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One of the first steps in designing a flexible assembly system is the selection of an appropriate manipulator. There are a number of different manipulator configurations which can be chosen depending on a variety of factors such as the assembly workspace layout, product size, weight, and component insertion direction.A number of methodologies have been written to help the selection of a manipulator for process cells. However, little work exists to aid the machine designer in the selection of an appropriate manipulator for flexible assembly. This paper examines the factors which affect this process.

This paper aims to develop an easily reconfigurable assembly cell.

Some functions are implemented to resolve problems associated with physical reconfiguration of an agent‐based robotic assembly cell, such as position calibration and workspace allocation.

The implemented prototype assembly cell is composed of industrial manipulators and a belt conveyor. Installation of a new manipulator and assembly execution are successfully demonstrated on the prototype cell.

In the developed assembly system, installation and removal of assembly devices are easily performed so that it can adapt to changes in the manufacturing environment quickly.

The developed system does not use specially designed hardware. Easy reconfiguration is enabled using conventional devices such as manipulators and belt conveyors.

This paper describes many sensors which are applicable to the requirements of the computer controlled assembly and manufacturing process. Various new types of sensors are presented including a multi‐degree of freedom force sensor using interchangeable modules, a pneumatic retractable whisker, an ultrasonic probe and various tactile and optical image sensors.

Existing models of product assembly scheme design often ignore the constraint relations among design thinking. In order to grasp the functions of each part and the constraint relations among them in product assembly system macroscopically, further design and variation of product assembly system should be made according to design thinking. This paper seeks to address these issues.

Through analyzing the similarity between biological organization system and product system and taking biology knowledge for reference, product assembly system was expressed as product function gene, product constraint gene, product function protein, product constraint protein and product cell and so on in this paper. The product gene model composed of product function gene groups and constraint genes was established and a modeling method based on it was proposed.

The author applied this method to model the 5‐DOF manipulator of complex diamond manufacturing special equipment with good results which proved the effectiveness of this modeling method.

By identifying constraint relations and design thinking in the gene model, the system makes the modification process which is conducted by the designers automatically identified and varied to achieve computer‐aided design and assembly.

The force sensing is used in robotic assembly tasks. The sensors developed are much advanced and costly. The force transducers are generally configured and deployed at the wrist of the robotic arm. The purpose of this paper is to describe the concept of an elastic transducer to make available cost-effective force sensor with simple construction and analysis.

The analytical formulation is developed herewith for one-, two- and three-axis elastic cantilever configuration. The force to be measured can be calculated analytically using derived strain expressions. The strains are estimated using proposed formulation, further crosschecked through FEA approach. The analytical method for strain estimation using moment equations is presented along with validation using finite element method (FEM) tool (ANSYS 15.0) with the case study.

The derivation of expressions for force components from strains is developed. The resulting formulation found to confirm the estimated strains from analytical methods closely to the FEM results. Theoretically, it is possible to find contact forces and angle of force on stationary force platform. It is found that the magnitude of estimated contact forces is within 1 per cent deviations.

The mathematical modeling and FEA simulation of the three-axis force sensor under elastic (no deformation) conditions.

These sensors are ranging from simple crossbar structure to Stewart platform type. The subsequent development in this field pertains to performance enhancement such as accuracy and cross-sensitivity. The basic structure of the sensor has not changed drastically. The major problem, as discussed by many authors, is a complex interdependence of six components and intricate geometrical structure. Derivation of expressions for force components from strains is a breakthrough contribution by the authors. The analytical treatment for finding the strains is aimed in this paper.

The purpose of this paper is to present a dual manipulator system for aloft hot-line assembly tasks of connection fittings in 110-kv intelligent substation, which is significant to the research on hot-line working robots.

This paper addresses the challenges of the task and presents a dual manipulator system which can overcome these challenges to realize the robotic assembly of connection fittings in narrow space without impacting the safe distance of both phase to phase and phase to ground. Two manipulators share a same global reference coordinate. The mission of Manipulator 1 is to position the fixed part of connection fittings and screw the bolts on it. Visual computing provides the approximately position for the end-effector of Manipulator 2, after which The Manipulator 2 carries the removable part of connection fittings to this position. Then, the assembly task could be completed with the posture of the Manipulator 2 adjusted following the guidance by force-position control.

The dual manipulator system can position the target under different illumination conditions and complete fast assembly of connect fittings in 110-kV substation. No strong arc discharge or surface erosion phenomenon has been observed.

This dual manipulator system will be particularly useful for the hot-line assembly of connection fittings in 110-kv intelligent substation, as well as some assembly tasks where uncertain target position and complex contact surface such as cylindrical hole is involved.

