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The purpose of this paper is specifically to provide a more intelligent locomotion planning method for a hexapod robot based on trajectory optimization, which could reduce the complexity of locomotion design, shorten time of design and generate efficient and accurate motion.

The authors generated locomotion for the hexapod robot based on trajectory optimization method and it just need to specify the high-level motion requirements. Here the authors first transcribed the trajectory optimization problem to a nonlinear programming problem, in which the specified motion requirements and the dynamics with complementarity constraints were defined as the constraints, then a nonlinear solver was used to solve. The leg compliance was taken into consideration and the generated motions were deployed on the hexapod robot prototype to prove the utility of the method and, meanwhile, the influence of different environments was considered.

The generated motions were deployed on the hexapod robot and the movements were demonstrated very much in line with the planning. The new planning method does not require lots of parameter-tuning work and therefore significantly reduces the cycle for designing a new locomotion.

A locomotion generation method based on trajectory optimization was constructed for a 12-degree of freedom hexapod robot. The variable stiffness compliance of legs was considered to improve the accuracy of locomotion generation. And also, different from some simulation work before, the authors have designed the locomotion in three cases and constructed field tests to demonstrate its utility.

The purpose of this paper is to describe the design and development of a novel series-parallel robot, which aims to climb on the transmission tower.

This study introduces a hybrid robot, which consists of adsorption and two 3-degree of freedom (DOF) translation parallel legs connected by a body linkage. The DOF of the legs ensures that the robot can move on the climbing plane, also contribute to a compact design of the robot. An electromagnet is used to adsorb onto the transmission tower, simplifying the overall structure. Based on the robot design, this paper further defines its climbing gait and adopt the 6th B-spline curves for climbing trajectory planning under different working environments.

The developed prototype that implements the design of the robot, which was used in simulation and experiments, showing that the robot is capable of climbing in the test environments with the planned climbing gait.

The hybrid robot is able to climb under varying degrees of inclinations and cross the obstacles, and the magnetic attraction can ensure stable climbing.

Overhead high-voltage transmission line (HVTL) inspection robots are used to inspect the transmission lines and/or maintain the infrastructures of a power transmission grid. One of the most serious problems is that the load on the front wheel is much larger than that on the back one when the robot travels along a sloping earth wire. Thus, ongoing operation of the inspection robot mainly depends on the front wheel motor’s ability. This paper aims to extend continuous operation time of the HVTL inspection robots.

By introducing a traction force model, the authors have established a dynamic model of the robot with slip. The total load is evenly distributed to both wheels. According to the traction force model, the desired wheel slip is calculated to achieve the goal of load balance. A wheel slip controller was designed based on second-order sliding-mode control methodology.

This controller accomplishes the control objective, such that the actual wheel slip tracks the desired wheel slip. A simulation and experiment verify the feasibility of the load balance control system. These results indicate that the loads on both wheels are generally equal.

By balancing the loads on both wheels, the inspection robot can travel along the earth wire longer, improving its efficiency.

This paper aims to present a simplified method to predict the pressure of the recess, no matter whether the tilt center coincides with the geometric center of the hydrostatic journal bearings.

To validate the effectiveness of the presented model, computational fluid dynamics (CFD) method and experimental method are performed in this study.

By comparing the CFD results and the experimental results, the pressure of the recess is related to the tilt direction, the tilt center, the width of the land and the circumferential angle of the land.

The mathematic model requires equivalent resistance of land edge – tilt position, tilt direction, tilt angle and the thickness of oil film instead of any digital iteration. Furthermore, a novel experimental apparatus including a circular hydrostatic bearing called ball bearing is designed to study the tilt effect produced by manufacturing error and offset load force on the pressure of the recess.

The purpose of the research is to identify the factors contributing to the formation of high-level strategic thinking ability (STA) of Chinese grassroots cadres.

Through in-depth interviews with 20 Chinese grassroots cadres with high-level STA and grounded theory method, this research explores the contributive factors for the formation of the grassroots cadres' STA from a dynamic and long-term perspective.

The formation of STA is an accumulative process based on the interaction between external factors, including wide space for activities, adequate supporting resources, demonstration of role model, and inflection point and internal drivers, including strong sense of self-actualization, high sense of responsibility, thinking enhancement skills, diverse knowledge and high openness. Moreover, the external factors play a more important role in shaping STA in the early growth stage of the grassroots cadres, while in the late stage the internal factors tend to dominate.

The study advises to offer more professional training on STA and take STA as an important factor for Chinese grassroots cadres to compete in a complex socio-political environment in the long term.

(1) This paper investigates into the STA of Chinese grassroots cadres, which are largely ignored in current literature; (2) different from the extant studies which studies the static influencing factors of STA, such as demographic variables, personal traits and organizational characteristics, this paper focuses on the dynamic and long-term factors during the growth of the cadres.