为满足移动机械臂高精度、低抖动的作业需求,提出一种基于修正非对称组合正弦函数(modified asymmetry combined sine function,简称MACSF)的振动抑制轨迹规划方法。首先,针对传统非对称组合正弦函数(asymmetry combined sine function...为满足移动机械臂高精度、低抖动的作业需求,提出一种基于修正非对称组合正弦函数(modified asymmetry combined sine function,简称MACSF)的振动抑制轨迹规划方法。首先,针对传统非对称组合正弦函数(asymmetry combined sine function,简称ACSF)存在加速度突变、启停阶段不稳定等问题,以驱动函数加加速度连续平滑为目标,采用改进型组合正弦函数设计加加速度时间窗口中的加速阶段和减速阶段,以降低移动机械臂的关节力矩波动;其次,通过叠加组合方法求出满足约束条件的通用型驱动函数;最后,基于机器人操作系统(robot operating system,简称ROS)搭建移动机械臂抑振算法验证平台,并使用该平台在样机场景下进行了一系列实验验证。结果表明,MACSF方法能够有效抑制移动机械臂的瞬态振动和残余振动(动态作业过程中振幅优于1 mm),从而验证了该方法的有效性和实用性。展开更多
This paper investigates adaptive tracking control for mobile manipulators with stochastic disturbances and parametric uncertainties. Based on an appropriate reduced dynamic model and an adaptive law, a controller, whi...This paper investigates adaptive tracking control for mobile manipulators with stochastic disturbances and parametric uncertainties. Based on an appropriate reduced dynamic model and an adaptive law, a controller, which is provided by incorporating stochastic control theory with related adaptive technique, overcomes the problem of over-parametrization. It is shown that the designed state-feedback controllers can guarantee that the mean square of the tracking errors can be made arbitrarily small by choosing suitable design parameters. Simulation studies on the control of 2-DOF mobile manipulator shows the effectiveness of the proposed scheme.展开更多
With good mobility and flexibility,mobile manipulators have shown broad applications in construction scenarios.Base position(BP)planning,which refers to the robot autonomously determining its working station in the en...With good mobility and flexibility,mobile manipulators have shown broad applications in construction scenarios.Base position(BP)planning,which refers to the robot autonomously determining its working station in the environment,is an important technique for mobile manipulators when performing the construction assembly task,especially in a large-scale construction environment.However,the BP planning process is tedious and time-consuming for a human worker to carry out.Thus,to improve the efficiency of construction assembly tasks,a novel BP planning method is proposed in this paper,which can lead to appropriate BPs and minimize the number of BPs at the same time.Firstly,the feasible BP regions are generated based on the grid division and the variable workspace of the mobile manipulator.Then,the positioning uncertainties of the mobile manipulator are considered in calculating the preferred BP areas using clustering.Lastly,a set coverage optimization model is established to obtain the minimum number of BPs using an optimization algorithm according to the greedy principle.The simulated experiment based on a 9-degree of free(DoF)mobile manipulator has been performed.The results illustrated that the time for BP planning was significantly reduced and the number of BPs was reduced by 63.41%compared to existing manual planning,which demonstrated the effectiveness of the proposed method.展开更多
This paper focuses on the problem of modeling and finite-time tracking control for mobile manipulators with affine and holonomic constraints. A reduced dynamic model is obtained by appropriately processing anne and ho...This paper focuses on the problem of modeling and finite-time tracking control for mobile manipulators with affine and holonomic constraints. A reduced dynamic model is obtained by appropriately processing anne and holonomic constraints, respectively. Then finite-time tracking controllers are designed to ensure that output tracking errors of closed-loop system converge to zero in finite time while the constraint force remains bounded. Finally, detailed simulation results are provided to confirm the effectiveness of the control strategy.展开更多
Adaptive motion/force tracking control is considered for a class of mobile manipulators with affine constraints and under-actuated joints in the presence of uncertainties in this paper. Dynamic equation of mobile mani...Adaptive motion/force tracking control is considered for a class of mobile manipulators with affine constraints and under-actuated joints in the presence of uncertainties in this paper. Dynamic equation of mobile manipulator is transformed into a controllable form based on dynamic coupling technique. In view of the asymptotic tracking idea and adaptive theory, adaptive controllers are proposed to achieve the desired control objective. Detailed simulation results confirm the validity of the control strategy.展开更多
The cooperative motion planning of nonholonomic wheeled mobile manipulators （WMM） with kinematic redundaney in the constrained workspace was studied. A trajectory planning method combining the probabilistic planning...The cooperative motion planning of nonholonomic wheeled mobile manipulators （WMM） with kinematic redundaney in the constrained workspace was studied. A trajectory planning method combining the probabilistic planning and the solving of inverse kinematic equations was presented. First, the probabilistie planning method was used to determine the guide configurations; then the switching objective function was defined and the path of the end-effector was constructed based on these guide configurations ; finally, the inverse kinematic equations of the WMM were solved using the gradient projection method, and the obstacle avoidance trajectory for joints of the WMM was obtained. Simulation results were given to demonstrate the effectiveness of the proposed method.展开更多
基金supported by the National Natural Science Foundation of China under Grant Nos.61603170,61573177,61773191 and 61673243the Natural Science Foundation of Shandong Province for Outstanding Young Talents in Provincial Universities under Grant No.ZR2016JL025
文摘This paper investigates adaptive tracking control for mobile manipulators with stochastic disturbances and parametric uncertainties. Based on an appropriate reduced dynamic model and an adaptive law, a controller, which is provided by incorporating stochastic control theory with related adaptive technique, overcomes the problem of over-parametrization. It is shown that the designed state-feedback controllers can guarantee that the mean square of the tracking errors can be made arbitrarily small by choosing suitable design parameters. Simulation studies on the control of 2-DOF mobile manipulator shows the effectiveness of the proposed scheme.
