Mechanisms and Robotics—Innovative Tools for Modern Machines and Equipments (I)
Editor's Note
Guest Editor
Guo Weizhong Professor
Shanghai Jiao Tong University
His research interests in innovative design of institutions and robotics, parallel robots and major equipment, etc.
He kai senior engineer
Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences
His research interests include precision manufacturing and automation, industrialspecial robots, automation for biological manufacturing, metal forming technology and equipment, etc.
Article List
2022, 11(4):3-18.
DOI: 10.12146/j.issn.2095-3135.20220224001
Abstract:
Wheel is a great invention of human beings. The wheeled mobile system has brought great convenience to humans in production and daily life. Therefore, the wheeled robot is a very important development direction. To overcome the problem of insufficient adaptability of ordinary wheels to complex terrain, many research works have been investigated including the adhesion mode between wheels and supporting surface, the wheels’ geometry, the steering mode and so on. In this paper, based on the mechanism of wheels changing sliding friction into rolling friction, this paper proposes three new wheel structures, including tri-mode transformable wheel, magnetic adhesion wheel and variable parameter omni-directional wheel, and their corresponding wheel mobility structure, which aims at the requirements of uneven terrain crossing, vertical wall climbing and ground omni-directional movement. Through the linkage mechanism, the tri-mode transformable wheel switches its geometry among round mode, claw mode and hook mode, and the bi-directional obstacle crossing of the robot is realized; Through the magnetic adhesion wheel and passive suspension with three degrees of freedom, the robot can move on the wall with all wheels attached to the surface; Through applying the spatial mechanism to adjust the roller installation angles, the direction of wheel friction can be controlled and the omni-directional driving of the robot can be realized; through prototype construction and experimental study, the feasibility of the proposed innovative designs are verified.
Wheel is a great invention of human beings. The wheeled mobile system has brought great convenience to humans in production and daily life. Therefore, the wheeled robot is a very important development direction. To overcome the problem of insufficient adaptability of ordinary wheels to complex terrain, many research works have been investigated including the adhesion mode between wheels and supporting surface, the wheels’ geometry, the steering mode and so on. In this paper, based on the mechanism of wheels changing sliding friction into rolling friction, this paper proposes three new wheel structures, including tri-mode transformable wheel, magnetic adhesion wheel and variable parameter omni-directional wheel, and their corresponding wheel mobility structure, which aims at the requirements of uneven terrain crossing, vertical wall climbing and ground omni-directional movement. Through the linkage mechanism, the tri-mode transformable wheel switches its geometry among round mode, claw mode and hook mode, and the bi-directional obstacle crossing of the robot is realized; Through the magnetic adhesion wheel and passive suspension with three degrees of freedom, the robot can move on the wall with all wheels attached to the surface; Through applying the spatial mechanism to adjust the roller installation angles, the direction of wheel friction can be controlled and the omni-directional driving of the robot can be realized; through prototype construction and experimental study, the feasibility of the proposed innovative designs are verified.
2022, 11(4):19-30.
DOI: 10.12146/j.issn.2095-3135.20211228001
Abstract:
In order to solve the difficulty of multi-wall transition in the cleaning process of ship cargo hold,a magnetic adsorption wall-climbing robot with adaptive ability to wall is designed in this paper, which includes magnetic adsorption mechanism, adaptive cleaning mechanism and walking mechanism. Firstly, a mechanical model of the robot in the process of wall transition is established to obtain the distribution characteristics of magnetic adsorption force and a magnetic adsorption mechanism is designed. Secondly, ANSYS Maxwell 3D software is used to optimize the distribution of magnetic adsorption force of the mechanism to meet the needs of wall transition. An adaptive cleaning mechanism is designed in the head of the robot, and the wall transition ability of the cleaning mechanism is verified by experiments. Finally, the robot prototype is tested according to the actual characteristics of cargo hold wall. Experiments show that the wall-climbing robot can complete the transition process between the bilge and the roof of the cargo hold, which verifies the robot’s ability to adapt to the wall and walk in the cabin.
In order to solve the difficulty of multi-wall transition in the cleaning process of ship cargo hold,a magnetic adsorption wall-climbing robot with adaptive ability to wall is designed in this paper, which includes magnetic adsorption mechanism, adaptive cleaning mechanism and walking mechanism. Firstly, a mechanical model of the robot in the process of wall transition is established to obtain the distribution characteristics of magnetic adsorption force and a magnetic adsorption mechanism is designed. Secondly, ANSYS Maxwell 3D software is used to optimize the distribution of magnetic adsorption force of the mechanism to meet the needs of wall transition. An adaptive cleaning mechanism is designed in the head of the robot, and the wall transition ability of the cleaning mechanism is verified by experiments. Finally, the robot prototype is tested according to the actual characteristics of cargo hold wall. Experiments show that the wall-climbing robot can complete the transition process between the bilge and the roof of the cargo hold, which verifies the robot’s ability to adapt to the wall and walk in the cabin.
2022, 11(4):31-43.
