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This paper presents a new method to automate robot motion planning in automotive manufacturing environments. A general framework is developed for CAD‐guided robot motion planning. The problem is formulated as a constraint‐satisfying problem of tool configurations or, robot hand poses. Two types of robot motion are considered: discrete motion, or point to point motion, and continuous motion. Triangular facets are used to approximate the part surfaces. A pre‐partition process decomposes the complex part surfaces into several simple, easy‐to‐solve patches. For each patch, robot hand poses are determined to satisfy certain task constraints. In this paper, the approach is applied to two applications: vision sensor planning and spray painting gun path planning. It is our belief that more robot planning applications in manufacturing can benefit from this method.

The disinfection robot developed by the authors and team focuses on achieving fast and precise disinfection under a given or specific disinfection zone. This looks to solve problems with traditional robots that pay less attention to the level, efficiency and zones of disinfection. To effectively support and guarantee normal running for the whole system, a digital twin system is applied to the disinfection robot. This study aims to achieve fast, precise and thorough disinfection via the developed mobile robot.

The designed robot is composed primarily of the following three parts: a mobile platform, a six-axis robotic arm and a ultraviolet-C (UVC) LED array. The UVC LED array is installed on the end-effector to achieve large-scale, precise manipulation. The adoption of all types of advanced sensors and the development of an intuitive and user-friendly client interface are helpful in achieving remote control, path planning, data monitoring and custom disinfection functions.

Disinfection of three different locations in the laboratory was performed; the dosage distribution of the surface as radiated by the UVC robot was detected; and feasibility of development was validated.

The developed disinfection robot achieved fast, precise and thorough disinfection for a given or specific disinfection zone.

The purpose of this paper is to develop digital flexible pre-assembly tooling system for fuselage panels.

First, the paper analyzes the technological characteristics of fuselage panels and then determines the pre-assembly object. Second, the pre-assembly positioning method and assembly process are researched. Third, the panel components pre-assembly flexible tooling scheme is constructed. Finally, the pre-assembly flexible tooling system is designed and manufactured.

This study shows the novel solution results in significantly smaller tooling dimensions, while providing greater stability. Digital flexible assembly is an effective way to reduce floor space, reduce delivery and production lead times and improve quality.

The tooling designed in this case is actually used in industrial application. The flexible tooling can realize the pre-assembly for a number of fuselage panels, which is shown as an example in this paper.

The paper suggests the fuselage panel pre-assembly process based on the thought including pre-assembly, the automatic drilling and riveting and jointing, and constructs a flexible tooling system for aircraft fuselage panel component pre-assembly.

The purpose of this paper is to study the influence of large-area texture/slip surface, especially the area and position of large-area texture surface on journal bearing, and improve the tribological performances of journal bearing.

A modified texture/slip numerical boundary condition with double parameters is presented and is applied onto the region where surface textures locate to represent the impact of actual texture/slip surface. A phase change condition is used to analyze cavitation phenomena.

The global/cumulative texture effect can be represented by applying texture/slip condition onto the region where it locates. The area and position of texture/slip surface would significantly affect the cavitation and load-carrying capacity. Texture/slip surface would not affect the pressure and load-carrying capacity when it locates at cavitation zone. The effect of texture/slip surface on load-carrying capacity would be beneficial if it locates at the pressure rise region, but its effect would be adverse if it locates at the pressure drop region. Well-designed texture/slip surface can improve tribological performances.

The developed texture/slip boundary condition can be a suitable and useful tool to analyze the effect of large-area texture/slip surface and especially to optimize the area and position of large-area texture surface. This approach can be complementary to conventional approach which is used to analyze the influence of textures’ real configurations and parameters.

This paper presents our development of a novel Internet‐based E‐manufacturing system to advance applications in micromanipulation and microassembly using an in situ polyvinylidene fluoride (PVDF) piezoelectric sensor. In this system, to allow close monitoring of magnitude and direction of microforces (adhesion, surface tension, friction, and assembly forces) acting on microdevices during assembly, the PVDF polymer films are used to fabricate the highly sensitive 1D and 2D sensors, which can detect the real‐time microforce and force rate information during assembly processes. This technology has been successfully used to perform a tele‐assembly of the surface MEMS structures with force/visual feedback via Internet between USA and Hong Kong. Ultimately, this E‐manufacture system will provide a critical and major step towards the development of automated micromanufacturing processes for batch assembly of microdevices.

