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This paper aims to use the redundancy of a 7-DOF (degree of freedom) serial manipulator to solve motion planning problems along a given 6D Cartesian tool path, in the presence of geometric constraints, namely, obstacles and joint limits.

This paper describes an explicit expression of the task submanifolds for a 7-DOF redundant robot, and the submanifolds can be parameterized by two parameters with this explicit expression. Therefore, the global search method can find the feasible path on this parameterized graph.

The proposed planning algorithm is resolution complete and resolution optimal for 7-DOF manipulators, and the planned path can satisfy task constraint as well as avoiding singularity and collision. The experiments on Motoman SDA robot are reported to show the effectiveness.

This algorithm is still time-consuming, and it can be improved by applying parallel collision detection method or lazy collision detection, adopting new constraints and implementing more effective graph search algorithms.

Compared with other task constrained planning methods, the proposed algorithm archives better performance. This method finds the explicit expression of the two-dimensional task sub-manifolds, so it’s resolution complete and resolution optimal.

Robotic systems for laparoscopic minimally invasive surgery (MIS) always end up with highly sophisticated mechanisms and control schemes – making it a long and hard development process with a steep price. This paper aims to propose and realize a new, efficient and convenient strategy for building effective control systems for surgical and even other complex robotic systems.

A novel method that takes advantage of the modularization concept by integrating two middleware technologies (robot operating system and robotic technology middleware) into a common architecture based on the strengths of both was designed and developed.

Tests of the developed control system showed very low time-delay between the master and slave sides; good movement representation on the slave manipulator; and high positional and operational accuracy. Moreover, the new development strategy trial came with much higher efficiency and lower costs.

This method results in a modularized and distributed control system that is amenable to collaboratively develop; convenient to modify and update; componentized and easy to extend; mutually independent among subsystems; and practicable to be running and communicating across multiple operating systems. However, experiments show that surgical training and updates of the robotic system are still required to achieve better proficiency for completing complex minimally invasive surgical operations with the proposed and developed system.

This research proposed and developed a novel modularization design method and a novel architecture for building a distributed teleoperation control system for laparoscopic MIS.

This paper aims to propose a new solution for real-time 3D perception with monocular camera. Most of the industrial robots’ solutions use active sensors to acquire 3D structure information, which limit their applications to indoor scenarios. By only using monocular camera, some state of art method provides up-to-scale 3D structure information, but scale information of corresponding objects is uncertain.

First, high-accuracy and scale-informed camera pose and sparse 3D map are provided by leveraging ORB-SLAM and marker. Second, for each frame captured by a camera, a specially designed depth estimation pipeline is used to compute corresponding 3D structure called depth map in real-time. Finally, depth map is integrated into volumetric scene model. A feedback module has been designed for users to visualize intermediate scene surface in real-time.

The system provides more robust tracking performance and compelling results. The implementation runs near 25 Hz on mainstream laptop based on parallel computation technique.

A new solution for 3D perception is using monocular camera by leveraging ORB-SLAM systems. Results in our system are visually comparable to active sensor systems such as elastic fusion in small scenes. The system is also both efficient and easy to implement, and algorithms and specific configurations involved are introduced in detail.

Two and one half‐dimensional (2.5D) grid maps are useful for navigation in outdoor environment or on non‐flat surface. However, little attention has been given to how to find an optimal path in a 2.5D grid map. The purpose of this paper is to develop a path‐planning method in a 2.5D grid map, which aims to provide an efficient solution to robot path planning no matter whether the robot is equipped with the prior knowledge of the environment.

A 2.5D grid representation is proposed to model non‐flat surface for mobile robots. According to the graph extracted from the 2.5D grid map, an improved searching approach derived from A* algorithm is presented for the shortest path planning. With reasonable assumption, the approach is improved for the path planning in unknown environment.

It is confirmed by experiments that the proposed planning approach provide a solution to the problem of optimal path planning in 2.5 grid maps. Furthermore, the experiment results demonstrate that our 2.5D D* method leads to more efficient dynamic path planning for navigation in unknown environment.

This paper proposes a path‐planning approach in a 2.5D grid map which is used to represent a non‐flat surface. The approach is capable of efficient navigation no matter whether the global environmental information is available at the beginning of exploration.

The purpose of this paper is to present a distributed multiple mobile robot system that provides a collaborative control and simulation environment.

A CORBA‐based cooperative system is designed to implement a robotic layered cooperative mechanism. The mechanism has three layers: mission, transport and execution. In order to realize a flexible and effective communication in the cooperative mechanism, an extended robot event service (federated event service) is proposed to improve the cooperative system's real time performance.

Experimentation has proved the validity and effectiveness of the system. The federated event service's latency is approximately 9 percent less than the standard event service latency when the CPU is determined.

