具备两个方位上的旋转自由度,能够实现永磁吸附结构实时贴合壁面,确保提供稳定可靠的吸附力。在储罐壁面工作情况下,对机器人进行静力学分析,得到其在壁面不发生下滑和倾覆的安全吸附条件,并在此基础上,利用Ansoft Maxwell软件对吸附结构进行了仿真分析和结构优化,并获得了最佳结构尺寸。     

双足爬壁机器人壁面凹过渡步态规划研究

针对腿足式爬壁机器人在壁面过渡时的步态规划问题，以一种真空吸附式双足爬壁机器人为研究对象，在步态分析的基础上，基于有限状态机建立了机器人的步态模型，进而提出了基于加权插值和BP神经网络的双足爬壁机器人壁面凹过渡在线步态规划算法，为提高机器人壁面过渡的自主控制能力奠定了基础．仿真分析和实验结果表明，该步态规划算法对于实际的机器人系统是有效的和可行的。     

爪刺式飞行爬壁机器人的仿生机理与系统设计

在深入分析自然界生物在含粉尘非结构化表面上着陆栖息和爬行仿生原理的基础上,建立了爪刺式飞行爬壁机器人的爬行动力学模型和接触―碰撞动力学模型,研究了爬壁系统的爬行动力学和机器人整机的接触―碰撞动力学行为.利用柔性碳纤维杆和柔性绳组合机构以及爪刺机构,实现爪刺对壁面的自适应抓附与脱离.完成了具有飞行和壁面爬行能力的爪刺式飞行爬壁机器人的优化设计,并开展了整机着陆栖息和爬行的实验.通过与计算结果的比较,验证了动力学模型的正确性和仿生设计的可行性.研究得到了理想爬行步态所需要的舵机驱动力曲线,且发现当尼龙绳预紧力为0.75 N时,对爬行过程中的抖振现象的减缓效果最佳.同时,还深入分析了着陆初速度、能量转换以及舵机升力对着陆栖息的影响,结果表明当着陆碰撞前速度约为0.9 m/s、俯仰角约为?10?时,机器人能正常着陆在粗糙壁面上,并且碳纤维杆的能量转换与升力的共同配合能扩大成功着陆所需的初始状态范围.     

履带式爬壁机器人力学分析及磁吸附结构优化设计

为了解决履带式爬壁机器人吸附性与机动性存在矛盾的问题,设计了一种履带行走与永磁轮吸附相结合的爬壁机器人。为防止机器人在工作壁面上发生滑移和倾覆的失稳状况,对机器人进行静力学分析,得到机器人安全吸附在壁面时永磁轮应满足的最小磁吸附力。对永磁轮进行结构参数设计,并应用COMSOL仿真软件对永磁轮进行磁场分析和结构优化。研究结果表明,优化前永磁轮的吸附力可使机器人在壁面安全吸附;优化后永磁轮的吸附力增大,质量显著减小,吸附效率提高了16.87%。     

湿吸附机理及其在仿生爬壁机器人中的应用

提出一种新的基于湿吸附机理的仿生爬壁机器人．首先讨论湿吸附模型及吸附力的控制方法,对一种 基于硫化硅橡胶（聚合物）的仿生足垫的湿吸附力进行测试,由此验证足垫与壁面间的液体薄膜对吸附力的积极影 响．然后设计一种实验研究用的轮爪式仿生爬壁机器人,并对其进行静力学分析．最后对所设计的机器人进行爬壁 试验．结果表明,液体薄膜可以有效提高足垫吸附力,所研制的湿吸附机器人可吸附于约85度的壁面,可成功爬行 于坡度约65度的玻璃壁面,一定程度上验证了湿吸附机理爬壁机器人的可行性．     

具有壁面自适应能力的磁吸附爬壁机器人设计

为解决爬壁机器人在船舶货舱清洗过程中多壁面过渡的问题,该文设计了一种具有壁面自适应能力的磁吸附爬壁机器人,其包括磁吸附机构、自适应清洗机构和行走机构。该文首先通过建立机器人壁面过渡时的力学模型,得到机器人磁吸附力的分布特点,并据此设计出一种弧形磁吸附机构。然后利用 ANSYS Maxwell 3D 软件对该机构磁吸附力的分布进行优化,以满足壁面过渡的需要;此外,还在机器人前端设计了一种自适应清洗机构,通过对该机构的结构原理进行分析和实验,验证了清洗机构也具有壁面过渡能力。最后通过模拟船舶货舱壁面的实际特点,对机器人样机进行壁面过渡综合实验,完成了机器人舱底过渡行走实验和舱顶过渡行走实验,验证了该机器人的壁面自适应和舱内行走的能力。     

