Zijie Niu, Aiwen Zhan and Yongjie Cui
The purpose of this study is to test a chassis robot on rugged road cargo handling.
Abstract
Purpose
The purpose of this study is to test a chassis robot on rugged road cargo handling.
Design/methodology/approach
Attitude solution of D-H series robot gyroscope speed and acceleration sensor.
Findings
In identical experimental environments, hexapodal robots experience smaller deviations when using a four-footed propulsive gait from a typical three-footed gait for forward motion; for the same distance but at different speeds, the deviation basically keeps itself within the same range when the robot advances forward with four-foot propulsive gait; because the foot slide in the three-footed gait sometimes experiences frictions, the robot exhibits a large gap in directional deviations in different courses during motion; for motion using a four-footed propulsive gait, there are minor directional deviations of hexapodal robots resulting from experimental errors, which can be reduced through optimizing mechanical structures.
Originality/value
Planning different gaits can solve problems existing in some typical gaits. This article has put forward a gait planning method for hexapodal robots moving forward with diverse gaits as a redundant multifreedom structure. Subsequent research can combine a multiparallel-legged structure to analyze kinematics, optimize the robot’s mechanical structure and carry out in-depth research of hexapod robot gaits.
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Keywords
Niu Zijie, Zhang Peng, Yongjie Cui and Zhang Jun
Omnidirectional mobile platforms are still plagued by the problem of heading deviation. In four-Mecanum-wheel systems, this problem arises from the phenomena of dynamic imbalance…
Abstract
Purpose
Omnidirectional mobile platforms are still plagued by the problem of heading deviation. In four-Mecanum-wheel systems, this problem arises from the phenomena of dynamic imbalance and slip of the Mecanum wheels while driving. The purpose of this paper is to analyze the mechanism of omnidirectional motion using Mecanum wheels, with the aim of enhancing the heading precision. A proportional-integral-derivative (PID) setting control algorithm based on a radial basis function (RBF) neural network model is introduced.
Design/methodology/approach
In this study, the mechanism of omnidirectional motion using Mecanum wheels is analyzed, with the aim of enhancing the heading precision. A PID setting control algorithm based on an RBF neural network model is introduced. The algorithm is based on a kinematics model for an omnidirectional mobile platform and corrects the driving heading in real time. In this algorithm, the neural network RBF NN2 is used for identifying the state of the system, calculating the Jacobian information of the system and transmitting information to the neural network RBF NN1.
Findings
The network RBF NN1 calculates the deviations ?Kp, ?Ki and ?Kd to regulate the three coefficients Kp, Ki and Kd of the heading angle PID controller. This corrects the driving heading in real time, resolving the problems of low heading precision and unstable driving. The experimental data indicate that, for a externally imposed deviation in the heading angle of between 34º and ∼38°, the correction time for an omnidirectional mobile platform applying the algorithm during longitudinal driving is reduced by 1.4 s compared with the traditional PID control algorithm, while the overshoot angle is reduced by 7.4°; for lateral driving, the correction time is reduced by 1.4 s and the overshoot angle is reduced by 4.2°.
Originality/value
In this study, the mechanism of omnidirectional motion using Mecanum wheels is analyzed, with the aim of enhancing the heading precision. A PID setting control algorithm based on an RBF neural network model is introduced. The algorithm is based on a kinematics model for an omnidirectional mobile platform and corrects the driving heading in real time. In this algorithm, the neural network RBF NN2 is used for identifying the state of the system, calculating the Jacobian information of the system and transmitting information to the neural network RBF NN1. The method is innovative.
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Naihao Li, Zijie Li, Banruo Zhang and Yan Wang
Information transparency is an important factor in enhancing trust and promoting interfirm cooperation. By combining transaction cost theory and institutional theory, this study…
Abstract
Purpose
Information transparency is an important factor in enhancing trust and promoting interfirm cooperation. By combining transaction cost theory and institutional theory, this study aims to examines whether host-country firms’ information transparency prompt multinational enterprises’ (MNEs) to choose the joint venture entry mode for outward foreign direct investment (OFDI).
Design/methodology/approach
Using Heckman two-stage estimation method, this study examines Chinese listed manufacturing firms for the period 2014–2019.
Findings
The findings indicate that the higher the information transparency of host-country firms, the higher the possibility of MNEs choosing the joint venture entry mode for OFDI. This study further finds that the positive relationship between host country firms’ information transparency and the possibility of choosing the joint venture entry mode is enhanced by institutional distance, but weakened by MNEs’ host-country experience.
Originality/value
How to choose the appropriate entry mode of OFDI in the internationalization strategy is an important issue for MNEs to consider. As the postpandemic world is characterized by increased global risks, decoupling of economies, disruption of global value chains and the retreat of globalization (Contractor and Cantwell, 2022), how to further strengthen cooperation, reduce the cost and risk of MNEs and truly realize common construction and sharing is one of the hot issues in both practice and research.
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Keywords
Long Wang, Fengtao Wang, Linkai Niu, Xin Li, Zihao Wang and Shuping Yan
The purpose of this paper is to combine triboelectric nanogeneration technology with ball bearing structure to achieve energy collection and fault monitoring.
Abstract
Purpose
The purpose of this paper is to combine triboelectric nanogeneration technology with ball bearing structure to achieve energy collection and fault monitoring.
Design/methodology/approach
In this paper, according to the rotation mode of ball bearings, the freestanding mode of triboelectric nanogeneration is selected to design and manufacture a novel triboelectric nanogeneration device Rolling Ball Triboelectric Nanogenerator (RB-TENG) which combines rotary energy collection with ball bearing fault self-sensing.
Findings
The 10,000s continuous operation experiment of the RB-TENG is carried out to verify its robustness. The accurate feedback relationship between the RB-TENG and rotation velocity can be demonstrated by the fitting comparison between the theoretical and experimental electrical signal periods at a certain time. By comparing the output electrical signals of the normal RB-TENG and the rotor spalling RB-TENG and polytetrafluoroethylene (PTFE) balls with different degrees of wear at 500 r/min, it can be concluded that the RB-TENG has an ideal monitoring effect on the radial clearance distance of bearings. The spalling fault test of the RB-TENG stator inner ring and rotor outer ring is carried out.
Originality/value
Through coupling experiments of rotor spalling fault of the RB-TENG and PTFE balls fault with different degrees of wear, it can be seen that when rotor spalling fault occurs, balls wear has a greater impact on the normal operation of the RB-TENG, and it is easier to identify. The fault self-sensing ability of the RB-TENG can be obtained, which is expected to provide an effective scheme for monitoring the radial wear clearance distance of ball bearings.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0295/