摘要
现有灵活性指标——方向可操作度在规划过程中往往会出现条件数较大的情况,不利于控制。针对这一问题,提出基于条件数约束的方向可操作度这一新指标,分析该指标的偏导随条件数增大的变化情况。当条件数较小时,指标主要受方向可操作度的影响;条件数不断增大时,方向可操作度对指标的影响逐渐削弱,条件数对指标的影响不断增大。通过优化侧重点的改变,该指标能使优化结果的条件数小于任务要求的最大条件数的同时最大限度地保留方向可操作度。平面3R、BUAA-RR机器人的数值仿真和平面3R机器人的试验研究证明新指标的优越性。此外,将该指标应用于冗余度机器人的容错操作这一特殊领域,它可以使机器人在运动中任何时刻重构的新机械臂在任务方向上具有较高的操作能力,并且能够保证条件数较小,避免奇异情况的发生。
There is often such a situation that the condition number of the optimization results based on the directional manipulability is very large,which is not conductive for control.To solve this problem,a new dexterity index-directional manipulability constrained by the condition number is proposed.The changing pattern of the partial derivative of this index with the increase of the condition number is analyzed.When the condition number is small,the index is mainly influenced by the directional manipulability.While the condition number increases,the impact of the directional manipulability on the index declines,and the impact of the condition number increases.Through changing the partial derivative,the condition number of the optimization results based on this index is less than the maximum of the task requirements.Moreover,the directional manipulability can be retained to maximum.The simulation researches for planar 3R and BUAA-RR robot and the experiment research for planar 3R manipulator demonstrate the superiority of this new index.Besides,this new index is used for tolerant performance of redundant robots.When one robot’s joint fails at any moment during the task,the reduced robot based on this new index has a good manipulability on the task direction.A small condition number of the reduced robot also can be assured,which is benefit for singularity avoidance.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2010年第23期8-15,共8页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(50775002)
关键词
可操作度
运动灵活性
容错性能
冗余度机器人
Manipulability Dexterity Fault tolerant performance Redundant manipulator