Aims to demonstrate how an automated robot program generation method can be developed and implemented.

A visual and force servoing method to automatically generate robot paths and robot programs, based on position, force and vision sensor fusion, was developed.

By using a hybrid control algorithm the robot is controlled to follow the feature on a surface with position and orientation control.

The developed method can be applied to generate tool paths for many manufacturing tasks automatically, which can greatly reduce the robot programming time and decrease the manufacturing cost.

Automatic trajectory generation for spray painting is highly desirable for today’s automotive manufacturing. Generating paint gun trajectories for free‐form surfaces to satisfy paint thickness requirements is still highly challenging due to the complex geometry of free‐form surfaces. In this paper, a CAD‐guided paint gun trajectory generation system for free‐form surfaces has been developed. The system utilizes the CAD information of a free‐form surface to be painted and a paint gun model to generate a paint gun trajectory to satisfy the paint thickness requirements. A paint thickness verification method is also provided to verify the generated trajectories. The simulation results have shown that the trajectory generation system achieves satisfactory performance. This trajectory generation system can also be applied to generate trajectories for many other CAD‐guided robot trajectory planning applications.

Automated chopper gun trajectory planning (CGTP) for spray forming is highly desirable for today's automotive manufacturing. Generating chopper gun trajectories for free‐form surfaces to satisfy material distribution requirements is still highly challenging due to the complexity of the problems. In this paper, a user‐friendly software for automated CGTP has been developed. The CGTP software can take different formats of the CAD models of parts. A chopper gun trajectory is generated based on the CAD model of a part, chopper gun model, and constraints. A part is partitioned into patches to satisfy the given constraints. A trajectory integration algorithm is developed to integrate the trajectories of the patches to form a trajectory for the part. The CGTP software has been tested by Ford Motor Company and achieved satisfactory results.

In this paper, a new cooperation control scheme for multiple robot material handling is presented. First, the event‐based planning and control method is introduced, which lays down the foundation for sensor‐referenced cooperation of multiple robot systems. The key step is the development of event‐based action reference. Based on the real‐time sensory information, the event‐based action reference drives the system to achieve the best possible coordination. The event‐based cooperation control scheme can easily be implemented in a distributed computer system. A real‐time control and computing architecture is proposed to implement this scheme in a parallel computation. The new multiple robot cooperation scheme has been experimentally implemented and tested on two 6‐DOF PUMA 560 robots. The experimental results have demonstrated the advantages of the scheme.

The industrial robot has high repeatability but low accuracy. With the industrial robot being widely used in complicated tasks, e.g. arc welding, offline programming and surgery, accuracy of the robot is more and more important. Robot calibration is an efficient way to improve the accuracy. Previous methods such as using coordinate measurement machines, laser trackers or cameras are limited by the cost, complex operation or the resolution. The purpose of this paper is to propose an approach and calibration equipment to address these issues.

The proposed method relies mainly upon a laser pointer attached on the end‐effector and single position‐sensitive devices (PSD) arbitrarily located on the workcell. The automated calibration procedure (about three minutes) involves aiming the laser lines loaded by the robot towards the center of the PSD surface from various robot positions and orientations. The localization is guaranteed by precise PSD feedback servoing control, which means physically the intersections of each pair of laser lines (virtual lines) are on the same point. Based on the untouched single‐point constraint, the robot joint offset calibration is implemented. Using the authors' proposed approach, a portable, low‐cost, battery‐powered, wireless and automated calibration system was implemented. Error analysis was conducted on the system.

The localization error of the developed calibration system is within 2 μm. The errors in joint space are magnified in PSD plane, and consequently the resolution in the joint space is improved. The standard deviation of the identified parameters was small (10‐2), indicating the stability of the calibration method. Both simulation and experimental results verify the feasibility of the proposed method and demonstrate the developed calibration system can identify joint offset with uncalibrated laser tool parameters.

The paper shows how a portable calibration system for joint offset of industrial robots was developed and how the goal of fast, automated, low‐cost, portable, and high precision calibration methods for joint offset was achieved.