基金This research was supported by the National Key Research and Development Program of China(Grant No.2019YFB1310003)by the National Natural Science Foundation of China(Grant Nos.U1913603 and 61803251)by Shanghai Collaborative Innovation Center of Intelligent Manufacturing Robot Technology for Large Components(Grant No.ZXZ20211101).
文摘With good mobility and flexibility,mobile manipulators have shown broad applications in construction scenarios.Base position(BP)planning,which refers to the robot autonomously determining its working station in the environment,is an important technique for mobile manipulators when performing the construction assembly task,especially in a large-scale construction environment.However,the BP planning process is tedious and time-consuming for a human worker to carry out.Thus,to improve the efficiency of construction assembly tasks,a novel BP planning method is proposed in this paper,which can lead to appropriate BPs and minimize the number of BPs at the same time.Firstly,the feasible BP regions are generated based on the grid division and the variable workspace of the mobile manipulator.Then,the positioning uncertainties of the mobile manipulator are considered in calculating the preferred BP areas using clustering.Lastly,a set coverage optimization model is established to obtain the minimum number of BPs using an optimization algorithm according to the greedy principle.The simulated experiment based on a 9-degree of free(DoF)mobile manipulator has been performed.The results illustrated that the time for BP planning was significantly reduced and the number of BPs was reduced by 63.41%compared to existing manual planning,which demonstrated the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China under Grant Nos.61273091and 61573177the Project of Taishan Scholar of Shandong Province
文摘This paper focuses on the problem of modeling and finite-time tracking control for mobile manipulators with affine and holonomic constraints. A reduced dynamic model is obtained by appropriately processing anne and holonomic constraints, respectively. Then finite-time tracking controllers are designed to ensure that output tracking errors of closed-loop system converge to zero in finite time while the constraint force remains bounded. Finally, detailed simulation results are provided to confirm the effectiveness of the control strategy.
基金supported by National Natural Science Foundation of China (Nos.61273091 and 61403228)Project of Taishan Scholar of Shandong Province of ChinaPh.D.Programs Foundation of Ministry of Education of China (No.20123705110002)
文摘Adaptive motion/force tracking control is considered for a class of mobile manipulators with affine constraints and under-actuated joints in the presence of uncertainties in this paper. Dynamic equation of mobile manipulator is transformed into a controllable form based on dynamic coupling technique. In view of the asymptotic tracking idea and adaptive theory, adaptive controllers are proposed to achieve the desired control objective. Detailed simulation results confirm the validity of the control strategy.
基金the National Natural Science Foundation of China(Grant No.60675051)the Scientific Research Foundation of Heilongjiang Province for the Feeturned Overseas Chinese Scholars
文摘The cooperative motion planning of nonholonomic wheeled mobile manipulators （WMM） with kinematic redundaney in the constrained workspace was studied. A trajectory planning method combining the probabilistic planning and the solving of inverse kinematic equations was presented. First, the probabilistie planning method was used to determine the guide configurations; then the switching objective function was defined and the path of the end-effector was constructed based on these guide configurations ; finally, the inverse kinematic equations of the WMM were solved using the gradient projection method, and the obstacle avoidance trajectory for joints of the WMM was obtained. Simulation results were given to demonstrate the effectiveness of the proposed method.
