汽车驾驶机器人研究中的一个关键问题就是多机械手的协调控制。为了实现驾驶机器人换档机械手和油门、离合、制动机械腿的综合协调控制,最终实现对给定循环行驶工况的车速跟踪,首先建立了基于Saridis G N三级控制架构的驾驶机器人递阶...汽车驾驶机器人研究中的一个关键问题就是多机械手的协调控制。为了实现驾驶机器人换档机械手和油门、离合、制动机械腿的综合协调控制,最终实现对给定循环行驶工况的车速跟踪,首先建立了基于Saridis G N三级控制架构的驾驶机器人递阶控制模型体系结构,然后在此基础上提出了驾驶机器人多机械手协调控制方法,并设计了油门/离合器协调控制器和油门/制动切换控制器。试验结果表明,本文提出的方法能合理协调控制汽车驾驶机器人油门、制动、离合机械腿和换挡机械手,实现了车辆的平稳起步,平顺换挡以及对给定车速的跟踪。展开更多
The simultaneous placement of different types of materials including polymers,ceramics,and metals,in their desired positions could be adopted to manufacture end-use devices/apparatuses with diverse functionalities and...The simultaneous placement of different types of materials including polymers,ceramics,and metals,in their desired positions could be adopted to manufacture end-use devices/apparatuses with diverse functionalities and significantly reduce the fabrication cost and time.However,existing additive manufacturing(AM)approaches can only treat one material species at a time due to their intrinsic working mechanisms.Here we develop an AM manipulator for manufacturing a wide variety of material species,including polymers,ceramics,and metals,through a multifilament transport strategy assisted by laser power.The six-jaw manipulator contains three pairs of filament delivering/cutting systems for transporting diverse materials and a beam of tunable laser as the thermal source.The whole apparatus is integrated into a robotic manipulator to create a multifreedom manufacturing platform.With this innovation,products with multiple material species and desired complex geometries can be fabricated on demand.Furthermore,we synthesize a multimaterial(polymer/ceramic/metal)printed magnetoelectric pressure sensor that can convert applied mechanical forces to electricity and maintain efficiency even after undergoing 10000 cycles of pressure/recovery.With this multimaterial filament transport and laser manufacturing strategy,our AM manipulator exhibits promising application in the advanced manufacturing of embedded electronics,sensors,soft robotics,and customizable medical devices.展开更多
The control problem of multiple-flexible-link manipulators( MFLMs) is studied in this paper.The dynamic model of MFLM is derived and separated into two-time scale by utilizing the singular perturbation technique. The ...The control problem of multiple-flexible-link manipulators( MFLMs) is studied in this paper.The dynamic model of MFLM is derived and separated into two-time scale by utilizing the singular perturbation technique. The active disturbance rejection control( ADRC) is adopted to the slow subsystem to track a desired trajectory. The proposed ADRC structure preshapes the desired trajectory by utilizing the tracking differentiator,estimates the disturbance and internal states with an extended state observer,and guarantees a robust performance by combining a feedback controller with a feedforward term. Two types of feedback controllers are designed,proportional derivative( PD) controller and nonlinear PD( NPD) controller. For the fast subsystem,a fast stabilizing control is designed according to the standard linear quadratic regulator approach. Simulations are performed to evaluate the proposed control scheme.Results show that,compared with the traditional PD controller,the ADRC structure based control scheme has smaller overshot and shorter settling time,suppresses vibration quickly,and is robust to the maneuver speed. In general,the control scheme utilizing ADRC structure and NPD feedback controller shows better performance.展开更多
In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacle...In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacles and a manipulator was obtained according to the states of obstacles and transformed to escape velocity of the corresponding link of the manipulator.The escape velocity was introduced to the gradient projection method to obtain the joint velocity of the manipulator so as to complete the obstacle avoidance trajectory planning.A7-DOF manipulator was used in the simulation,and the results verified the effectiveness of the algorithm.展开更多
文摘汽车驾驶机器人研究中的一个关键问题就是多机械手的协调控制。为了实现驾驶机器人换档机械手和油门、离合、制动机械腿的综合协调控制,最终实现对给定循环行驶工况的车速跟踪,首先建立了基于Saridis G N三级控制架构的驾驶机器人递阶控制模型体系结构,然后在此基础上提出了驾驶机器人多机械手协调控制方法,并设计了油门/离合器协调控制器和油门/制动切换控制器。试验结果表明,本文提出的方法能合理协调控制汽车驾驶机器人油门、制动、离合机械腿和换挡机械手,实现了车辆的平稳起步,平顺换挡以及对给定车速的跟踪。