一种轮足复合式爬壁机器人动力学建模与分析

针对爬壁机器人不同状态下吸附力合理值的求解问题开展研究.首先分析了一种包含闭链约束的轮足复合型移动机构,基于运动等效原则将其拆成开链机构.利用牛顿-欧拉算法对分拆后的开链机构进行动力学建模.基于动力学模型,以运动失效的临界条件为约束函数,构建爬壁机器人在不同倾角壁面上的吸附力学模型,从而获得不同状态下吸附力的合理值.仿真和实验表明基于该模型获得的吸附力参数能够保证机器人的安全吸附.因此所构建的模型是合理的,可以为爬壁机器人在不同状态下合理控制吸附力大小提供理论依据.     

Design and analysis of a wall-climbing robot for passive adaptive movement on variable-curvature metal facades

To facilitate the safe adsorption and stable motion of robots on curved metal surfaces, a wall-climbing robot with a wheeled-type mobile mechanism that can passively self-adapt to walls with different curvature is proposed. The robot is composed of two relatively independent passive adaptive mobile mechanisms and overrunning permanent magnetic adsorption devices to achieve effective fitting of the driving wheels to the wall surface and adaptive surface motion. The overall design is based on a double-hinged connection scheme and gap-type permanent magnetic adsorption. The minimum adsorption force required for the robot to achieve stable climbing motion with no risk of slipping or capsizing is determined by developing a static analysis model. The effects of air-gap size and wall thickness on the adsorption force are analyzed by means of magnetic circuit design studies and parametric simulations on the permanent magnet adsorption device, as well as design optimization of the permanent magnet device. The motion performance test of the fabricated prototype shows that the robot can achieve adaptive curvature motion with self-attitude adjustment, and has a certain load capacity, obstacle crossing capability, and good surface adaptivity.     

Mechanism Design and Mechanical Analysis of Multi-Suction Sliding Cleaning Robot Used in Glass Curtain Wall

In order to meet the needs of high-altitude glass curtain wall cleaning, a multi-suction sliding cleaning robot was designed. The sliding robot sucker, cleaning system, obstacle avoidance and rotation ability, walking circuit and mobile working principle of the cleaning robot were designed. This involved the analysis of the robot’s anti-rollover mechanics during adsorption, of robotic winds when working at height, and of anti-sliding mechanics during robot movement, in order to explore feasible ways to improve the robot’s adsorption performance. The relationship between the effective diameter D of the suction cup, the vacuum degree △ P, and the gravity G should be determined by the anti-slipping analysis. In order to ensure the safe and reliable adsorption force and the flexibility of this robot when moving on a wall, the aforementioned analyses were conducted to improve the motion performance of wall-climbing robots, which provides a good theoretical basis for design optimization and motion control of cleaning robots. The curtain wall cleaning robot has stable walking ability and can clean the wall surface effectively; therefore, it has a certain practical value.     

一种基于行星履带轮越障与混合双吸附补偿的爬壁机器人的设计与研究

针对爬壁机器人在复杂壁面工作时越障能力弱、移动迟缓和吸附力不足等问题,设计了一种基于行星履带轮越障与混合双吸附补偿的爬壁机器人,并对壁面移动和越障的性能进行研究。首先根据机器人在壁面上的运动原理,建立其力学模型,计算出沿壁面移动和越障所需的吸附力;进一步结合其受力情况,对越障过程中爬升阶段和跨越阶段的吸附力补偿模型和行...     

Application of a Perturbation Method for Realistic Dynamic Simulation of Industrial Robots

This paper presents the application of a perturbation method for the closed-loop dynamic simulation of a rigid-link manipulator with joint friction. In this method the perturbed motion of the manipulator is modelled as a first-order perturbation of the nominal manipulator motion. A non-linear finite element method is used to formulate the dynamic equations of the manipulator mechanism. In a closed-loop simulation the driving torques are generated by the control system. Friction torques at the actuator joints are introduced at the stage of perturbed dynamics. For a mathematical model of the friction torques we implemented the LuGre friction model that accounts both for the sliding and pre-sliding regime. To illustrate the method, the motion of a six-axes industrial Stäubli robot is simulated. The manipulation task implies transferring a laser spot along a straight line with a trapezoidal velocity profile. The computed trajectory tracking errors are compared with measured values, where in both cases the tip position is computed from the joint angles using a nominal kinematic robot model. It is found that a closed-loop simulation using a non-linear finite element model of this robot is very time-consuming due to the small time step of the discrete controller. Using the perturbation method with the linearised model a substantial reduction of the computer time is achieved without loss of accuracy.     

