51 resultados para Hazardous occupations


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冗余度机构具有高度的灵活性和避障能力,利用冗余自由度可以改善仿人机器人手臂的运动性能。以实现人体手臂的运动特性和操作灵活性为目标,研制了一种7DOF冗余仿人机器人手臂,根据冗余手臂的机构学特点,研究了手臂的运动学和动力学性能,并在工作空间、肘部关节的自运动能力以及手臂自重引起的关节重力矩等方面与其它两种典型的冗余手臂构形进行了比较分析。

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随着科学技术的发展,移动机器人被寄予越来越高的期望,要求其具有更高的机动性、更强的环境适应及感知能力和快速反应能力。因此,研究高效的移动机构和高性能控制系统成为排爆、消防等各种地面遥操作危险作业移动机器人的共同课题。 本论文以中国科学院沈阳自动化研究所自行研发的“灵豹”反恐防暴机器人和子母消防搜救机器人(在研)为平台,对危险作业机器人的控制系统进行了较为系统的研究。 “灵豹”机器人采用轮-腿-履带复合移动机构。其轮式移动采用三轮机构,两前主动轮单独驱动,差速完成转向,后轮为万向从动脚轮,配合前轮转向,车体转向半径可实现从零到无限大。其控制系统以嵌入式控制器为核心,采用模块化方法设计构建,保证了系统体积紧凑、实时性好和可靠性高等的应用要求。 作为智能控制技术的一种,模糊控制可以对那些数学模型难以求取或无法求取的对象进行有效控制。用基于PC的可编程控制器实现模糊控制,关键在于前期处理和软件编程,因为必须充分考虑执行速度。针对实际的非完整约束三轮式移动机器人运动方向可控性差,PID控制器参数难以实现全局整定的问题,利用模糊控制器实现运动轨迹控制。 单纯用电子罗盘测量航向角作为模糊控制器输入,环境适应性较差,本文提出一种结合脚轮偏转角和罗盘航向角计算机器人角速度和航向角的算法。试验结果表明,设计的控制器能对机器人进行有效航向跟踪,能迅速缩小航向偏差,机器人转向灵活可控,且没有大的航向偏转角速度,提高了系统适应性和运动稳定性。 子母消防搜救机器人主要用于火场侦查搜救,分为子机器人和母机器人,既可单独执行任务,又可协作搜救。机器人体积小,内部空间极其有限,要求控制系统有较高的集成度,还要能耐高温、通讯可靠。火场环境一般比较复杂,尤其是在地下建筑,通讯不畅将严重影响消防搜救机器人深入到火场深处侦查。为充分保障通讯链路畅通,设计了子母机控制系统,母机和子机可互为通讯中继,有效减少通讯死角,扩大搜索范围。系统采用基于多载波调制技术的影音传输系统作为图像及语音信号的主要通信链路,采用数字电台传输指令数据。设计的通讯系统实时性好,抗干扰能力和绕射能力强。

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介绍了一种可在危险环境下作业的遥控机器人──PXJ-Ⅱ排险机器人,分析了其功能指标及结构,简述了以武器系统和传感器为主的机器人辅助系统及其实用意义。

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Rockfall is a geological evolution process involving detachment of blocks or boulders from a slope face, then their free falls, bouncing, rolling or sliding, and finally deposition near the toe of the slope. Many facts indicate that the rockfall can cause hazards to peoples, and it can be regarded as a geological hazard. A rockfall event may only involve a boulder or rock, and also several ones. When there are peoples, buildings, or other man-made establishments within the scope of rockfall trajectory, losses will be possibly induced in tenns of human lives or damages to these facilities. Researches into mechanism, kinematics, dynamics, hazard assessment, risk analysis, and mitigation measures of rockfalls are extremely necessary and important. Occurrence of rockfall is controlled by a lot of conditions, mainly including topographical, geomorphic, geological ones and triggering factors. The rockfall especially in mountainous areas, has different origins, and occurs to be frequent, unexpected, uncertain, in groups, periodic and sectional. The characterization and classification of the rockfalls not only increase knowledge about rockfall mechanism, but also can instruct mitigation of the hazards. In addition, stability of potential rockfalls have various sensitivity to different triggering factors and changes of geometrical conditions. Through theoretical analyses, laboratory experiments and field tests, the author presents some back-analysis methods for friction coefficients of sliding and rolling, and restitution coefficients. The used input data can be obtained economically and accurately in the field. Through deep studies on hazard assessment methods and analysis of factors influencing rockfall hazard, this paper presents a new assessment methodology consisting of preliminary assessment and detailed one. From the application in a 430 km long stretch of the Highway, which is located between Paksho and Nyingtri in Tibet, the methodology can be applicable for the rockfall hazard assessment in complex and difficult terrains. In addition, risk analyses along the stretch are conducted by computing the probability of encountering rockfalls and life losses resulting from rockfall impacts. Rockfall hazards may be mitigated by avoiding hazardous areas, clearness of dangerous rocks, reinforcement, obstructing the rockfalls, leading the rockfalls, warning and monitoring for rockfalls, etc. Seen from present remedial level of rockfall hazards, different mitigation measures, economical and effective buffering units, monitoring tecliniques and consciousness of environmental protection for rockfall mitigations should be further developed.