The robotic modularized system includes the map‐building, path‐planning, robot task‐planning, simulation and actual robot control function modules, and uses CORBA to integrate the whole system. It is easy to implement a layered cooperative mechanism for multiple mobile robots. Given the problem on multiple robots cooperation latency, a useful extended robot event service is proposed.

The paper focuses on the distributed functional modular architecture, and the multiple robots cooperative layered mechanism. In the mechanism, an extended robot event service (federated event service) is proposed to reduce the cooperative system's real time latency. The conducted experiment validates the proposed system with a good performance for multiple mobile robots' cooperation.

Path planning approaches based on conventional occupancy grid maps are problematic in off‐road environment because impossible areas include not only obstacles but also landscapes like ramps and pits. The purpose of this paper is to develop a path planning method in a hybrid grid map, which aims to provide a better solution for outdoor navigation.

A hybrid vision system which consists of one stereo vision and one omnidirectional vision is adopted to provide environmental information for 2.5D grid and 2D grid mapping, respectively. An improved planning method originated from conventional D*‐based search algorithm is proposed for more efficient navigation in such hybrid grid maps.

It is confirmed by simulations and experiments that the path planning in the hybrid grid map is more efficient than that in conventional grid maps. Furthermore, it helps to guarantee a safe exploration for field and planetary robots.

This paper proposes a path planning approach in a hybrid grid map representing unstructured environment. The map consists of two different grid representations with diverse resolutions and structures, named 2.5D and 2D grids. The navigation process is expected to become efficient by reducing the replanning times and track length.

To develop an image processing approach for jigsaw puzzle assembly.

First, pixels are extracted from the jigsaw puzzle blocks to calculate their rotation angles and centre coordinates. Second, a template matching method is employed to recognise each block and its orientation.

A robot‐based jigsaw puzzle system is established; and an effective image processing approach for assembly is developed.

Automatic assembly lines that assemble parts with the same shape, but random position and angle, can employ the jigsaw puzzle assembly method.

An effective image processing method for jigsaw puzzle assembly is presented in this paper. The validity of the method is proved by analysis and experiment.

In this paper, an optical inspection method of the ball grid array package(BGA) is proposed using a binocular machine vision system.

The height of each solder ball is calculated based on spatial geometrical size and location obtained from the two CCD cameras capturing range images of a LED illuminated BGA chip at certain orientation.

The structure of this system is simple and the accuracy is 0.02 mm, The experimental results have proved the validity of this system for BGA failure detection.

The developed machine vision system can provide some of the critical factors for BGA quality evaluation, such as the height of solder ball, diameter, pitch and coplanarity.

Compared with other systems, the structure of this system is simple and accurate, which meets the demand of off‐line and on‐line inspection. The limitation of this system is that the margin of field of view (FOV) is fuzzy. Further study could be focused on this problem.

This paper sets out to propose a wafer prealigner based on multi‐sensor integration and an effective prealignment method implemented on it.

The wafer and notch eccentricities, on which wafer prealignment is based, are calculated with the peripheral data of the wafer detected by a laser displacement sensor and a transmission laser sensor by means of barycenter acquiring algorithm in a one‐particle system.

The center and notch prealignment precisions of the system are, respectively, ±1.5 μm and ±30 μrad. Experimentation has proved the validity and effectiveness of the system.

The wafer prealigner is a subsystem of the lithography in the semiconductor industry. The prealignment algorithm can be implemented in any object with random figures.

The periphery of the wafer is detected by a high‐precision laser displacement sensor and a low‐cost transmission laser sensor instead of a CCD linear sensor used by traditional wafer prealigners, which saves the space occupation of the structure and enhances the systematic prealignment precision. Using barycenter acquiring algorithm in a one‐particle system to calculate the wafer and notch eccentricities is effective and valid.

The purpose of this paper is to propose a suitable motion control method for omni‐directional mobile robots (OMRs) based on anisotropy.

A dynamic modeling method for OMRs based on the theory of vehicle dynamics is proposed. By analyzing the driving torque acting on each axis while the robot moves in different directions, the dynamic anisotropy of OMRs is analyzed. The characteristics of dynamic anisotropies and kinematic anisotropies are introduced into the fuzzy sliding mode control (FSMC) system to coordinate the driving torque as a factor of influence.

A combination of the anisotropy and FSMC method produces coordinated motion for the multi‐axis system of OMRs, especially in the initial process of motion. The proposed control system is insensitive to parametric vibrations and external disturbances, and the chattering is apparently decreased. Simulations and experiments have proven that an effective motion tracking can be achieved by using the proposed motion control method.

In order to obtain a clearer analysis of the anisotropy influence during the acceleration process, only the case of translation motion is discussed here. Future work could be done on cases where there are both translation and rotation motions.

The proposed motion control method is applied successfully to achieve effective motion control for OMRs, which is suitable for any kind of OMR.

The novel concept of dynamic anisotropy of OMRs is proposed. By introducing the anisotropy as an influential factor into the FSMC system, a new motion control method suitable for OMRs is proposed.