基于机器人运动模型的EKF-SLAM算法改进

针对两轮驱动机器人运动模型定向误差的累积问题,提出改进的三轮驱动机器人运动模型,对EKF-SLAM算法的一致性进行改进;该模型通过对机器人车轮线速度的解耦运算,将机器人运动过程中的旋转角速度提取出来并作为系统的控制输入之一,从而可以直接得到各个控制时间间隔内的机器人姿态角变化,很好地避免了机器人定向误差的累积;最后,基于归一化估计方差的检验标准进行实验,验证了三轮驱动机器人运动模型有效提高了EKF-SLAM算法的一致性。     

基于动力学模型的轮式移动机器人电机控制

针对移动机器人两路电机协同控制问题,提出基于动力学模型的轮式移动机器人电机控制律 （DMMC）．首先推导出质心位置不一定在几何中心的移动机器人运动学模型和动力学模型,并求解出两轮速 度与力矩之间的非线性微分方程．然后,基于两轮速度与力矩间非线性微分方程、电机电气方程和电机机电 方程,推导出移动机器人系统状态方程．最后采用极点配置得到I 型状态反馈控制律．仿真显示,DMMC 法实 现了对输入指令的零稳态误差快速响应．     

Design and analysis of a wall-climbing robot for water wall inspection of thermal power plants

Boiler water wall in thermal power plants is characterized by high-altitude detection requirements. Moreover, the existing water wall-climbing robots are characterized by low obstacle-crossing performance, deviations, and a lack of autonomous crossing pipeline function. In view of this feature, a wall-climbing robot with permanent magnet and electromagnetic hybrid adsorption wheels is proposed. The robot has the function of independent traverse according to its own structural characteristics. Furthermore, transverse movement is proposed by comparing different adsorption modes, moving and driving modes. Robot statics in upward, downward, and transverse crawling are carried out, and nonsliding mechanical and nonoverturning mechanical models are obtained. Robot's dynamics are analyzed by considering the wall movement. The finite element simulation analysis of its main stressed parts is carried out by employing ANSYS, and an optimal structural model is obtained. The gap adsorption permanent magnet model is constructed, and its parametric simulation analysis is carried out using the Ansoft Maxwell module. The influence curve of the gap on the magnetic force is then obtained. Finally, the prototype is developed according to the design model and calculation analysis, and the experimental test is carried out. The experimental results show that the robot meets the expected functions and indexes, providing a basis for the intelligent development of thermal power plants.     

Dynamic Analysis Tool for Legged Robots

The paper introduces a systematic approach for dealing with legged robot mechanism analysis. First, we briefly summarize basic mathematical tools for studying the dynamics of these multi-loop and parallel mechanisms using a unified spatial formulation which is useful for computer algorithms. The dynamic behavior analysis is based on two stages. The first one deals with establishing the equations of motion of the whole mechanism including legs tip impact effects and allowing us to solve the direct and inverse dynamic problems. The second concerns the feet–ground interaction aspect which is one of the major problem in the context of dynamic simulation for walking devices. We focus on the phenomenon of contact by introducing a general model for dynamic simulation of contacts between a walking robot and ground. This model considers a force distribution and uses an analytical form for each force depending only on the known state of the robot system. Finally, some simulation results of biped robot are given. The simulation includes all phenomena that may occur during the locomotion cycle: impact, transition from impact to contact, contact during support with static friction, transition from static to sliding friction and sliding friction.     

On the motion of a mobile robot with roller-carrying wheels

The motion equations of a robot on a horizontal surface on three roller-carrying wheels of omni directional type are derived without account of possible slippage. An exact solution of the equations is found when at the direct-current motors moving the wheels a constant voltage is supplied. The problem of minimizing the torques of electric motors is considered and steady-state motion modes are specified for which the torques of electric motors and energy expenses are minimum. The reckoning system for the robot traveled distance is described.