基金supported by the National Natural Science Foundation of China Aerospace Advanced Manufacturing Technology Research Joint Fund(Grant No.U2037203,2020)the Fundamental Research Funds for the Central Universities(Grant No.YCJJ202202010)+1 种基金supported by the State Key Laboratory of Materials Processing and Die&Mould Technology and Analysis and Testing Center,Huazhong University of Science and Technology。
文摘The simultaneous placement of different types of materials including polymers,ceramics,and metals,in their desired positions could be adopted to manufacture end-use devices/apparatuses with diverse functionalities and significantly reduce the fabrication cost and time.However,existing additive manufacturing(AM)approaches can only treat one material species at a time due to their intrinsic working mechanisms.Here we develop an AM manipulator for manufacturing a wide variety of material species,including polymers,ceramics,and metals,through a multifilament transport strategy assisted by laser power.The six-jaw manipulator contains three pairs of filament delivering/cutting systems for transporting diverse materials and a beam of tunable laser as the thermal source.The whole apparatus is integrated into a robotic manipulator to create a multifreedom manufacturing platform.With this innovation,products with multiple material species and desired complex geometries can be fabricated on demand.Furthermore,we synthesize a multimaterial(polymer/ceramic/metal)printed magnetoelectric pressure sensor that can convert applied mechanical forces to electricity and maintain efficiency even after undergoing 10000 cycles of pressure/recovery.With this multimaterial filament transport and laser manufacturing strategy,our AM manipulator exhibits promising application in the advanced manufacturing of embedded electronics,sensors,soft robotics,and customizable medical devices.
基金Sponsored by the China Postdoctoral Science Foundation(Grant No.2014M560255)the Open Research Fund of the State Key Laboratory of Robotics and System(HIT)(Grant No.SKLRS-2013-ZD-05)+1 种基金the Heilongjiang Postdoctoral Found(Grant No.LBH-Z14107)the Special Foundation of Heilongjiang Postdoctoral Science(Grant No.LBH-TZ1609)
文摘The control problem of multiple-flexible-link manipulators( MFLMs) is studied in this paper.The dynamic model of MFLM is derived and separated into two-time scale by utilizing the singular perturbation technique. The active disturbance rejection control( ADRC) is adopted to the slow subsystem to track a desired trajectory. The proposed ADRC structure preshapes the desired trajectory by utilizing the tracking differentiator,estimates the disturbance and internal states with an extended state observer,and guarantees a robust performance by combining a feedback controller with a feedforward term. Two types of feedback controllers are designed,proportional derivative( PD) controller and nonlinear PD( NPD) controller. For the fast subsystem,a fast stabilizing control is designed according to the standard linear quadratic regulator approach. Simulations are performed to evaluate the proposed control scheme.Results show that,compared with the traditional PD controller,the ADRC structure based control scheme has smaller overshot and shorter settling time,suppresses vibration quickly,and is robust to the maneuver speed. In general,the control scheme utilizing ADRC structure and NPD feedback controller shows better performance.
基金Supported by Ministeral Level Advanced Research Foundation(65822576)Beijing Municipal Education Commission(KM201310858004,KM201310858001)
文摘In order to overcome the shortcomings of the previous obstacle avoidance algorithms,an obstacle avoidance algorithm applicable to multiple mobile obstacles was proposed.The minimum prediction distance between obstacles and a manipulator was obtained according to the states of obstacles and transformed to escape velocity of the corresponding link of the manipulator.The escape velocity was introduced to the gradient projection method to obtain the joint velocity of the manipulator so as to complete the obstacle avoidance trajectory planning.A7-DOF manipulator was used in the simulation,and the results verified the effectiveness of the algorithm.
