摘要
针对空间双臂机器人抓捕翻滚目标的稳定控制问题,由于目标惯性参数的不确定性以及双臂同时作用于目标存在内力挤压,已有的稳定控制方法无法有效地约束机械臂末端与目标的接触力与力矩,无法保证控制过程中抓捕点处的接触安全.为此,本文考虑被抓捕目标惯性参数不确定性与双臂内力挤压对抓捕后阶段组合体稳定控制的影响,提出了一种保证接触安全的鲁棒稳定控制方法.首先,根据目标的有界不确定性构造鲁棒正不变集,同时考虑双臂与目标接触内力的影响,利用预测控制方法在该不变集内规划控制目标运动的虚拟接触力与力矩.然后,根据目标动力学模型以及空间双臂机器人的运动约束,规划空间双臂机器人的鲁棒安全期望运动轨迹.最后,利用障碍李雅普诺夫函数构造跟踪控制器,使空间双臂机器人有效地跟踪期望轨迹,从而使得翻滚目标运动受到等效于虚拟控制律的作用,在保证接触安全的同时实现鲁棒的稳定控制.通过空间双臂机器人稳定翻滚目标的仿真算例验证了所提方法的有效性.
Due to the inaccurate inertia parameters of the captured tumbling target and the internal wrenches at the grasping points,the motion of the space robot stabilizing the tumbling target cannot be planned and controlled effectively in the post-capture phase.In the existing studies,it is risky to track the desired trajectory planned by inaccurate parameters,which cannot restrain the contact wrenches and guarantee the safety of the grasping points.In order to control the post-capture dual-arm space robot safely,a robust control scheme is proposed for the dual-arm space robot capturing a tumbling target in this paper,where the influences of the inaccurate target inertia parameters and the internal wrenches at the grasping points are considered.First,a robust invariant set is constructed considering the influences of the inaccurate target parameters and internal stress wrenches.Then,to plan a safe desired motion for the dual-arm space robot,a virtual robust control law for the captured target is developed,where the desired trajectory of the target is planned within the constructed invariant sets.By the motion constraints between the space robot and the target,a robust desired trajectory of the dual-arm space robot is obtained.A barrier Lyapunov function based constrained controller is developed to track the robust trajectory efficiently.By tracking the robust trajectory with prescribed control performance,the designed virtual control law is applied to stabilize the captured target.During the stabilization control process,the measured contact wrenches can be restrained by the proposed scheme effectively,which guarantees the safety of the grasping points and the reliability of the stabilization control.The effectiveness of the proposed scheme is validated via the digital simulations,where a non-cooperative tumbling target is stabilized by a dual-arm space robot.
作者
夏鹏程
罗建军
王明明
Xia Pengcheng;Luo Jianjun;Wang Mingming(Research&Development Institute of Northwestern Polytechnical University in Shenzhen,Shenzhen 518057,Guangdong,China;School of Astronautica,Northwestern Polytechnical University,Xi’an 710072,China)
出处
《力学学报》
EI
CAS
CSCD
北大核心
2021年第4期1138-1155,共18页
Chinese Journal of Theoretical and Applied Mechanics
基金
深圳市科技研发资金(JCYJ20190806154412671)
国家自然科学基金(61973256,61690211,61690210)资助项目。
