Wencheng Tang

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Based on the principle of double-half-revolution mechanism, this paper designed a new-style bionic walking mechanism by using two tandem planetary gear trains, which is composed of one first swiveling arm, one second swiveling arm, two striding rods and mechanism bracket, etc. The first swiveling arm and second swiveling arm are the planet carriers (also as(More)
Vitellogenin (Vg) cDNA from Spodoptera litura Fabricius was cloned and sequenced. The open reading frame (ORF) of Vg cDNA was 5247 nucleotides in length (GenBank Accession no. EU095334), which encoded for a protein of 1748 amino acids. S. litura Vg comprised three conserved regions (Vitellogenin-N domain, DUF1943 and von Willebrand factor type D domain(More)
Deficiency has been found in the current collaborative design systems. It is difficult and inconvenient to co-design on a Web CAD tool. New products to be designed are more and more complicated, and new requirements are advanced that automatic processes need to be used in collaborative design. A new concurrent engineering (CE) model based on automatic(More)
Dynamic simulation of alveolar bone remodeling is important for orthodontic study and clinical operation, but dynamic simulation based on tissue change has never been realized. Based on a remodeling model obtained from data in literature, using a viscoelastic constitutive model of periodontal ligament obtained by experiment data fitting, the alveolar(More)
The paper presents a new hybrid global optimization algorithm based on chaos search and complex method for nonlinear constrained optimization problems. To fit for chaos optimization algorithm, a constrained optimization problem is transformed into an unconstrained problem by penalty function method. The mapping mode of standard complex method is improved to(More)
This paper presents a method to design servo controllers for flexible ball screw drives with time-varying dynamics, which are mainly due to the time-varying table position and the workpiece mass. A gain-scheduled H∞ loop shaping controller is designed to achieve high tracking performance against the dynamic variations. H∞ loop shaping design procedure(More)
This paper presents a method to design servo controller for flexible ball screw drives. The state space model of the flexible ball screw drive with the nonminimum phase zero is considered. An adaptive backstepping sliding mode controller with minimum tracking error prefilter is proposed to actively suppress for the vibrations and achieve high positioning(More)
The re-circulating mechanism of ball screws plays a vital role for its providing the path for steel balls rolling in screw grooves generally in high-speed/high-precision ball screw transmitting systems. However it is very hard to directly measure the ball's motion in the re-circulation for the closed recirculation groove. In order to investigate the(More)