DIRECT DIGITAL DESIGN AND SIMULATION OF MESHING IN WORM-GEAR DRIVE

A direct digital design method （DDDM） of worm-gear drive is proposed. It is directly based on the simulation of manufacturing process and completely different from the conventional modeling method. The loaded tooth contact analysis （LTCA） method is analyzed, in which the advanced surface to surface searching technique is included. The influence of misalignment errors and contact deformations on contact zone and transmission error （TE） is discussed. Combined modification approach on worm tooth surface is presented. By means of DDDM and LTCA, it is very conven- ient to verify the effect of worm-gear drive＇s modification approach. The analysis results show that, the modification in profile direction reduces the sensitivity of worm-gear drive to misalignment errors and the modification in longitudinal direction decreases the TE. Thus the optimization design of worm-gear drive can be achieved prior to the actual manufacturing process.

A Hybrid Si IGBT and SiC MOSFET Module Development

A compact wirebond packaged phase-leg SiC/Si hybrid module was designed,developed,and tested.Details of the layout and gate drive designs are described.The IC chip for gate drive is carefully selected and compared.Dual pulse test confirmed that,the switching loss of hybrid module is close to pure SiC MOSFET module,and it is much less than pure Si IGBT device.The cost of hybrid module is closer to Si IGBT.

The Impulse Excitation Joint Servo Drive Design and Adaptive Backstepping Control of Humanoid Robots

This study aims to explore the humanoid robot joint servo drive integration design and adaptive backstepping control. To make the humanoid robot have explosive power as the human does, simply increasing the power output of the motor of a lightweight design cannot meet the demand of moving heavy objects and so on. Moreover, the backstepping control algorithm is designed to implement the dual-arm cooperative control. The joint servo drive is redesigned in the present study, which can drive the motor at a limitation state when needed output high-voltage pulse can stimulate the motor so that the motor can produce an instantaneous large torque. A miniature design scheme is presented in this study for the servo drive, explaining the design method of each part module. The ex- perimental data illustrate that the servo drive can produce an output torque greater than the rate of the high-voltage pulse that stimulates the motor. Knowledge of the control of humanoid robot moving a heavy object has important practical significance. The present study provides a complete actual problem and exhibits a real practical use case which can be used to speed up the explosive humanoid robot arms.

Establishing distinctive theories and methods of design science rooted in Chinese traditional culture

The human social development saw the formation of five unique civilizations,with the latter forming their own distinctive cultures.China’s traditional culture is its most fundamental ideological weapon for solving problems.The Chinese are good at comprehensive thinking,dialectical thinking,and systematic analysis.These ideological weapons can solve the problems of formal science and technology and create scientific and technological achievements on par with global advanced scale.Ancient China is filled with original scientific and technological achievements,which strongly prove ancient China’s possession of its own science and technology different from that of Western Renaissance.Therefore,a comprehensive understanding of science,technology,experience,and intuition is necessary.The long-held superstition regarding the West,the lack of confidence,self-denial,blind imitation of ideas,and shackles must be thrown away.Only then can we take the road toward an authentic Chinese creative design as we learn from others.

Matching design of hydraulic load simulator with aerocraft actuator

This paper intends to provide theoretical basis for matching design of hydraulic load simulator （HLS） with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of ＂Standard Actuator＂ and ＂Standard HLS＂. Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences.