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This paper aims to present an iterative path-following method with joint limits to solve the problem of large computation cost, movement exceeding joint limits and poor path-following accuracy for the path planning of hyper-redundant snake-like manipulator.

When a desired path is given, new configuration of the snake-like manipulator is obtained through a geometrical approach, then the joints are repositioned through iterations until all the rotation angles satisfy the imposed joint limits. Finally, a new arrangement is obtained through the analytic solution of the inverse kinematics of hyper-redundant manipulator. Finally, simulations and experiments are carried out to analyze the performance of the proposed path-following method.

Simulation results show that the average computation time is 0.1 ms per step for a hyper-redundant manipulator with 12 degrees of freedom, and the deviation in tip position can be kept below 0.02 mm. Experiments show that all the rotation angles are within joint limits.

Currently , the manipulator is working in open-loop, the elasticity of the driving cable will cause positioning error. In future, close-loop control based on real-time attitude detection will be used in in combination with the path-following method to achieve high-precision trajectory tracking.

Through a series of iterative processes, the proposed method can make the manipulator approach the desired path as much as possible within the joint constraints with high precision and less computation time.

Two-handed automobile steering at low vehicle speeds may lead to reduced steering ability at large steering wheel angles and shoulder injury at high steering wheel rates (SWRs). As a first step toward solving these problems, this study aims, firstly, to design a surface electromyography (sEMG) controlled steering assistance interface that enables hands-free steering wheel rotation and, secondly, to validate the effect of this rotation on path-following accuracy.

A total of 24 drivers used biceps brachii sEMG signals to control the steering assistance interface at a maximized SWR in three driving simulator scenarios: U-turn, 90º turn and 45º turn. For comparison, the scenarios were repeated with a slower SWR and a game steering wheel in place of the steering assistance interface. The path-following accuracy of the steering assistance interface would be validated if it was at least comparable to that of the game steering wheel.

Overall, the steering assistance interface with a maximized SWR was comparable to a game steering wheel. For the U-turn, 90º turn and 45º turn, the sEMG-based human–machine interface (HMI) had median lateral errors of 0.55, 0.3 and 0.2 m, respectively, whereas the game steering wheel, respectively, had median lateral errors of 0.7, 0.4 and 0.3 m. The higher accuracy of the sEMG-based HMI was statistically significant in the case of the U-turn.

Although production automobiles do not use sEMG-based HMIs, and few studies have proposed sEMG controlled steering, the results of the current study warrant further development of a sEMG-based HMI for an actual automobile.

The purpose of this paper is to present a high accuracy path following method for low-cost fixed-wing UAVs.

The original vector field (VF) algorithm is condensed. A spatial integration mechanism is added to the existing VF and nonlinear guidance law, aiming to decrease steady-state cross-track-error and cope with long-term disturbance.

Numerical simulations show the proposed method could diminish steady-state cross-track-error effectively. Test flights show the proposed method is applicable on low-cost fixed-wing UAVs.

The path following accuracy shown in simulations and test flights indicates the proposed method could be deployed in scenarios including inflight rendezvous, formation, trafficway take-off and landing.

This paper provides an improved high-accuracy path following method for low-cost fixed-wing UAVs.

The purpose of this paper is to present an adaptive controller of nonlinear path following for a fix‐wing micro‐aerial‐vehicle (MAV) in flight. The adaptive controller discussed in this work was able to successfully complete the flight tasks in complicated terrain, with improved trajectory tracking precision and flight quality.

The nonlinear desired trajectory was fitted by the method of fifth‐order B‐splines with a sequence of waypoints which are created and sent by the ground station. According to the relationship between the nonlinear desired trajectory and aircraft's flight path, the authors have built the relevant error equations of position and course under wind disturbances, based on the Serret‐Frenet frame. The Lyapunov function can be constructed in virtue of the error equations and desired course function applying the vector field theory. On the basis of Lyapunov stability arguments, the authors have also constituted the course adaptive control law, which is converged asymptotically and stably.

According to the nonlinear desired trajectory fitted by the proposed adaptive control methods, the authors have carried out the flight tests experiments with various positions, courses and airspeeds of aircraft. The experimental results show a good path following, as well as under wind disturbances.

A new methodology for the nonlinear path following has been proposed, which is also proven to be promising for other special applications such as the path following in straight‐line segment and orbit, etc.

The paper provides a novel realization method for accurate path following for MAVs. This method can also be carried out in many applications by a simple hardware.

The purpose of this paper is to present an efficient method to integrate path generation and following for an unmanned aerial vehicle.

The shortest path is briefly reviewed using a straight line and a circular arc in a horizontal plane. Based on shortest paths, various path generation algorithms using oriented waypoints are described. Path design unit, which is structured concatenations of line segments and circular arcs, is proposed to represent different paths as one structure. Simple path following controller to follow a straight line and a circle was also implemented with linear‐quadratic regulator control laws. Some flight tests were conducted to verify the efficiency of proposed algorithm.

Proposed method represents various paths between given waypoints efficiently by a small number of parameters. It does not need a large amount of memory storage and computation time to run in real time on a low‐cost microprocessor.

This paper provides new structured method to generate different paths efficiently including Dubins' set, which makes path following easy by simple switching logic. It needs small computational time to run in real time. The proposed algorithm in this paper could be used as a basis of other applications such as air traffic control and curved landing approach, which require more accurate path control.

This paper aims to present a unified motion control scheme for quadcopters which not only solves the point stabilization and trajectory tracking problems but also the path following problem.

The control problem is solved based on the kinematic model of the unmanned aerial vehicles (UAV). Next, a dynamic compensation controller is considered through of a quadcopter-inner-loop system to independently track four velocity commands: forward, lateral, up/downward and heading rate. Stability and robustness of the whole control system are proved through the Lyapunov’s method. To evaluate the controller’s performance, a multi-user application which allows bilateral communication between a ground station and the Phantom 3 PRO quadrotor is developed.

The performance of the proposed unified controller is shown through real experiments for the different motion control objectives: point stabilization, trajectory tracking and path following. The experiments confirm the capability of the unified controller to solve different motion problems by an adequate selection of the control references.

This work proposes the design of three types of motion controllers, which can be switched to comply a task in outdoor. Based on the software development kit provided by the company DJI, an application to get and send data to the UAV is developed. By means of this application, the three tasks are tested and the robustness of the controllers is proved.

To answer the questions: what roles windows of opportunity act in the catchup process of latecomers, what strategies latecomer enterprises should adopt to size windows of opportunity to catch-up with incumbents even going beyond?

This paper studies the catch-up history of the Chinese mobile phone industry and proposes a sectoral innovation system under scenario of technology paradigm shifts. Then a history-friendly simulation model and counterfactual analysis are conducted to learn how different windows of opportunity and catch-up strategies influence the catch-up performance of latecomers.

Results show latecomers can catch up with technology ability by utilizing technology window and path-creating strategy. However, catching up with the market is not guaranteed. Demand window can help latecomers to catch up with market as it increases their survival rates, different sized windows benefit different strategies. However, it also enlarges incumbents' scale effect. Without technology window technology catch up is not guaranteed. Two windows have combination effects. Demand window affects the “degree” of change in survival rates, while the technology window affects the “speed” of change. Demand window provides security; technology window provides the possibility of a breakthrough for technology ability.

The findings of this paper provide theoretical guidance for latecomer enterprises to choose appropriate catch-up strategies to seize different opportunity windows.

This paper emphasizes the abrupt change of industrial innovation system caused by technology paradigm shifts, which makes up for the shortcomings of previous researches on industrial innovation system which either studied the influence of static factors or based on the influence of continuous changes.

The purpose of this paper is to present a path planning algorithm for a non‐circular shaped mobile robot to autonomously navigate in an unknown area for humanitarian demining. For that purpose the path planning problem comes down to planning a path from some starting location to a final location in an area so that the robot covers all the reachable positions in the area while following the planned path.

The proposed algorithm uses occupancy grid map representation of the area. Every free cell in the grid map represents a node in the graph being searched to find the complete coverage path. The complete coverage path is followed by the dynamic window algorithm, which includes robot's kinematic and dynamic constraints.

The proposed algorithm finds the complete coverage path in the graph accounting for the dimensions of the mobile robot, where non‐circular shaped robots can be easily included. The algorithms are implemented under the ROS (robot operating system) and tested in the stage 3D simulator for mobile robots with a randomly generated simulation map of an unknown area.

Some parts of the area close to obstacles are hard to cover due to complex non‐circular shaped robot and non‐perfect path following. The future work should include better path following algorithm.

The proposed algorithm has shown itself as effective and could meet the working demands of humanitarian demining.

The algorithm proposed in the paper enables complete coverage path planning of non‐circular shaped robots in unknown areas.

The purpose of this paper is to discuss the development of high‐tech industry and the dynamics of technological learning, innovation, entrepreneurship in China through the telecom‐equipment industry.

The paper derives a number of research propositions from the literature and then uses four case studies to show how domestic firms narrow their technological gap in different stages of catch‐up and how these firms have been influenced by their innovation capabilities to catch up to the multinationals.

The major findings of the paper may be summarized as follows. First, the innovation capability and self‐developed technologies have been the key to leading domestic firms in catching‐up with the MNCs. Second, leading domestic firms mainly depend on in‐house R&D development, supplemented with external alliance to build their innovation capability. Third, there are two different catching‐up patterns in China's telecom‐equipment industry. One is “path‐following” catching‐up in global system for mobile communication driven by using new technology in low‐end market. The other is “leapfrogging” catching‐up in the development of phone digital switches and China's own 3G standard (time division – synchronous code division multiple access). However, it seems that the leapfrogging strategy will meet more challenges and problems than the path‐following strategy.

Based on the previous researches about technological learning, innovation and catch‐up in the newly industrializing economies, the paper provides a comprehensive elaboration in Chinese telecommunication industry by using case study approach in an original way.