DOI: 10.12146/j.issn.2095-3135.20220128001
Abstract:
It is still a challenge to design a hand prosthesis with a consideration of multi- motions and light weight. In this paper, by analyzing 16 commonly-used motions of human hands, a trade-off plan between weight saving and the number of motions of a hand prosthesis is studied. We determine the functions to be implemented as a constant interlock mechanism of four fingers. An adaptive mechanism is applied for the thumb, and the symmetric series elastic actuator is used for the arching of metacarpal. With such a design, a prosthetic hand was designed just using three motors embedded in the palm, which has weight of 132.1 g and could perform 11 motions. The grasping stability and operability of the hand prosthesis were confirmed with intuitive myoelectric control based on a neural network algorithm in the subject experiments.
It is still a challenge to design a hand prosthesis with a consideration of multi- motions and light weight. In this paper, by analyzing 16 commonly-used motions of human hands, a trade-off plan between weight saving and the number of motions of a hand prosthesis is studied. We determine the functions to be implemented as a constant interlock mechanism of four fingers. An adaptive mechanism is applied for the thumb, and the symmetric series elastic actuator is used for the arching of metacarpal. With such a design, a prosthetic hand was designed just using three motors embedded in the palm, which has weight of 132.1 g and could perform 11 motions. The grasping stability and operability of the hand prosthesis were confirmed with intuitive myoelectric control based on a neural network algorithm in the subject experiments.
2022, 11(4):44-55.
DOI: 10.12146/j.issn.2095-3135.20211226001
Abstract:
Underwater bionic robots have distinct advantages such as the high efficiency, high mobility and low noise etc. In this paper, a deep reinforcement learning based method is studied to control the robotic eel. Firstly, based on the propulsion principle of active and passive bionic mechanism, a robotic eel with two active rigid bodies and two compliant bodies is designed. Secondly, the robotic eel is modeled and simulated. The data collecting and training tasks are carried out in the simulation environment using deep reinforcement learning algorithms. The neural network with better performance is selected as the control function for the robotic eel. Finally, feasibility of the design and effectiveness of the control function are verified by a prototype via real experiments.
Underwater bionic robots have distinct advantages such as the high efficiency, high mobility and low noise etc. In this paper, a deep reinforcement learning based method is studied to control the robotic eel. Firstly, based on the propulsion principle of active and passive bionic mechanism, a robotic eel with two active rigid bodies and two compliant bodies is designed. Secondly, the robotic eel is modeled and simulated. The data collecting and training tasks are carried out in the simulation environment using deep reinforcement learning algorithms. The neural network with better performance is selected as the control function for the robotic eel. Finally, feasibility of the design and effectiveness of the control function are verified by a prototype via real experiments.
2022, 11(4):56-69.
DOI: 10.12146/j.issn.2095-3135.20211221001
Abstract:
To study the human-robot collaborative assembly process of space erectable truss structure, an innovative configuration that suitable for radial fast assembly of truss modules was proposed in this work. Based on state matrix and adjacency matrix, mathematic models of assembly sequence, assembly mode and assembly process of truss structures was established firstly. Then, the human-robot capability constraints of truss assembly in space environment were analyzed. The hierarchical decomposition of assembly tasks based on dynamic operation element analysis was proposed. The process and assignment scheme of human-robot collaborative assembly tasks suitable for programming were given by using the principle of comparison and allocation. Finally, to verify the rationality and feasibility of the proposed assembly process, a ground demonstration test was carried out for the collaborative assembly of 5 m long erectable truss structure by human wearing simulated space suit and manipulator. The results showed that, the proposed scheme can provide an effective way to realize the on-orbit construction of large space facilities.
To study the human-robot collaborative assembly process of space erectable truss structure, an innovative configuration that suitable for radial fast assembly of truss modules was proposed in this work. Based on state matrix and adjacency matrix, mathematic models of assembly sequence, assembly mode and assembly process of truss structures was established firstly. Then, the human-robot capability constraints of truss assembly in space environment were analyzed. The hierarchical decomposition of assembly tasks based on dynamic operation element analysis was proposed. The process and assignment scheme of human-robot collaborative assembly tasks suitable for programming were given by using the principle of comparison and allocation. Finally, to verify the rationality and feasibility of the proposed assembly process, a ground demonstration test was carried out for the collaborative assembly of 5 m long erectable truss structure by human wearing simulated space suit and manipulator. The results showed that, the proposed scheme can provide an effective way to realize the on-orbit construction of large space facilities.
2022, 11(6):1-4.
DOI: 10.12146/j.issn.2095-3135.20220703001
Abstract:
Mechanism and robotics play a significant role in the innovation and development of machines.With the development of human production and lifestyle, mechanism will meet the major needs and focus on the research and construction of the theoretical system of behavioral mechanism. Robotics will concentrate on the construction and development of Tri-Co Robots (Coexisting-Cooperative-Cognitive) theory, technology, and engineering application systems through multidisciplinary integration. The research and development of both mechanism and robotics will make great contributions to improve the design level of national high-end equipment, independence, and controllability of national technology.
