Papers by Author: Lu Min Chen

Abstract: Drum granulators are widely used in powder granulation industry, and particles’ sphericity is one of the important indexes of drum granulation quality. To improve the particle sphericity, it is necessary to study the influence of particle size and shape on particles’ motion of both attitude and trajectory in the drum. This paper presents a mixed method of the discrete element simulation, orthogonal design experiment and mathematical statistics to investigate the influencing factors of particle orientation. The study found that there is a certain effect of particle shape, size and the speed of the drum on the particle orientation. According to the range analysis, it can be concluded that the effect of the three factors on the particle orientation is in the order of particle shape > particle size > the speed of the drum. Optimum combination was observed to be particle shape, size, and the speed of the drum are homogeneous ellipsoidal particles, 3 mm and 40 rpm, respectively. The study will facilitate to optimize the granulation process parameters.

Abstract: A 2DOF ankle joint mechanism with cross rotation axis was designed to imitate the human ankle joint structure. The kinematic model of the ankle joint mechanism was established by D-H method. The synergistic influences of the angle of ankle joint and subtalar joint on the foot motion of inversion/eversion, adduction/abduction, dorsiflexion/plantar flexion were analyzed by kinematics simulation. The simulation results show that the designed ankle joint has similar motion range and function to that of human ankle. This study provides a theoretical basis for the development of high performance ankle joint for humanoid robots.

Abstract: The process of drum granulation is forming agglomerate by infiltrating liquid or binder into solid fine powder to produce bond force. Seed particles present different shapes features in granulation process. Different shapes of particles will have different movement trajectory and attitude under the condition of different location or rotational speed in the cylinder. The motion pose of different shape particles are analyzed by the simulation method using discrete element method, this way is better for us to control the time of powder in different drum position and frequency of adding powders per time. Research provides the theoretical basis on regulatory means and control parameters for adding powders and guarantee the production efficiency.

Abstract: This paper proposes a novel architecture for a biped robot with six DOFs per leg and an active toe DOF (Degrees of Freedom). The arrangement of three successive DOFs paralleled to each other makes its inverse kinematics simple and decoupled by omitting one DOF which is unnecessary when walking. And this work presents close equations for the forward and inverse kinematics. The results can be used in the kinematic control study of the robot.

Abstract: The working space of manipulator is an important dynamic index. Based on Monte-Carlo method, working space of the 6-DOF (degrees of freedom) underwater manipulator is analyzed in this paper. The virtual prototype of the manipulator is established. Simulation graph is obtained with the aid of arithmetic procedure and computer graphical. Simulation result shows that the manipulator’s working space is bigger and has obtained better effect, which can meet the 6-DOF underwater manipulator operational requirements. The results provide an important reference for the 6-DOF underwater manipulator body design and trajectory planning.