【作者】 史成坤；

【导师】 孙汉旭；

【作者基本信息】 北京邮电大学 ， 机械电子工程， 2010， 博士

【摘要】 球形移动机器人利用球形或类球形外壳作行走装置,将驱动机构和控制模块等都安装在全封闭的外壳内,以滚动运动为主要的移动方式。特殊的构型和运动方式使得球形机器人与传统移动形式的机器人相比具有很多独特的优势。目前已有球形机器人实现了移动性能,不具备对外操作能力,无法在一些特定环境中完成复杂任务,这大大限制了球形移动机器人的发展。针对此问题,在现有球形移动机器人的基础上,提出了一种用于紧急救援的可从高空抛撒的带臂球形机器人,其融合移动机械手的特点可执行对外操作,同时加装降速缓冲机构,在某些极端无人环境中,可以借由人力或飞机从高空布撒至工作区域,进而执行搜救工作。这种机器人不仅具有球形移动机器人运动灵活的特性,更因其可伸缩臂在特殊的场合可兼做手臂及足使用,扩大了球形移动机器人的应用范围。与传统的球形机器人相比,可从高空抛投的用于紧急救援的带臂球形机器人(BYQ－4)突破了全封闭结构,机构耦合度高,兼有非完整约束和欠驱动的特点,在理论研究上具有相当大的难度,球臂耦合的模型特点为球形机器人的建模及控制提出了新的挑战；而在高空布撒的工作需求下,其保护机构的保护能力成为机器人正常工作的前提。本论文的主要研究工作如下：(1)根据救援时某些极端环境下的高空布撒需求和带臂球形机器人的对外操作要求,制定带臂球形机器人和减震缓冲装置的结构设计方案,并分析其机构性能。(2)根据带臂球形机器人的结构特点和各部分约束关系建立球臂耦合系统的运动学模型,并基于凯恩方程建立该系统的动力学模型,为进一步的实施控制策略和优化设计提供理论基础；通过分析机器人构型特点和运动特性,提出BYQ-4的性能评价指标,利用改进的遗传算法进行机器人的优化设计。(3)分析带臂球形机器人的可控性,根据机器人的结构特点,将对外操作运动简化为“球体运动”和“抓取运动”的联合运动,详细分析这两部分的运动特点和控制方式,采用运动解耦式控制方法和“时间-状态”控制方法实现机器人本体的位置跟踪和姿态控制,进而实现机械臂末端的对外操作功能。(4)深入研究关节摩擦、滑动摩擦、滚动摩阻等非线性摩擦对球形机器人运动性能的影响,并针对实际情况中的球壳不圆度问题,利用分段建模方法建立更为接近实际情况的球形机器人动力学模型；针对非理想因素的不可精确测量性和未知性,采用自适应机制矫正控制系统参数,实现稳定控制,最后通过仿真和实验结果验证了非理想条件下球体的运动特性以及自适应控制方法对于这种非理想模型的有效性。(5)对作为载体和主要运动机构的球壳进行强度分析,针对地面行走和高空布撒两种工况,设计球形机器人的保护机构——网状球壳；借用牛顿-欧拉法分析网状球壳包覆下的球形机器人的运动特性,并进行样机实验,为改进球壳设计提供理论基础和实践经验。更多还原

【Abstract】 The spherical mobile robot has a spherical shell or shell like sphere which can support the robot to walk on the ground. Both of the driving mechanism and controlling modules are fixed in the totally-enclosed spherical shell. Its primary movement is rolling on the ground. For its special construction and movement method, the spherical mobile robot has many advantages special compared with other traditional robots.At present, the spherical mobile robots with perfect performance of movement have been designed and made, but they cannot complete some complicated tasks in some special situations without the operability outside. In order to resolve these issues, a new high-altitude throwing spherical mobile robot with a telescopic manipulator used in emergency rescue has been designed firstly based on current spherical mobile robots. Integrating the advantages of robots with multi-arms and multi-feet makes this robot can complete some outside operating tasks. In the meantime, a buffer gear installed on the robot can protect the shell and the inner structures of the shperical robot while it is thrown from high altitude to the working field. This kind of robot not only achieves the flexible movement, but also enlarges the application field of spherical robots because it can do some special tasks by telescopic arm in some special situations.Compared with other traditional spherical robots, the high-altitude throwing spherical robot with telescopic manipulator used in emergency rescue, named by BYQ-4, makes a breakthrough innovation of totally-enclosed spherical shell. It has some special properties, such as high coupling rate of mechanism, nonholonomic constraint and underactuated characteristic. So it’s very difficult to set up the theoretical and control model. At the same time, on the high-altitude throwing request, the protecting ability of the buffer gear becomes the premise of robot to work normally.The following aspects are the main research work and achievements:(1) According to the application request of high-altitude throwing and outside operating in some special rescue environment, the physical design proposals are drawn up, and then theirs structure performance is analyzed. (2) According to the characteristics of mechanism and constraint relationship of different parts, the kinematic model of spherical mobile robot with telescopic manipulator is built. The dynamical model of BYQ-4 is also given based on Kane equation. These two models set up the theoretical foundation for control strategy and optimization design. The performance evaluation indexes of BYQ-4 are proposed based on the analysis of its mechanism characteristics and motion characteristics. The improved Genetic Algorithm is applied to optimize the design of the robot.(3) Based on the analysis of the controllability and the mechanism characteristics of BYQ-4, the motion of BYQ-4 operability outside is predigested to an associated movement composed of ball movement and capture motion. The movement characteristics and control mode of every motion are analyzed. The decoupled coordinating control method and time-state control method are used to track the positions and control the posture of BYQ-4 to complete the outside operating function.(4) The motion performance of BYQ-4 impacted by joint friction, sliding friction and rolling resistance is studied in the paper. As for the out of roundness of real spherical shell, the segmentation modeling method is applied to build the dynamical model. As for poor measurement precision and unknown characteristics of the non-ideal factors, the adaptive control method is also applied to rectify the system parameters to realize stable control of BYQ-4. In the end, the motion performance and the validity of the adaptive control method applied to the non-ideal model under the non-ideal situation are verified by comparing the results of simulations and experiments.(5) The intensity analysis of the spherical shell which acts as the carrier and a main part of robot is done. The protection mechanisms of netlike shell are designed for two situations, walking and falling from high position. Using the Newton-Euler method, the motion performance of the spherical robot with netlike shell is analyzed. At the same time, the prototype testing of network shell finishes, the experiment results are very valuable for the theoretical basis and practical experience of the analysis of improved design of spherical shell.更多还原