Mechanism and robotics play a significant role in the innovation and development of machines.With the development of human production and lifestyle, mechanism will meet the major needs and focus on the research and construction of the theoretical system of behavioral mechanism. Robotics will concentrate on the construction and development of Tri-Co Robots (Coexisting-Cooperative-Cognitive) theory, technology, and engineering application systems through multidisciplinary integration. The research and development of both mechanism and robotics will make great contributions to improve the design level of national high-end equipment, independence, and controllability of national technology.
2022, 11(6):5-22.
DOI: 10.12146/j.issn.2095-3135.20220224002
Abstract:
3D printing technology has been widely applied in aerospace, military, robotics and many other fields. However, some problems need to be solved, such as stacking error caused by the stair-stepping effect, anisotropy of printing parts caused by the 2.5D manufacturing principle, and time-consuming and energy consumption caused by printing and post-processing supporting structure. This paper studies the 3D printing method of rotary surface, carries out the innovative design research of multi-degree of freedom rotary 3D printing equipment, determines the printer’s structural parameters based on dimension design, and puts forward the path planning methods for curved layer printing. This paper verifies the correctness of type synthesis and dimension design of the 3D printing equipment through co-simulation and prototype experiments. Meanwhile, preliminary experimental research results show the feasibility of applying 3D printing equipment to curved layer printing from a qualitative point of view. Results of this study provide new ideas for innovative design methods of printing equipment, planning strategies for curved layer printing and related experimental research.
3D printing technology has been widely applied in aerospace, military, robotics and many other fields. However, some problems need to be solved, such as stacking error caused by the stair-stepping effect, anisotropy of printing parts caused by the 2.5D manufacturing principle, and time-consuming and energy consumption caused by printing and post-processing supporting structure. This paper studies the 3D printing method of rotary surface, carries out the innovative design research of multi-degree of freedom rotary 3D printing equipment, determines the printer’s structural parameters based on dimension design, and puts forward the path planning methods for curved layer printing. This paper verifies the correctness of type synthesis and dimension design of the 3D printing equipment through co-simulation and prototype experiments. Meanwhile, preliminary experimental research results show the feasibility of applying 3D printing equipment to curved layer printing from a qualitative point of view. Results of this study provide new ideas for innovative design methods of printing equipment, planning strategies for curved layer printing and related experimental research.
2022, 11(6):23-35.
DOI: 10.12146/j.issn.2095-3135.20220510001
Abstract:
The legged lander is the key equipment of deep space soft landing detection whose current version does not have the mobility capability making its one launching mission’s patrol range limited. In this work, a legged mobile lander is designed and studied. The complete kinematic model is established for a single leg of the legged mobile lander firstly. Then, the working mode of the legged mobile lander is introduced. To make the lander adapt to the complex terrain on the surface of planets, both periodic and free gait planning methods are proposed. The other problems like stability criteria, terrain evaluation as foothold, and foot trajectory planning are also investigated with consideration of the characteristics of the legged mobile lander. Finally, numerical simulation experiments demonstrate the feasibility and stability of the proposed motion planning method.
The legged lander is the key equipment of deep space soft landing detection whose current version does not have the mobility capability making its one launching mission’s patrol range limited. In this work, a legged mobile lander is designed and studied. The complete kinematic model is established for a single leg of the legged mobile lander firstly. Then, the working mode of the legged mobile lander is introduced. To make the lander adapt to the complex terrain on the surface of planets, both periodic and free gait planning methods are proposed. The other problems like stability criteria, terrain evaluation as foothold, and foot trajectory planning are also investigated with consideration of the characteristics of the legged mobile lander. Finally, numerical simulation experiments demonstrate the feasibility and stability of the proposed motion planning method.
2022, 11(6):36-47.
DOI: 10.12146/j.issn.2095-3135.20211229002
Abstract:
Collaborative robots or Co-robots are widely used in automation industries and material handling. Co-robots are designed to work with human workers side by side. However, safety is a challenging major concern. Rigidity is required to carry a payload and achieve accuracy in motion, while flexibility is often required for safe human interaction. Robots with control over their stiffness could combine some of the advantages seen in compliant robots with the performance of traditional rigid robots. This paper introduces the related research on variable stiffness robots and several variable stiffness solutions based on mechanical structures. These methods are classified based on the working principles and compared quantitatively based on the criteria such as stiffness range, stiffness ratio, and response time. Pros and cons are also described for each method. Researchers in design innovation and simulation laboratory also present several example applications of these variable stiffness mechanisms to collaborative robotic arms and grippers.
Collaborative robots or Co-robots are widely used in automation industries and material handling. Co-robots are designed to work with human workers side by side. However, safety is a challenging major concern. Rigidity is required to carry a payload and achieve accuracy in motion, while flexibility is often required for safe human interaction. Robots with control over their stiffness could combine some of the advantages seen in compliant robots with the performance of traditional rigid robots. This paper introduces the related research on variable stiffness robots and several variable stiffness solutions based on mechanical structures. These methods are classified based on the working principles and compared quantitatively based on the criteria such as stiffness range, stiffness ratio, and response time. Pros and cons are also described for each method. Researchers in design innovation and simulation laboratory also present several example applications of these variable stiffness mechanisms to collaborative robotic arms and grippers.