This study presents a dual manipulator system used by a field robot working in 110-kv intelligent substation. The system is able to achieve the connection fittings assembly task under energized simulation experimental system. Unlike other peg-in-hole assembly strategy, it does not require high stability of manipulator or plane contact surface around the hole.

The purpose of this paper is to provide a safe control strategy for aloft hot-line assembly of connection fittings in 110kV intelligent substations, which is significant to research on hot-line working robots.

This paper addresses challenges of the task and establish the contact models of connection fittings. By using this control strategy, neither high precision vision positioning nor preset global reference coordinate system is required. Visual computing only needs to provide an approximately position for the manipulator end-effector, after which the connection fittings assembly task could be completed with the posture of the manipulator adjusted following the guidance by force-position control. The authors also analyze the influence of the intervention of manipulators on the very non-uniform electric field during the operation.

This strategy will be particularly useful for the hot-line assembly of connection fittings in 110kV intelligent substations as well as some assembly tasks where uncertain target position and complex contact surface such as cylindrical hole is involved.

This assembly strategy is tested in energized simulated experimental system. The experiment results show that the robot can replace the manual operation to complete the assembly task safely and efficiently.

This assembly strategy is able to achieve the assembly task of connection fittings. Unlike other peg-in-hole assembly strategy, it does not require high stability of manipulator or plane contact surface around the hole.

The development of a generic flexible assembly system involves the design, selection and integration of a number of different mechanical systems in order to develop an assembly system, which is capable of assembling a wide variety of products having an unknown specification. A specific system configuration being dependent on a variety of factors such as, product size, weight, component insertion direction, and manipulator geometry. This paper examines each of the factors that should be considered when designing a generic flexible assembly system and presents a novel generic flexible assembly system design.

Compared with the robotic manipulation in structured environment, high performance assembly of complex parts in extreme special environment is facing great challenges because of the uncertainty in the environment, and the decline of the control accuracy of the robot and the sensor accuracy. The assembly and construction of the space station is a typical case. An important step in the construction of the space station is the module positioning and docking with the auxiliary of the space manipulator. The operation of the manipulator is faced with many problems, such as low sensing information accuracy, large end position deviation and the requirement of weak impact in the docking process. The purpose of this paper is to design a docking method at the strategy level to effectively solve the problems that may be faced in the docking process.

Inspired by the research of robotic high-precision compliant assembly, this paper introduces the concept of Attractive Region in Environment (ARIE) into the space manipulator–assisted module docking. The contact configuration space of the docking mechanism and the existence of ARIE are systematically analyzed. The docking strategy based on ARIE framework is proposed, in which the impedance control is used to ensure the weak impact during the docking process.

For the androgynous peripheral spacecraft docking mechanism, a large range of attractive region exists in the high-dimensional contact configuration space. The docking strategy based on ARIE framework can be designed according to the geometric characteristics of the constraint region and the structural characteristics of the docking mechanism. The virtual models and the simulation environment are established, and the effectiveness of the proposed method is preliminarily verified.

Based on the research results of robotic precision compliant manipulation, in this paper, the theory of ARIE is first systematically applied to the analysis of spacecraft docking problem and the design of docking scheme. The effectiveness of the proposed docking method is preliminarily verified for the requirements of large position tolerance and weak impact. The research results will provide theoretical support and technical reference for the assembly and construction of space station and other space manipulator operations.

The purpose of this paper is to introduce a novel device to handle a robot manipulator which can grip large‐size panels. This concept arises from questioning why the glazing task is always performed manually and it is assumed that if the panel is handled by worker's bare hands, the material is lifted by a robot system and can be assembled to a frame easily and intuitively.

This study proposes the intuitive manipulator device (IMD) which can be attached on the panel directly and connected to it with the coordinate of robot end‐effector based on a virtual coordinate of IMD. The virtual coordinate is defined by the detection of the location of the IMD from the robot end‐effector using IR sensor scanning and origin point estimation method. In this study, the robot manipulator system is operated by a combination of the commands of two IMDs to perform the panel assembly test and its aspect of input commands is compared with the previous force‐control based human‐robot cooperative systems.

The proposed system shows the better performance while reducing the frequent force reflection of robot system against an environment and simplifies the instant input source for robot control system. Those are caused by the intuitiveness of visual servoing performed by operators and the minimization of a force control strategy by utilizing the operator's own sensitivity. The proposed system shows the possibility of efficiency improvement and simple mechatronic system to realize the automation of panel assembly task.

The proposed device alternates the expensive 6‐axis F/T sensor system to handle the robot manipulator by using the two 3‐axis load cell and those force/torque combinations. Also, the developed device is portable and can attach on the material anywhere. That is why this system could cover various sizes of materials. This system minimizes the computational load to control the robot system and improves the efficiency of an assembly task based on the human‐robot cooperation strategy.